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11 Electrical and Surface Properties of Metal Oxides By G . R. HEAL Department of Chemistry and Applied Chemistry University of Salford, Salford Lanes. M5 4WT 1 Surface Potential Measurements In recent years the measurement of surface potentials of oxides has been developed particularly by Dereh and co-workers. The quantity actually measured was contact potential difference (CPD) denoted by y where ev = 4 s - 4 x 4s and 4x being the work functions of a standard surface and the sample respec-tively and e being the charge on an electron. The apparatus used was of the vibrating capacitor type. The method was based on the work of Kelvin,' with improvements by Zisman2 and others. In the apparatus described3 an automatic (electronic) compensation of the CPD was used involving an a.c.amplifier and a phase-sensitive rectifier to provide com-pensation voltage. After calibration this apparatus was used to provide rapid measurement of CPD thus allowing the kinetics of change in CPD to bemeasured. An important contribution made was the study of changes in reference-material work function with change in ambient atm~sphere.~ As pointed out by Dere~i,~ little attention had been paid to this effect and some previous workers had ignored it. It was shown in this paper that a platinum reference electrode could be used if the electrode was first standardized by heating it for 20 h at 400°C under 1 mmHg pressure of oxygen. The curve of CPD change against time t, was continuous and followed an equation due entirely to changes on the NiO surface (1) = k t + a A Vmax Avmax - Ar/; In where AV,, is the final change in CPD from vacuum conditions to an infinite time after admission of a fixed pressure of oxygen AV is change in CPD at time t, k is the rate constant for NiO surface charging and a is a constant corresponding to the electric dipole moment of the adsorbed oxygen layer.If the reference G. W. Pratt and H. Kolm Proceedings of the Conference on Semiconductor Surface Physics Philadelphia ed. R. H. Kingston 1957 p. 297. W. A. Zisman Rev. Sci. Instr. 1932 3 367. R. Chrusciel J. Deren and J. Nowotny Exp. Techn. Phys. 1966 14 127. R. Chrusciel J. Deren and J. Nowotny Bull. Acad. polon. Sci. Ser. Sci. chim. 1966, 14 265 222 G. R. Heal platinum electrode was not standardized an extra effect was seen so that AK initially decreased reached a minimum then increased and finally decreased again (Figure 1).This temporary rise in AK was due to an increase of the plati-num work function equal to eAl/dip(Pt) where A&ip(p,) is the change of potential drop at the dipole layer of the adsorbed molecules at the platinum surface. .-.m-. 300 "C -x- 250 "C -v- 200 "C 10 20 30 t/rnin (a) I I I I I I I 60 tlS 40 20 0 ( b) Figure 1 CPD vs. time for the system NiO-Pt non-standardized in the process of oxygen chemisorption (a) t > 1 min (b) t < 1 min (Reproduced by permission from Bull. Acad. polon. Sci. Ser. Sci. chirn. 1966 14 265) The changes at the NiO surface are due to the charging of the surface causing a downward shift in the Fermi surface and an increase of the work function.The process envisaged is a rapid uptake of weakly adsorbed oxygen followed by a slow charging of the NiO surface by the slow establishment of an ionosorptive equilibrium. If dipole potential-drop changes in the adsorbed layer are neglected then A4x = AKe (3) where A4x is the change in work function corresponding to A y . In a later paper,' Deren reported results obtained with pure and doped NiO. He first established that a vacuum of 10-6mmHg was sufficient to clean a J. Deren and J . Nowotny Bull. Acad. polon. Sci. Ser. Sci. chim. 1967 15 115 Electrical and Surface Properties of Metal Oxides 223 surface and a pressure of 1 mmHg of oxygen would produce complete coverage. Observations of kinetics of CPD changes showed that stationary states were reached in shorter times for pure NiO (10min) than for doped NiO (30min), indicating a marked effect produced by additives.The change in CPD upon adsorption of oxygen showed a positive charge on the surface with respect to the bulk of the sample. The changes observed for lithium doping did not entirely agree with changes in thermoelectric power and electrical conductivity. This showed that the effect of additives is different at surfaces in comparison with the bulk since CPD change is a surface-layer effect and the other effects are not. In another paper6 the effect of heating NiO to temperatures between 25 and 400 "C together with cycles of adsorption and desorption of oxygen was used to establish that ionosorption is practically completely reversible above 350 "C but not below that temperature.This showed that a temperature above 350 "C is required in degassing. Investigations of the rate of ionosorption showed an expected rise in rate constant with temperature but a discontinuous jump in value between 250 and 300"C suggesting a change in the mechanism of the process. Further investigations of rate of change of CPD showed that rate is not constant during the initial coverage of the surface but is constant later (after 1 min). Changes in rate constant with respect to doping followed the changes in CPD itself in such a way as to confirm that lowering of surface potential facilitates iono~orption.~ Later work involved oxygen being admitted to NiO at much lower pressures, so that the amount of oxygen adsorbed caused a decrease in the pressure of oxygen.* The first admission of oxygen caused a sharp fall in CPD (rise in work function) but as oxygen pressure fell a peak was reached and then the work function decreased slowly to a constant value (Figure 2).Further admissions of oxygen caused similar effects but at 1 mmHg pressure a constant high value of work function (curve IV) was produced. 0 O,(ads) O,(ads) + 0 Ot-(ads) + 2 0 The most probable form is O-(ads) whereas 02- is regarded as an ion in-corporated into the lattice (@ represents a hole). The results observed were explained by the negative surface charge of ionized oxygen being neutralized by an equal charge of opposite sign in the surface layer of NiO. The electric field then tends to withdraw cations from the bulk to the surface but anions are un-likely to move into the bulk for geometric reasons.Thus new lattice elements, Deren supposed the ionosorption to involve the following equilibria : 20-(ads) + 2 0 2 0 2 - + 4 0 (4) ' J . Deren J. Nowotny and J. Ziolkowski Bull. Acad. polon. Sci. Ser. Sci. chim. 1967, ' J. Deren and J. Nowotny Bull. Acad. polon. Sci. Ser. Sci. chim. 1967 15 121. 15 109. J . Chrusciel J. Deren J. Nowotny and J. Ziblkowski Bull. Acad. polon. Sci. Ser. Sci. chim. 1968 16 215 224 G. R. Heal 4 0.3 -t/ min ( a ) P I I I I I I c 20 40 60 80 100 120 t/min ( b ) Figure 2 (a) Change in work function as a function of time I :$rst cycle I1 second cycle. (b) Changes in work function as a function of time I11 third cycle IV under constant oxygen pressure of 1 mmHg (Reproduced by permission from Bull.Acad. polon. Sci. Ser. Sci. chim. 1968 16 215) which are new adsorption sites appear and cation vacancies form in the surface layers. The potential barrier produced by the initial chemisorption is thus discharged by the reactions : O,(ads) e 2Ni0 + 2Ni, O-(ads) + 0 S 2Ni0 + 2Ni, O;-(ads) + 2 0 * NiO + 2Ni, 02-(ads) + @I 0’- + 2 0 NiO + Ni, NiO + Ni, Ni * Ni,. + 0 Ni,. Ni,, + 0 where Ni represents a nickel vacancy in the lattice and Ni and NiDN vacancies associated with single and double negative charges. The build-up of a defect concentration of Ni in the surface layer leads to a decrease in Fermi le*l position which produces the high value of work function as more and more oxygen is admitted.The electric-field gradient will also decrease and the Ni2 + ions will diffuse more slowly leading to the longer delay Electrical and Surface Properties of Metal Oxides 225 in the peak and equilibrium times in curves I to 111. At high oxygen pressure (curve IV) there is an unlimited amount of oxygen in the gas phase and the potential barrier formed cannot be discharged. Similar experiments' were performed in Li-doped NiO using low oxygen pressures at 400°C (Figure 3). . - ." = 3.3 x ~ - ~ r n m Hg Y x - P ~ = 6 x l O " r n r n Hg . - p ~ = l . O m r n H g ~ - P = 1 0 mrn Hg I I I I I 50 100 150 200 -t/ rnin (b) Figure 3 Changes of the workfunction ofNi0 + 0.24 atom % Li at 400 "C as a function of time.(a) Po' Po1' and PA'' denote oxygen pressure at the beginning of the experimental cycles I 11 and I11 respectively; D evacuation to 5 x mmHg. (b) Polv Pov, Pov1 PoV1' POv1I1 Po1* and Pox denote oxygen pressure at the beginning of the experi-mental cycles IV V VI VII VIII IX and X respectively (Reproduced by permission from Bull. Acad. polon. Sci. Ser. Sci. chim. 1969 17 167) J. Deren and J. Nowotny Bull. Acad. polon. Sci. Ser. Sci. chim. 1969 17 167 226 G. R. Heal At the lower oxygen pressures after the initial peak in work function the equi-librium value was below the original. This was suggested to be due to a change in concentration of Li+ in the surface layer or a transfer of Li+ from lattice sites to interstitial sites with a change in its donor-acceptor- properties.Increase in oxygen pressure shifts equation (4) to the right and also equations (5)-(9). At the temperatures used (below 450°C) the diffusion of Ni2+ from the bulk will be slow so only the surface layer is depleted. In cycle V the potential barrier is not discharged by the Ni2 + ions. When these experiments were repeated at 300 "C the tailing portion was much longer than at 400 "C reflecting the slower diffusion of Ni2+. At 200°C no decrease in work function was observed (as in the case of high oxygen pressure Figure 2 curve IV) thus no discharge by Ni2+ is taking place. A kinetic expression to fit these curves was worked out." This was fitted to the data with an analog computer and it gave rate constants for the chemi-sorption of oxygen and the diffusion of Ni2+ in the surface layer.Another use of the vibrating capacitor technique has been made by Morrison.",'2 He placed a platinum wire near an oxide surface in oxygen and, using a corona discharge of 6OOO V produced a surface electrostatically charged with negative ions. Electrons were then injected from the filled surface states into the conduction band. The energy barrier for the process is the energy difference between the conduction band and the surface-state energy level and may be determined by temperature dependence. The vibrating capacitor was used to monitor decay in surface potential. For the (0007) plane of ZnO there were marked differences for undoped and indium-containing samples. It was expected that the square root of the surface potential would vary linearly with time (electronic effect) and this was indeed so, and for indium-doped samples the activation energy was 0.8eV.He also ex-plained decay for doped samples as possibly due to the reaction (12) in reverse, where Zni represents donors associated with excess Zn. The undoped sample of ZnO did not obey the square root kinetics had faster decay and higher surface potentials and a residual value of surface potential after the decay. The level of residual potential was also higher for higher pre-treatment temperature with oxygen in the corona. These results were taken to be consistent with diffusion of bulk donor to the surface to react as Zni + +02 ZnO (12) The concentration of interstitial Zn near the surface being controlled by this equilibrium Zni is generated under vacuum but depleted in oxygen especially under severe corona treatment.Under these latter conditions more Zn must diffuse long distances to discharge the surface and allow a high remnant potential to persist. On the (OOO1) face even with pre-treatment the decay went to com-l o J. Nowotny Bull. Acad. polon. Sci. Ser. Sci. chim. 1969 17 173. l 2 S. R. Morrison Surface Sci. 1971 27 586. S. R. Morrison Surface Sci. 1969 13 8 5 Electrical and Surface Properties of Metal Oxides 227 pletion at 100°C suggesting that equation (12) proceeds in reverse as well as the donor diffusion reaction. The mechanisms of positive-hole capture and ion motion over the surface are not considered to be feasible. Other reduced form additives were put on the surface after oxygen treatment (adsorbate not ionized).On the (Wf) face the gases H2 and CO had no effect on surface potential but methanol and ethanol injected electrons into the con-duction band as did oxygen with activation energies of 1.3 and 0.5 eV respectively. Possible reasons for this effect were suggested. On the (0001) face both H and H 2 0 produced a temporary increase in rate of decay of potential the rate then returning to normal. Thus only a part of the charge was removed by these gases. Further if alternate treatments of H and H 2 0 were used the second gas gave no increase in decay rate. It was suggested that the corona-treated surface was covered with various ionic species and that both H and H,O reacted with one or more of these species but not the rest.The technique it was suggested is important in catalysis to determine if in-jection occurs and whether reactant products or intermediates are oxidized by injection. In a later paper12 Morrison described the deposition of non-volatile complexes on to ZnO [IrCl,3- Fe(CN),3- Mn04,- Cr"]. The activation energy of surface potential decay rates agreed reasonably well with calculated values from electrochemistry providing evidence for the existence of these complexes on the ZnO surface. This evidence then allowed further calculations for adsorbate-adsorbent interactions. Hevesi Suli and GyulaiI3 have measured CPD changes on freshly cleaved (010) surfaces of V205. The time between cleavage and measurement was 100-150 s. Oxygen was lost from the surface to leave a structure of VI2O2,.The decay of potential in air of 55% humidity seemed to show three separate rates of change in CPD finally coming to constant CPD. In dry air the rate was slow and in wetter air it was faster. Vacuum conditions produced an even faster rate of change. The presence of water lowered the final value of CPD but dry air raised it again. Inert gases substituted for air gave no change in these results. The total magnitude of charge in CPD in these experiments was 1.3-1.4V, showing that drastic changes take place in this stabilization process. These results showed that freshly prepared catalysts have to undergo a quite long stabilization of surface with the surroundings and that the ambient atmo-sphere can have a marked effect. 2 Nickel Oxide A great deal of attention has been given to the structure of pure and doped nickel oxide with regard to its electrical and catalytic properties (besides the work referred to above3-").A difficulty in following the work reported is the differences in nomenclature chosen for the same process. This was illustrated in l 3 I. Hevesi A. Suli and J. Gyulai Acra Phys. Acad. Sci. Hung. 1970 29 79 228 G. R. Heal references 14-16 from the same conference ; of the following equations : (Ni12+)(O12-) + nLi,O -+ (Nil2+Li,+nLi/A)(0:;,) (13) (Ni12+)(O12-) + 2 L i 2 0 2 -+ (Ni12+Li,+)(O:;n,2~n,2 (14) L i 2 0 -+ LiJNil’ + Li‘ + NiO Li20 + 2LilNil’ + 2Ni0 + 101” (15) (16) (13) and (15) are equivalent as are (14) and (16). and 101” both mean anion vacancy; (NiI2+Li,+) means lithium in nickel lattice positions and LilNil’ implies lithium in nickel vacancies which is the same thing.The first type of equation is from reference 14 the second type from reference 15. Stone16 prefers to draw a two-dimensional version of the NiO lattice showing the vacancies replacements and interstitials in detail. In this review the first type of equation will be used. Nickel oxide exists normally as a non-stoicheiometric p-type semiconductor owing to the uptake of excess oxygen. According to Verwey and De Boer,17 the conductivity is explained by the process The symbols Li/A and Li’ both mean interstitial lithium; (Nii2+)(Ol2-) + ;O2(g) -P (Ni:?,,Ni~,f~,)(O:;,) (17) where is a cation vacancy. The excess oxygen cannot occupy interstitial positions so is at the surface, and nickel oxide is actually a metal-deficient compound.According to the principle of ‘controlled valency”si’9 the number of Ni3 + ions (or positive holes) is changed by doping with ions of different valency (NiI2+)(Ol2-) + 2 L i 2 0 + PO2(& -+ (Ni12+Li,0n)(O:;,) (18) 2 4 where @ is a positive hole and n is small compared with 1. Also Thus by equation (18) oxygen is gained from the atmosphere but by equation (19) it is lost. Also reaction (18) produces more holes or Ni3+ but reaction (19) reduces the number of holes. This effect was demonstrated for NiO at 1200 “C in equilibrium with air.20 14 1 5 16 1 7 1 8 1 9 2 0 P. C. Gravelle G. El. Shobaky and S. J. Teichner Symposium on Electronic Pheno-mena in Chemisorption and Catalysis on Semiconductors Moscow 1968 p.124. A. Bielanski and J. Deren ref. 14 p. 149. R. I. Bickley and F. S. Stone ref. 14 p. 138. E. J. W. Verwey and J. H. de Boer Rec. Trav. chim. 1936,55 531. E. J. W. Verwey P. W. Haaijman and F. C. Romeijn Chem. Weekblad 1948,44,705. E. J. W. Verwey Colloque sur les reactions dans l’etat solid Paris 1948 Bull. SOC. chim. France 1949 D 122. E. J. W. Verwey P. W. Haaijman F. C. Romeijn and G. W. Oosterhout Philips Res. Rept. 1950,5 173 Electrical and Surface Properties of Metal Oxides 229 After experiments involving doping with lithium and measurement of surface area lattice parameter and excess oxygen Bielanski21 has shown that the properties of NiO do not change monotonously with lithium content but that mechanism changes with content.He has proposed two mechanisms for the process [equations (13) and (14) here] and rejected equation (18) because no extra oxygen was incorporated in the solid. Parravano and Boudart22 have proposed a different mechanism for lithium addition: ( N i ~ ~ ~ @ 2 n ) ( 0 2 - ) + f L i 2 0 -+ (Ni:!,Li,f@,)(O,*-) + ;O2(g) Gravelle Shobaky and T e i ~ h n e r ' ~ prepared NiO with doping under vacuum at 25 "C. Surface areas were measured and analysis of stoicheiometry made keeping the solid away from oxygen exposure. The only increase in amount of Ni3+ present was for 10 atom % Li for lower than this amount there was no increase, meaning that mechanism (17) cannot apply. The sample of pure NiO prepared under vacuum had nearly normal stoicheiometry so there would be no vacancies for mechanism (20).The reactions (13) or (14) are possible under vacuum, however. They also measured oxygen chemisorption and found that Li-doped NiO had an enhanced effect and they pointed out that this favours reaction (14) as opposed to (13) because of the anion vacancies produced to take up oxygen. Magnetic analysis showed that all the vacuum samples contained metallic Ni. The Ga-doped samples proved to contain more metallic Ni than pure or lithiated samples. The following mechanism was proposed for this: (NiI2+)(Ol2-) + "Ga203 -+ (Ni~~ni2Gan3f~n,2)(O:;n) + ?Nio + :O2(g) 2 2 (20) 2 (21) This reaction also explained the observed decrease in capacity for oxygen uptake because Ni2+ at the surface was reduced to Nio which migrated to produce nickel crystallites leaving cation vacancies and fewer sites for oxygen adsorption.The mechanism of Hauffe :23 (Nil 2')(012 -) + "Ga2O3 + (Nil2 +Gan3 +mni2)(O ; 3 n i Z ) (22) 2 was dismissed because it did not account for the formation of metallic nickel. Experiments were then performed to allow the samples to equilibrate with oxygen at 250°C. The electrical conductivities were raised by this process, showing that excess oxygen ions associated with Ni3 + ions had been adsorbed or built into surface layers. If the extra oxygen was incorporated by the mechanism : 2 1 A. Bielanski K. Dyrek Z . Khuz J . Sloczynski and T. Tobiasz Bull. Acad. polon Sci., 2 2 G. Parravano and M. Boudart Adv. Catalysis 1955 7 47. 23 K . Hauffe 'Reactionen in und an Festen Stoffen' Springer-Verlag Berlin 1955 p.147. Ser. Sci. chim. 1964 12 657 230 G. R. Heal then the final composition is as proposed by Verwey and de Boer," that is equation (14) plus equation (23) is equivalent to equation (17). Investigations were also made of the chemisorbed oxygen by adsorbing CO on to the surface and removing the resulting CO at 250 "C. Several successive treatments by CO were required to remove all the oxygen in the cases of pure and lithiated NiO. The Ga-doped sample lost all its chemisorbed oxygen in the first adsorption of CO. It would seem that there are very active sites in the case of the lithiated samples owing to anion vacancies. The conclusion as far as doped oxide produced normally in air is concerned is that mechanism (14) is present in the bulk but at the surface reaction (23) follows owing to oxygen adsorption giving the Verwey and de Boer composition in the surface layer.Bielanski and DerenI5 carried out work on Li-doped NiO similar to that of Teichner et a1.,14 but they used more steps of concentration in doping. Since they used a temperature of 1OOO"C in preparation the two sets of results may not be comparable. The Teichner samples made at 250°C under vacuum and analysed under vacuum had areas of 10&-200 m2 g-'. The Bielanski and Deren samples made in air at 1OOO "C had areas of less than 1 m2 g- '. The latter samples were degassed at 400"C to remove chemisorbed oxygen and then analysed. The two lowest-doped samples did not have any excess oxygen; that is no detectable excess Ni3 + ions.This confirms the mechanisms (13) or (14) for the incorporation of lithium. However for 0.13 atom % Li or more excess oxygen was found suggesting that mechanism (19) is now operating. Tei~hner'~ found a slight excess of oxygen only for his 10 atom % Li sample. Several properties of Bielanski and Deren samples showed a maximum in value at 0 . 1 4 . 2 atom % Li followed by a slow decrease with lithium content (Figure 4). These were surface area lattice parameter magnetic susceptibility, work function and catalytic activity. The position of the Fermi potential was found for the bulk by thermoelectric measurements and for surface layers from work function. Initial doping moved both values of Fermi potential down with respect to the conduction level but above 0.13 atom % Li the bulk level con-tinued down while the surface value rose slowly.The order of reaction with respect to oxygen and carbon monoxide in the reaction of these gases was found to vary in a complex way with lithium content. Bickley and Stone16 have reported an interesting series of experiments in-volving doping of NiO with lithium where the NiO is in a solid solution Ni,Mg,-,O with x = 0.01. Under these conditions the NiO should not be capable of showing non-stoicheiometry. This prevents mechanism (1 8) operating but allows mechanism (13) or (14) to do so and the strong chemisorption of oxygen found on the samples suggests mechanism (14). The samples were prepared by evacuating powdered Ni,Mg -,O and Li,O separately and shaking together still under vacuum.An enhancement of uptake of oxygen was found at this stage while still at room temperature. This could hardly be due to the incorporation of interstitial lithium at that temperature (mechanism 13) Electrical and Surface Properties of Metal Oxides 23 1 4170 4160 U f 0.4 0 .o 0 1 2 3 a t % Li I total activity - 0 u -2 -3 -t 0" -1 24 -- E ;; 2 18 16 12 I I I I b 0 1 2 3 at % Li Figure 4 Variation of various physical and catalytic properties of NiO doped with vary-ing amounts of Li20. Curve a in vacuo b in oxygen (1 torr) for changes in work function with Li20 concentration (Reproduced by permission from Symposium on Electronic Phenomena in Chemi-sorption and Catalysis on Semiconductors Moscow 1968 p. 149) Samples heated to 750 "C in U ~ C U O showed an enhanced uptake of oxygen when cooled to 0 "C again.This was supposed to be due to the loss of oxygen by this process reversing upon exposure to oxygen at 0 "C. Teichner and co-workers have conducted a series of experiments to measure differential heats of adsorption using a Calvet micro-~alorimeter.~~ The work involved adsorption of 0 and CO separately and in combination to investigate the reaction between these gases on NiO doped with gallium and lithium. Two probable mechanisms were arrived at for the reaction on the surface of NiO+ 10 % Ga20 made at 250"C the reaction taking place at 30 "C : Mechanism I : CO(g) -+ CO(ads) (27) ( 2 8 ) (29) CO(ads) + 02(g) + Ni2+ + C0,-(ads) + Ni3+ Ni3+ + CO,-(ads) + CO(g) -+ 2COZ(g) + Ni2+ 2 4 P.C. Gravelle G. El. Shobaky and S . J. Teichner J . Chim. phys. 1969,66 1760 1953 232 G. R. Heal Mechanism I1 : 302(g) + Ni2+ + O-(ads) + Ni3+ O-(ads) + CO(g) + Ni3+ -+ C02(g) + Ni2+ (30) (31) Mechanism I1 is faster and controls the rate of reaction under the conditions given. The activity of the doped catalyst made at 250°C was only slightly less that that of pure NiO made at 250 "C. However pure NiO made at 200 "C gave a slower reaction by mechanism I. In the course of the reaction the surface of the catalyst was progressively inhibited by build-up of adsorbed CO,. The activity of the catalyst for this low-temperature oxidation of CO is related to the affinity of surface cations for oxygen. The same reaction was carried out on a Li-doped NiO.In this case mechanism I1 given above was not found to occur but a third mechanism (111) was suggested: CO(g) + 20-(ads) + 2Ni3+ -+ CO,-(ads) + Ni2+ + Ni3+ followed by reaction (29) which is the slowest step in mechanisms I and 111. The existence of anion vacancies on the surface of lithiated NiO is suggested as being responsible for the adsorption of oxygen as 0-(ads). These ions then cause the reaction to proceed via CO,(ads). Thus the adsorbed ions O-(ads) are either formed on cation sites (mechanism 11) or on or near anion vacancies (mechanism 111) and these two species need not be identical. According to another paper,25 adsorption of CO on NiO prepared at 200 "C appeared to be on to two types of site but on raising the preparation temperature to 250 "C the most active sites seemed to disappear.The sites lost were supposed to be labile oxygen ions and the ones left were on or near surface cation vacancies. Incorporation of gallium had little effect on the reaction because it just produced more nickel metal but lithium addition reduced the rate of reaction by removing cation vacancies and creating anionic ones which are inactive for the adsorption of co. These differential heat of adsorption studies showed in general that the NiO surfaces pure and doped are very heterogeneous. Irradiation of NiO followed by the adsorption of oxygen has shown an amount of uptake greater for X-rays than The uptake of oxygen agreed with the shift from stoicheiometry by the creation of Ni3 +. The decrease in concentra-tion of Ni3+ with time of irradiation was not as expected from the theory of Wolkenstein.The application of the t method of study of porosity as modified by Singz7 was applied2* to NiO using argon as adsorbate. The effect of variation in the constant c of the BET equation was first checked and points that would erronously affect the t method could then be left out of the plot. (32) '' P. C. Gravelle G. Marty G. El. Shobaky and S. J. Teichner Buff. SOC. chim. France, 2 6 E. Gisquet and M. Destriau Bull. SOC. chim. France 1969 1455. " K. S. W. Sing Chem. and Ind. 1968 1520. '' G. A. Nicolaon and S. J. Teichner J . Chim. phys. 1969,66 1816. 1969 1517 Electrical and Surface Properties of Metal Oxides 233 The sample of NiO investigated had a BET area of 171.5 m2 g-' but proved to be microporous with an area of only 46 m2 g- ' accounting for adsorption outside of micropores.Adsorption of Ar was also carried out after chemi-sorption of 0, CO and C 0 2 (not at full coverage). The diminution of micro-pore volume (calculated as by Sing29) was approximately proportional to the fractional coverage by chemisorption showing a simple blocking of micropores. A table of values of M,/M,,,* for Ar adsorbed and non-porous &alumina, required for the Sing27 method was given. Fahim and Abu-Shady3' have also investigated the surface area and pore structure of NiO. They followed the decomposition of Ni(OH) to NiO by thermal analysis oxygen content and adsorption characteristics. The highest pore volume and sharpest peak in pore size distribution (at 15 A diameter) was shown by a sample prepared at 300 "C.Samples heated to higher temperatures showed a lower pore volume and surface area as well as a broader pore size distribution and a shift to larger pores. They also applied the t method (un-modified3') but found no micropores in any sample. The Nicolaon-Teichner sample28 was prepared at 200 "C in vacuum while the corresponding Fahim-Abu-Shady sample3' was prepared in air. Also Ar and N respectively were the adsorbates used in the studies. The discrepancy could be due to N not entering very small pores that Ar can enter or the complete absence of micropores in the air-prepared sample. The air-prepared sample had an area (by N adsorption) of only 10.8m2g-' presumably from one of these effects also.Fahim and Abu-Shady3' went on to prepare a sample at 250°C under vacuum which was somewhat comparable with the Nicolaon-Teichner sample,28 but unfortunately they did not do a t-plot. However the area by N adsorption was now 164.1 m2 g-' i.e. near the Nicolaon and Teichner2* value. Adsorption of carbon tetrachloride and cyclohexane on to NiO samples gave reasonable agreement for surface area with N adsorption for all the air-prepared sample^.^' For the 250°C vacuum sample the cyclohexane area was low, suggesting micropores and carbon tetrachloride was reduced on the surface, generating Ni3 + in the solid. This shows the danger of using organic vapours to investigate porous oxides. An extremely good account of the properties of NiO prepared from Ni(OH), has been given by Larkins Fensham and Sanders.32 They have presented results on surface area density magnetic properties and electron microscopy.The conditions of preparation were essentially the same as those of Nicolaon and Teichner,,' but the product only had an area of 100 m2 g - '. Under vacuum it was greenish-yellow but blackened on exposure to oxygen at room tem-perature. This effect could be reversed by heating at 200 "C under vacuum. The density was 6.0 k 0.3 Mg m-3 which is 10 % less than the value for bulk low area oxide. The material was still paramagnetic at 77 K suggesting a particle 2 9 K. S. W. Sing Chem. and Ind. 1967 829. 3 0 R. B. Fahim and A. I . Abu Shady J . Catalysis 1970 17 10. 3 2 F. P. Larkins P. J. Fensham and J. V. Sanders Trans.Faraday SOC. 1970,66 1748. * For a definition of this quantity see ref. 28. J. H. de Boer B. G. Linsen and T. J. Osinga J. Catalysis 1965 4 643 234 G. R. Heal size of less than 8.0 nm. Electron microscopy and diffraction established that the oxide consisted of very thin (2.0 nm in some cases) flakes that have the overall morphology of the parent hydroxide platelets (maximum width between 20 and 200 nm) and an orientation of (11 1) planes parallel to the surface. The flakes contained many irregular-shaped channels about 2.0 nm apart which were separate domains of oxide generally without misorientation across the channel. Actual electron micrographs were included. The decomposition was assumed to involve water loss laterally from the (1 11) planes causing a collapse of the structure and cracking.These cracks might account for the microporous structure. In a subsequent paper33 the same authors examined the adsorption of oxygen on to NiO in the dark and under illumination. In the dark adsorption at low temperatures was fast and increased as temperature decreased. At room tem-perature part of the adsorption was reversible and part irreversible and fast. Above room temperature adsorption increased with rising temperature and was slow. The results were explained by four separate mechanisms of adsorption, A B C and D where all the ions concerned were surface ones. Type A nO,(g) + nBs + (Ni12+)(0,2-) S no,-(ads) + (Ni:!,Nin3+)(O12-) (33) ( 3 4 ) nO,(g) + 2n(as + (Ni12+)(O12-) S 2nO1-(ads) + ( N i ~ ~ ~ N i ~ ~ ) ( O l 2 - ) of equation (4) and are temperature-independent.Types B and D These equations are essentially a more detailed representation of the process Special surface regions + O,(g) S O,(ads) ( 3 5 ) Decreasing adsorption as temperature rises Type c (Nil +)(O -) 6 (Ni +)*(O -) ( 3 4 ) n o + 2 n a + (Ni12+)*(O12-) 2nO;(ads) + (Ni:!,,Ni~,f)(OI2-) (37) Adsorption increases as temperatures rise owing to the activation energy for the production of (Ni2+)*. Adsorption effects upon illumination were quite complex and variable with temperature of operation and pre-treatment tem-perature. A very common effect was desorption followed by adsorption often to enhanced levels. Explanations for the behaviour were put forward. It has been pointed out that uptake of oxygen at high temperatures obeys the law34 where 6 is deviation from non-stoicheiometry.3 3 F. P. Larkins P. J. Fensham and J. V. Sanders Trans. Faraday SOC. 1970,66 1755. 34 C. M. Osburn and R. W. Vest J . Phys. and Chem. Solids 1971,32 1331 Electrical and Surface Properties of Metal Oxides 235 Single crystals were used for electrical conductivity measurements and the highest purity crystals obeyed the law (39) = 9.8 1 0 2 ~ + - ( 1 8 . 6 ~ 1 . 0 k c a l m o l - ' ) / R T h - l c m - l 0 2 However lower-purity samples had higher activation energy and the pressure dependence was nearer 2 Density states and mobility calculations from thermoelectric power led to the conclusion that either a narrow energy band or polaron band conduction mechanism holds.34 In another paper35 the electrical conductivity at a grain boundary in a NiO bicrystal was found to be higher than in the bulk crystal.This was explained as due to impurity concentra-tion at the boundary. This view might invalidate electrical measurements made in powdered samples. Altham McLain and S ~ h w a b ~ ~ have shown that NiO pure or doped with lithium or chromium has different reactivity towards solid reducing agents such as boron germanium and silicon. Differential thermal analysis showed that the Li-doped sample is much more reactive than pure NiO whereas the Cr-doped sample was slightly less reactive. This supported the semiconductor analogy that a p-type oxidizer should be more reactive i.e. receive electrons more easily. This effect could be used to determine the type of non-stoicheiometry in a semi-conductor quickly and easily.The variation with coverage of differential heats of adsorption of hydrogen on NiO samples has been described37 together with a study of the kinetics of the process. A study of the thermodesorption of olefins from NiO has been rep~rted.~' After the first adsorption of ethylene the main desorption peak was also due to ethylene. Second and successive adsorption gave less ethylene back and more product peaks. Activation energies of desorption and isosteric heats of adsorp-tion were calculated and coverage proved to be only 0.084.15 % of the surface. Few conclusions were drawn. A very careful study of the physical conditions of doping NiO with Li,O has been made.39 Lithium and nickel acetate solutions were mixed and the water was removed by a freeze-drying technique.This process ensured complete mixing of the substances on an atomic scale and was compared with conventional evaporation in an oven. The acetates were decomposed at 250 "C under vacuum, cooled exposed to air and then calcinated at various temperatures. Analysis was made of the amounts of Li20 in solid solution free as Li,O and lost by evaporation. For the freeze-dried samples about 500-6OO0C was required to give the maximum amount of Li20 in solid solution and since up to 1000 "C some free L i 2 0 remained the residue must always be washed out by acid. The loss by evaporation varied very much with percentage composition j5 3 6 J. A. Altham J. H. McLain and G.-M. Schwab Z . phys. Chem.(Frankfurt) 1971,74, 3 7 V. E. Ostrovskii Doklady Akad. Nauk S.S.S.R. 1971 196 1141. 3 8 N. Kotsev and D. Shopov J . Catalysis 1971 22 297. 3 9 A. C. C. Tseung and H. L. Bevan J . Material Sci. 1970 5 604. C. M . Osburn and R. W. Vest J . Phys. and Chem. Solids 1971 32 1355. 139 236 G. R. Heal of the starting mixture but was considerable at 1OOO"C and could start at a temperature as low as 400 "C. This is not in accord with Bielanski and Deren,' who prepared samples at 1000 "C and thus risked lower concentration of Li20 in the surface as compared with the bulk. If a high-area solid was required a calcination temperature of no higher than 400°C was indicated. A suitable compromise between rate of incorporation of Li20 and sintering or evaporation effects is suggested as 300 "C.The conventionally oven-evaporated samples showed high Li,O evaporation rates at calcination low concentrations of solid solutions and low surface area. The &-law variation of electrical conductivity has been confirmed4' and for Cr3 +-doped NiO the law becomes &-dependent both results for temperatures above 850°C. These results are said to indicate that only doubly-ionized Ni vacancies can exist owing to the compensation mechanism and the possibility of singly-charged vacancies or excess electrons is excluded. 3 Zincoxide Work on the use of ZnO as a hydrogenation catalyst has been carried out by Teichner et ~ 1 . ~ ' ~ ~ and Kokes et u1.45-50 From electric conductivity measurements it was shown that the surface of ZnO at 250 "C in vacuum loses oxygen (ZnI2+)(Ol2-) 3 n 0 2 ( g ) + (Znf?,,nZno/A)(O~I,) 3 n 0 2 ( g ) + n e - + (Zn:',nZn'/A)(OfI,) (40) where the Zno or Zn' is interstitial in the surface.42 The hydrogen was then supposed to chemisorb to form a covalent bond on the Zn' sites.Zn' + +H2 * (Zn-H)' (41) Heating the oxide in oxygen causes a decrease to zero of catalytic activity towards ethylene hydr~genation.~~ This was called an oxygen poisoning effect. In a later paper,44 a poisoning by ethylene was reported with the formation on the poisoned site of CH=CH / \ C2H4(g) + 2s -P S s + H2k) 40 G. H. Meier and R. A. Rapp Z . phys. Chem. (Frankfurt) 1971 74 168. 4 1 J. Aigueperse and S. J. Teichner Ann. Chim. (France) 1962,7 13. 4 2 J. Aigueperse and S. J. Teichner J . Catalysis 1963 2 359.43 F. Bozon-Verduraz B. Arghiropoulas and S. J. Teichner Bull. SOC. chim. France, 1967,2854. 44 F. Bozon-Verduraz and S. J. Teichner J . Catalysis 1968 11 7 . 4 5 W. C. Conner R. A. Innes and R. J. Kokes J . Amer. Chem. SOC. 1968,90,6858. 4 6 W. C. Conner and R. J. Kokes J . Phys. Chem. 1969,73,2436. 4 7 W. C. Conner and R. J. Kokes J . Phys. Chem. 1969,73 3772. 4 8 W. C. Conner and R. J . Kokes J . Phys. Chem. 1969 73 3781. 49 A. L. Dent and R. J. Kokes J . Amer. Chem. SOC. 1969,91 7207. s o A. L. Dent and R. J. Kokes J . Phys. Chem. 1970,74 3653 Electrical and Surface Properties of Metal Oxides 237 where S denotes a site for adsorption. The mechanism of hydrogenation was given as C2H4(g) + 2s‘ * C,H,(ads) (43) H,(g) 4 2s 2H(ads) (44) C,H,(ads) + H(ads) C,H,(ads) fast (45) C,H,(ads) + H(ads) S C,H,(ads) slow (46) where S and S‘ are different types of site.The kinetics found were quite complex and had to be explained for various temperature ranges by various rate-controlling steps out of the set of reactions. The heterogeneity of the surface seemed to change with poisoning and tem-perature ruling out correlations with other properties of the oxide.44 Studies of the addition of deuterium to ethylene suggested that ethyl radicals form by insertion of ethylene into a deuterium-covered site and that Cr203 and c0304 show a similar mechanism presumably on similar sites leading to C2H4D practically exclu~ively.~~ In this latter work the reaction with respect to hydrogen was found to be first-order as opposed to non-integral orders found by Teichner.Since the use of mixtures of H,-D gave mainly C,H and C2H4D2 not C2H,D the pairs of H or D atoms adsorbed do not exchange with one another.46 This would suggest wide separation of sites for adsorption. Kokes later47 found two types of site for hydrogen adsorption. Type I sites gave fast adsorption and evacuation gave desorption in 15min. Type I1 gave some fast uptake followed by a slow adsorption (up to several days). This slowly taken-up hydrogen also took a long time to come off again. The type I adsorption was shown to be due to the formation of OH and ZnH (by i.r. studies). Adsorp-tion of D on type I1 sites and H on type 1 followed by hydrogenation of ethylene gave practically all C,H, showing only the type I sites were being used (only 1.9% C2H4D formed).An amount of ethylene adsorbed reduced the uptake on to type I1 sites but hydrogen on type I1 sites promoted the reaction. If oxygen was admitted the catalyst was poisoned but only if hydrogen was already ad-sorbed suggesting that water is the poisoning species. All these experiments by Kokes were made at room temperature as opposed to those of Teichner made over a range of temperatures. The variations in order of reaction noted by T e i ~ h n e r ~ ~ could be due to a continuing promotion effect by hydrogen on type I1 sites so ‘initial’ rates only are of significance. Variation in type I1 adsorption with temperature could also account for the variability of Teichner’s results.44 Teichner observed that doping of ZnO with lithium or gallium had little effect on activity and Kokes observed that oxygen did not poison if there was no hydrogen present.It was concluded that non-stoicheiometry is not a requisite for this catalyst. The picture of an active site was investigated in the next paper.48 The (0001) plane has on it at the surface oxide ions with filled dangling bonds and zinc ions in trigonal holes. These ions are not deviations from stoicheiometry but reconstruction of the surface to stabilize the face. These ions are not removed by high temperature oxygen treatment so that the face structure is preserved. A 3 x 3 repeat sequence is found so that sites are not adjacent and only a portio 238 G . R. Heal of the surface will be active. Hydrogen adsorption occurs as H -Zn-0- + H2(g) -Zn-0 I 1 F I (47) The Zn dangling bond is shown shorter because the Zn is under the oxide layer.Adsorption of water vapour which is strong gives H I I -Zn-0- + H 2 0 + -Zn-0-which prevents hydrogen adsorption. Reaction is followed by H H I I H I I H -Zn-0- + -0- Zn-0- + -0-H 7 1 I I -Zn-0- -Zn-0-(49) H I I I I );I I I -Zn-0- + -0- S -Zn-0- + -0- (51) representing migration of the adsorbed hydrogen. In the i.r. bands due to ZnH and OH are seen and as the Zn ion sites become saturated the intensity of the OH band increases and becomes much greater than the ZnH band intensity. This corresponds to reactions (50) and (51) being driven to the right. At lower adsorption the OH band intensity is proportional to the ZnH one.Ethylene was observed to adsorb by interaction of the n-bond with the surface and not by opening of the double bond. This is not likely to occur on the embedded Zn ions but on oxide ions and since coverage is 40%, some will be on oxide adjacent to Zn ions : H ~ C T C H ~ (52) I I H,C=CH + -Zn-0- -Zn-0-H H2C=CH2 I (53) H I H2C=CH + -Zn-0- -Zn--Admission of ethylene to a sample with hydrogen chemisorbed on it decreases the OH band intensity [reverses equations (49) (50) and (51)] and perturbs the ZnH band by the close proximity of ethylene to the Zn-H. Hydrogenation next proceeds by FH3 CH, I I H H 2 C ~ C H 2 -Zn-0- -+ -23-0-yH3 (54) Since deuterium addition gives only C2H4D2 step (54) is irreversible Electrical and Surface Properties of Metal Oxides 239 It was suggested that hydrogen on type I1 sites occupies octahedral sites near to the surface and the slowness of adsorption is due to expansion of the lattice and diffusion in hydrogen.The theories suggested predicted the rate expression found. Later more direct evidence for the intermediate C2H5 -S was p u b l i ~ h e d . ~ ~ ~ ' ~ The isomerization of but-1-ene and cis-but-2-ene has been followed for ZnO catalyst. It is suggested that these reactions proceed by a common intermediate produced by dissociation of a hydrogen and the formation of n-bonded allylic species.' ' The technique of temperature-programmed desorption5' has been applied to the adsorption of H2 and C2H on ZnO. The catalyst was the same as that used by K o k e ~ . ~ ~ ~ ' The solid was treated with oxygen to clean it and then outgassed at various temperatures.After cooling either ethylene or hydrogen was ad-sorbed for times between 15 min and 1 h ; then the temperature was raised at rates between 10 and 20Kmin-'. The main amount of ethylene was weakly adsorbed and proved to be responsible for ethylene-hydrogen reaction. The other form was not hydrogenated at 0 "C. Five forms of chemisorbed hydrogen were found for adsorption temperatures between - 70 and + 300 "C. Only the form first described at about 18 "C reacted with ethylene and must be the type I of Kokes et aL4' However a second form (lost at 43 "C) would be desorbed as type I hydrogen at room temperature. The other three types were lost at 94, 209 and 275°C and must be connected with the type I1 hydrogen of Kokes et Doubt has been thrown on the usefulness of electrical conductivity measure-ments on Zn0.53 Studies of a polycrystalline film with heating to desorb oxygen followed by re-adsorption gives results consistent with necks between crystallites which are effective as barriers.The number of necks is decreased by heating and increased by oxygen treatment. The effect of hydrogen on electrical conductivity has been reporteds4 for temperatures in the range 3&-300 "C. Activation above 300 "C gives an increase in conductivity attributed to excess Zn atoms at the surface. Hydrogen causes this value to increase. The process of formation of H + ions by injection of electrons is said to be greatest at 180 "C but to take place slowly at lower tem-peratures accompanied by fast uptake of non-ionized gas.The non-ionized form is covalently bound hydrogen with maximum uptake at 50°C on to Zn sites. Above 180 "C a third non-ionized form is chemisorbed. 5 ' 5 2 A. Baranski and R. J. Cvetanovic J . Phys. Chem. 1971,75,208. '' H. Watanabe Jap. J. Appl. Phys. 1970,9,418. 5 4 D. Naruyana V. S. Subrahmanyam Jadish Lal. M. Mahmood Ali and V. Kesavulu, A. L. Dent and R. J. Kokes J . Phys. Chem. 1971 45 487. J . Phys. Chem. 1970,74 779 240 G. R. Heal The process H2 G 2H(ads) 2H+(ads) + 2e- (57) suggests conductivity will vary as a = k[p,,]+ which was found. A study has been made of e.s.r. signals and electrical cond~ctivity.~~ It was shown that the e.s.r. signal is due to conduction band electrons not ones in donor states.The number of electrons transferred per oxygen atom adsorbed depended upon coverage that is the chemisorbed species is controlled by coverage. The suggestion has been made that adsorbed foreign species on a semiconductor will provide surface states which will control the surface Fermi Filled and empty states have to be added i.e. a substance in two different oxidation states. The differing effects of one-equivalent and two-equivalent species have been distinguished. The latter are chemicals with two adjacent stable oxidation states (i.e. separated by only one electronic charge). The former type has two stable oxidation states but an unstable state also between the stable ones. The Fermi level was then shown to be fixed by the ratio of the concentrations of the two oxidation states placed on the surface even if the deposit is n~n-uniform.~~ The effect has been used in studies of photodamage to ZnO powders.57 E.s.r.measurements showed for un-irradiated samples that one peak due to conduction electrons (g = 1.96) rose in intensity above 500 K owing to the desorption of oxygen and perhaps water. The effect was caused by the excess non-stoicheio-metric zinc in the lattice perturbing the electric fields for normal conduction electrons. On exposure to oxygen the effect was reversed. When iron cyanide ([Fe3']/[Fe2'] = 1) was deposited on the surface the spin concentration observed fell to zero above 500 K owing to the process Fe3+ + e(g 1.96) .+ Fe2+ (59) When samples were subjected to U.V.irradiation the spin concentration rose if pure ZnO or low concentrations of cyanide were used. If the iron concentration was above lo-* moll-' (coverage monolayers) then there was no effect produced by irradiation i.e. all electrons released were captured by the ferric ions. Preliminary results showed that the suppression of spin-concentration changes was a minimum for [Fe3+]/[Fe2+] = 1. There was also some evidence that dislocations of ZnO produced mechanically caused larger increases in spin concentration by irradiati~n.'~ The same effect was also studied with the solid exposed to various ratios of oxygen to hydrogen pre~sure.~' Pure ZnO and low concentration of cyanide samples were very sensitive to changes in this ratio the spin concentration falling 5 5 5 6 S.R. Morrison Surface Sci. 1968 10 459. 5 7 K. M. Sancier Surface Sci. 1970 21 1. '* J. P. Bonnelle and M. Guelton Surface Sci. 1971 27 375. M. Scidka K. M. Sancier and T. Kwan J . Catalysis 1970 16 44 Electrical and Surface Properties of Metal Oxides 24 1 as oxygen pressure rose. As the amount of cyanide increased the solids became more and more insensitive to oxygen. For concentrations greater than 5 x moll- the spin concentration remained constant and this was referred to as anchoring the Fermi level at one value ([Fe3+]/[Fe2+] was again unity). The effect of this was important in the hydrogen oxidation reaction because (a) The concentration of the intermediate 0- could be increased without changing the surface charge by 30 + e - + 0- Fez+ + Fe3+ + e - (60) (b) It should be possible to optimize the position of the Fermi level to maximize the catalytic rate.4 Other Studies in Electrical Conductivity In Li-doped COO a large change of conductivity with temperature was found,59 due almost entirely to a change in charge-carrier concentration and not in mobility. The explanation given is that the Co3+ neighbouring a Lif ion is in a low-spin state. The Co3+ in the rest of the lattice is in a high-spin state and energy must be added to convert the low-spin to high-spin before electron transfer can take place with a neighbouring high-spin Co2 + (conductivity). A change of p-type to n-type behaviour in pure and doped COO has been reported,60 but only at temperatures of about lo00 "C in an atmosphere of CO and COz.The surface adsorption of oxygen on to MnO seems to be of the same type as in the case of NiO namely Mn is removed to the surface leaving doubly charged cation vacancies and four holes.61 O,(ads) 2Mn0 + 2Mn, 2Mn * Mn,,. + 4 0 As oxygen pressure above the solid is raised the conductivity first falls then rises owing to a low concentration of electrons of high mobility which are later replaced by holes of lower mobility. The conduction of metal oxides has been reviewed recently and it was pointed out their electrical properties are not well understood mainly because of lack of care in their characterization or preparation.62 It has been pointed out that simple donor-acceptor techniques used to try to explain the conduction of NiO A calculation has been developed allowing for such effects as screen-ing covalency crystalline-field and overlap and leads to band structures which are in agreement with experiment.Studies of tin dioxide show that it always contains Sn2+ and Sn'; thus it is an n-type semicond~ctor.~~ Reduction with hydrogen produces SnO but with 5 9 A. J. Bosman and C. Crevecoueur J. Phys. and Chem. Solids 1969,30 1151. 6 o M. Gvishi and R. S. Tanhauser Solid State Comm. 1970 8 485. 6 1 6 2 J. M. Honig IBM J. Res. Develop. 1970 232. 6 3 D. Adler IBM J. Res. Develop. 1970 261. 6 4 B. P. Kryzhanovski and A. V. Kruglova Russ. J. Phys. Chew. 1971 45 144. M. O'Keefe and M. Valigi J. Phys. and Chem. Solids 1970 31 947 242 G. R. Heal some disproportionation into Sn4+ and Sn’. These reactions should increase the conductivity but in fact it fell to 0.1 % of its original value.This was attributed to disturbance of the original SnO lattice. Treatment by air then caused even more disproportionation and conductivity rose sharply. The re-oxidation of Sno and Sn2 + was slow owing to diffusion of oxygen into the lattice. The conductivity of V205 has been accounted for by the model of a dislocation perpendicular to the b-axi~.~’ Along the dislocation plane are interstitial oxygens. Each of these is associated with a V-V trapping pair and conduction is by hopping from one pair to the next. The 02- species will be mobile at high temperature and may account for the properties of V205 as an oxidation catalyst. A correlation between an equation for conductivity based on absolute reaction rate theory has been tested for oxides of the p-type.66 The mechanism proposed is the one generally used but oxygen is supposed to adsorb first on the site of the doping ion at the surface to form a complex.The n-type oxides have been dealt with in a similar way. The species responsible for conduction is Zn+ and the bimolecular reaction of this with Zn2+ is the starting point for the con-ductivity theory.67 It is predicted that variation of conductivity with oxygen present should follow pressure to the power of $ which is indeed the case. The testing of several specific reactions over semiconductor catalysts has been reported to see if the theories suggested work in practice.67 Ramaswamy Ratnasamy and YeddanapallP have tested an n-type (ZnO), a p-type (NiO) and an amphoteric oxide (Cr203) for the dehydrogenation and dehydration of propan-2-01.They doped the solids also with S042- using sulphate solutions. The pure ZnO and NiO gave only acetone but as doping of either increased more propene was formed. The addition of hydrogen or acetone (the product) had little effect on the dehydrogenation reaction. The progressively-doped samples of both oxides showed a decreasing electrical conductivity. Thus SO, - increases the Fermi level for NiO but suppresses it for ZnO. In the presence of the propan-2-01 vapour the electrical conductivity of NiO decreased while that of ZnO increased. This was attributed to build-up of acetone on the NiO surface on the one hand and reduction of the catalyst by the alcohol during the reaction in the case of ZnO.Catalytic activity fell for both samples as the Fermi levels were changed. According to Wolken~tein,~’ reactions on p-type catalysts are suppressed by raising the Fermi level and, on n-type lowering the level also suppresses the reaction. This is in accord with the results. Cr20 was reduced by hydrogen or oxidized by air before being used to dehydrogenate /I-pinene to p-cymene. The reduced n-type was more effective as might be expected for an acceptor reaction on a high Fermi level solid. 6s J. H. Perlstein J . Solid State Chem. 1971 3 217. 6 6 0. K. Davytan and E. T. Misyuk Russ. J . Phys. Chem. 1969,43,172,816 1971,45,55. 6 7 0. K. Davytan Russ. J . Phys. Chem. 1971,45 197. 6 8 A. V. Ramaswamy F. Ratnasamy and L. M. Yeddanapalli J .Indian Chem. Sac., 6 9 F. F. Wolkenstein ‘The Electronic Theory of Catalysis on Semiconductors’ Pergamon, 1971 48 145. New York 1963 Electrical and Surface Properties of Metal Oxides 243 Two V 2 0 5 samples one made from vanadyl oxalate the other from ammonium metavanadate have been found to have different catalytic properties and con-ductivities the first one having the higher conductivity and activity.70 It also had higher surface area magnetic susceptibility and larger e.s.r. signal owing to the presence of V4+. The conductivity decreased regularly with oxygen chemi-sorption. Thus it would seem that there are more anion vacancies and quasi-free electrons in the first sample and activity is paralleled by electrical properties." A study has been made of high purity ferric oxide doped with small amounts of magne~ium.~' It has been shown that this n-type semiconductor is converted into p-type by the doping.72 The properties of the n-type and doped n-type oxide were investigated earlier.73 In the paper de~cribed,~ measurements were made of d.c.resistance Seebeck voltage and electron probe microanalysis. The conductivity of the doped samples was always greater than that of the pure Fe203 and showed for a plot of log(conductivity) us. 1/T two linear decreasing portions separated by a plateau. The low-temperature linear portion was found to be appreciably influenced by grain boundary effect and firing at higher temperatures raised the conductivity. In the plateau region above 400-450°C it is believed *at conductivity is relatively free from grain boundary effects.Since the mobility of carriers must still rise in this region the concentration of carriers must remain relatively fixed with respect to temperature. In the higher temperature region, above 800 "C two possible mechanisms for conduction are suggested. Intrinsic Fe3+ + 02- -+ Fez+ + 0-Oxygen loss lattice -+ 4xFe2+ + xO,(g) The process then involves n-carriers or electrons jumping to other cations and p-carriers or holes on oxygen ions (0-) jumping to neighbouring anions. In the two higher temperature regions Oobs % p p e p + On where cobs is the total observed conductivity p p is the mobility and p the number of p-carriers and on is the conductivity of the pure oxide (n-type). The pure oxide shows little contribution to conductivity of the doped oxide in the middle temperature region i.e.c, 'v 0. Then cobs should be proportional to p which should itself be proportional to the amount of Mg added. This result was found for up to 0.2 % Mg. (65) The Seebeck voltage 8 is related to p approximately by where N o is number of available states taken to be the number of anions per 'O S. K. Bhattacharyya and P. Mahanti J . Catalysis 1971 20 10. 7 2 7 3 D. Cormack R. F. G. Gardner and R. L. Moss J . Catalysis 1970 17,219. R . F. G. Gardner R. L. Moss and D. W. Tanner Brit. J . Appl. Phys. 1966 17 5 5 . R. F. G. Gardner F. Sweet and D. W. Tanner J . Phys. and Chem. Solids 1963 24, 1175 1183 244 G. R . Heal cm3 i.e. 6 x ~ m - ~ . This relationship was also obeyed up to 0.2% Mg.It was believed that at higher Mg concentrations the spinel magnesium ferrite, is formed. The electron probe microanalysis confirmed the presence of this material as a separate phase. The samples were exposed to methanol plus air and the conductivity of the pure Fe203 rose owing to the injection of more electrons. The conductivity of the doped samples fell consistent with the injected electrons destroying some of the holes. Since where Ar-methanol was used the effect was reversible oxygen loss could not be responsible. In a second paper,74 two catalytic reactions were investigated on the various Fe203 surfaces. The first reaction was the decomposition of N,O. As would be anticipated for this rea~tion,~’ the addition of Mg lowered the activation energy.However above 0.2 % Mg the activation energy rose again to near the value for pure Fe203. Presumably the ferrite was capable of withdrawing p-type carriers from the bulk of Fe203. The second reaction was the conversion of methanol into formaldehyde. A maximum in activity and selectivity was seen for the 0.2 % Mg sample. If the catalyst was used for methanol conversion then re-used for N 2 0 decomposition activation energy for the latter reaction was higher than previously. This was taken to mean that the reducing conditions of methanol had encouraged the formation of the separate spinel phase during catalysis conditions. A study of doping of the insulator y-A1203 by lithium and titanium has been reported. 7 6 The correlation was made between conductivity and activity towards propanol decomposition.The variation in conductivity as a function of concentration of MOO on A1203 has been mentioned.77 The state of the electronic theory of catalysis was well reviewed at a’symposium in M o s c o w . ~ ~ - ~ ~ A variation of the usual electronic theory of catalysis has been provided by Lee.83 He finds a number of facts in the results of catalytic reactions on semi-conductors that cannot be explained by or are contradictory to the electronic theory of catalysis. The suggestion is put forward that electron-hole pairs are produced in the bulk of the catalyst by thermal effect or photo effect. The two species migrate to the surface and take part in charge-transfer reactions. The rate of the process may then be limited by the rates of charge transfer surface reaction and electron-hole recombination via new states formation and charge l4 D.Cormack R. J. Bowser R. F. G. Gardner and R. L. Moss J . Catalysis 1970 17, 230. 7 5 F. S. Stone ‘Chemistry of the Solid State’ ed. W. E. Gomer Interscience New York, 1955 p. 367. 76 H. Pscheidl et al. Z.phys. Chem. (Leipzig) 1968 239 185; 1969 240 145 161; 1970, 243 61 69; 1970,244 128. l 7 K. M. Gafurov M. A. Magrupov and A. Y. Khamidov Uzbek. khim. Zhur. 1969, 13 67. 7 8 K. Hauffe and R. Stechemesser ref. 14 p. 1 . 7 9 Th. Wolkenstein ref. 14 p. 28. M. Tomasek and J. Koutecky ref. 14 p. 41. 8 1 0. Peshev ref. 14 p. 56. 8 2 J. F. Garcia de la Banda ref. 14 p. 83. 8 3 V. J. Lee J . Catalysis 1970 17 178 Electrical and Surface Properties of Metal Oxides 245 transfer.Equations for these steps were developed and found to fit the facts quite well. As an example in the Hz-D2 exchange over germanium intrinsic germanium was an order of magnitude more active than n- or p-type germanium. On the old theory it was expected that the activity would change continuously to follow change in electron (or hole) concentration. On the new theory the maximum activity would be expected for pure germanium because this sample has the highest concentration of n- and p-type carrier both of which are required for the charge-transfer reactions. It is immaterial whether a reaction inter-mediate is a donor an acceptor or both. The process was said to be analogous to electrolysis. A result that fits the theory very well is for the oxidation of CO over Cu,O pure and doped with sulphur or antimony.The voltage drop instead of resistance is given as well as rate of reaction (Figure 5). The phenomena of photo effects in chemisorption have received some atten-ti~n.'~-'' The suggested mechanism is that upon irradiation a new electronic equilibrium is rapidly set up followed by a slower relaxation to a new adsorption equilibrium. Thus the effect may be photoadsorption or photodesorption or both when several surface species are involved.' If ZnO is in the reduced state, photodesorption of oxygen takes place but in an oxidized sample photo-adsorption takes place.' The reverse effect of adsorboluminescence has been rep~rted.'~ Apparatus for the measurement of the Seebeck coefficient in oxides has been described." As an alternative to Seebeck coefficient measurement for finding carrier con-centration Hall coefficient measurement has been suggested.' 1-93 The method involved pressing a powder in a special die which allowed contacts to be in-corporated.A dual ax. mode of measurement was used. Correlations were made between the results of Hall effect and conductivity measurements and cata-lytic activity. This method has been severely criticized94 from several points of view: (a) The theory linking carrier concentration at the surface and Hall coefficient was worked out for long thin crystals not for a polycrystalline mass of powder. ( b ) No correct way of calculating current density in a powder compact has been given. (c) There is doubt as to the origin of the electrons involved in the bonding of oxygen to the surface which throws doubt on the value of Hall effect measure-ments.8 4 W. M. Richey and J. G. Calvert J . Phys. Chem. 1956 60 1465. 85 E. Molinari ref. 14 p. 167. 86 T. Kwan ref. 14 p. 184. '' F. Steinbach ref. 14 p. 196. *' M. Teodorescu and E. Segal Rev. Roumaine Chim. 1970 15 371. 8 9 S. Z . Roginsky ref. 14 p. 212. 9 0 A. Ionescu A. Dinu and M. Ionescu Rev. Chim. (Roumania) 1970 21 9. 91 H. Chon and C. D. Prater Discuss. Faraday SOC. 1966 No. 41 p. 380. 9 2 H. Chon and J . A. Pajares J . Catalysis 1969 14 257. 9 3 H. Chon C. D . Prater and J. A. Pajares Anales Fiz. 1969 65 325. 9 4 R. I . Holliday and M. Pitt J . Catalysis 1970 17 121 246 G. R. Heal 800 400 0 400 800 - sulphur Antimony -0.7 0.6 0.5 Q e al ul 0.4 9 0.3 cu,O Impurity composition p.p.m.(atomic ratio) Figure 5 The effect of S and Sb concentration in Cu,O on the rate of the photochemical CO formation and on the electrical properties of samples. The voltage drop was measured for a current density of 400 mA in-, (Reproduced by permission from J . Phys. Chern. 1956,60 1465) (d) The a.c. method used may suffer from probe pick-up causing erroneously high Hall voltages. A new type of experiment has been devised to throw light on the electronic structure of semicondu~tors.~ This is known as Thermally Stimulated Electron Current measurement. A sample was irradiated with energy higher than the band gap (u.v. lamp) at a low temperature (77.4K). Electrons will then over-populate the various trapping levels.On warming the sample at a regular rate peaks were observed in conductivity and photoemission. The peaks may be used to give a value of the energy of the individual electronic state as well as occupancy of the trapping levels from area under the peaks. Some of the levels have been identified but others are unknown (when ZnO was examined). 5 The State of Adsorbed Oxygen and Hydrogen E.s.r. evidence has been used to show that if ZnO is treated with oxygen the species O2 - is formed but under reducing conditions (hydrocarbon or hydrogen ’’ T. J. Gray and M. Lowery Discuss. Faraday SOC. 1971 No. 52 Electrical and Surface Properties of Metal Oxides 247 gas) 0 - is found.96 The e.s.r. signals produced by these species were accompanied by a decrease in the signal at g = 1.96 (due to Zn' or oxygen vacancy).Zinc-metal-treated ZnO gave peaks due to 0- and 0,- but they occur very close together at g = 2.042 and g = 2.039 respectively. Similar results were found for TiO .97 More evidence 98-103 ha s appeared for the species of oxygen on several oxides being 02- using e.s.r. measurements and oxygen enriched with 1702. Oxides studied include TiO SnO MgO ZnO and Fe203. However 0- was made on a MgO surface by the action of N,O and was found to occupy two or more types of site.lo4 Addition of oxygen produced a new e.s.r. signal thought to be due to the production of 03-. Heating then converted 0,- into 0,-. Hydrogen converted the 0- into OH- plus a trapped electron. lo4 On Cr03-Si02 catalysts reduced with NH, the form of oxygen was again 02- but if the samples were reduced with H2 or CO and oxygen was adsorbed, first at room temperature or - 78 "C followed by further adsorption at - 196 "C, new signals appeared.lo5 These were assigned to 04- ions.The sites for oxygen adsorption were also discussed. The exchange rate of "0 with l60 in the surface has been measured on V,O,-MOO catalysts. lo6 In contradiction for lanthanum-cerium oxides no exchange with the surface was found nor was there any reaction 1 6 0 2 + 1802 2 l 6 0 l 8 0 . The latter result proves that 0,- in the surface is not involved in oxidation reactions.'07 Oxygen chemisorbed strongly on NiO has been estimated by a thermo-desorption technique. The amount adsorbed rose upon irradiation by X-rays but came off at a slightly lower temperature showing weaker binding.'" Gas chromatographic determination of chemisorbed hydrogen on iron oxide, nickel oxide and copper oxide seems to show only one specie^.'^' However, similar experiments on Cr,O showed four types of hydrogen as (i) Molecular hydrogen mainly at - 195 "C (ii) a small amount of chemisorbed hydrogen which is inactive for H,-D exchange (iii) adsorbed hydrogen acti-96 M.Codell J. Weisberg H. Gisser and R. D. Iyengar J . Amer. Chem. SOC. 1969 91, 7762. 9 7 I. D . Micheikin A I. Maschenko and V. B. Kazonski Kinetika i Kutalir 1967 8, 1363. 9 8 C. Naccache P. Meriaudeau M. Che and A. J. Tench Trans. Faraduy SOC. 1971,67, 506. 9 9 P. Meriaudeau C. Naccache and A. J. Tench J . Catalysis 1971 21 208.l o o A. J . Tench and T. Lawson Chem. Phys. Letters 1971,8 177. l o ' A. J. Tench and T. Lawson J. Phys. Chem. to be published. l o 2 M. Che J. Vedrine and C. Naccache Bull. SOC. chim. France 1970 3307. l o 4 A. J. Tench and T. Lawson Chem. Phys. Letters 1970 7 459. l o 5 Y. Doi Kogyo Kagaku Zasshi 1971,74 803. l o 6 M. Blanchard G. Longuet G. K. Boreskov V. S. Muzykantov and G. 1. Panov Bull. SOC. chim France 197 1 8 14. l o ' G. V. 'Antoshin Kh. M. Minachev and M. E. Lakhuary J . Catalysis 1971 22 1. J. Poublan M. Le Diraison and M. Distrian Compt. rend. 1971 272 C 1741. l o 9 Y. Shigehara and A. Ozaki J. Chem. SOC. Japan 1970,91 940. ' l o Y. Shigehara and A. Ozaki J . Chem. SOC. Japan 1971,92 297. A. A. Davydov and U. M. Shchekochikhim Kinetika i Kataliz 1971 12,803 248 G.R. Heal vated at higher temperature and (iu) the hydrogen of surface hydroxyl. Type (ii) gave isotopic exchange above -75 "C and types (iii) and (iv) above 300 "C. Type (iu) seems to give reduction of excess oxygen above 100°C followed by dehydration with the hydrogen stream at 200-500"C. The chromic ion then exposed seems to be occupied by the type (iii). Temperature-programmed desorption of hydrogen from alumina gave at least five different states of chemisorbed species," four of which were investigated further for isotherms or rates of adsorption and desorption. The weakest type of adsorption H(1) (rapid at - 78 "C) fitted the dissociative Langmuir isotherm. At room temperature H(I1) and H(II1) were major states. H(I1) gave a rapid uptake but H(II1) was slow in adsorption.Type H(V) was slow and only appeared above 250°C. The last type H(IV) only appeared in one result and was not investigated further. Types H(I) H(III) H(IV) and H(V) were thought to share all or part of the sites which are the surface defects of alumina. Isotopic exchange with D2 only occurred with type H(1). 1.r. evidence has confirmed the existence of Zn-H and Zn-OH when hydrogen is adsorbed onto ZnO at low temperatures.'12 Isotopic exchange studies showed that the reaction proceeds via chemisorbed hydrogen and molecules in the gas. 6 Miscellaneous Studies If semiconductor oxides are used for surface property studies in the form of a fine powder note should be taken of the effects produced by degree of disper-sion."3 In large crystals where dimensions 1 >> L (where L is the screening distance) the state of the bulk affects the state of the surface but the screening effect insulates the bulk from the influence of surface charge.When 1 < L the bulk phase becomes sensitive to surface changes. References to this effect being noticed were given."3 Formulae were developed to show that the sign of the effect of dispersion on a catalytic rate varied with type of reaction (acceptor or donor) and sign of the surface change. It would be very useful in catalytic reaction studies to have some measure of active sites. Since the adsorption of CO or H,O on to oxides blocks the surface for reactions such as isotopic mixing in ethylene it has been suggested that CO uptake should give such a mea~ure."~ A study of exo-electron emission from various oxide surfaces has been made.'I5 The samples were irradiated with electrons (1.5 keV) and the after-emission was measured with an electron multiplier.The centres responsible for emission were either OH groups forming electron localization levels or levels formed by chemi-sorbed oxygen. The chemisorption of oxygen was shown to increase the emission of ZnO. The effect of repeated irradiation (up to 15 times) was noted together Y . Amenomiya J . Catalysis 1971 22 109. 1971,67 1519. 0. Peshev Russ. J . Phys. Chem. 1970,44 205. A. Ozaki and K. Tanaka J . Catalysis 1971 20 422. I . V. Krylova and I. A. Rodina Russ. J . Phys. Chem. 197 1 45 660. 'I2 S. Naito H. Shimizu E. Hagiwara T. Onishi and K. Tamaru Trans.Faraday Soc. Electrical and Surface Properties of Metal Oxides 249 with vacuum treatment at various temperatures. A parallel series of thermo-desorption studies has been made.'16 Oxides could be divided into two types: (a) Dielectric and n-type semiconductors MgO ZrO TiO ZnO. Repeated bombardment of these led to an increase in emission followed by a decrease. Heat treatment in vacuum for 5 h did not destroy the emission capacity. ( b ) p-type semiconductors (NiO C U ~ ) . The emission intensity decreased after repeat runs and heating for 5 h at 450 "C caused a sharp fall in value. The sample of Cr203 (intrinsic semiconductor) had properties between (a) and (b). The gases evolved upon irradiation were analysed and type (a) gave off > 50 % water but (b) gave off mainly CO .About 50 % of the water from group (a) was re-adsorbed in cooling of the solid. It was suggested that type (a) has hydroxy-groups and physisorbed water. The physisorbed water prevented emission and a rise was seen when the water desorbed. Further irradiation caused loss of hydroxy-groups leading to a decrease in emission. Type ( b ) had chemisorbed oxygen which was caused to desorb or convert into lattice O2 - by irradiation, thus decreasing emission. It was noted that emission was determined not by the specific surface of the oxides nor by the width of the forbidden gap nor by conductivity factors but only by the adsorption of gases as chemisorbed species.' l 5 Papers that have appeared recently dealing with investigation of the porous structure of oxides include those given in references 117-1 19.A review of atomic species on surfaces as intermediates in catalysis has been given by Wagner.'20 Gravelle and Teichner12' have published a very long study of carbon monoxide oxidation on NiO. An attempt has been made to correlate the rate of hydrocarbon oxidation over oxides with their heats of formation per oxygen atom.', It was pointed out that the heats of formation do not represent metal-oxygen bond energies but rather the band gap values for these substances. This idea corrects a previous mis-conception.' 2 3 The catalytic activity is thus interpreted in terms of electronic conductivity not a bond strength. On the other hand other workers have tried to relate activity with the Gibbs free energy of oxygen release,'24 but this correlation may suffer from the same fault as that criticized above.7 Comments It emerges from the papers reviewed that before a study of the electrical or catalytic properties of an oxide is undertaken a great deal of work on the ' I 6 1. V. Krylova and I . A. Rodina Russ. J . Phys. Chem. 1971 44 2625. I ' J. D. Carruthers D. A. Payne K. S. W. Sing and L. J. Stryker J . Colloid Interface Sci., 1971 36 205; Discuss. Faraday SOC. 1971 No. 52. D. Dollimore and G. R. Heal J . Colloid Interface Sci. 1970 33 508. C. Gravelle and S. J. Teichner Ado. Catalysis 1969 20 168. 'I8 G. D . Parfitt D. Urwin and T. J. Wiseman J . Colloid Interface Sci. 1971 36 217. ' I 2 O C. Wagner Adv. Catalysis 1970 21 323. 1 2 ' A. K. Vijh and P. Lenfant Canad.J . Chem. 1971,49 809. 1 2 3 Y . Morooka and Ozaki J . Catalysis 1966,5 116; 1967,7,23. l Z 4 W. M. H. Sachtler G. J. H. Dorgelo J. Fahrenfort and R. J. H. Voorhoeve Rec. Trav. chim. 1970 89 460 250 G. R. Heal characterization of the solid must be carried out. The work in reference 39 shows that when doping is carried out extreme care must be taken to ensure that only a uniformly doped single phase is being produced. The next step should be the stabilization of the solid with respect to vacuum or an active gas over several days if need be. Chemical analysis can be very useful in determining non-stoicheiometry and defects and it has shown that the mechanism of doping with foreign ions is not as simple as was thought at one time. Electrical measurements have often been made on compressed powder because of the ease of measuring the surface properties of such a powder. This has been criticized because of the doubt as to the effects at the points of contact between particles which may lead to incorrect laws and activation energies. It would seem that the use of single crystals or thin films of oxide should be pre-ferred for such measurements. The most satisfactory electrical measurement seems to be that of surface potential in low ambient gas pressure conditions. These measurements together with e.s.r. seem to explain satisfactorily the changes seen in surface species but of course do not directly follow changes in the reservoir of charge carriers in the bulk of the solid. Even when so much work has been carried out on one substance such as NiO, very few workers have chosen to use the same conditions of preparation and testing as previous workers. This means that results are never quite comparable. If standard conditions could be agreed then any discrepancies could be discussed as the effect of trace impurities sources of raw material ageing etc

ISSN:0069-3022    

DOI:10.1039/GR9716800221

出版商:RSC    

年代:1971

数据来源: RSC

摘要:

PART II INORGANIC CHEMISTRY 12 Introduction By D. W. A. SHARP Department of Chemistry University of Glasgow Glasgow G72 800 and Department of Chemistry Auburn University Auburn Alabama U.S.A. The general form of the 1971 Annual Reports (Vol. 68) on Inorganic Chemistry is essentially the same as that of Volume 67 except that the system of numbering of references in the section on the Typical Elements has been changed to allow greater ease of manuscript preparation. Under the new system the sequences of numbers start at 1 at the beginning of Groups I IV and VI; there is no cross-referencing between these sections using a common reference. Under each element or section the aim has been to work successively across the Periodic Table. Once again the aim of the authors has been to provide a selective cover of what appears to them to be the most important current developments in their field rather than to give comprehensive cover.It must be noted by readers that with the various industrial disputes which have affected the postal services during 1971 the cover corresponds less to a calendar year than is usual and is not completely consistent between sections. It is hoped to achieve a more rational basis for 1972. With the large amount of literature covered it is difficult and extremely sub-jective to pick out particular areas of what appear to be major importance. It is clear that interest in organometallic chemistry continues to increase rapidly, being now the most active area for most elements of the Periodic Table. Of major importance has been the resolving of differences over the dissociation energy of fluorine (p.354) which affects markedly many other thermodynamic quantities. The year has seen the isolation of several very simple species including hypo-fluorous acid,' HOF and difluorodioxocarbonates,' M,CO,F . In transition-metal chemistry there are already major developments in the chemistry of nitrogen fixation and there is a great potential for the chemistry of the new super-heavy elements which may become available during the next decade (pp. 365 and 366). Transition-metal amides and alkoxides e.g. Cr(NPr',) sometimes show apparently great molecular simplicity which is certainly not reflected in the bonding (p. 406). Metal-metal bonds are now commonplace throughout the transition series and many new examples are given in this year's Annual Reports.It is apparent that the star of anomalous water is on the decline (p. 338). New journals containing inorganic chemistry continue to appear3 and to pose problems to chemists faced with shrinking budgets. Many reviews have been M. H. Studier and E. H. Appelman J . Amer. Chem. Soc. 1971 93 2349. E. Martineau and J. B. Milne Chem. Comm. 1971 1327. J . Co-ordination Chem. ; J . Fluorine Chem. ; Phosphorus; Synthesis in Inorganic and Metal Organic Chem 252 D. W. A . Sharp published during the year and amongst those covering more general topics (specific reviews are mentioned elsewhere in the Report) are an annual biblio-graphy of structural determinations on inorganic compounds ;4 volumes of Gmelin on Silver Iron Tantalum Niobium Lead Tin Potassium and Carbon ; preparative solid-state chemistry ;’ inorganic electrosynthesis in non-aqueous solvents ;6 isosbestic points ;7 single crystal and gas-phase Raman spectra ;8 Mossbauer spectra and chemical bonding ;9 X-ray emission spectroscopy ; O thermodynamics of metal complexes and ion-pairs ;ll Madelung constants and their use as a guide to structure;12 the Jahn-Teller effect;13 the vitreous state;14 the ionization of covalent compounds ;’ ’ multiple bonding and back co-ordina-tion ;‘ reactivity ofambidentate ligands ; l 7 hydrogen-bond theory ; l8 isoelectronic series of organophosphorus organosilicon and organoaluminium derivatives ; * nitrato-complexes ;” phthalocyanines2 and metalloporphyrins ; 2 2 O X O - ~ ~ and hydr~xy~~-complexes ; the bond character of P-diketonates2 and the stereo-chemistry of bis-chelated metal@) complexes ;26 and metal-~ulphinates.~’ Finally some suggested abbreviations for non-chelating extractants have been published ;” in this and in other areas of inorganic chemistry urgent international action on nomenclature is necessary.Inorganic chemistry suffered a great loss in 1971 through the death of Sir Ronald Nyholm. He contributed greatly to the work described year by year in these Reports. Co-ordination Chem. Rev. H. Schafer Angew. Chem. Internat. Edn. 1971,10,43. B. L. Laube and C. D. Schmulbach Progr. Inorg. Chem. 1971,14,65. T. Nowicka-Jankowska J . Inorg. Nuclear Chem. 1971 33 2043. G. A. Ozin Progr. Inorg. Chem. 1971 14 173.R. L. Mossbauer Angew. Chem. Internat. Ed. 1971,10,462. G . H. Nancollas Co-ordination Chem. Rev. 1970 5 379. R. Hoppe Adv. Fluorine Chem. 1970 6 387. J. A. Creighton Essays in Chem. 1971 2 45. l o D. S. Urch Quart. Rev. 1971 25 343. l 4 Discuss. Faraday SOC. 1970 No. 50. l 5 V. Gutmann Angew. Chem. Internat. Edn. 1970 9 843. l 6 L. D. Pettit Quart. Reu. 1971 25 I . S. A. Shevelev Russ. Chem. Rev. 1970 844. l 8 M. L. Huggins Angew. Chem. Internat. Edn. 1971 10 147. l 9 H. Schmidbaur Adv. Organometallic Chem. 1970 9 260. 2 o C. C. Addison N . Logan S. C. Wallwork and C. D. Garner Quart. Rec. 1971 25, 289. 2 1 A. A. Berlin and A. I. Sherle Inorg. Macromol. Rev. 1971 1 235. 2 2 P. Hambright Co-ordination Chem. Rev. 1971 6 247. 2 3 W. P. Griffith Co-ordination Chem. Rev. 1970 5 459. 24 V. Baram Co-ordination Chem. Rev. 1971 6 65. 2 5 B. Bock K. Flatau H. Junge M. Kuhr and H. Musso Angew. Chem. Internat. Edn., 1971 10 225. 26 R. H. Holm and M. J. O’Connor Progr. Inorg. Chem. 1971 14 241. 2 7 V. Vitzthum and E. Lindner Angew. Chem. Infernal. Edn. 1971 10 315; E. Linder, I-P Lorenz and G . Vitzthum ibid. page 193. 2 8 Y . Marcus E. Hoffman and A. S. Kertes J . Inorg. Nuclear Chem. 1971 33 863

ISSN:0069-3022    

DOI:10.1039/GR9716800251

出版商:RSC    

年代:1971

数据来源: RSC

摘要:

13 The Typical Elements By D. W. A. SHARP M. G. H. WALLBRIDGE Department of Chemistry The University Sheffield S3 7HF and J. H. HOLLOWAY Department of Chemistry University of L eicester L eicester Department of Chemistry University of Glasgow Glasgow G I 2 800 PART I Groups 1-111 1 Group1 The potassium-rubidium and potassium-caesium systems have been studied by thermal methods and there is evidence for a phase KRb in the former case;" the sodium-barium system has been studied in detail from breaks in the resisti-vity-temperature curves. Lithium tetramethylborate has a most unusual and important structure. It is associated in some solvents and is a polymer (1) in the solid. Lithium and boron atoms are joined by strongly co-ordinated linearly bridging single methyl groups (the carbon having trigonal-bipyramidal co-ordination) or by two bridging methyl groups.Polylithiation of many organic ' (a) J. R. Goates J . B. Ott and E. Delawarde Trans. Furaday SOC. 1971 67 1612; ( 6 ) C. C. Addison G. K. Creffield P. Hubberstey and R. J. Pulham J . Chem. SOC. ( A ) , 1971,2688. D. Groves W. Rhine and G. D. Stucky J . Amer. Chem. SOC. 1971 93 1553 254 D . W. A . Sharp M . G . H. Wallbridge and J . H . Holloway species occurs readily and derivatives such as C5Li4 have been obtained from penta-1,3-diyne and n-butyl-lithium in the presence of NNN'N'-tetramethyl-ethylenediamine.," Among the molecules which undergo polylithiation are polynuclear aromatic^,^' nit rile^,^^ and l-phenylpr~pyne.~~ These polylithiated derivatives will undoubtedly be of synthetic use.The characteristic species present in organolithium compounds under various conditions4" have been reviewed. 7Li N.m.r. studies of solutions of phenyl- and p-tolyl-lithium in ether suggest the presence of monomeric species rather than the dimers that have previously been p~stulated.~' The reactions between liquid sodium and acetylenes are more complex than might be supposed. Propyne reacts to give NaC-CMe and MeCH=CH but acetylene gives at first only Na,C and H plus C2H4; in the second stage sodium reacts with hydrogen4 The polymerization of acetylene is catalysed by NaHC .46 The properties of alkali-metal and magnesium derivatives of organo-Si -Ge -Sn -Pb -P -As -Sb and -Bi compounds have been re~iewed.~" Thermal degradation of alkali-metal silicides and germanides gives two series of phases M,E4 and M,E136 (M = Na K Rb or Cs ; x = 3-1 1 ; E = Si or Ge) which are formulated as clathrate-like compounds with the alkali-metal atoms in holes in the three-dimensional lattice of silicon or germanium atoms.'' Other new related ternary phases LiCaE, LiCa,E,, and Lil.,,Ca,.65Si4 have been described." A new ternary silicon nitride, LiSi,N, has been prepared" and might be expected to have a similar type of structure.Rapid freezing of alkali-metal-ammonia solutions containing added salts gives stabilized blue solids which have been studied by e.s.r. spectroscopy.6" Caesium is the only alkali metal to react directly with n-butylamine; the n-butylamides of sodium and potassium6b and potassium methylamide,' are prepared by reaction between the amine and the metal hydride.LiN(SiMe,) shows a monomer-dimer equilibrium in tetrahydrofuran and a dimer-tetramer system in hydrocarbons.6d The ternary nitride chlorides Li ,N3C12 and Li,N2Cl have been formed from the binary salts at high temperatures. Li,N,Cl has an anti-fluorite structure with vacancies in some metal sites.6e The 3 1 complex formed between p,p'-diaminodiphenylmethane and sodium chloride has each sodium atom octahedrally co-ordinated by nitrogen atoms and each nitrogen bonded to (a) R. West and T. Ling Chwang Chem. Comm. 1971 813; (b) A. F. Halasa J . Organometallic Chem. 1971 31 369; (c) G. A. Gornowicz and R. West J . Amer. Chem. SOC. 1971,93 1714; ( d ) R. West and G . A. Gornowicz ibid. p. 1720. ( a ) T .L. Brown Pure Appl. Chem. 1970,23,447; (b) J. A. Laddand J . Parker J . Organo-metallic Chem. 1971 28 I ; (c) C. C. Addison M. R. Hobdell and R. J. Pulham, J . Chem. SOC. ( A ) 1971 1704; ( d ) ibid. p. 1700; ( e ) D . D. Davis and C. E. Gray, Organometallic Chem. Rev. 1970 A6 283. (a) C. Cros M. Pouchard and P. Hagenmuller Bull. SOC. chim. France 1971 379; (b) W. Muller H. Schafer and A. Weiss Z . Naturforsch 1970 25b 1371; 1971 26b, 5 534; (c) E. D. Whitney and R. F. Giesejun. Znorg. Chem. 1971 10 1090. (a) R. Catterall W. T. Cronenwatt R. J. Egland and M. C. R. Symons J . Chern. SOC. ( A ) 1971 2396; (6) W. R. Heumann and L. Safaiik Canad. J . Chem. 1971,49, 1895; ( c ) R. C. Makhija and R. A. Stairs ibid. p. 807; ( d ) B. Y . Kimura and T. L. Brown J .Organometallic Chem. 1971 26 57; ( e ) H. Sattlegger and H. Hahn Z . anorg. Chem. 1970,379,293 The Typical Elements 255 one sodium and through hydrogen to one ~hloride.~" The larger co-ordination number expected for the larger alkali-metal ion is not found in the potassium and rubidium salts of 5-bromo-6-hydroxy-6-methyluracil although the structures may be determined ultimately by hydrogen-bonding rather than by co-ordina-t i ~ n . ~ ' The structures of three cryptates (2) :NaI (2) KI and (2) CsSCN,H,O with the heterocyclic ligand (2) have been determined in each case the metal ion (2) is completely enclosed within the molecular cage of the polyether co-ordination being from all six oxygen and two nitrogen atoms ; the co-ordination polyhedron is intermediate between a bicapped trigonal prism and a bicapped trigonal anti-prism.7c Other major developments in cryptate chemistry have included the measurement of stability constants and other physical properties of complexes formed with alkali-metal and other metal salts.7d Lithium alkoxides are normally polymeric but the degree of association of aryloxides in solution is reduced by sterically active ortho-substituents.8a Dilithium perfluoropinacolate Li,[(CF,),-CO] can be prepared from lithium and perfluoroacetone in tetrahydrofuran.It reacts with labile dihalides e.g. PhPCl, to give 1,3-dioxolans e.g. PhP[OC(CF,),] ." The semidone anions (3) favour a trans conformation in R R \ / c=c / \ '0 0-solutions of the rubidium and caesium salts but a cis conformation in the presence of the smaller alkali-metal cations.The cis-trans ratio in the anions is markedly solvent dependent and is clearly influenced by co-ordination to the cation." Anionic alkali-metal complexes of the type [M(CF,COCHCOCF,),] - (M = Li and Na) have been prepared using A(CF,COCHCOCF,) [A = K+ or ' (a) J. A . J. Jarvis and P. G. Owston Chem. Comm. 1971 1403; (b) M. R. Truter and B. L. Vickery J . Chem. SOC. ( A ) 1971 2077; ( c ) B. Metz D. Moras and R. Weiss, Chem. Comm. 1971 444; ( d ) J. M. Lehn and J . P. Sauvage ibid. 1971 440; A. M. Grotens J. Smid and E. de Boer ibid. p. 759; H. K. Frensdorff J . Amer. Chem. SOC., 1971 93 600 4684; E. M. Arnett and T. C. Moriarty ibid. p. 4908; R. M. Izatt, D. P. Nelson J. H. Rytting B. L. Haymore and J. J. Christensen ibid.p. 1619. (a) K. Shobatake.and K. Nakamoto Znorg. Chim. Acta 1970,4,485; (b) A. P. Conroy and R. D . Dresdner Znorg. Chem. 1970,9,2739; ( c ) G . A. Russell J. L. Geriock and D. F. Lawson J . Amer. Chem. SOC. 1971 93 4088; ( d ) D . E. Fenton and C. Nave, Chem. Comm. 1971,662; (e) J. Emsley J . Chem. SOC. ( A ) 1971,2511,2702 256 D. W . A . Sharp M . G . H . Wallbridge and J. H. Holloway mono-protonated 1,8-bis(dimethylamino)naphthalene] and the metal acetyl-acetonate.8d Alkali-metal fluorides are very soluble in glacial acetic acid ; anion solvation provides the driving force for the solution process.8e 2 Group I1 Beryllium.-In the solid state beryllium borohydride is polymeric with three borohydride groups each chelated through two hydrogen atoms to a central beryllium atom.g Dialkylberylliums R,Be (R = Pr" Bui neopentyl and trimethylsilylmethyl) may be prepared by exchange between diethylberyllium and the appropriate organoborane ; an insoluble hydride Et,Be,H is formed with tri-s-butylborane."" There have been several related studies of adducts of dialkylberylliums and bases.In [MeBeCrCMe,NMe,] two propynyl groups act as bridges to form a central Be,C ring; these are the first bridging acetylenic atoms to be completely characterized.'" The complex Me2Be,2quinuclidine has a monomeric distorted tetrahedral structure. lo' Acetylenic bridges are probably present in adducts of bis(pheny1ethynyl)beryllium' Od and bisalkynyl-berylliums loe although some complexes e.g. (PhC-C),Be,NEt and (MeCrC),-Be,NEt are monomeric.Bis(phenylethyny1)beryllium complexes react with alcohols and thiols to give products of the types PhC-CBeOPh,THF and (PhC=C),Be,(OBu') .lad Bis(neopenty1)beryllium forms complexes with amines and with ethers."/ Organoberyllium compounds have been reviewed. ' Og Alkali-metal amidoberyllates MBe(NH,) (M = Na K Rb or Cs) are formed by allowing beryllium to react with a solution of the appropriate alkali metal in liquid ammonia. ' '" Although many adducts of dialkylberylliums are polymeric, [(Me,Si),N],Be is a monomer. The amino-groups appear to be fairly rigidly held in a staggered conformation and the nitrogen atoms are postulated to form pn-pn bonds to beryllium and pn-dn bonds to silicon.'" A useful review has been published on beryllium salts of carboxylic acids.' Magnesium Calcium Strontium Barium and Radium.-Spectral studies on calcium vapour definitely establish the presence of the Ca molecule in a 'Xg+ ground state.' Sodium and potassium hydrides give good yields of magnesium hydride when they react with magnesium halides in ethers.'," The reaction of excess of aluminium hydride with diethylmagnesium gives magnesium hydride, but at lower ratios of aluminium hydride species such as EtMgAlEt and HMgAlEt,H - (n = 1 4 ) are found.'*' Aminomagnesium hydrides, D.S. Marynick and W. N. Lipscomb J . Amer. Chem. SOC. 1971,93 2322. l o ( a ) G . E. Coates and B. R. Francis J . Chem. SOC. ( A ) 1971 1308; ( 6 ) B. Morosin and J. Howatson J . Organometallic Chem. 1971 29 7 ; ( c ) C. D. Whitt and J. L. Atwood, ibid.1971 32 17; ( d ) G . E. Coates and B. R. Francis J . Chem. SOC. ( A ) 1971 160; ( e ) ibid. p. 474; cf) ibid. p. 1305; ( g ) G . E. Coates and G. L. Morgan Adv. Organo-metallic Chem. 1970 9 195. ( a ) J. Rouxel and L. Brisseau Bull. SOC. chim. France 1971,2000; (b) A. H. Clark and A. Haaland Acta Chem. Scand. 1970 24 3024. l 2 F. Berth and G. Thomas Bull. SOC. chim. France 1971 3467. l 3 W. J. Balfour and R. F. Whitlock Chem. Comm. 1971 1231. l 4 ( a ) E. C . Ashby and R. D. Schwartz Inorg. Chem. 1971 10 355; (b) S. C. Srivastava and E. C. Ashby ibid. p. 186; ( c ) R. G . Beach and E. C. Ashby ibid. p. 906 The Typical Elements 257 HMgNR' (R' = Et Pri Bun or Ph) have been synthesized by hydrogenation and LiAlH reduction of-R2MgNR' compounds and by KH reduction of aminomagnesium bromides.The corresponding alkoxides HMgOR' are unstable and disproportionate to MgH and Mg(0R ') . 14' Biscyclopenta-dienylmagnesium may be prepared under very mild conditions from cyclo-pentadiene and magnesium using cyclopentadienyltitanium trichloride as ~ata1yst.l~" Sparteine is a very good ligand for magnesium in organomagnesium and other magnesium compounds and markedly affects the exchange processes in organomagnesium derivatives ; various conformers are present in solutions of the c~mplexes.'~~ Extensive studies continue to be made on the Schlenk equilibrium (R,Mg + MgX 2RMgX) and the position of equilibrium is dependent upon solvent R and X. Alkyl exchange occurs through a bridging alkyl group.' 5 c In contrast to the predominantly monomeric alkylmagnesium chlorides bromides and iodides alkylmagnesium fluorides are dimeric and there is no Schlenk equilibrium as in the other halides because of the presence of very stable MgFMg bridges.'5d Bridging from chloride must also be considered in equilibria involving these species as is shown by the structure of [EtMg,Cl,,-THF] which is isolated from the reaction between ethyl chloride and magnesium in tetrahydrofuran and which has a cage of magnesium and chlorine atoms.'" Organometallic derivatives of calcium strontium and barium are much less stable than those of magnesium and have hitherto only been described in solution.Phenylethynyl derivatives e.g. Ca(C=CPh) have now been isolated from the reaction between the metal and an acetylene in liquid ammonia as thermally stable solids.16 Barium hydrazide is easy to prepare from hydrazine and easy to handle; on hydrolysis it yields hydrazine.' '" The partial solvolysis of the alkaline-earth pernitrides M3N4 gives alkaline-earth-nitrogen complexes which appear to contain bonded N group^."^ Fusion of germanium nitride with barium oxide gives Ba,Ge,N, which on heating in air is converted into BaGe03.17' The magnesium atom in bispyridinemagnesium phthalocyanine hydrate is significantly out of the plane of the nitrogen atoms of the phthalocyanine system (which is itself non-planar) and is further co-ordinated to the water molecule. 18a Alkaline-earth perchlorates form quite stable hydrazine adducts M(C10,) ,2N,H4 ( a ) T. Saito Chem. Comm. 1971 1422; ( b ) G.Fraenkel C. E. Cottrell J. Ray and J . Russell ibid. p. 273; ( c ) D . F. Evans and G. V. Fazakerley J . Chern. Soc. ( A ) 1971, 184; G . E. Parris and E. C. Ashby J . Amer. Chem. Soc. 1971,93 1206; G. Fraenkel, C. E. Cottrell and D . T. Dix ibid. p. 1704; ( d ) E. C. Ashby and S. Yu J . Organo-metallic Chem. 1971 29 339; ( e ) J. Toney and G. D. Stucky ibid. 1971 28 5 . '' M. A. Coles and F. A. Hart J . Organometallic Chem. 1971 32 279. l 7 ( a ) K.-H. Linke R. Taubert K. Bister W. Bornatsch and B. J. Liem Z . NaturJorsch., 1971,26b 296; K.-H. Linke and K. Schrodter ibid. p. 736; K.-H. Linke K. Schrodter, and M. Krebs ibid. p. 737; ( 6 ) K.-H. Linke and R. Taubert Z . anorg. Chem. 1971, 383 74; ( c ) A. Arbus M.-T. Fournier J . Fournier and M. Capestan Compt. rend., 1971,273 C 751.l 8 ( a ) M. S. Fischer D. H. Templeton A. Zalkin and M. Calvin J . Amer. Chem. Soc., 1971,93,2622; ( b ) V. Y . Rosolovskii and Z. G. Sakk Russ. J . Inorg. Chem. 1970 15, 1369; ( c ) V. I . Esafov and D . S. Shlyapnikov J . Gen. Chem. U.S.S.R. 1970,40 2259; ( d ) B. Metz D. Moras and R. Weiss J . Amer. Chem. Soc. 1971 93 1806 258 D . W . A . Sharp M . G . H. Wallbridge and J . H. Holloway (M = Mg Ca Sr or Ba).'*' The simple bis(pyridine)- and bis(quino1ine)-magnesium iodides decompose on heating with loss of approximately half their pyridine or quinoline as such but the remainder of the heterocycle is cleaved to ammonia and other products in a surprisingly complex reaction.'8c The structures of two cryptate derivatives of barium salts have been elucidated.In [(2)Ba(SCN) ,H,O] the barium is co-ordinated by the eight heteroatoms of (2), in a bicapped trigonal prism ; a water molecule and the nitrogen of a thiocyanato-group are co-ordinated to two faces of the prism. In [(4)Ba(SCN),,2H20] the barium is co-ordinated by the nine heteroatoms of the heterocycle (4) and two (4) water molecules. The extra co-ordination over the co-ordinating atoms of the heterocycle is noteworthy. 18d Pyridinyl radicals complexed to magnesium are formed by the reaction : (py = Me0,C p y - ). It is suggested that the ester groupings are co-ordinated to magnesium. Calcium zinc and manganese complexes have also been prepared ; the complexes are extremely reactive. 9a CaCl ,2MeOH contains octahedrally co-ordinated calcium atoms with bridging chlorines.19' Under hydrothermal conditions the compounds SrHPO, Sr,P,O, Sr,(PO,) , and Sr,(PO,),OH are stable in the strontium orthophosphate system. These are strontium compounds which may possibly undergo incorporation in bone tissue.20u Flux melting of Ca,SiO in CaCl ,2H,O gives Ca,(SiO,)Cl which has an NaC1-type structure.20b The structure of SrBr has now been determined accurately and is a hybrid of the SrC1 structure (CaF type) and the SrI structure (irregular seven-co-ordination about the metal). In SrBr the strontium atoms are seven- and eight-co-ordinate and the bromine atoms have tetrahedral and trigonal co-ordination. la The Raman spectra of magnesium halide-potassium l 9 (a) E. M. Kosower and J. Hajdu J . Amer. Chem. SOC. 1971 93 2534; (b) H.Gillier-' O ( a ) E. Schnell W. Kiesewetter Y . H. Kim and E. Hayek Munatsh. 1971 102 1327; z1 (a) J. G. Smeggil and H. A. Eick Znarg. Chem. 1971 10 1458; (b) V. A. Maroni, Pandraud and M. Philoche-Levisalles Compt. rend. 1971 273 C 943. (b) Von R. Czaya and G. Bissert Acra Cryst. 1971 B27 747. E. J. Hathaway and E. J. Cairns J . Phys. Chem. 1971 75 155 The Typical Elements 259 halide melts show residual lattices [MgX2lp together with a complex anion MgXn2-" (X = C1 or Br). The Mg1,-KI system appears to contain tetrahedral MgI,,- species. l b 3 Group111 Although fewer reviews on this Group have appeared this year two books have been published ; one is an exhaustive survey of the hydrides of the elements within Groups I-IV,22" while the other is an admirable student edition dealing with electron-deficient compounds.22b Both of these texts contain extensive coverage of the Group I11 elements.Specific reviews have dealt with the polypyrazolyl-borate ligand~,~," and the complex metal hydrides again primarily those associated with the Group I11 elements.,,' Two general papers have discussed electron-impact studies on the Group I11 metal alkyls including the measurement of some appearance potential^^^" and the shapes of single polyatomic molecules of the type AH, AH, and AH in terms of a simple qualitative MO approach.24b Boron.-As in 1970 much of the published work has been concerned with the boron hydrides and their derivatives and the carbaboranes and to a lesser extent with boron-halogen and boronxarbon compounds.Several significant developments have occurred in the isolation of heterocycles containing boron, including the isolation of the borabenzene anion C,H,BPh-,25 which had only previously been observed complexed to a transition metal. A useful observation of the structural significance of the number of skeletal bonding electron pairs in carbaboranes higher boranes borane anions and various transition-metal carbonyl compounds has been made which allows the arrangement of the skeletal atoms to be predicted.26" Another general discussion deals with correlations between 13C and "B n.m.r. chemical shifts in a series of tetra-co-ordinate carbon and boron compounds.26b Boron Hydrides. This section deals with the boranes their derivatives and neutral complexes.The borane anions are discussed in a separate section below. A modified topological approach to the valence structures of the boron hydrides has been suggested,'" for use where the open-type B-B-B bonds are excluded because various calculations have failed to provide strong evidence 2 2 ( a ) E. Wiberg and E. Amberger 'Hydrides of the Elements of the Main Groups I-IV' Elsevier Amsterdam 1970 ; (b) K. Wade 'Electron Deficient Compounds', Nelson London 1971. 2 3 ( a ) S. Trofimenko Accounts Chem. Res. 1971,4 17; (6) B. D. James J . Chem. Educ., 1971 48 176. 2 4 ( a ) F. Glocking and R. G . Strafford J . Chem. SOC. ( A ) 1971 1761 ; ( 6 ) B. M. Gimarc, J . Amer. Chem. SOC. 1971 93 593. 2 5 A. J. Ashe and P. Shu J . Amer. Chem. SOC. 1971,93 1804. 2 6 ( a ) K.Wade Chem. Comm. 1971 792; (b) B. F. Spielvogel and J. M. Purser J . Amer. Chem. SOC. 1971,93,4418. 27 ( a ) I. R. Epstein and W. N. Lipscomb Znorg. Chem. 1971 10 1921; (b) 1. R. Epstein, J. A . Tossell E. Switkes R. M. Stevens and W. N. Lipscomb Znorg. Chem. 1971,10, 171 ; (c) I . R. Epstein and W. N . Lipscomb J . Chem. Phys. 1970 53 4418 260 D . W. A . Sharp M . G . H. Wallbridge and J . H . Holloway for the existence of such bonds.27b This method considerably simplifies the computer program used and shows that the known boranes give rise to more allowed valence structures than do hypothetical topologies. A theoretical calculation of the momentum distributions and Compton profiles for the series B,H, B4H 1 B5H 1 and B6H 10 using localized orbitals indicates that this type of approach is useful in interpreting momentum space distribution^.^^' The results of an investigation of B4H10 B,H, B5H11 and B,Hlo by ion cyclotron resonance spectroscopy supported the idea of B,H + and B,H + series of hydrides.For the former the formation of a (M - 1)- ion is favoured, while for the latter the ( M - BH,)- ion is observed. Several odd-electron positive ions were also detected and these were frequently involved in ion-molecule reactions2'" such as B5H,+ + B5H -+ BloHSf + 3H2. The mono-isotopic mass spectra of several boranes @,& B4H10 B5H11 B6HI0, B7Hll B7HI3 B8H12 BsH18 B9H15 B10H14 and B10H16) have been re-calculated from the polyisotopic spectra.28b Various reactions of borane BH, in a fast-flow reactor coupled to a mass spectrometer have been studied.The addition of diborane and pentaborane(9) produces B,H7 and B6H10 (or &HI,) re~pectively.~~" Absolute rate constants for the reactions with ethylene (which yield ethylb~rane),~,' phosphorus trifluoride and trimethylamine (which form the complexes BH ,PF3 and BH ,NMe,) have been determined and compared with those for boron tri-fl~oride.~,' Borane has been detected in an argon matrix which contains the pyrolysis products of BH ,CO although when the pyrolysis temperature is increased from 700 to 810K some H,B,O3 is produced.30" The molecular vibrational constants for various isotopic forms of BH ,CO have been re-calculated,30b and a simplified preparation of this complex and of BH,,PH,, has been described using diborane and the respective ligand in a reaction catalysed by ethers.30c A complete report of the ab initio SCF-MO calculations on BH ,PH and BH ,PF has appeared.la The 'H n.m.r. and i.r. studies on several phosphine-borane complexes reported earlier have been extended to a series of methyl- and ethyl-phosphine-boranes (e.g. EtPH ,BH,) to show that in these monomeric compounds also no H-D exchange occurs between the BH and BD complexe~.~ lb A comprehensive study of nucleophilic substitution at a tetrahedral boron atom in amine-borane complexes has shown that the mecha-nism is dependent upon both the borane fragment and the displacing group. Thus whereas displacement of amine from BH,,NR (R = Me or Et) and RBH,,NMe (R = Bu" Bu' Bus or 0- or p-C6H4X) by tri-n-butylphosphine is 2 8 ( a ) R.C. Dunbar J . Amer. Chern. Soc. 1971,93,4167; ( h ) E. McLaughlin T. E. Ong, 2 9 (a) S. A. Fridrnann and T. P. Fehlner J . Amer. Chem. Soc. 1971 93 2826; (6) T. P. and R. W. Pozett J . Phys. Chem. 1971 75 3106. Fehlner ibid. p. 6366; ( c ) S. A. Fridrnann and T. P. Fehlner J . Phys. Chem. 1971, 75. 271 1 . 3 0 (a)A. Kaldor and R. F. Porter J . Amer. Chem. Soc. 1971,93 2140; ( b ) V . Devarajan and S. J. Cyvin J . Mol. Structure 1971 9,265; ( c ) E. Mayer Monatsh 1971 102 940. 3 1 ( a ) I. H. Hillier and V. R. Saunders J . Chem. SOC. ( A ) 1971,664; ( b ) J. Davis and J. E. Drake ibid. p. 2094 The Typical Elements 26 1 second-order overall with a probable S,2-B mechanism for a similar reaction with Bu'BH,,NMe, and for amine displacement from R,BH,NMe (R = p-C,H,X ; X = halogen) with Ph,(Et)N a first-order process is observed.In the latter case an S,l-B mechanism appears likely with a rate-determining step being the dissociation of the R,BH,NMe c ~ m p l e x . ~ ~ ' ~ ~ The interaction of diborane with lithium dimethylphosphide yields only the bis-borane derivative, Li[Me,P(BH,),]. This anion is similar to those prepared previously from KPH (or NaNMe,) and may be considered as being derived from the B,H,-ion.,,' The species Na[Me,N(BH,),] is also claimed to be the intermediate in the reaction of diborane with Na[Me,NBH,] which yields p-Me,NB,H .33b The crystal structure of the borane complex with the cyclic phosphite ( 5 ) shows that the ring atoms are in a chair configuration with an axial methoxy-group and two equatorial methyl groups.34 ' ( 5 ) (6) The use of diborane in organic syntheses in particular the hydroboration reaction, continues to be a fruitful area of research and several interesting results have emerged.For example the high-yield production of unsymmetrical ketones from olefins via alkylboranes and the cyanoborate ions R,BCN- can be achieved under mild conditions by the route shown in Scheme l.,' The same ions also facilitate the conversion of trialkylboranes into trialkylcarbinol~.~ 5 b Me,C=CMe + [BH,] + (t-hexyl)BH 's (t-hexyl)BRARB 1 ,I,-" R ~ C O R ~ Reagents i Olefin A ; ii Olefin B ; iii NaCN ; iv (CF,CO),O ; v oxidation. Scheme 1 The unstable bis-borolan (6) has been trapped using oct-1-ene or methanol,36" and the more stable six-membered ring system has also been prepared via 32 ( a ) W.L. Budde and M. F. Hawthorne J. Amer. Chem. Soc. 1971,93 3147; ( 6 ) D. E. Walmsley W. L. Budde and M. F. Hawthorne ibid. p. 3150; (c) F. J . Lalor T. Paxson, and M. F. Hawthorne ibid. p. 3156. 33 (a) L. D. Schwartz and P. C. Keller Znorg. Chem. 1971,10 645; (b) P. C. Keller ibid., p. 1528. 3 4 J . Rodgers D. W. White and J. G . Verkade J. Chem. SOC. ( A ) 1971 77. 3 5 ( a ) A. Pelter M . G . Hutchings and K . Smith Chem. Comm. 1971 1048; (6) ibid., p. 1048. 3 6 ( a ) H. C. Brown and E. Negishi J. Amer. Chem. SOC. 1971 93 6682; ( b ) J . Organo-metallic Chem. 1971 28 C1 ; (c) H. C. Brown and S. K. Gupta J . Amer. Chem. SOC., 1971 93 4062; (6) G. Zweifel G. M. Clark and W. C. Polston J. Amer. Chem. SOC., 1971 93 3395; ( e ) L.M. Braun R. A. Braun H. R. Crissman M. Opperman and R. M. Adams J . Org. Chem. 1971,36 2388; (f) J. Beres A. Dodds A. J. Morabito, and R. M. Adams Znorg. Chem. 1971,10,2072 262 D . W . A . Sharp M . G . H . Wallbridge and J . H . Holloway hydroboration reactions.36b Unsymmetrical trialkylboranes have been prepared, and although alkylboranes RBH may be prepared uia hydroboration a more convenient route using lithium aluminium hydride and alkoxyboranes R2BOR has been devised.36c The subtle directive effects in the monohydroboration of a l k y n e ~ ~ ~ ~ and the advantages of using BH,,Me2S both as a hydroborating reagent36e and as a borane carrier in general,36s have been discussed. The action of diborane on cyclopropanes results in cleavage of the C3 ring at 373 K with the B adding to the least substituted C atom but in contrast to hydroboration this reaction is inhibited by ethereal solvents.Tetraborane( 10) reacts similarly but no cleavage occurs with pentaborane(9) reflecting the higher stability of this b ~ r a n e . ~ Exchange reactions between organomercury compounds and diborane afford a convenient synthetic route to phenols through the same type of organo-borane intermediate as is found in hydroboration schemes.38 ArHgBr + B,H % [HHgBr] + ArBH % ArOH H,O I J HBr + Hg The synthesis of air-stable amineboryl tosylates e.g. (p-MeC,H,SO,)BH ,NMe3 and (p-MeC6H4S03)2BH,NMe, by the action of toluene-p-sulphonic acid on BH ,NMe3 has been achieved.,' The i.r. and Raman spectra of isotopic species of tetraborane(l0) have been recorded and nearly all of the fundamental modes a~signed.~'" Fluorophosphines cleave B4HIo according to the scheme:40b B,H, + 2L + L,B3H + L,BH, L,B3H + 2L -P L,,B,H + L,BH, (where L = Me,NPF or F,PH) The molecular structure of bis(trifluorophosphino)diborane(4) (PF,),B,H has been determined by electron diffraction and is shown in (7).The phosphine groups are trans about the B-B axis with the P2B2 atoms being coplanar and although the positions of the hydrogen atoms were not determined uniquely it appears that they occupy terminal and not bridging position^.^^' 3' B. Rickborn and S. E. Wood J . Amer. Chem. Soc. 1971,93 3940. 3 8 S. W. Breuer M. J. Leatham and F. G. Thorpe Chem. Cornm. 1971 1475. 3 9 G. E. Ryschkewitsch Inorg.Nuclear Chem. Letters 1971 7 99. 40 (a) A. J. Dahl and R. C. Taylor Inorg. Chem. 1971,10,2508 ; (6) E. R . Lory and D. M . Ritter ibid. p. 939; ( c ) E. R. Lory R. F. Porter and S. H. Bauer ibid. p. 1072 The Typical Elements 263 Pentaborane(9) the most readily accessible of the middle boranes continues to attract attention. The first direct "B-"B coupling constant has been deter-mined4'" as 19.4 Hz from the high-resolution "B n.m.r. spectrum of B,H,. When the proton coupling is removed a quartet (basal) and multiplet (apical B atom) are observed. The 13C n.m.r. spectrum of the apical-substituted 1-MeB,H8 has led to a reported 11B-13C coupling constant of 72.6 H z . ~ ' ~ It is known that when pentaborane(9) is produced by pyrolytic reactions some similar but less volatile, compounds are also produced.One of these had previously been identified as a l,l'-(B5H8)2 isomer and now two new isomers of this species 2,2'-(B5H,J2 and l,2'-(B,H8)2 have been ~haracterized.~~ Evidence that substitution at the apical-( 1) position is thermodynamically favoured arises from thermal rearrange-ment reactions of p-(Me,Si)B,H ; at 353 K the 2-Me,SiB5H8 isomer is produced which in turn yields l-Me,SiB,H at higher temperature^.^^" The fact that the original isomer does contain a bridging Me,%-group is in little doubt following an X-ray structure determination of 1-Br-p-(Me,Si)B,H (8).43b The silicon atom O H O B @ Si is situated equidistant from the two boron atoms with a B-Si-B angle of only 42.6'. Apical substitution has also been suggested to occur in the derivative (CF,),PB,H,Ni(CO) prepared by the action of nickel carbonyl on l-{(CF3)2P)-B5H8.44a The condensation of silylamines occurs in the presence of B5H and possibly involves a complex in which the N atom in N(SiH,) and MeN(SiH,), is co-ordinated to the B A detailed account of the action of the hydroborate ion on B,H has also appeared.44' The unstable hydride B5Hll forms a 1 :2 complex with ammonia which is best formulated as [H,B(NH,),]+ [B4H9]-.However the initial product may well be different since the reaction solution had to be aged for at least a week before the product formulated above 4 1 ( a ) J . D. Odom P. D. Ellis and H. C. Walsh J . Amer. Chem. SOC. 1971 93 3529; (b) P. D. Ellis J. D. Odom D. W. Lowman and A. D.Cardin ibid. p. 6704. 42 D. F. Gaines T. V. Iorns and E. N. Clevenger Inorg. Chem. 1971 10 1096. 43 ( a ) D. F. Gaines and T. V. Iorns Znorg. Chem. 1971,10 1094; (b) J. C. Calabrese and L. F. Dahl J. Amer. Chem. SOC. 1971,93 6042. 44 ( a ) A. B. Burg and F. B. Mishra J. Organometallic Chem. 1970 24 C33; (b) W. M. Scantlin and A. D . Norman Chem. Comm. 1971,1246; ( c ) C. G. Savory and M. G . H . Wallbridge Znorg. Chem. 1971 10 419 264 D . W . A . Sharp M . G . H . Wallbridge and J . H. Holloway could be isolated.45" A new synthetic route to both B5H1 and has been found through the addition of diborane(6) to the B4H,- and B5H,- ions, re~pectively.~ 5b The SCF wavefunctions for B6Hlo have been determined and the charges on the boron atoms determined as - 0.02e [B(l)] +0.07e [B(2)] + 0.06e [B(3) B(6)], and +0.04e [B(4) B(5)] the balance of charge being on the hydrogen atoms.The bond between the B(4) and B(5) atoms (the shortest known in the boron hydrides) is especially strongly localized and the best single localized bond picture is that shown in (9) although the authors recognize that their charge distribution applies to a static i.e. unperturbed, In the field of the higher boranes much attention has been centred on metallo-compounds with the B, systems. The structure of the complex ion Zn(B,,-H12)22- determined by X-ray methods consists of a Zn" ion tetrahedrally co-ordinated to two bidentate B,,H1,2- ligands ; the cadmium and mercury compounds are isostr~ctural.~~" The complexes themselves have been prepared from the halogeno-magnesium derivatives of B10H14 namely B,,H,,MgX (X = Br or I).46b The actual reaction schemes are complex due in part to un-certainty concerning the precise nature of the magnesium species.However, crystalline double salts of varying composition e.g. (MgY,),(Mg[Hg(B,,H ,,),]>, (Et,O) (Y = C1 Br or I) are believed to be involved. Similar derivatives Me,TIBl,H, and Me,TlB,,H,2TlMe have been obtained by the direct reaction of TlMe with decaborane(l4). The proposed heavy atom structure of the Me2TlBl,H,,- ion shown in (lo) is formally similar to that found46c for the ZnB,,H, fragment in [Zn(Bl,Hl,),]2-. The phosphine derivatives RPB,,H,, (R = Me or Ph) which are formally isoelectronic with the Me,TIB,,H,,- ion, have been synthesized from the action of the dihalide RPCl on a mixture of 4 5 ( a ) G.Kodama J. E. Dunning and R. W. Parry J . Amer. Chem. Soc. 1971,93 3372; ( b ) H. D. Johnson and S. G. Shore ibid. p. 3798. 46 (a) N. N. Greenwood J. A. McGinnety and J . D. Owen J . Chem. Soc. ( A ) 1971,809; (b) N. N. Greenwood and N. F. Travers ibid. 1971 3257; (c) N. N. Greenwood, N. F. Travers and D. W. Waite Chem. Comm. 1971 1027 The Typical Elements 265 B1oH14 and sodium hydride in ethereal solution. A further insertion reaction of the Mn(C0)3 fragment has also been achieved.47 Specific substitution in decaborane( 14) is often difficult but two new useful reactions have been reported. The 6,9-deuterium-labelled borane B ,H ,D, has been obtained via the bridge (p)-substituted compound p-BloH10D4,480 while the 6-substituted derivatives 6-XBloH13 (X = Me Et SCN or OCOMe) are the products of the action of mercury(I1) compounds on the easily prepared BloHl,(R,S) derivative^.^" The “B n.m.r.spectra of a series of specifically labelled B9H13L compounds have been recorded and assigned.49 A detailed report of the electron distribution in B1oH14 has been given.” Borane Anions and Cations and their Derivatives. Low-temperature i.r. and Raman studies of lithium,’ la sodium and potassium hydroborates (and the fully deuteriated compounds)’ l b have been made and assigned. For NaBD, the crystal symmetry is transformed from face-centred cubic to body-centred tetragonal at 197 K and some splittings of the fundamental modes occur.’ The Raman spectrum of Zr(BH4) has been assigned on the basis of a triple hydrogen-bridge ~tructure,’~~ and the tetrahedral symmetry of the molecule has been confirmed by an electron-diffraction study.’” Hydrolysis of the hydro-borate ion BH,- + 3H,O -+ H,B03 - + 4H, is catalysed by Ni-B and Co-B alloys and the use of D,O has shown that the hydrogen evolved derives almost equally from the BH,- ion and the ~olvent.’~ The use of the cyanohydroborate ion in NaBH,CN as a selective reducing agent in organic chemistry continues to be e~tended.’,~.~ The BH,CN- ion which is isoelectronic with CH3CN has also been incorporated into a Ru” complex as [RU(NH,)~(BH,CN)]+ which on acid hydroly~is’~‘ yields the ion [Ru(NH~)~(HCN)]’+.As reported last year, the interaction of sodium hydroborate and iodine yields the B3H8- ion and a further investigation of this reaction shows that diborane(6) is produced at 353 K.” 4 7 J.L. Little and A. C. Wong J. Amer. Chem. SOC. 1971 93 522. 48 (a) J. A. Slater and A. D. Norman Znorg. Chem. 1971,10 205; (b) B. Stibr J. Plesek, 4 9 B. M. Bodner F. R. Scholer L. J. Todd L. E. Senor and J. C. Carter Znorg. Chem., F. Hanousek and S. Hermanek CON. Czech. Chem. Comm. 1971 36 1794. 1971 10 942. R. Brill H. Dietrich and H. Dierks Acta Cryst. 1971 27B 2003. ” (a) K . B. Harvey and N. R. McQuaker Canad. J. Chem. 1971 49 3282; (6) ibid., p. 3272; (c) A. M. Heyns C. J. H. Schutte and W. Scheuermann J. Mol. Structure, 1971 9 271. ” ( a ) B. E. Smith and B. D. James Znorg. Nuclear Chem. Letters 1971 7 857; ( b ) V. Plato and K. Hedberg Znorg. Chem. 1971 10 590.s 3 K. A. Holbrook and P. J. Twist J. Chem. SOC. ( A ) 1971 890. 5 4 (a) R. F. Borch M. D. Bernstein and H. D. Durst J. Amer. Chem. Soc. 1971 93, 2897; (b) R. 0. Hutchins B. E. Maryanoff and C. A. Milewski Chem. Comm. 1971, 1097; ( c ) P. C. Ford ibid. p. 7. ” K. N. Mochalov G. G. Gil’manshin N. G. Gimyatullin and V. K. Polovnyak Trudy. Kazan. Khim.-Tekhnol. Znst. 1969 No. 40 143 (Chem. Abs. 1971 75 14 489h) 266 D . W . A . Sharp M . G . H. Wallbridge and J . H. Holloway Complexes of the neutral borane species B,H have been studied. An intriguing reaction is that between (R,P),PtCl (R = alkyl or aryl) and CsB,H in aceto-nitrile-triethylamine solution when the complex (R,P),PtB,H is produced. X-Ray photoelectron spectral evidence has been quoteds6 to suggest that this complex is best formulated as a derivative of the B,H,,- ion with the bonding being similar to that for the ally1 ion C,Hs-.The 'H n.m.r. spectrum of the complex (C6HSCH2),(Me)N,B,H has been recorded whilst lowering the temperature from 306 to 128 K and shows that the initial broad signal from the borane protons at 306 K gradually sharpens then broadens again corresponding to decoupling arising from more rapid quadrupole relaxation of the "B nuclei and then a slowing of the proton exchange process respecti~ely.~~" Similar n.m.r. studies on other complexes e.g. L,CuB,H [L = PPh or P(OPh),],57b L,CuBH, TlB,H and Me,NB,H ,57c have also shown that quadrupole-induced spin decoupling and a slowing of the exchange process occurs at low temperatures. In these cases and for the icosahedral carbaboranes considerable simplification of the 'H n.m.r.spectrum is achieved by this technique. A con-venient process for the preparation of the B3Hs- ion which does not involve the use of diborane has been reported.57d Alternative synthetic routes to some higher borane anions have also been developed. The alkali-metal salts of the B,,H,22- ion and the free acid H2B12H12 have been isolated from reaction mixtures of sodium hydro-borate and B10H14,58and the pure B,,HllZ- ion (free from the B,,HlO2-ion) has also been ~btained.~" The voltammetric behaviour and the "B n.m.r. spectrum of the latter ion have been reported.58b A complete assignment of the "B n.m.r. spectrum of the BioH13- ion has been made and is consistent with a 3630 model in solution.58c Crystal structures of the two anions B,,HlS2- and (B,,Hl,N0)3- both with the (Et,NH)+ cation have been determined by X-ray method^.^^"*^ The former consists of two B, units similar to those in B1,HlO2- linked by B-B inter-actions from pairs of adjacent apical and equatorial boron atoms in each B, unit.No B-H-B bonds were found and this isomer is therefore different from those previously known where such bonds do exist. In the latter ion two BlOH units are linked by a NO bridge (1 l) analogous in a formal way to the bridging H atom in the B20H19~- ion. The relatively long NO bond distance (128 pm) suggests the possibility of some delocalization of charge from the NO into the B-N bonds. Relatively few borane cationic species have been reported this year.The 5 6 A. R. Kane and E. L. Muetterties J . Amer. Chem. SOC. 1971 93 1041. 5 7 ( a ) W. J. Dewkett H . Beall and C. H. Bushweller Inorg. Nuclear Chem. Letters, 1971 7 633; ( b ) H. Beall C . H. Bushweller and M. Grace ibid. p. 641; ( c ) C. H . Bushweller H. Beall M. Grace W. J. Dewkett and H. S. Bilofsky J . Amer. Chem. SOC. 1971 93 2145; ( d ) W. J. Dewkett M. Grace and H. Beall J . Inorg. Nuclear Chem. 1971,33 1279. 5 8 ( a ) N. T. Kuznetsov and G. S. Klimchuk Russ. J . Inorg. Chem. 1971 16,645; (6) R. L. Middaugh and R. J. Wiersema Inorg. Chem. 1971 10 423; (c) A. R. Siedle G. M. Bodner and L. J . Todd J . Inorg. Nuclear Chem. 1971 33 3671. 5 9 ( a ) C . H. Schwalbe and W. N. Lipscomb Inorg. Chem. 1971,10 151 ; ( b ) ibid. p. 160 The Typical Elements 267 crystal structure of the optically active cation (12) shows the boron atom to be tetrahedrally co-ordinated.60* Displacement of iodide ion from four-co-ordinate boron in trimethylamine adducts of mono- and di-iodoborane with polyamines yields cations of the type [LBH,NMe,]+ I- similar to those reported pre-viously.60b A similar displacement from Me,N,BI with pyridine yields tripositive cations of the type [ ( P ~ ) ~ B ] ~ + ( I - ) .60c (1 1) Carbaboranes Metallo-carbaboranes and Derivatives.These compounds con-tinue to be a source of many papers especially on the dicarbollide system C,B,H 12- and the icosahedral carbaboranes C,BloHl and several significant advances have been made. In this section the compounds are discussed generally in order of the increasing number of skeletal atoms.It has been demonstrated that the series of closo-carbaboranes form a suitable basis for a discussion of all of the known borane and carbaborane structures.61 This approach provides an alternative to that usually adopted namely that all the borane structures with the exception of B,H, are characterized as icosahedral fragments. This structural 6 o ( a ) G. Allegra E. Benedetti C. Pedone and S. L. Holt Inorg. Chem. 1971 10 667; (b) S. A . Gencher G . L. Smith and H. C. Kelly Cunad. J . Chem. 1971 49 3165; (c) R. D. Bohl and G . L. Galloway J . Inorg. Nuclear Chem. 1971,33 885. R. E. Williams Inorg. Chem. 1971 10 210. 6 268 D . W. A . Sharp M . G . H. Wallbridge and J . H . Holloway approach is complementary to that based upon the number of electrons involved in the framework bonding.26 Although no new small carbaboranes have been identified the properties of several existing species have been investigated.The pyrolysis of 1-MeB,H8, l-EtB,H, 1,2-Me2B,H7 and 1,2-tetramethylenediborane above 773 K affords various carbaboranes containing one two or more carbon atoms. Thus 1,2-Me2B,H7 gives a 26 % yield of 1,5-C2B3H and (CH2),B2H4 affords a lower yield of C4B,H6 at 823 K.62a There is evidence from the "B n.m.r. spectrum at 373 K that the bridge hydrogen in CB,H7 (12a) also obtained in the above study undergoes exchange probably from one face to another although the actual position is not certain.62b Sly1 derivatives Of C2B4H8 have been prepared from the reaction of various silanes with B4H10 B,H, or C2B4H itself at elevated temperature^.^^" The silyl group is here situated on one of the carbon atoms and a possible precursor in this process namely the bridge-substituted silyl derivative of C2B4H (12b) has also been prepared at lower temperatures from the action of Me,SiCl on the sodium salt of the C2B4H7- anion.63b Halogen substitution in C,B4H and its C-methyl derivatives has been shown to occur exclusively at the B(3)-po~ition.~~' The microwave spectrum of 2-chloro-l,6-dicarbahexaborane(6) shows the C2B4 framework atoms to be arranged as a distorted ~ c t a h e d r o n ~ ~ ' and the preparation of the dilithio-derivative LiCB4H4CLi has led to the isolation of the MeCB4H4CMe compound.64b The vibrational spectra (ix.and Raman) of the closo-carbaboranes C2B3H , 1,6-C2B4H, and C2B,H have been reported.65 One of the few investigations on the mechanism of carbaborane formation has been made using the reaction of acetylene (and C,D,) with B4H10.66 This reaction is relatively simple at lower temperatures and yields only methyl 6 2 6 3 6 4 6 5 6 6 ( a ) E.Groszek J. B. Leach G. T. F. Wong C. Ungermann and T. Onak Inorg. Chem., 1971,10,2770; ( b ) T. Onak and J. B. Leach Chem. Comm. 1971,76. ( a ) W. A. Ledoux and R. N. Grimes J . Organometallic Chem. 1971 28 37; (b) C. G . Savory and M. G. H. Wallbridge Chem. Comm. 1971 622; (c) J. S. McAvoy C. G. Savory and M. G. H. Wallbridge J . Chem. SOC. ( A ) 1971 3038. ( a ) G. L. McKown and R. A. Beaudet Inorg. Chem. 1971 10 1350; ( b ) R. R. Olsen and R.N. Grimes ibid. p. 1103. R. W. Jotham and D. J. Reynolds J . Chem. SOC. ( A ) 1971 3181. D. A. Franz and R. N. Grimes J . Amer. Chem. SOC. 1971,93 382 The Typical Elements 269 derivatives of C,B,H in addition to a white solid polymer. From the kinetic study a possible reaction scheme was proposed to include : B4H10 B4H8 + H2 /B3c2H7 + [BH31 B4H8 + C2H2 * B4C2H10 B4C4H12 -P 2-MeC,B3H + [BHJ The formal nido-c,B,H,’- and ~yclo-B,C,H,~- anions have been incorporated into metallo-carbaboranes e.g. (1 3) from the reaction of iron pentacarbonyl with nido-C,B,H The structure of the nido-CB,H molecule has been shown by microwave spectroscopy to consist of a pentagonal-pyramidal framework, with terminal and bridging hydrogen atoms.67b 2 1 0 0 In the middle range of carbaboranes three derivatives of new nido-carbaborane families have been identified as C,B,H ,68a C,Me,B,H (14) and C,Me,-B8H10,68b whichareisoelectronicwithC,B,H ,B9HI3 ,and BloHl,,respectively.The C3B,H is the first reported carbaborane to contain a ‘bare’ carbon atom, b 7 (a) R. N. Grimes J . Amer. Chem. Soc. 1971 93 261; (6) C. S. Cheung and R. A. Beaudet Inorg. Chem. 1971 10 1144. 6 8 (a) M. L. Thompson and R . N. Grimes J . Amer. Chem. Soc. 1971,93,6677; ( b ) R . R. Rietz and R. Schaeffer ibid. p. 1263; (c) P. M. Garrett G. S. Ditta and M. F. Hawthorne ibid. p. 1265 270 D . W. A . Sharp M . G . H. Wallbridge and J . H . Holloway and while dodecahedra1 (near D2,,) symmetry is suggested for the solid some cage rearrangement possibly occurs in solution.Another study has reported a different isomer of the C2B8H12 molecule.68' The novel mixed carbaborane complexes such as [B-CO.B'-CO.B'CO.B]~- (where B = C2B,Hll and B' = C2B8H10), whose structure was reported last year have been further des~ribed,~," and another 1 1-atom metallo-carbaborane (n-C5H,)Co(C2B8 Hlo) has been prepared, by a polyhedral expansion reaction from dOS0-1,6-C2B8H Two crystal structures of metal-dicarbollide complexes [CsCr(C,B,-H,Me2)2],H,070" and Co"' [C2B,Hlo)2S2CH]70b have shown that in common with other similar complexes the metal atom completes an icosahedral type of framework. In both compounds the transition-metal atom is sandwiched between two mutually staggered C2B9 frameworks and is linked symmetrically to the five atoms (3B and 2C) in the open face.In the former the methyl groups are bonded to the carbon atoms and in the latter the two ligands are linked by an -S-CH-S- bridge. The preparation of this latter complex together with the corresponding Fell1 compound has been described.70c .69b + C O ( C ~ B H ~ ~ ) ~ - + CS2 + H+ + (C~B~H~O)~(S~CH)CO + Hz Reduction of this bridged species yields the anion [(C2B,H o)2(S2CH2)Co] -, which presumably contains an -S-CH2-S- bridge. The two C2B,Hl, ligands have also been linked by the -0-C(CH3)-0- group. The possibility that the dicarbollide ligand will undergo rearrangement reactions at higher temperatures similar to those observed for the parent carbaborane 1,2-C2BlOHl2 has been realized in the complex (n-C,H,)Co(C2B,Hl in that above 673 K one (or both) of the carbon atoms in the open B3C2 face are displaced from the face to yield different isomers.71 Mossbauer spectra72" and polaro-graphic and cyclic voltammetric have been made on a series of transition-metal-dicarbollide complexes and the latter measurements have indicated that it is possible for the metal to exist in a series of low oxidation states in such compounds.The Fe" complex [Fe(C2B,Hll)]22- may be protonated in strong acid to form a possible analogue of protonated ferrocene which reacts further with dialkyl sulphides to yield boron-substituted dicarbollide l i g a n d ~ . ~ ~ ' + [Fe(C2B,H,,)2]2- -% [HFe(C2B,H '& R2SH+ + [Fe(C2B,Hl,)z]2-1 H2 + [Fe(CzB,Hl I ) ( C ~ B ~ H ~ O S R ~ ) I Spectroscopic studies on [(3)-1,2-C2B,H12]- [(3)-1,7-C2B,H12]- and (3)-1,2-6 9 (a) J .N. Francis and M. F. Hawthorne Inorg. Chem. 1971 10 863; ( 6 ) W. J. Evans and M. F. Hawthorne J . Amer. Chem. Soc. 1971,93,3063. ' O (a) D. St. Clair A. Zalkin and D. H. Templeton Inorg. Chem. 1971 10 2587; (b) M. R . Churchill and K. Gold ibid. p. 1928; (c) J. N. Francis and M. F. Hawthorne, ibid. p. 594. 7 1 M . K. Kaloustian R. J. Wiersema and M. F. Hawthorne J . Amer. Chern. Soc. 1971, 93 4912. 72 ( a ) T. Birchall and I. Drummond Inorg. Chem. 1971 10 399; (b) W. E. Geiger and D. E. Smith Chem. Comm. 1971 8 ; ( c ) M. F. Hawthorne L. F. Warren K. P. Callahan and N. F. Travers J . Amer. Chem. Soc. 1971 93 2407 The Typical Elements 27 1 C2B,H13 have led to assignment of the "B n.m.r. spectra 73u and have suggested that in the first ion the extra hydrogen atom is exchanging in B-H-B bonds at the open face while in the second it is in a static B-H-B bond.73b When nido-(3)-1,2-C2B,H 13 is treated with beryllium,74" aluminium or gallium74b alkyls two types of compound are obtained a closo-C2B,H,,MR (R = Et,O when M = Be) and a nido-C,B,H,,MR (M = A1 or Ga).The crystal structure of the aluminium compound C,B,H,,AlMe (15) shows a very small B-Al-B angle suggesting that the Me,A1 group may be bonded to the two boron atoms by bridging hydrogen atoms.74c An interesting series of easily accessible carbaboranes containing only one carbon atom nido-C(NH3)B,,H, (16) [closo-CB,H,,]- (17) and [closo-CB 1H12]- have been obtained from de~aborane(l4).~'" BloH, + 2NaCN -P Na,B,,H,,CN 3 C(NH,)B,,H,, C(NMe,)B,,H ,(OH) NaoHb C(NMe,)B,H, * [CB,H,,]-C(NH,)B,,H ,-( L C(NMe,)B,,H, 5 [C(H)B,,H,J '* [CBllH,J-(a) A.R. Siedle G. M. Bodner and L. J. Todd J. Organometallic Chem. 1971 33, 137; (6) D. V. Howe C. J. Jones R. J. Wiersema and M. F. Hawthorne Inorg. Cht m., 1971,10,2516. ( a ) G. Popp and M. F. Hawthorne Inorg. Chem. 1971 10 391 ; (6) D. A. T. Young, R. J. Wiersema and M. F. Hawthorne J. Amer. Chem. Sac. 1971,93 5687; (c) M. R. Churchill A. H. Reis D. A. T. Young S. R. Willey and M. F. Hawthorne Chem. Comm. 1971,298. (a) W . H. Knoth Inorg. Chem. 1971 10 598; (b) D. C. Beer A. R. Burke T. R. Engelmann B. N. Storhoff and L. J. Todd Chem. Cornm. 1971 161 1 272 D. W. A . Sharp M . G . H . Wallbridge and J . H . Holloway Several metallo-monocarbaboranes derived from [C(H)Bl OH10]3 - and [C(NH3)BIOH10]2- have also been prepared.75" Acid hydrolysis of the [closo-1,2- [1,7- and [1,12-C(H)EB,oHlo]2- (E = P or As) ions also affords ll-atom fragments [7-CHB ,,H 2]2 - ¶ [7,8-C(H)EB,H - and [ 1-CHBloH12] - respec-t i ~ e l y .~ 5 b Electron-diffraction studies on clos0-1,2- 1,7- and 1,12-C2BloHl in the vapour phase show the C,Bl0 fragment to be a slightly distorted icosahedron similar to that in thesolid-state and molecular motion in the 1,2- and 1,7-isomers has also been determined.76b Another crystal structure determination on C(Ph)C(HgI)(CI)BloHlo suggests that this type of derivative may react by separation of HgI from two adjacent molecules leading to the Bloc2-Hg-C,Blo unit as a reaction intermediate.76c Many of the papers on C,BloHl, refer to various organic derivatives and include -OH,77u -Cl,77b9c -(CH2),N02,77d - NO,,^^= - CH2CH0,77S -BC1 (substitution on C atom),77g and -C02H.77h The C atoms of the framework have been in-corporated into cyclic systems; the benzocarbaborane (18) shows high stabi-lit^^^" but very little aromatic character whereas the alkenyl derivative (19) may be degraded to the analogue of the dicarbollide ion and combined in a similar way with transition metals.78b Several compounds involving a transition-metal-carbon a-bond have been e.g.C2BlOH ,Fe(CO),(n-C,H,) and the ferrocene-type derivative (20) has been obtained from the action of Na(x-C,H,)Fe(CO) on C,(COC1),B1,H1 at 473 K.79c H-H H \ / c-c 4 % c-c C \ 7 -\o/ BlOHlO H H I c-c Q/ BlOHlO 7 6 ( a ) R.K. Bohn and M. D. Bohn Inorg. Chem. 1971 10 350; (b) R. H. Baughman, J . Chem. Phys. 1971,55 3781 ; ( c ) V. I. Pakhomov A. V. Medvedev V. I. Bregadze, and 0. Yu. Okhlobystin J . Organometallic Chem. 1971 29 15. 7 7 ( a ) L. I . Zakharkin V. V. Gedymin and V. N. Kalinin Zhur. obshchei Khim. 1970, 40 2653; ( 6 ) V. I. Stanko G . A. Anorova T. V. Klimova and T. P. Klimova ibid., p. 2432; (c) V. I . Stanko A. I . Klimova P. I . Belik and K. P. Butin ibid. 1971 41, 338; ( d ) A. V. Kazantsev M. M. Aksartov and L. I. Zakharkin ibid. p. 71 1 ; (e) L. I. Zakharkin and G. G. Zhigareva ibid. p. 712; (f) A. V. Kazantsev and L. E. Litovchenko ibid. 1970 40 2768; ( g ) B. M. Mikhailov E. A. Shagova and T.V. Potapova Izvest. Akad. Nauk S.S.S.R. Ser. khim. 1970,10,2048; (h) L. I. Zakharkin, V. N. Kalinin and V. V. Gedynin Synthesis Inorg. Metal-org. Chem. 1971 1 45. 7 8 ( a ) D. S . Matteson and N. K. Hota J . Amer. Chem. Soc. 1971 93 2893; ( b ) D. A. T. Young T. E. Paxson and M. F. Hawthorne Inorg. Chem. 1971 10 786. 7 9 (a) D. A. Owen J. C. Smart P. M. Garrett and M. F. Hawthorne J . Amer. Chem. SOC. 1971,93 1362; ( b ) L. 1. Zakharkin and L. V. Orlova Izvest. Akad. Nuuk S . S . S . R . , Ser. khim. 1970 10 2417; (c) L. I. Zakharkin L. V. Orlova A. I. Kovredov L. A. Fedorov and B. V. Lokshin J . Organometallic Chem. 1971,21,95 The Typical Elements 273 The reduction of 1,2-C,BloHl to [1,2-C2BloH,,]2- followed by reaction with CoCI,-NaC,H, yields (C,H,)Co(7,8-C2BloH12) which possibly contains a 13-atom polyhedral fragment." Further information has been given on the very stable series of anionic chelated transition-metal biscarbaborane complexes containing metal-carbon a-bonds,' l o reported last year and biscarbaborane itself has been degraded by ethanolic KOH to form initially the anion [B,,C,H ,-B,C,Hl J- and finally C2B,H -C2B,H which is linked through two carbon atoms.' l b Boron-Carbon Compounds.Cyclopentadienyldiethylborane,s20 (o-C,H,)BEt , and other mixed trialkylboranes82b have been prepared by the routes : Et,BCl,L + NaC,H + Et,B(C,H,),L 3 Et,B(C,H,) 3R',BOMe + LiAlH + 3(olefin) + 3R1,BR2 + LiAl(H)(OMe), (L = C,H,N or NMe,) The latter synthesis may be modified to allow the easy preparation of dialkylboron hydrides.Contrary to an earlier report no isomerization of Bun Bus or Bu' occurs in the syntheses of trialkylboranes using Grignard reagents.82c Ethyl-halogenoboranes are obtained conveniently from the action of triethylaluminium on the boron halides BX (X = C1 Br or I).82d The photoelectron spectrum of trivinylborane in comparison with that of triethylborane suggests that only little conjugation exists between the vacant p orbital on the boron atom and the vinyl Studies on the processes occurring in the oxidation of trialkylboranes have suggested that at 303 K in solution a homolytic chain reaction is involved and that while initially the direct reaction between R,B and 0 is important the subsequent kinetics are largely determined by the unimolecular decomposition of R,BOOR Other results have also indicated that such a species is involved in an autocatalytic process and that it is primarily the alkyl and alkylperoxyl radicals which are chain carriers.84b Oxidation at 398 K appears to be somewhat different and mass spectrometric evidence indicates intermediates of the type Me,B,O .84c Steric crowding around the boron is also an important The unimolecular decomposition of BuiB between 407 and 469 K in the presence of ethylene yields 2-methylpropene and triethylborane and the kinetic results are consistent with a H o G.B. Dunks M. M. McKown and M. F. Hawthorne J . Amer. Chem. Soc. 1971 93, 2541. ( a ) D. A. Owen and M . F. Hawthorne J . Amer. Chem. Soc. 1971 93 873; (6) M. F. Hawthorne D. A. Owen and J . W. Wiggins Inorg.Chem. 1971 10 1304. 8 2 (a) H. Grundke and P. I. Paetzold Chem. Ber. 1971 104 1136; (b) H. C . Brown and S. K. Gupta J . Amer. Chem. SOC. 1971 93 1818; (c) A. G. Davies B. P. Roberts, and R. Tudor J . Organometallic Chem. 1971 31 137; ( d ) H . Noth and W. Storch, Synthesis Inorg. Metal-org. Chem. 1971 1 197. L ( 3 A. K. Holliday W. Reade R. A. W. Johnstone and A. F. Neville Chem. Comm., 1971 51. H 4 ( a ) A. G. Davies K. U. Ingold B. P. Roberts and R. Tudor J . Chem. SOC. (B) 1971, 698; (6) J. Grotewold J. Hernandez and E. A . Lissi ibid. p . 182; ( c ) L. Barton and G. T. Bohn Chem. Comm. 1971 7 7 ; ( d ) H . C . Brown and M . M. Midland ibid., p. 699 274 D . W . A . Sharp M . G . H. Wallbridge and J . H . Holloway polar four-centre transition state.8 In addition to this general elimination of an alkene in the presence of another it has been found that other groups e.g.2-methyl-2-nitrosopropane and cis-(but not trans-)azobenzene will achieve a similar r e ~ u l t ~ ~ ~ ~ ~ as shown in Scheme 2. HNBu' / -t rBU' 0 ; N/Ph II Ph N\ I 0 \ / C Scheme 2 Several interesting studies of homolytic substitution at the boron atom in BR, compounds have been made. In the reaction of methyl radicals with triethyl-borane in the gas phase two important reactions are substitution and hydrogen abstraction.86" Me' + Et,B * MeBEt + Et' Me' + Et,B -+ MeH + Et,B(C,Hd) Other results obtained for the liquid phase on a series of trialkylboranes and trialkylboroxines have shown that t-butoxyl and t-butylthiyl radicals also induce a bimolecular homolytic substitution reaction at the metal centre yielding for example R,BSBu".The radicals eliminated in these cases have been detected by e.s.r. A neat extension to this work has shown that since reactions of alkoxyl radicals and the triplet state (n+ n*) of ketones are similar under irradiation ketones also cause displacement of alkyl radicals from trialkylboranes.86dye R',CO* + R2,B 3 R1,kOBRZ2+'R2 The action of iodine on triethylborane which yields Et,BI is believed to occur through a free-radical me~hanism,~ 7a while a similar reaction between bromine and tri-exo-norbornylborane results in inversion of configuration at carbon to give predominantly endo-brom~norbornane.~ 76 A method for the synthesis of 8 5 (a) A. T. Cocks and K.W. Egger J . Chem. SOC. ( A ) 1971 3606; (6) A. G . Davies, K. G. Foot B. P. Roberts and J. C. Scaiano J . Organometallic Chem. 1971 31 C1; (c) K. G. Foot and B. P. Roberts J . Chem. SOC. (C) 1971 3475. 8 6 (a) J . Grotewold E. A. Lissi and J. C. Scaiano J . Chem. SOC. (B) 1971 1187; (b) A. G. Davies D. Griller and B. P. Roberts ibid. p. 1823 ; (c) A. G. Davies and B. P. Roberts, ibid. p. 1830; ( d ) A. G. Davies B. P. Roberts and J. C. Scaiano ibid. p. 2171; ( e ) M. V. Encina and E. A. Lissi J . Organometallic Chem. 1971 29 21. (a) E. A. Lissi and E. Sanhueza J. Organometallic Chem. 1971,26 C59; (b) H. C. Brown and C. F. Lane Chem. Comm. 1971 521 The Typical Elements substituted pentadienes has been devised which uses triallylborane.88" \ /OR1 H3C-C //O H \ /CH, /c=c\ ally1,B + R'OC-CH -+ ally1,B ,CH -!% H,C=C H,C=C \ \ H H 275 Other unsaturated boranes alkoxydivinylboranes have been used to synthesize the borane-transition metal complex (21) by interaction with Fe,(C0),.88b A series of dialkylborane complexes e.g.Me,B-S-R where R = H Me Ph, BMe SnMe Mn(CO) etc. have been synthesized from dimethylborane compounds Me,BX (e.g. X = SH or Br).89 Several studies relate to species containing BR,- anions and their derivatives. The tetraphenylborate ion BPh,- is known to bond through a phenyl ring to rhodium and iridium and a further complex with ruthenium (22) has now been reported."" (x-C,H,)Ru(PPh,),CI + NaBPh -P (n-C,H5)RuBPh, The oxidation of the [BPh,] - ion by hexachloroiridate(1v) ions occurs quanti-tatively in aqueous solution and BPh radicals are believed to be involved.90b A novel rearrangement occurs when hindered tetra-arylborate salts are photolysed in that a shift of one of the aryl groups occurs and a substituted triarylborane is formed."' The [BPh,]- ion also acts as an effective arylating agent with mercury(I1) chloride yielding PhHgCl at 373 K and with chlorinated solvents (e.g.CCl and CHCl,) phenylboron chlorides are formed.g0d Trialkylcyano-borates BR,CN- are effective intermediates in the high-yield conversion of trialkylboranes to trialkylcarbin~ls.~~ 8 8 (a) B. M. Mikhailov Yu. N. Bubnov S. A. Korobeinikova and S. I. Frolov J . Organo-metallic Chem. 1971 27 165; ( 6 ) G. E. Herberich and H. Muller Angew Chem. Internat. Edn.1971 10 937. ( a ) R. J. Haines and A. L. du Preez J . Amer. Chem. SOC. 1971 93 2820; ( b ) P. Abley and J. Halpern Chem. Comm. 1971 1238; (c) P. J. Grisdale J . L. R. Williams M. E. Glogowski and B. E. Babb J . Org. Chem. 1971 36 544; (d) A. A. Koksharova, G. G . Petukhov and S. F. Zhil'tsov Zhur. obshchei Khim. 1970 40 2449. A. Pelter M. G. Hutchings and K. Smith Chem. Cornm. 1971 1048. 8 9 H. Vahrenkamp J . Organometallic Chem. 1971,28 167. 9 216 D . W . A . Sharp M . G . H . Wallbridge and J . H . Holloway A 'H n.m.r. study of the exchange between Me,P,BMe and excess trimethyl-phosphine suggests that the reaction proceeds through a dissociative mechanism similar to that in the system involving trimeth~lamine.~~ Compounds containing B-N Bonds. Those compounds such as the borazines, which contain B-N in a cyclic system are discussed below in the section dealing with heterocycles containing boron.Among those complexes with a four-co-ordinate boron atom the B-N distance in Me,N,BF has been determined as 164 pm from measurements of the microwave spectrum. This value is almost identical with that in Me,N,BH, (165 pm) obtained in the same way but rather larger than the value (158 pm) obtained for Me,N,BF from X-ray data.93a Calculations of stretching force constants for B-N bonds from i.r. and Raman data show that they follow the order expected in the series MeCN,BF < MeCN,BCl - MeCN,BBr,.93b The stability of the B-N bond in a series of complexes Me,N,BX (X = H F, C1 Br or I) and some mixed halides e.g. Me,N,BF,Br has been related to the fragmentation pattern in the mass spectra in that in the complexes where X = H (or F) ions such as Me," and H,C,N+ predominate whereas in the heavier halides [Me,NBX,] + ions are found.93' Various mixed boron halide adducts have been obtained through exchange reactions in mixtures such as Me,N,BBr, with BCl,.94" Other 1 1 complexes reported involve BX (X = Me F or C1) with methylhydrazine derivatives,94b and BX (X = H or F) with methyl esters of amino-acids such as glycine and /I-alanine and in this case borazines e.g.(FBNCH,CH,CO,Me) have been prepared from the BF complexes.94c Hexacyanoiron(I1) acid H,[Fe(CN),] and the isocyanide compounds Fe(CNR),(CN) (R = Me or Et) combine with boron halides to form Fe(CNR),-(CN,BX,) (R = H Me or Et when X = F ; R = Me or Et when X = Cl) and it is interesting that spectroscopic measurements indicate that the groups CNR and CNBX possess similar 7r-bonding ligand properties.94d Among those compounds containing a three-co-ordinate boron atom the photoelectron spectra of thirteen aminoboranes R,NBX2 (R,N),BX and (R,N),B (X = H alkyl F C1 or Br) have been recorded and bands at low energy have been assigned to ionizations from the n-ele~trons.~~" Similar assignments have been made for the spectra of B,(NMe,) and electron-rich olefins such as C,(NMe,) and {C[N(Me)CH,],} .95b The action of vaporized carbon on Me,NBH yields mainly Me,NBHMe (which combines with the original material to yield a dimeric product) together with Me,NBMe and ')' K.J . Alford E. 0. Bishop P.R. Carey and J. D. Smith J . Chem. Soc. ( A ) 1971, 2574. 93 (a) P. S. Bryan and R. L. Kuczkowski fnorg. Chem. 1971 10 200; (6) D. F. Shriver and B. Swanson ibid. p. 1354; (c) G. F. Lanthier and J. M. Miller J . Chem. Soc. ( A ) , 1971 346. 94 (a) S. S. Krishnamurthy and M. F. Lappert fnorg. Nuclear Chem. Letters 1971 7 , 919; (6) L. K. Peterson and G . L. Wilson Cunad. J . Chem. 1971,49 3171 ; (c) E. F. Rothgery and L. F. Hohnstedt fnorg. Chem. 1971 10 181 ; ( d ) D. Hall J. H. Slater, B. W. Fitzsimmons and K. Wade J . Chem. Soc. ( A ) 1971,800. 9 5 (a) H. Bock and W. Foss Chem. Ber. 1971 104 1687; ( 6 ) B. Cetinkaya G. H. King, S. S. Krishnamurthy M. F. Lappert and J . B. Pedley Chem. Comm. 1971 1370 The Typical Elements 277 Me,NH,BH .96a A convenient preparation of aminoboranes has been de-veloped from triphenyl borate."' H, B(OPh) + R2NH + Al p,k * (RlN),-,BH + AI(OPh), (R = Et Pri or C5Hlo; P - 4000 psig; T - 450 K ; n = 1 or 2) Trimethylsilyl derivatives of aminoboranes (Me,Si),NB(Cl)NMe and (Me,Si),NB(NMe,) have been obtained97" from the action of the lithium salt of hexamethyldisilazane on ClB(NMe,) .The rotational barriers about the B-N bonds in such compounds have been to be 75-88 kJ mol- '. Several compounds derived from hydrazine have also been reported e.g. XNH-NH-BPh (X = C6H,C0 CH,CO or Ph,PO) which show some internal co-ordination through B-0 bonds,98" and RiB-NR2-NR2-BRi (R' = alkyl or aryl R2 = alkyl or H) which show some intramolecular hydrogen-bonding.98b The completely substituted compound B(NHNMe,) forms addition products with BCl and B,H, in sharp contrast to B(NMe2) which shows no such donor proper tie^.^^' The crystal structure of Ph,C=NB(mesityl) shows the C-N-B linkage to be almost linear with short B-N (140 pm) and C-N (131 pm) distances, suggesting that this system is an analogue of allene with appreciable n-bonding between the three atoms C=N 2 B.99a An indirect method for measuring the "B-H coupling constants from line-broadening in both 'H and "B n.m.r.spectra has been shown to be applicable to a variety of compounds containing a B-N bond.996 Compounds containing B-0 Bonds. The syntheses of the first perfluoroalkyl-borate esters have been achieved by two general 3R,OCI + BCI -P (R,O),B + 3C1, \ \ / / (R = CF, C3FTi or C,F,'; Rhal = CF or CF2Cl ; X = CI Br I or SMe) B-x + Rha,-cO-Rh, + B-o-c(Rh,,)2-x These esters are unstable at ambient temperatures when R = CF or C3F7i but stable when R = C,F,'.A convenient route to aikylboronic esters has been found via hydroboration reactions (Scheme 3). l o l a y b ( a ) W. Haubold and R. Schaeffer Chem. Ber. 1971 104 513; ( 6 ) R. A. Kovar R. Culbertson and E. C. Ashby Znorg. Chem. 1971 10 900. 9 7 ( a ) H. L. Paige and R. L. Wells Znorg. Chem. 1971 10 1526; (b) R. L. Wells H. L. Paige and C. G. Moreland Inorg. Nuclear Chem. Letters 1971 7 177. ( a ) H. Noth W. Regnet H. Pihl and R. Standfest Chem. Ber. 1971 104 7 2 2 ; (b) H. Noth i&id. p. 558; (c) H. Noth and H. Suchy ibid. p. 549. 99 ( a ) G. J . Bullen and K. Wade Chem. Comm. 1971 1122; (b) V.S. Bogdanov A. V. Kessenikh and V. V. Negrebetsky J . Magn. Resonance 1971,5 145. l o o ( a ) D. E. Young L. R. Anderson and W. B. Fox Znorg. Chem. 1971 10 2810; (b) E. W. Abel N . Giles D . J . Walker and J . N . Wingfield J. Chem. SOC. ( A ) 1971, 1991. l o ' (a) H. C. Brown and S. K . Gupta J . Amer. Chem. Soc. 1971 93 1816; (b) C. Cone, M. J. S. Dewar R. Golden F. Maseles and P. Rona Chem. Comm. 1971 1522 278 D . W . A . Sharp M . G . H . Wallbridge and J . H. Holloway olefin + BH3,C,HsO + Scheme 3 Further evidence concerning rearrangement reactions during fragmentation processes in mass spectrometry arises from the observance of tropylium ions from cyclic (and acyclic) derivatives of phenylboronic acids such as PhB(OEt) . l0lb General principles in the structures of anhydrous crystalline borates have been further developed.'02" In general the boron atoms are divided into two types depending upon whether they have three or four neighbouring oxygen atoms, whereas the oxygen atoms are of three different types namely those which are close to one two or three boron atoms.The crystal structures of several borates have been determined. Zinc diborate ZnB,O contains planar BO and tetra-hedral BO units sharing a common vertex with each zinc atom being surrounded by four oxygen atoms.lo2' In copper metaborate CuB,O, the BO tetrahedra share four common oxygen atoms with each copper atom in a square planar co-ordination,lo2" and in lithium borate a-Li,BO there is an unusual type of framework containing single BO units with the co-ordination around the lithium atoms being a very distorted tetrahedron of four oxygen atoms.'02d The monomeric molecule HBO has been trapped in an argon matrix and identified from its i.r.spectrum as containing a linear skeleton.'03 The heat of complexing of boric acid in alcohol has been determined,lo4" and a brief survey of the inter-actions in the boric acid-mannitol system has been made but the actual composi-tion of the complex remains unknown.'04b Compounds containing B -Halogen Bonds. This section discusses successively the boron trihalides the lower halides and fluoroborate compounds. The high-resolution photoelectron spectra of the boron halides have been recorded and the relative calculated energies of the n-stabilizations follow the sequence BF > BCl > (BBr - BI,) although it is shown that this can be reconciled with the opposite sequence of rc-electron delocalization.Vibrational fine structure was observed in the spectra of BF and BCl, and some of the bands in BBr and BI show splittings arising from spin-orbit coupling.'05" A study of the n.q.r. spectra of more than twenty compounds containing B-C1 bonds has been made and the field-gradient asymmetry parameter at the halogen ( a ) M. L. Huggins Inorg. Chem. 1971 10 791 ; (6) M. M. Ripoll S. M. Carrera and G . Blanco Acta Cryst. 197 I B27 672 ; ( c ) ibid. p. 677 ; ( d ) F. Stewner ibid. p. 904. I " ' E. R. Lory and R. F. Porter J . Amer. Chem. SOC. 1971,93 6301. I o 4 (a) R. F. Nickerson J . Inorg. Nuclear Chem. 1971 33 1665; (b) L.B. Magnusson, ibid. p. 3602. l o ' (a) P. J. Bassett and D. R. Lloyd J . Chem. Soc. ( A ) 1971 1551; (6) J. A. S. Smith and D. A. Tong ibid. p. 173; ( c ) ibid. p. 178; ( d ) D. R. Armstrong P. G. Perkins and J. J. Stewart ibid. p. 3674 The Typical Elements 279 atom is consistent with the n-bonding character decreasing in the sequence BI > BBr N BCl . The variation in the 0- and n-bond character of the B-C1 bonds and the extent of s-hybridization have also been e ~ t i m a t e d . ' ~ ~ ~ ' ~ The electronic structures of BCl, B2C14 B4C14 and BIoH14 have been examined using an improved SCMO method and the stability of B4C14 has been suggested to arise from a build-up of charge within the B tetrahedr~n."~~ N.m.r. studies have included the 'B and "F spectra of boron trifluoride in the gas phaselo6" and the ' 'B spectra of several mixed trihalides BXYZ (X Y Z = F C1 Br or I), which show reasonable agreement between calculated and experimental values of j ( 1 1~-~).106b,c Boron tri-bromide and -iodide are useful reagents in that they react with metal chlorides or oxides to produce the corresponding bromide or iodide of All'', Tl' Sn"' AS'" Sb'" SbV Bill' Ti"' Ti" Zr" Hf" VIII NbV TaV MoV, Wv' Fe"' Co" Ni" PtlV Cu" and Cdli.lo7' Similar reactions of BBr and Ph,BBr with the nickel compound (Ph,P),Ni(C,H,) yield (Ph,P),NiBr and [(Ph,P),Ni(BPh,),$Et20], (where n 2 2) respectively; the latter in the dimeric form probably contains bridging > BPh Boron tri-fluoride and -chloride react with totally dehydroxylated silica probably through reactions at a siloxane bridge site Si-0-Si to produce species which contain -Si-O-BX, and FSi-X (X = F or C1) groups.1o7c Free radicals such as the stable nitroxyl radical form molecular complexes with both boron and aluminium halides and the 14N spin-density term obtained from the e.s.r.spectra of such complexes suggests that the electron-accepting ability increases AlCl z BF < BCI < BBr3.108" The "F n.m.r. spectra of a series of complexes of BF with substituted aromatic amine oxides often show a quartet signal but sometimes a singlet if ligand exchange is occurring.'08b A reduction in the B-F bond dissociation energy determined mass spectro-metrically is found when BF is complexed with diethyl ether.lo8' The structure of diboron tetrachloride B,C1 appears to change from a non-planar to planar form on going from the liquid to solid state as deduced from variations in the vibrational spectra.'09" An interesting reaction of B2C14 and B2F4 with trivinylborane results in addition to one or two vinyl groups although the 2 1 complex (CH,=CH)B[CH(BCl,)CH2BC12]2 is unstable above 195 K.The 1 1 product undergoes several reactions as shown in Scheme 4.'09b 'Oh ( a ) W. S . Hinshaw and P. S. Hubbard J . Chem. Phys. 1971,54,428; (6) M. F. Lappert, M. R. Litzow J. B. Pedley T. R. Spalding and H. Noth J . Chern. SOC. ( A ) 1971,383; ( c ) M. F. Lappert M. R. Litzow J. B. Pedley and A. Tweedale ibid. p. 2426. l o ' ( a ) P. M. Druce and M. F. Lappert J . Chern. Soc. ( A ) 1971 3595; (b) C. S. Cundy and H.Noth J . Organornetallic Chern. 1971,30 135; ( c ) B. A. Morrow and A. Devi, Chem. Cornrn. 1971 1237. (a) T. B. Eames and B. M. Hoffman J . Arner. Chern. SOC. 1971 93 3141; (b) R. S. Stephens S. M. Lessley and R . 0. Ragsdale fnorg. Chem. 1971 10 1610; ( c ) C. B. Murphj and R . E. Enrione Chem. Comm. 1971 1622. I o 9 (a) J. R. Durig J . E. Saunders and J. D. Odom J . Chern. Phys. 1971 54 5285; (b) A. K. Holliday and R. P. Ottley J . Chem. Soc. ( A ) 1971 886; (c) J. J. Ritter T. D. Coyle and J. M. Bellama J . Organornetallic Chem. 1971 29 175; ( d ) M. J. Biallas, Inorg. Chern. 1971 10 1320; (e) B. W. C. Ashcroft and A. K. Holliday J . Chem. Soc. ( A ) 1971 2581 280 D . W . A . Sharp M . G . H . Wallbridge and J . H . Holloway C1,BCH =CHBCI, ii /* 4 i (vin),B I (vin),B[C(H)BCl .C(H),BCl,] X,B[C(H)BCI2C(H),BCl2] \" Me,N,B(vin),H Reagents i B,CI ; ii heat ; iii BX ; iv NMe ; vin = CH =CH -; x = c] or NMe,. Scheme 4 The existence of vinyldihalogenoborane intermediates appears likely in the addition of B,Cl to vinyl chloride and halogeno-olefins in general to produce Cl,BCH,CH(BCl,) ,lo,' and addition of B2C14 (and B2F4) across the unsaturated bond in cyclohexene yields a similar product cis-l,2-bis(dihalogenoboryl)-c y c l ~ h e x a n e . ' ~ ~ ~ The fluoride BzF4 forms 1 1 and 1 2 complexes e.g. Me,N,BF,.BF ,NMe with amine ligands. The photoelectron spectrum of B,CI, which complements the theoretical calculations discussed above shows six bands from 10.60 to 19.51 eV. The strongest three bands are assigned to ionizations from the n-orbitals on the chlorine atoms and the three others to the B4C1 fragment.There appears to be significant back-bonding from C1-+ B which may provide the charge necessary to stabilize the B framework.' The purple form of B8Cl8 has been isolated from the slow decomposition of BzC14 at 353 K and X-ray evidence shows that this form is identical with the red one isolated previously. lob The sub-bromides B,Cl,Br B7Br7 and B,Br have been reported although as yet they have only been identified from mass spectrometric measurements.' OC A study of the n.m.r. spectra of an aqueous solution of fluoroboric acid HBF, has shown that the 19F nuclei are participating in exchange processes which are responsible for the collapse of the 'B spin multiplet.' la Phase relationships in the systems NaF-NaBF KF-KBF, and NaF-KF-BF have been reported, together with methods for the preparation of the pure fluoroborates.' ' lb>' The stability constants for mononuclear complexes successively formed as fluoride ion is added to boric acid," ld B(OH) + [B(OH),F]- + BF4- have been deter-mined.Heterocyclic Compounds containing Boron. There has been a noticeable increase in the number of reports dealing with this class of compounds and although many refer to borazine derivatives several new systems have been prepared. The compounds here are arranged as far as possible according to increasing atomic number of the ring atoms ; thus B-C systems are followed by those containing B-C-N then B-N and B-0 although some overlap inevitably occurs.O ( a ) D. R. Lloyd and N. Lynaugh Chem. Comm. 1971,627 ; (b) G. F . Lanthier J. Kane, and A. G. Massey J . Inorg. Nuclear Chem. 1971 33 1569; ( c ) J. Kane and A. G. Massey ibid. p. 1195. ( a ) G. E. Stungis and J. H. Rugheimer J . Chem. Phys. 1971,55,263; (6) C . J. Barton, L. 0. Gilpatrick J. A. Bornmann J . H. Stone T. N. McVay and H. Insley J . Inorg. Nuclear Chem. 1971 33 337; (c) C. J. Barton L. 0. Gilpatrick J. A. Bornmann, T. N. McVay and H. Insley ibid. p. 345; ( d ) S. L. Grassino and D. N . Hume ibid., p. 421 The Typical Elements 28 1 As mentioned in the Introduction a parent anion (23) in the borabenzene series has been prepared from the diacetylene HC-C-CH,-C-CH through a ring closure reaction with dialkyltin dihydrides followed by replacement of the tin with boron using PhBBr .25 The corresponding 9-boro-anthracene anion (24) has also been obtained as the mesityl derivative.'12" Calculations on this type of boron analogue of aromatic hydrocarbons have been made and good agreement has been obtained between predicted and experimental results for such properties as electronic spectra and ionization potentials.' 2b The electronic spectra for some 7-bora-derivatives of naphthalene phenanthrene and tri-phenylene have been reported and compared with those of the parent hydro-carbon.' ' ,' An extended series of paramagnetic borabenzene complexes of cobalt Co(C,H,BR), first reported last year have been prepared with R = Ph, Me Br OH or OMe.' 12d The reagent Li,CH reacts with (Me,N),BCl to give predominantly the cyclic trimer (R,NB-CH,), together with a small yield of (Me N) B - C H - B( NMe,) .' ' + ,R3 N-N 0 a RZ-c,N,B-R4 /I \\ I R' Ph mesityl ( 2 3 ) (24) ( 2 5 ) Several heterocycles containing a cyclic system of B-C-N atoms have been reported including rings of BCN, BC,N, BC,N BC,N, and BC,N atoms. The boron analogue of imidazole (25) has been prepared from boronic acid derivatives RBX (X = C1 OMe OEt OH or NMe,) the compounds showing some aromatic character as was found for the tetraphenyl derivatives reported previously.' 14" Ring expansion occurs when the cyclic compound Phk-NMe-(CH,),-fiMe reacts with PhNCS and (26) is f~rrned."~' The five-membered ring compound HB-(CH,),-NR (R = Pr or Bu) results from the action of methanol on the reaction products from triethylamine-borane and R(H)N-CH,-CH=CH ,11 5o and convenient syntheses of various derivatives of the systems (27)'15' and (28)",' have also been described.MeN NMe S=C\ /BPh N Ph (26) R' I (a) R . Van Veen and F. Bickelhaupt J. Organametallic Chem. 1971 30 C51 ; ( b ) J . Michl Coll. Czech. Chem. Comm. 1971 104 1248; ( c ) ibid. p. 1233; ( d ) G. E. Herberich G . Greis H. F. Heil and J. Muller Chem. Comm. 1971 1328. P. Krohmer and J. Goubeau Chem. Ber. 1971 104 1347. l 4 (a) M. J . S. Dewar R . Golden and P. A. Spanninger J . Amer. Chem. SOC. 1971 93, 3298; (6) M. K. Das P. G. Harrison and J. J. Zuckerman Znorg. Chem. 1971,10 1092. ' I s (a) V. A. Dorokhov 0. G. Boldyreva and B. M. Mikhailov Zhur. obshchei Khim., 1970 40 1528; (b) H .Bellut C. D . Miller and R . Koster Syn[hesis Inorg. Metal-org. Chem. 1971 1 8 3 ; ( c ) H. L. Yale J . Heterocyclic Chem. 1971 8 1Y3. I1 282 D . W . A . Sharp M . G . H . Wallbridge and J . H. Holloway New complexes derived from the pyrazolylborato-type ligands have been prepared for ruthenium,' '6a manganese and rhenium,' 16' namely HB(N,C,-H,),Ru(CO),X (X = C1 Br or I) and H,B(N,C,H,),M(CO),(pyrazole) (M = Mn or Re). The crystal structures of the related systems H,B(N,C,Me,H),-Mo(CO),(n-C,H,)' ' 7a (29) and HB(N,C,H,),MO(CO)~NNP~' ' 7b have been * H H determined. In both cases the metal atom is in a slightly distorted octahedral co-ordination ; in the former the sixth co-ordination position is apparently occupied by the hydrogen atom in view of the short Mo-H distance (230 pm).X-Ray data for the cation in [{ FB(ONCHC5H3N),P}Fe1']+BF4- show the six nitrogen atoms around the iron atom to be arranged in a geometry between that of a trigonal prism and an octahedron suggesting appreciable ligand distortion by the Fe" since the ligand usually favours the former geometry.'17' A further crystal structure determination on triethanolamineborate N(CH,CH,O),B, confirms the triptych structure with a B-N bond distance of 165pm and tetrahedral symmetry around the boron atom.' 17d In the borazine class of compounds discussions concerning the sequence of orbital energies have been resolved since two reports of the photoelectron spectra of borazine and trimethylborazines have suggested that the highest-lying occupied orbital is of the n-type and not the a-type as indicated from calcula-tions.' 18'vb Examination of the mass spectra of N-substituted trialkylborazines B,H,N,R (R = Et Pr" Pr' Bun Bus Bu' or Bu') has shown that the major initial fragmentation consists of the loss of an alkyl radical from the a-carbon atom of an N-substituted group.'lga A series of protonated borazines ' ' ( a ) M.I. Bruce D. N. Sharrocks and F. G . A. Stone J . Organometallic Chem. 1971, 31,269; (6) A. Bond and M. Green J . Chem. SOC. ( A ) 1971,682. '" ( a ) C. A. Kosky P. Ganis and G. Avitabile Acta Cryst. 1971 B27 1859; (b) G. Avitabile P. Ganis and M. Nemiroff Acta Cryst. 1971 B27,725; ( c ) M. R. Churchill and A. H. Reis Chem. Comm. 1971 1307; ( d ) Z. Taira and K. Osaki Inorg. Nuclear Chem.Letters 1971,7 509. 'I8 ( a ) D. R. Lloyd and N. Lynaugh Chem. Comm. 1971 125; (b) H. Bock and W. Fuss, Angew. Chem. Internat. Edn. 1971,10 182. ' l 9 ( a ) P. Powell P. J. Sherwood M. Stephens and E. F. H. Brittain J . Chem. Soc. ( A ) , 1971 2951 ; (b) R. F. Porter and J. J. Solomon J . Amer. Chem. SOC. 1971 93 56 The Typical Elements 28 3 [B3H3N3H4]+ are observed from a mass-spectrometric investigation of gas-phase ion-molecule reactions of methane ethane and n-butane with borazine.' 19b Convenient syntheses of B-trichloro-N-trimethyl- and N-trialkyl-borazines have been described; the former result from the reaction of a mixture of BCl and MeNH2,ItoU and the latter synthesis is similar to that described above for a m i n ~ b o r a n e s ~ ~ ~ except that a primary amine is used in the reaction mixture.'20b Several mono-€3-substituted borazines have been prepared from the action of silver salts (AgX where X = CN NCO O,CCF, F NO, etc.) on borazine,'20c and similar derivatives of N-trimethylborazine have been obtained from reactions with heavy-metal halides such as TiCl, SnCl, and HgCl .It is also possible to place groups such as -Mn(CO) and -C5H5 on to the boron atoms in borazine by interaction of B-trichloroborazine with the respective sodium salts NaMn(CO) and NaC,H .120e The cyclic BAl,N system (30) which may dB\ Me H (30) be considered to be formally isoelectronic with cyclohexane is proposed 1 2 ' to be the product of the reaction of trimethylalane with excess HB(NMe,) . Studies relating to the mechanism of borazine formation from boron trichloride or its phenyl derivatives and aromatic amines suggest that a catalyst such as a tertiary amine is necessary for the cyclization reaction to occur.122u,b The 1,4,5-trimethyl derivative of the A2-tetrazaboroline ring BN has been shown to act as a donor system towards acceptors such as BCl TiCl, and SbC1 forming a variety of complexes e.g.BCl ,Me,N,BMe and 2TiC1,,1.5Me2-N,BMe.' The interaction with TiC1 in solutions of aromatic hydrocarbons has been investigated in more detail and the complexes formed incorporate the solvent e.g. 4TiC1 ,2Me,N,BMe,L (L = benzene o-xylene or naphthalene).' 2 3 b The B2N3 ring compound (31) results from the action of R'NH (or NH,) on the borane derivative MeS-B(R2)-N(R3)-N(R3)-B(R2)SMe (R' = H or Me, 'O ( a ) I .A. Boenig and K. Niedenzu Synthesis Inorg. Metal-org. Chem. 1971 1 159; (6) E. C. Ashby and R. A. Kovar Inorg. Chem. 1971 10 1524; (c) 0. T. Beachley, J . Amer. Chem. SOC. 1971 93 5066; ( d ) G. A. Anderson and J. J. Lagowski Inorg. Chem. 1971 10 1910; ( e ) D. T. Haworth and E. S. Matushek Inorg. Nuclear Chem. Letters 197 1 7 26 1 . R. E. Hall and E. P. Schram Inorg. Chem. 1971 10 192. ( a ) J. R. Blackborow J. E. Blackmore and J. C. Lockhart J . Chem. SOC. ( A ) 1971,49; ( 6 ) J. R. Blackborow and J. C. Lockhart ibid. p. 1343. ( a ) B. Hessett J. H. Morris and P. G. Perkins J . Chem. SOC. ( A ) 1971 2466; (b) B. Hessett J. H. Morris and P. G. Perkins ibid. p. 2056. *' 284 D . W. A . Sharp M . G . H . Wallbridge and J . H . Holloway R2 = R3 = Me or Ph),'24a and the BC,S ring (32) is formed when Me,S,BH, H2C-CH2 R3 N-N I \ I \ N S I I R' Me R3 \ R2-B ,B-R2 H,C\ p 3 2 (31) (32) is allowed to react with H2C=CHCH,SMe.'24b A B0,C3 ring results from the reaction scheme :' 24c Ye O-C6+ O-Cd+ \ Me -1 \ + Et2B /CH2 Ac,CH BEt + HNAc -+ Et,BOC(Me)=NAc Metal Borides and Boron Nitride.The metal borides of V Cr Fe Co and Ni have been prepared by treatment of the metallic sulphide with a mixture of boron trichloride and hydrogen at 773-1273 K.12" The complex borides Hf,Mo3B - x (x z i) and (Hf,W),,B,- (x z i) have been detected in mixtures of H ~ - ( M o W ~ B . ' ~ ' ~ Mass spectral data have indicated the existence of UB, UB, and CeB,lZsc and from the "B n.m.r. spectra of powdered samples of P-rhombo-hedral boron boron carbide,lZsd and A1B,'25' at 300K the results for boron carbide have been interpreted in terms of a formula (B,,C)(CBC) [rather than (B12)(CCC) as usually given] with a carbon atom occupying a site in the icosa-hedron.1 2 5 d The action of metal oxides on borides in the mixtures CrB,-Cr,03 , TaB,-Ta,O, and NbB,-Nb20 has led to the isolation of the new phases CrB, TaB and NbB (with Nb3B2) r e ~ p e c t i v e l y . ' ~ ~ ~ A synthesis of the cubic form of boron nitride has been achieved by heating hexagonal BN in the presence of various catalysts (tin alloys or magnesium) at 2473 K for 30 min at - 80 kbar pressure. The crystal size of the product varies from 1@-100pm.'26 Aluminium.-As last year the main bulk of the papers published are concerned with compounds containing aluminium-carbon bonds although aluminium hydride derivatives continue to be of interest.l z 4 ( a ) D . Nolle and H. Noth Angew. Chem. Internat. Edn. 1971,10 126; ( 6 ) R. A. Braun, D . C. Brown and R. M. Adams J . Amer. Chem. Soc. 1971 93 2823; (c) V. A. Dorokhov L. 1. Lavrinovich and B. M. Mikhailov Doklady Akad. Nauk S.S.S.R., 1970,195 1100. ( a ) J. Gueilleron G. Lahet F. Thevenot and R. A. Paris J . Less-Common Metals, 1971,24 317; ( b ) P. Rogl H. Nowotny and F. Benesovsky Monatsh 1971 102 971 ; (c) K. A. Gingerich J . Chem. Phys. 1971 55 746; ( d ) T. V. Hynes and M. N. Alexander ibid. p. 5296; ( e ) J. P. Kopp and R. G. Barnes ibid. p. 1840. 1 2 6 M. Ushio H. Saito and S. Nagao Kogyo Kagaku Zasshi 1971 74 598 (Chem.Abs., 1971 75 44 41 In) The Typical Elements 28 5 Compounds containing Al-H Bonds. The synthesis and reactions of aluminium hydride have been reviewed.',' New complexes have been prepared' with various stoicheiometries (AlH ligand) as shown by quinuclidine (1 1 and 1 2) 1,4-dimethylpiperazine (1 l) and NNN'N'-tetramethyl-o-phenylene-diamine (1 1) complexes and the heats of formation of these fall in the range 16&180 kJ mol- ' (except for the last mentioned which is possibly polymeric). These values are similar to those for other tripositive aluminium and gallium compounds. The complexes AlH,,NR (R = Me or Et) have been shown to be monomeric in a dilute benzene solution,' 28b and preliminary crystal structure determinations on the compounds where R = n-C,H and n-C,H confirm the expected tetrahedral symmetry around both the aluminium and nitrogen atoms.128c A study of the properties of the chlorohydride complexes AlH,-,Cl,,L (L = Et,O Me,N or Et,N; x = 1 or 2) substantiates earlier reports on this type of compound.'28d Other earlier work on the interaction of secondary amines with lithium aluminium hydride has been investigated in more detail and the compounds formed at various stages of the reaction have been identified as Li,AlH, LiAl,H,NR, (R,N),AlH LiAlH(NR,) and LiAl(NR,), (R = Et Pri or C,H,1).'29a Other substituted derivatives of the AlH,- ion include Li[Al(C,F,H),H,-,] (x = 1,2 or 3)'29b and the phosphine compounds Li[Al(HPMe),H] and Li(Al[P(SiH,),],},' 29c obtained from lithium aluminium hydride by the action of 1,2,4,5-C,F4H, MePH and P(SiH,) respectively.A direct synthesis of amino-alanes has been achieved from aluminium and secondary amines under hydrogen pressure. 29d A1 + 5H2 + nR,NH -+ H3-,AI(NR2) + nH, (R = Me,Et,C,H,,,C,H,,orPr';n = 1or2) Compounds containing Al-C Bonds. A determination' of the structures of the monomeric and dimeric forms of trimethylalane from electron diffraction data, shows the existence of a planar monomer with freely rotating methyl groups and two bridging methyl groups in the dimer which has D, symmetry and Al-C (terminal) = 196 pm Al-C (bridge) = 214 pm. The small vibrational ampli-tude of the bridging carbon atom would appear to argue against the model which contains a bridging hydrogen atom and such a conclusion is supported by n.q.r.studies on a series of trialkyl- and triaryl-alane~.'~~' The Raman 1 2 ' S. Cucinella A. Mazzei and W. Marconi Znorg. Chim. Acta Rev. 1970 4 51. ( a ) N. N. Greenwood and B. S. Thomas J . Chem. SOC. ( A ) 1971 814; (b) K. N. Senienenko E. B. Lobkovskii B. M. Bulychev and A. L. Dorosinskii Russ. J . Znorg. Chem. 1971 16 804; (c) ibid. p. 923; ( d ) L. I. Zakharkin V. V. Gavrilenko and D. N. Maslin Zhur. obshchei Khim. 1971,41 577. 1 2 9 (a) R. G . Beach and E. C. Ashby Znorg. Chem. 1971 10 1888; (b) R. S. Dickson and G . D. Sutcliffe Austral. J . Chem. 1971 24 295; (c) J. W. Anderson and J. E. Drake J . Chern. Soc. ( A ) 1971,2246; ( d ) R. A. Kovar and E. C. Ashby Znorg. Chem., 1971 10 893. 1 3 0 ( a ) A. Almenningen S. Halvorsen and A.Haaland Acta Chem. Scand. 1971 25, 1937; (6) M. J. S. Dewar D . B. Patterson and W. I. Simpson J . Amer. Chem. SOC., 1971,93 1030 286 D. W . A . Sharp M . G . H. Wallbridge and J . H . Holloway spectrum of the monomeric AlMe molecule has also been recorded and com-pared with that of the monomeric BMe, the results showing that the force constant of the M-C bond decreases in the order B > A1 > Ga > In.'31a The structure of dimeric (Me,AlH) at 443 K also determined from electron-diffraction data is similar to that of Al,Me, except that the hydrogen atoms now form the bridge bonds the Al-H distance being 176pm and the A1-H-A1 angle being 103".131b Another compound which is to contain bridging methyl groups from i.r. and Raman data is LiAlMe, where a con-tinuous chain forms as [=Li=(CH,),=Al=(CH,),=],.The crystal structure, from X-ray data of the dimeric tricyclopropylalane is interesting in that the bridging cyclopropyl groups form a puckered Al,C ring (33). In the methyl-substituted compound Al,(c-C,H,),Me, a rotational inversion of the bridging cyclopropyl groups has been ~ u g g e s t e d ' ~ ' ~ to explain the equivalence of the terminal methyl groups in the 'H n.m.r. spectrum at 244 K. The co-ordination of a base to trimethylalane as in Me,N,AlMe, has been shown to result in an increase in both the Al-C and N-C bond distances but electron-diffraction data confirm the nearly tetrahedral symmetry expected around both the aluminium and nitrogen atoms in both this and the similar compound formed with quinuclidine.' le n (33) The heats of dissociation of liquid trimethyl- and triethyl-alane have been determined as 69.3 and 33.6-58.8 kJ (mol of dimer)- ' and kinetic results suggest that the lower limit of the latter value is more appr~priate.'~~" The o-bonded benzyl groups in monomeric Al(CH,Ph) do not show any fluxional behaviour, as deduced from the 'H n.m.r.spectrum between 183 and 298 K,132b but in con-trast to this tri-m-(and p-)tolylalanes (MeC,H,) A1 undergo an o-arylation 1 3 ' (a) R. J. O'Brien and G. A. Ozin J. Chem. SOC. ( A ) 1971 1136; (b) A. Haaland, G . A. Anderson A. Almenningen and F. R. Forgaard Chem. Comm. 1971 480; ( c ) J. Yamamoto and C. A. Wilkie Inorg. Chem. 1971 10 1129; ( d ) J. W. Moore, D. A. Sanders P. A. Scherr M. D. Glick and J.P. Oliver J. Amer. Chem. SOC. 1971, 93 1035; (e) C. D. Whitt L. M. Parker and J. L. Atwood J. Organometallic Chem., 1971 32 291. 1 3 2 (a) J . N. Hay P. G. Hooper and J. C. Robb J . Organometallic Chem. 1971,28 193; (6) J. J. Eisch and J. M. Biedermann ibid. 1971 30 167; (c) J. J. Eisch and J. L. Considine ibid. 1971 26 C1 The Typical Elements 287 rearrangement on irradiation involving a hydride transfer to the metal atom to yield an o-substituted derivative (34).'32c The reaction of A1-C bonds with alkynes has been shown to involve ~is-addition,'~~'' although with cyclo-octa-175-diene and BuiA1 the reaction does not yield cyclo-octane but instead both cis- and trans-1,2-substituted cy~lopentanes.'~~~ The reaction of BuiA1 with cyclopentadiene at 150 "C which probably involves some BU; AlH affords the a-cyclopentadienyl derivative Bu\AlC,H,,' 33c and a similar product is obtained from the action of the pure hydride on hex-l-e11-5-yne.'~~~ Both alkenyl bridging groups and mixed alkenyl-hydrogen bridges have been identified in the products from the action of dialkylaluminium hydrides on hex- 1 -yne.' 3e f=J 6 C,H (cot 3w- I AlMe I 2 Me,AI +- W(CO),C,H, Me (35) Me (34) Alkyl- and aryl-aluminium halide compounds have been prepared by the exchange of alkyl groups between PbMe and organoaluminium compounds' (although further studies have shown that complexes of the type Me,PbCl,, 2MeAlC1 may be formed'34b) and of aryl groups between AlPh and aluminium halides,' 34c or by use of alkylammonium halides.' 34d Et,AI + Me,NH,+Br- + Et,AIBr,NHMe + C2H, Several ions derived formally from the [AlRJ- and [Al,R,]- species e.g. NMe,+X- [X = Me,A1,N3 or Me,AlN,] have been prepared from the action of NMe,+Y- [Y = N, SCN CN or C(CN),] salts on trialkyl-alanes (and -gallanes). ' Novel compounds containing aluminium (or indium) bonded either directly or indirectly to Cr Mo or W have been prepared e.g. [R,Al(or In)W(C0)3(C,H,)]-,136a R',AlMo(or W)(CO),(CSHs)L136bic (39 and 1 3 3 ( a ) J. J. Eisch and C. K. Hordis J. Amer. Chem. SOC. 1971 93 2974; ( b ) E. Marcus, D. L. MacPeek and S. W. Tinsley J. Org. Chem. 1971 36 381 ; (c) W. R. Kroll and B. E. Hudson J. Organometallic Chem. 1971 28 205; (d) G. Zweifel G. M. Clark, and R. Lynd Chem. Comm. 1971 1593; ( e ) G. M. Clark and G.Zweifel J. Amer. Chem. SOC. 1971,93,527. 1 3 4 ( a ) M. Boleslawski S . Pasynkiewicz and K. Jaworski J. Organometallic Chem., 1971 30 199; (6) M. Boleslawski S. P. Pasynkiewicz and H. Pszonka ibid. 1971 28, C31; (c) G. V. Zerina N. I. Sheverdina A. N. Rodionov and K. A. Kocheshkov, Doklady Akad. Nauk S.S.S.R. 1971 197 830; ( d ) K. Gosling A. L. Bhuiyan and K. R. Mooney Znorg. Nuclear Chem. Letters 1971 7 913. 1 3 5 F. Weller I. L. Wilson and K. Dehnicke J. Organometallic Chem. 1971 30 C1. 1 3 ' (a) J. M. Burlitch and R. B. Petersen J. Organometallic Chem. 1970,24 C65; ( b ) W. R. Kroll and G. B. McVicker Chem. Comm. 1971,591 ; (c) R. R. Schrieke and J. D. Smith, J. Organometallic Chem. 1971 31 C46; ( d ) R. B. Petersen J. J. Stezowski C. Wan, J. M. Burlitch and R.E. Hughes J. Amer. Chem. Soc. 1971 93 3352; (e) A. Storr and B. Thomas Canad. J. Chem. 1971,49 2504 288 D . W. A . Sharp M . G . H . Wallbridge and J. H . Holloway AI[W(CO)3(C5H,)]3,(C,H,0),'36d (R = Ph; R' = Me Et or Bu'; L = CO or PPh,) some of which probably contain an A1 t 0-C-M (M = Mo or W) bridging system whereas others including the indium compound appear to possess a direct metal-metal bond. The basicity of the metal atom in the hydride compounds (C,H,),MH (M = Mo or W) has been further demonstrated by the formation of 1:l complexes with AIR (R = Me Et or Ph) or Me,AlH. Several of these complexes eliminate alkane slowly at 298 K and the products appear to be p~lymeric.'~~' The crystal structure of the dimethylaluminium compounds Me,Al.OC(Ph)-(NPh).Me,NO shows a tetrahedral arrangement around the metal atom.'37" and a similar three-co-ordinate derivative Me,Al.OC(OMe) (NPh) shows a 1,3-shift to Me,Al.N(Ph)C(OMe) 0.137b The action of trimethylindium on Me,AI,N(PR,).SiR,.N(PR,) yields the cyclic cation (36) and the InMe -anion,1380 and a series of volatile cyclic imino-compounds [&2-(CH2)x-N-MR,] (x = 1 2 3 or 4; M = Al Ga or In; R = Me Et or Bu') have been prepared and the effects of varying x M and R on the degree of association have been assessed.138b The crystal structure of LiAI(N=CBu\) consists of the aluminium atom surrounded by a distorted tetrahedron of N=CBu' groups two of which bridge the two metal atoms while the other two are terminally bonded with appreciable N A1 (p -+ d) n-bonding.' 39a Ring closure occurs in N-benzylaminoalanes on warming when the o-position of the phenyl ring be-comes bonded to the aluminium atom.'39b R2Si + AIMe, 'N' I PR3 (36) Compounds containing A1-0 Bonds.The hydration number of Al"' has been shown from n.m.r. studies to be near to 6 in both dilute and concentrated soh-ti on^,'^'' and the volume occupied by the water molecules of hydration has been calculated to be less than the volume of an equal amount of bulk water.'40b Other studies on AlC1,-EtOH solutions suggest that at 253 K only 4 molecules of EtOH solvate the Al"' ions but it is probable that some association of the solvated 1 3 ' ( a ) Y. Kai N. Yasuoka N. Kasai M. Kakudo H. Yasuda and H. Tani Chem. Comm. 1971 940; ( 6 ) T. Hirabayashi T. Sakakibara and Y.Ishii J . Organometallic Chem. 1971,32 C5. 1 3 ' ( a ) W. Wolfsberger and H. Schmidbaur J . Organometaffic Chem. 1971 27 181; (6) A. Storr and B. S. Thomas J . Chem. Soc. ( A ) 1971 3850. 139 ( a ) H. M. Shearer R. Snaith J. D. Saverly and K. Wade Chem. Comm. 1971 1275; (b) H. Hoberg Annalen 1971 746 86. (a) J. W. Akitt J . Chem. SOC. ( A ) 1971 2865; (6) ibid. p. 2347; (c) H. Grasdalen, J . Magn. Resonance 1971 5 84; (6 J. W. Akitt N. N. Greenwood and G. D. Lester, J . Chem. Soc. ( A ) 1971,2450 The Typical Elements 289 ions occurs.14oc The 27Al and 31P n.m.r. spectra of phosphoric acid solutions of Al"' ions indicate the presence of monomeric e.g. Al(H,P0,)3 + A1(H2P0,)2 +, and Al(H,PO,),+ and polymeric species e.g. [A1(H,P0,)J3+ where n 2 2.140d Several studies have been concerned with intramolecular rearrangement processes in labile /3-diketonates of Al"'.Thus in tris-(2,6-dimethylheptane-3,5-dionato)aluminium(Iir) two signals from the Pr' groups are observed in the 'H n.m.r. spectrum probably arising from the total molecular dissymmetry at the aluminium atom. l4 l a Similar studies on tris-( l-pheny1-5-methylhexane-2,4-dionato)aluminiurn(~~~)'~~~ and Al(acac),(hfac) - x (acac = acetylacetonate ; hfac = hexafluoroacetonate; x = 1 or 2)l4lC have suggested a five-co-ordinate intermediate through the breaking of one A1-0 bond in the rearrangement reaction. The nature of tri-isopropoxyaluminium has been investigated by i.r. and Raman techniques and it appears that in the low-melting solid and the freshly heated liquid trimeric species predominate whereas in aged liquids and the high-melting solid there is a proportion of a tetramer present which has a six-co-ordinate aluminium atom.142a The heat of formation AHf of the tetrameric form has been determined as - 5149 kJ mol-',142b and phase studies on Al(OPr') or Ga(OPr'),-pyridine systems show the existence of a 1 1 complex with the gallium compound but a 2A1(OPri) :C,H,N complex with the aluminium.42c A volatile hexafluoroisopropoxide compound of aluminium has been prepared and mass spectral data indicate that it is The ethoxide compound NaAl(OEt) is partially ionized in ethanol solution but extensive ion-pairing occurs at high concentrations. The dehydration of tohdite (5A120 ,H20) leads to K'- and K-A~,O ,14,' and the crystal structure of the former from X-ray data shows the oxygen atoms to be arranged in a close-packed structure as in tohdite with the aluminium atoms statistically distributed over the octahedral and tetrahedral positions.Compounds containing Al-Halogen Bonds. The equilibrium constant for the dissociation 2AlC1,- S A12C1,- + C1- in molten NaCl-AlCl has been measured potentiometrically over the temperature range 448-673 K and the interactions in a mixture of NaC1-AlCl have been studied from the variation in the conductivity over the range 428-468 K.144b The structures of the complexes A1Cl3,1.5L (L = MeCN or HC0,Me) and AlC13,2L (L = Me20 or MeCN) "I ( a ) B. Jurado and C. S . Springer Chem. Comm. 1971 85; ( b ) J. R. Hutchinson J. G. Gordon and R.H. Holm Znorg. Chem. 1971 10 1004; (c) D. A. Case and T. J. Pinnavaia ibid. p. 482. 1 4 2 ( a ) W. Fieggen and H. Gerding Rec. Trau. chim. 1971 90 410; ( 6 ) J. W. Wilson, J . Chem. Soc. ( A ) 1971,981 ; ( c ) J. G . Oliver and I. J. Worrall J . Inorg. Nuclear Chem., 1971 33 1281 ; (d) K. S. Mazdiyasni B. J. Schapter and L. M. Brown Inorg. Chem., 1971 10 889; ( e ) J. T. Fenwick and J. W. Wilson Inorg. Nuclear Chem. Letters, 1971 7 341. 1 4 3 ( a ) M. Okumiya G. Yamaguchi 0. Yamada and S. Ono Bull. Chem. Soc. Japan, 1971 44 418; ( b ) M. Okumiya and G. Yamaguchi ibid. p. 1567. 14' ( a ) G. Torsi and G. Mamantov Inorg. Chem. 1971 10 1900; (b) R. C. Howie and D. W. Macmillan J . Inorg. Nuclear Chem. 1971 33 3681 ; (c) D. E. H. Jones and J. L. Wood J . Chem. Soc.( A ) 1971 3135 290 D . W . A . Sharp M. G . H . Wallbridge and J . H. Holloway vary in that i.r. and Raman data suggest that only AlCl3,2Me2O is an undis-sociated trigonal-bipyramidal structure and that the rest are ionic compounds, whereas AlCl ,2MeCN has uncombined ligand in the 1 a t t i ~ e . l ~ ~ ~ Gallium and Indium.-The existence of several hydrates and variations in the co-ordination shell around the gallium atom have been observed in GaX,-H,O (X = C1 or Br) systems. Whereas GaBr forms five hydrates GaBr ,xH,O (x = 1, 2 3 4 or 15) in GaC1,-H,O only a monohydrate was positively identified.'45" When indium(Ir1) halides are dissolved in water-acetone mixtures then at 173 K both free and complexed water may be observed in the 'H n.m.r. spectra. When the corresponding halide ion is added to the solutions the iodide exists as In(H,0),3+(InI,-), but for the chloro- and bromo-compounds only the InX,-ions could be dete~ted.'~~' Anhydrous nitrato-complexes of Ga"' Al"' and Fe"' have been prepared using N,O ,146a e.g.Raman and i.r. spectra suggest that unidentate nitrato-groups are involved e.g. [Ga(ONO,),] - . Monomeric silylamide derivatives M[N(SiMe,),] (M = Al, Ga or In) have been prepared from the action of LiN(SiMe,) on the appropriate chloride. X-Ray data have confirmed the existence of In,Se and In,Te, and indicate that the compounds contain the (In,)5+ cation analogous to the recently proposed (Hg,)" ion.'47 Compounds containing Metal-H Bonds. Significant changes in the degree of association have been found to occur in the complexes (RNHGaH,) depending upon the R group.For n-alkyl groups X = 3 but for branched-chain groups the dimeric structure is often preferred. 14*" The crystal structure of the trimeric complex [(CH,),NGaH,] shows the Ga,N ring to be in a chair configuration (37) with a Ga-N distance of 197 pm and angles at the Ga and N atoms of 100" and 12 lo respectively. 14*' The syntheses of the complex hydridogallates MGaH (M = Li Na K Rb Cs Me4N Me,P or Et,As) have been described. 14*' Compounds containing Metal-C and Metal- Halogen Bonds. Co-ordination compounds of this class are discussed in the section below. Uncomplexed trispentafluorophenylindium In(C6F& and some derivatives have been pre-pared. 14'" The kinetics of the decomposition of tri-isobutylgallium have been 1 4 5 ( a ) M.T. Bories J. Raziere and A. Potier Chem. Cornm. 1971 213; (6) A. Fratiello, 14' ( a ) D. Bowler and N. Logan Chem. Cornm. 1971 582; ( b ) H. Burger J. Cichon U . 14' J. H. C. Hogg H. H. Sutherland and D . J. Williams Chem. Cornm. 1971 1568. 148 (a) A. Storr and A. D . Penland J . Chem. Sac. ( A ) 1971 1237; (b) W. Harrison A. Storr and J. Trotter Chem. Comm. 1971 1101 ; ( c ) L. I. Zakharkin V. V. Gavrilenko, and Yu. N. Karaksin Synthesis Inorg. Metal-org. Chem. 1971 1 37. 149 (a) G. B. Deacon and J. C. Parrott Austral. J. Chem. 1971 24 1771 ; (h) K. W. Eggar, J. Chem. SOC. (A) 1971,3603 ; (c) V. I. Shcherbakov S. F. Zhiltsov and 0. N. Druzhkov, Zhur. obshchei Khim. 1970 40 1542. D. D. Davis S. Peak and R. E. Schuster Inorg.Chem. 1971 10 1627. Goetze U. Wannagat and H. J. Wismar J . Organometallic Chem. 1971 33 1 The Typical Elements 29 1 (37) interpreted in terms of a four-centre elimination process,'49b and the thermal de-composition of various ethyl-indium and -thallium compounds containing M-0 and M-N bonds results in disproportionation or formation of the metal.'49' Insertion into the In-C bond occurs in the reaction of trimethyl-indium with sulphur dioxide to yield finally In(SO,Me) ,150a while M-C bond rupture occurs when CH,X (X = Br or I) and CCI react with triethylindium to produce Et,InCH,X and Et,InCCl respectively ;150b 8-quinolinol reacts with Et,Ga to form Et,GaONC,H .I5'' An oxidative addition reaction to InBr occurs with methyl bromide to yield MeInBr in the absence of solvent, and this reaction is obviously capable of being considerably extended.' The thermal decomposition of the gallium iodide Ga,I affords Ga,I which Raman data suggest' 52a is best formulated as (Gaf),Ga216Z - .A possible carbenoid intermediate is involved in the reaction of Ga,Cl with carbon tetra-chloride and it is probable that it is this species rather than the carbene CI,C: itself which reacts with unsaturated substrates. ' 5 2 b c1,c c1 CI \ / \ / Ga,Cl + CCI + Ga Ga -+ C1,C + Ga,Cl, / \ / \ c1 c1 c1 Associated ethoxy-compounds Ga(OEt),X - x (X = C1 or Br ; x = 1 or 2) result from the action of ethanol on the halide Ga,X,.'52' 1 5 " ( a ) A. T. T. Hsieh J . Organometaffic Chem. 1971 27 293; (6) T. Maeda H . Tada, K. Yasuda and R. Okawara ibid.p. 13; (c) B . Sen and G . White lnorg. Nuclear Chem. Letters 197 1 7 79. 1 5 1 L. Waterworth and I . J. Worrall Chem. Comm. 1971 569. 1 5 2 ( a ) L. Waterworth and I. J. Worrall Znorg. Nuclear Chem. Letters 1971 7 611; (6) W. Lind and I . J. Worrall ibid. p. 1 1 5 3 ; (c) J. G . Oliver and I. J. Worrall J . Chem. Soc. ( A ) 1971 2315 292 D . W . A . Sharp M . G . H . Wallbridge and J . H . Holloway Co-ordination Compounds of Gallium and Indium. Several complexes involving the substituted dithiolate dianion have been prepared for metals which are initially in the (1x1) or ( I ) oxidation state e.g. Ga(mnt),,- In(mnt) - In(mnt),X2-, and Tl(mnt),Br- [mnt = C~S-~,~-S,C,(CN),~-],' whereas In' halides form XIn[l,2-S2C,(CF,),] (X = C1 Br or I) which are believed to be polymeric complexes of Other neutral complexes of the type InL (L = 3-hydroxy-2-methyl-4-pyronato or tropolonato anions) may be reduced polarographically in successive one-electron steps similar to the reduction of complexes of mnt, and this may be a general property of complexes with bidentate chelating l i g a n d ~ .' ~ ~ Full details have been given'53e of the crystal structure of (Et4N+) [In(mnt)3]3 - . Anionic halide complexes of both In' and In"' have been prepared. With the former ions of the type InX,,- (X = C1 Br or I) have been obtained which are isoelectronic with SnX,- and SbX ,' 54a whereas with the latter various anions, e.g. InX,- InX,,- InX,3- and InX,4- are formed the ion obtained depending upon the cation solvent and nature of X (X = C1 Br or I).154b Five-co-ordinate complexes of I d are formed with olefinic phosphines and with InI,[P(C,H 1)3]2 Gallium trihalides in acetonitrile form the four-co-ordinate species [GaX,(MeCN),]+ and GaX,- and with pyridine the com-plexes 2GaX ,3C5H,N (X = C1 or Br) have been is01ated.l~~~ The kinetics of the oxidation of In' with Fe"' in different solution conditions have been studied spectroscopically and it is probable that In" is involved as an unstable intermediate.' Compounds containing Indium- Transition-metal Bonds.Unlike In[Mn(CO),] , the substituted compound XIn[Mn(CO),] (X = Cl or Br) does not dissociate to give Mn(CO),- ions in acetonitrile and the stable [InMn(CO),],f ion has been isolated as the perchlorate salt.'57a The insertion of InX (X = C1 or Br) into various compounds has been achieved thus [(C,H,)Fe(CO),] [HgCo(CO),] , and Rh(CO)Cl(PPh,) yield [(C,H,)Fe(CO),],InX XIn[CO(CO),], and possibly X(Cl)InRh(CO)(PPh,) re~pectively.'~~' Both In"' and TI"' have been shown' 57c to be sufficiently strong acids to form the stable tetra-co-ordinated ions M [cO(cO)4 14 - .Ph,AsCo(CO) + M[Co(CO),] -+ Ph,As[M(Co(CO),),] l S 3 ( a ) D. G. Tuck and M . K. Young J . Chem. SOC. ( A ) 1971 214; (b) R. 0. Fields, J. H. Watts and T. J. Bergendahl Inorg. Chem. 1971 10 2808; (c) A. F. Berniaz, G. Hunter and D. G. Tuck J . Chem. SOC. ( A ) 1971 3254; (d) D. G. Tuck and M. K. Young ibid. p. 3100; ( e ) F. W. B. Einstein and R. D. G. Jones ibid. p. 2762. l S 4 ( a ) G. Contreras and D. G . Tuck Chem. Comm. 1971 1552; (6) J.Gislason M. H. Lloyd and D. G. Tuck Inorg. Chem. 1971 10 1907. l S 5 (a) D. M. Roundhill J . Inorg. Nuclear Chem. 1971 33 3367; (b) C. D. Schmulbach and I. Y. Ahmed Inorg. Chem. 1971 10 1902. 1 5 6 R. S. Taylor and A. G. Sykes J . Chem. SOC. ( A ) 1971 1628. 15' (a) A. T. T. Hsieh and M. J. Mays Chem. Comm. 1971 1234; ( 6 ) Inorg. Nuclear Chem. Letters 1971,7,223 ; ( c ) W. R. Robinson and D. P. Schussler J . Organometallic Chem., 1971 30 C5; (6) P. D. Cradwick ibid. 1971 27 251 The Typical Elements 295 high-dielectric solvents such as (Me,N),PO both solvent (S) and metal are incorporated in the lattice and compounds such as Li(S)C,, and Na(S)C,, are formed ;" mixed fluoride-chloride inclusion compounds of the type 3SbF3C1 ,C2, are formed by reacting graphite with SbF in an atmosphere of chlorine or SbF,Cl .2d An apparatus for the production of a high-density stream of hydrogen atoms by a low-frequency discharge method has been described.The hydrogen atoms reduce olefins and react with HCN to form what is probably H,CNH as an intermediate; H2CNH decomposes to NH, CH, C2H6 and higher paraffins on warming.," Pyrolysis of cyanamide under reduced pressure produces carbodi-imide HNCNH which may be isolated in a matrix ; N-N=CH, the other possible isomer is not formed.3b Many transition-metal complexes of the nitroso- and nitro-dicyanomethide ions [XC(CN),] (X = NO or NO,) have been described on polarographic reduction of these ions hydroxylamine is formed.4b The structures and reactivity of some dicyanomethanido- and cyanimido-oxyanions e.g.P0,C(CN)23 - and S0,NCN- have been disc~ssed.~' Fulminic acid HCNO is a stronger acid than HCN and has an acid strength comparable \ / NH H2N 'C+' c1-I 0 / Me to that of HN3;4d bromine isocyanate BrNCO can be prepared as a monomer by condensing the product of the reaction between Br and AgNCO at 77 K.4e Several papers have described properties of aminocarbonium ions. 2-Methyl-pseudourea hydrochloride (38) has an approximately planar cation." Di-methyl(chloromethyl)amine Me,NCH,Cl forms salts Me,N=CH,X- (X = AlCl, SbCl, or SbCl,) with strong Lewis acids;sb some of the reactions of dichloromethylenedimethylammonium chloride Me,N=CCl,Cl- have been described. With active hydrogens e.g. HOPh elimination reactions occur to give e.g.(PhO),C=NMe,Cl - . 5 c The tris(azido)carbonium ion in [C(N,),]SbCl6 is propeller-like and nearly planar but the N-N bond lengths vary widely the cr-N-D-N having a mean value of 139 pm and the P-N-7-N a mean value of 105 pm corresponding to ( a ) P. M. A. Sherwood and J. J. Turner J . Chem. SOC. ( A ) 1971 2474; (b) S. T. King and J. H. Strope J . Chem. Phys. 1971,54 1289. ( a ) H. Kohler and B. Seifert 2. anorg. Chem. 1970 379 1 ; ( b ) H . Matschiner H . Kohler and R. Matuschke ibid. 1971 380 267; (c) H. Kohler B. Eichler and R. Salewski ibid. 1970 379 183; ( d ) W. Beck P . Swoboda K. Feldl and R . S. Tobias, Chem. Ber. 1971 104 533; ( e ) W. Gottardi Angew. Chem. Internat. Edn. 1971, 10 416. ( a ) J. C. B. White and S. A. Mason Actu Cryst.1970 B26 2068; ( 6 ) F. Knoll and U. Krumm Chem. Ber. 1971 104 31; (c) H. G. Viehe and Z . Janousek Angew. Chem. Internat. Edn. 1971 10 573; Z. Janousek and H. G. Viehe ibid. p. 574. + + 296 D . W . A . Sharp M . G . H . Wallbridge and J . H. Holloway single and triple bonds respectively.6 Base-catalysed addition of hydrogen cyanide to cyanogen gives di-iminosuccinonitrile (39) which is readily reduced to diaminomaleonitrile (40). Di-iminosuccinonitrile is extremely reactive ; nucleo-philes displace the nitrile groups it undergoes cycloaddition with electron-rich olefins and forms heterocycles e.g. by condensation \ /NH2 HN CN H*N \ \ / CN /c=c\ NC NC with SCI to give (41). The NC NC addition of cyanide ion (from KCN) to cyanogen gives the heterocyclic salt KC,N (42).," s-Triazine forms adducts with Lewis acids presumably by co-ordination through the nitrogen.Hydrogen halides normally form s-triazinium CN (42) salts but at least in the presence of hydrogen iodide ring-opening is postulated and ionic species such as [I,CHN=CHNHCH=NH,]+I- are formed.7b Cyanogen isocyanate NCNCO is conveniently prepared by heating silver isocyanate ;'" chlorine isocyanate is planar with a weakly bent NCO group," alkali fluorides catalyse its polymerization and also the production of fluoro-phosgene by intermediate formation of FNCO." Silver isocyanate reacts with trichloromethylthiosulphenyl chloride to form Cl,CSSNCO which is hydrolysed to the urea derivative (Cl,CSSNH),CO. The isocyanate adds alcohols to form carbamates e.g.Cl,CSSNHC0,Me.8d Metal cyanurates M,C,N,O undergo thermal decomposition to cyanates carbonates cyanamides and cyanides ; the actual isolated product depends upon the metal.'= Chlorofluorothiophosgene C(S)FCl reacts with metal thiocyanates to give fluorothiocarbonylisothiocyanate FC(S)NCS which depending upon the reaction conditions can be chlorinated to FCIC(SCI)NCS FCl,CNCS or FCI,CN=CCI . Further reactions of these compounds have also been described. FC1,CNCS is fluorinated by antimony trifluoride to F,CICNCS and F,CNCS and chlorinated by AIC1 to C1,CNCS. FClC(SC1)NCS cyclizes to dithiazole derivatives on heating ; these can be chlorinated to Cl,CN=CCl, ' U. Miiller and H. Barnighausen Acra Crysf. 1970 B26 1671. ' (a) R. W. Begland A . Cairncross D .S. Donald D . R. Hartter W. A. Sheppard and 0. W. Webster J . Amer. Chem. Soc. 1971 93 4953; ( 6 ) E. Allenstein V. Beyl and K. Lohmar Z. anorg. Chem. 1971 381,40. ( a ) W. Gottardi Monatsh. 1971,102 264; (6) H. H . Eysel and E. Nachbaur Z. anorg. Chem. 1971 381 71 ; (c) W. Gottardi Monatsh. 1971 102 127; (d) H. Bayreuther and A. Haas Chem. Ber. 1971,104,2588; ( e ) T. N. Roginskaya and A . I . Finkel'shtein, Russ. J. Inorg. Chem. 1971 16 333 The Typical Elements 297 ClC(O)N=CCl, F,ClCN=C(SCl)Cl and F,ClCN=CCl, whereas F,CNCS is chlorinated to F,CN=C(SCl)Cl and F,CN=CCl,. In each reaction chlorina-tion can ultimately remove the sulphur from the RNCS group.g Although they have similar energies the lowest excited states of CO (a311; v' = 0; E = 48 474 cm-') and N (A3C,' ; v' = 0; E = 49 757 cm-') have very different reactivities the carbon monoxide excited state being much more reactive."" CO which is formed from O('0) and CO and is an intermediate in many reactions probably has a three-membered ring structure with an 0-C-0 angle of 65'.Iob The solubility of water in compressed carbon dioxide indicates that hydration takes place in the gas phase probably to form carbonic acid."" Vacuum-u.v.photolysis of water in a carbon monoxide matrix produces species HCO H,CO HCOOH CO and cis- and trans- forms of HO-C=O ; ' I b the species (HCO,),- Co,,- and HCO are formed when single crystals of KHCO undergo y-irradiation. '' Free monothioformic acid HCOSH is formed on treatment of a metal monothioformate with hydrochloric acid and can be distilled at 268 K ; the most stable structure is the thiol form.Mixed seleno-thiocarbonates have now been described. Carbon disulphide reacts with barium selenide in aqueous solution to give BaCS,Se and carbon diselenide reacts with barium sulphide to give mixed crystals of BaCSSe and BaCSe . The free acid H,CS,Se has the structure SC(SH)(SeH);'2b methylation of these and related ions occurs readily with methyl iodide and (MeS),CS MeSC(S)SeMe and SC(SeMe) are found as mixtures of various conformers.'2c One of the most interesting developments in carbonate chemistry for many years has been the isolation of difluorodioxocarbonates M,CO,F (M = Cs and Me,N) from the action of carbon dioxide on caesium fluoride in acetonitrile. There is some evidence that monofluorodioxocarbonates MC0,F are formed under high pressures of CO .12d Strong acids such as HClO react with trifluoroacetic anhydride to give mixed anhydrides e.g. CF,COClO,.' Trifluoromethylhydroperoxide CF,OOH, which has previously been difficult to prepare may be obtained in good yield by decomposition of the perhydrate of hexafluoroacetone' 3b or by a modification of the original method of preparation the hydrolysis of CF,00C(0)F.'3C It behaves as a weak protic acid and forms peroxides e.g. CF,C(O)OOCF,, ' G . Dahms A. Haas and W. Klug Chem. Ber. 1971,104,2732. l o ( a ) G . W. Taylor and D. W. Setser J . Amer. Chem. SOC. 1971 93 4930; ( b ) P. R. Jones and H. Taube J. Phys. Chem. 1971,75 2991 ; M. E. Jacox and D. E. Milligan, J. Chem. Phys. 1971,54 919.l 1 ( a ) C. R. Coan and A. D. King jun. J . Amer. Chem. SOC. 1971 93 1857; ( b ) D. E. Milligan and M. E. Jacox J . Chem. Phys. 1971 54 927; (c) R. W. Holmberg ibid., p. 1730. l 2 ( a ) G. Gattow and R. Engler Angew. Chem. Internat. Edn. 1971 10 415; ( 6 ) G. Gattow and M. Drager 2. anorg. Chem. 1971,384,235; (c) M. Drager and G. Gattow, Chem. Ber. 1971 104 1429; (d) E. Martineau and J. B. Milne Chem. Comm. 1971, 1327. l 3 (a) M. G. Harriss and J . B. Milne Canad. J. Chem. 1971,49 2937; ( b ) C. T. Ratcliffe, C . V. Hardin L. R. Anderson and W. B. Fox Chem. Comm. 1971 784; (c) P. A. Bernstein F. A. Hohorst and D. D. DesMarteau J . Amer. Chem. SOC. 1971 93, 3882; ( d ) C. T. Ratcliffe C. V. Hardin L. R. Anderson and W . B . F o x ibid. p . 3886 298 D.W . A . Sharp M . G . H. Wallbridge and J . H . Holloway with the appropriate reactants particularly acid fluorides ;I3' with chlorine monofluoride it forms CF300C1 the first compound containing the OOCl linkage as a stable yellow Carbon tetrahalides form solid adducts e.g. Me4NX,2CBr, Et,NX,CCl (X = C1 Br or I) with tetra-alkylammonium halides. In the solids each CX molecule is surrounded by four halide ions whereas in their solutions in inert solvents the adducts have a single halide ion bound to a face of the CX m~lecule.'~" From force constant calculations on spectroscopic data the CCl,. radical is formulated with ClCCl angles of 120".'4b Silicon.-A great deal of work continues to be done on (p + d)n-bonding involving silicon and the heavier Group IV elements.At this stage it may still be said that the results obtained differ depending upon the technique used for the study and the other atoms bonded to the Group IV element. Photoelectron spectroscopy indicates (p + @-bonding in silicon-halogen bonds and probably in germanium- and tin-halogen bonds.' 5a Many parameters derived from n.m.r. spectra may be discussed in terms of n-bonding and n-bonding has been adduced in aryl-Si aryl-Ge Si-0 Si-S Ge-S Sn-S (but not Si-N, Ge-0 or Sn-0) bonds.' 5 b However the effect of varying silicon-substituents on the (p -+ d)n interaction between the silicon and an attached aromatic system is small. ' 5c Diamagnetic studies on aryl-silicon compounds apparently refute the idea of (p + d)n-bonding in these systems'5d and no evidence for n-bonding is found from the vibrational spectra of tetravinylsilane.5e The kinetics of the acid-catalysed hydrolysis of (43) suggest that the reaction proceeds through a n-bond-stabilized siliconium species.' 'J- Both the relatively high stability of the Ph3Si+ cation in a mass spectrometer'5g and evidence on S i - C bond lengths'5h favour d-orbital interaction. l 4 ( a ) J. A. Creighton and K. M. Thomas J . Mol. Struct. 1971 7 173; (b) R. Steudel, Z . Naturforsch. 1971 26b 475. l 5 ( a ) S. Cradock and E. A. V. Ebsworth Chem. Comm. 1971 57; P. J. Bassett and D. R. Lloyd J . Chem. SOC. ( A ) 1971 641; D . C. Frost F. G. Herring A. Katrib, R. A. N. McLean J. E. Drake and N. P. C. Westwood Chem. Phys. Letters 1971, 10 347; (6) R. E. Hess C. K. Haas B. A. Kaduk C.D. Schaeffer jun. and C. H. Yoder Inorg. Chim. Acta 1971,5 161 ; C. H. Yoder and R. Schenck J . Inorg. Nuclear Chem. 1971 33 2699; M. E. Freeburger and L. Spialter J . Amer. Chem. Soc. 1971, 93 1894; C. H. Yoder Inorg. Nuclear Chem. Letters 1971,7,637; ( c ) R . H. Cox and W. K. Austin jun. J . Organometallic Chem. 1971 26 331 ; ( d ) R. L. Mital and R. R. Gupta Inorg. Chim. Acta Rev. 1970 4 97; ( e ) G. Davidson Spectrochim. Acta, 1971 27A 1161 ; (f) R. E. Timms J . Chem. SOC. ( A ) 1971 1969; ( g ) J. M. Gaidis, P. R. Briggs and T. W. Shannon J . Phys. Chem. 1971,75 974; (h) B. Beagley J. J. Monaghan and T. G. Hewitt J. Mol. Struct. 1971 8 401 The Typical Elements 299 Free silicon and germanium atoms have been generated from silane or germane in a microwave-sustained helium plasma and detected by spectroscopic means.Silicon atoms react with silane to produce disilane; the mere existence of silicon atoms is of importance in understanding the mechanism of silane decomposi-tions.’ 6a The general aspects of silicon radical chemistry have been reviewed. 16’ Comparison of the e.s.r. spectra of AlH - SiH, and PH + radicals shows that the ratio of 3 p to 3s orbitals increases markedly from aluminium to phosphorus, an increase which suggests a tendency for the radicals to flatten in this order. The tendency is even greater for the alkyl derivatives the aluminium radicals being flattened but the phosphorus radicals being bent. Condensation reactions of silylamines are strongly catalysed by pentaborane(9). N(SiH,) gives (SiH,),-NSiH,N(SiH3) and (SiH,),NMe gives SiH,(Me)NSiH,N(Me)SiH ; silane is also produced in each case.HBr reacts with both condensed derivatives to cleave all Si-N bonds. 18’ Trisilyl- or trigermyl-arsine reacts with chlorodi-methylarsine to give (H,SiAs) and (H,GeAs) respectively examples of metalloid-substituted polyarsines. 8b The products of the reactions of lithium tetrahydroaluminate with alcohols, thiols and metal alkoxides react with silyl bromide to give alkyl silyl ethers and sulphides ;’ 9a the previously unknown compounds (MeCO,) SiH and (CF,CO,),-SiH are prepared by reacting C1,SiH with sodium acetate and trifluoroacetic anhydride respectively. 19b By treatment of silanes with elemental bromine and chlorine at low temperatures limited and controlled substitution of SiH by Six may be effected without major cleavage of Si-Si bonds.20u Tin(rv) chloride also has been shown to be a specific chlorinating agent for silanes and germanes: Si-Si and Ge-Ge bonds are not cleaved and there is only monosubstitution to e.g.(SiH,Cl),SiH at each metalloid atom.20b Halogeno-disilanes and -trisilanes may also be formed by the action of a silent electric discharge on halogeno-monosilanes.20c The synthetically important chemistry of trichlorosilane-tertiary amine adducts has been summ+arized;20d the 1 1 adduct between HSiC1 and Me,N is formulated as Me,NH SiCl - . 2 0 e Si-Fluorocarbosilanes, e.g. (F,Si),CH, have been prepared by fluorination of an Sic1 group in a com-pound with CH bridges using zinc fluoride. Perchlorinated carbosilanes undergo some decomposition during fluorination but in some cases are completely l 6 ( a ) P.P. Gaspar K . Y. Choo E. Y. Y. Lam and A. P. Wolf Chem. Comm. 1971, 1012; ( b ) I . M. T . Davidson Quart. Rev. 1971 25 1 1 1. A. Begum A. R. Lyons and M. C. R. Symons J . Chem. Soc. ( A ) 1971,2290. ( a ) W. M. Scantlin and A. D . Norman Chem. Comm. 1971 1246; (b) J. W. Anderson and J. E. Drake ibid. p. 1372. l 9 ( a ) C. Glidewell J . Chem. Soc. ( A ) 1971 823; J . W. Anderson and J. E. Drake Inorg. Nuclear Chem. Letters 1971 7 1007; (b) E. Hengge and E. Starz Monatsh. 1971, 102 741. * O (a) F. Feher P. Plichta and R. Guillery Inorg. Chem. 1971,10,606; ( b ) J. E. Bentham, S. Cradock and E. A. V. Ebsworth Inorg. Nuclear Chem. Letters 1971 7 1077; ( c ) J .E. Drake and N. P. C. Westwood J . Chem. Soc. ( A ) 1971 3300; J. E. Drake, N. Goddard and N. P. C. Westwood ibid. p. 3305; ( d ) R. A. Benkeser Accounts Chem. Res. 1971,4,94; ( e ) M. A. Ring R. L. Jenkins R. Zanganeh and H. C. Brown, J . Amer. Chem. SOC. 1971 93 265 300 D . W . A . Sharp M . G . H. Wallbridge and J . H . Holloway unreactive.21a Carbosilanes containing S i x 1 bonds e.g. (Cl,Si),CH2 are reduced to silanes e.g. (H,Si),CH, by LiAlH whereas reduction of compounds containing C - C l bonds leads to S1-C bond cleavage in addition to the formation of Si-H and C-H bonds.21b Photochlorination of carbosilanes gives per-chloro-derivatives e.g. (C13SiCH2),SiC12 -+ (Cl3SiCCl2),SiC1, whereas sulphuryl chloride in the presence of benzoyl peroxide gives partially chlorinated products e.g.(Cl SiCHCl),SiCl . The SiH groups of carbosilanes can be used for controlled reduction of perchlorocarbosilanes,2 lC e.g. (C13SiCCl,),SiC12 + (H,Si),CH -+ Cl,SiCHCI~SiCl2CC1,-SiCl3 Methylation of cyclic perchlorocarbosilanes by MeMgCl is generally of the silicon but ring rearrangements occur e.g. (44) gives (45).2 I d Si-Fluorosilanes are methylated at silicon by LiMe whereas perchlorosilanes are attacked at the carbon.21e H* ~ e ~ i ' ' S i ~ e , \ I ,c=c \ :;2 C H2C' 'CCI, I. I C12Si ,SiCl, C Me SiMe, C1Z (44) (45) + Methylsilanes give methylpolysilanes under the action of a silent-electric discharge,,," e.g. MeSiH -+ MeSiH,-SiH,Me the intermediates in the reactions are probably similar to these present in pyrolysis photolysis,22b and platinum-salt-catalysed disproportionationst2' of methylsilanes.A silent electric discharge on a silane in the presence of GeH,, PH, or ASH gives a methylsilylmetalloid derivative e.g. MeSiH,GeH, Dimethylchlorosilane Me,SiHCl has proved difficult to prepare pure but may be obtained so by photolysis of polydimethylsilanes in the presence of hydrogen chloride ;22d its homologues R,SiHCl are formed by reacting a sterically 2 1 ( a ) G . Fritz and M. Berndt Angew. Chem. Internat. Edn. 1971 10 510; ( b ) G . Fritz and H. Frohlich Z . anorg. Chem. 1971 382 9 ; ( c ) ibid. p. 217; ( d ) G. Fritz P. Bottinger and B. Braunagel Z . Naturforsch. 1971,26b 478; (e) G. Fritz R. Riekens, T. Giinther and M. Berndt ibid. p. 480. '' ( a ) J . W.Anderson and J. E. Drake J . Chem. Soc. ( A ) 1971 1424; ( b ) I. M. T. Davidson and C. A. Lambert ibid. p. 882; R. M. Baird M. D. Sefcik and M. A. Ring Inorg. Chem. 1971 10 883; M. Ishikawa and M. Kumada Chem. Comm., 1971 489; ( c ) K. Yamamoto H. Okinoshima and M . Kurnada J . Organomefallic Chem. 1971 27 C31; ( d ) M. Ishikawa and M. Kumada Chem. Comm. 1971 507; ( e ) F. Metras J.-C. Lahournere and J. Valade J . Organometallic Chern. 1971 29, 41; (f) P. Gerval R. Calas E. Frainnet and J. Dunogues ibid. 1971 31 329; (g) M. B. Lacout-Loustalet J . P. Dupin F. Metras and J. Valade ibid. p. 187 The Typical Elements 30 1 hindered Grignard reagent with silicon tetrachloride.”‘ Trichlorosilanes are formed by reducing hexa-alkyldisilanes with ketones in (Me,N),PO in the presence of catalytic amounts of sodium sodium amide or sodium hydride ;22p alkylhalogeno- or alkylmethoxy-silanes are also reduced to alkylsilanes by Grignard Attempts have been made to isolate siliconium ions (analogous to carbonium ions) but so far there has been no evidence for these species in solution.Me,SiF, Me,SiF, and MeSiF interact with SbF in SbF,-SO (or S0,ClF) solution but in each case the best description of the interaction appears to be that of fluorine-bridging to SbF,.23a In the light of new evidence previous reports that halide exchange at silicon proceeds through a siliconium ion pair appear to be erroneous23b and racemization of chlorosilanes proceeds through six-co-ordinate derivative^.'^' In the area of anion chemistry the n.m.r. spectra of Group IV triphenyl-lithium compounds depend more upon the degree of association between the lithium cation and anion than on any other fa~tor.’~‘ Bis(trimethylsilyl)diazomethane (Me,Si),CNN has been fully characterized from the lithiation of trimethylsilyldiazomethane followed by reaction with trimethylchlorosilane.It is thermally stable but undergoes many reactions of organic interest.24b A terminal alkyl hydrogen can be substituted by a tri-methylsilyl group e.g. CH,=CHCH,SiMe -+ Me,SiCH=CHCH,SiMe, by the action of trimethylchlorosilane and magnesium in (Me,N),PO in the presence of catalytic quantities of TiC1 or FeCl Carbene insertion reactions into Group IV hydrides and halides have been summarized;25b in addition to insertion into Si-H and C-H bonds of organosilanes silacyclobutanes [e.g.(46)] undergo ring expansion to silacyclopentanes [e.g. (47)]’ 5 c and the reactions c1 c1 PhHgCCI,Br Me,Si of organosilicon hydrides with organozincs and methylene iodide are believed to involve a carbene insertion into a Si-H bond.25d ’’ (a) G. A. Olah and Y. K. Mo J. Amer. Chem. SOC. 1971,93,4942; (b) L. H. Sommer, G. D . Homer A. W. Messing J. L. Kutschinski F. 0. Stark and K. W. Michael, ibid. p. 2093; ( c ) R. J. P. Corriu and M. Leard Chem. Comm. 1971 1086. 2 4 (a) R. H. Cox E. G. Janzen and W. B. Harrison J. Magnetic Res. 1971 4 274; (b) D. Seyferth and T. C. Flood J. Organometallic Chem. 1971 29 C25. 2 5 (a) J . Dunogues R. Calas N. Ardoin C. Biran and P. Lapouyade J . Organometallic Chem. 1971,32 C31; ( 6 ) D .Seyferth Pure Appl. Chem. 1970,23,391; ( c ) D. Seyferth, R. Damrauer S. B. Andrews and S. S. Washburne J. Amer. Chem. SOC. 1971 93, 3709; (d) J . Nishimura J. Furukawa and N. Kawabata J. Organometaflic Chem., 1971,29,237; ( e ) F. R. Jensen and D. D. Davis J. Amer. Chem. SOC. 1971,93,4047; (f) A. G. Brook J. M. Duff and D . G. Anderson ibid. 1970,92,7567; ( g ) J. P. Picard, R . Calas J. Dunogues and N. Duffaut J. Organometaflic Chem. 1971 26 183 302 D. W . A . Sharp M. G . H. Wallbridge and J . H. Holloway A general procedure for the formation of optically active organo-derivatives of Group IV elements involves interaction of Group IV organometallic anions with optically active alkyl halides ; the reaction apparently always goes with retention of configuration ;25e optically active silyl- and germyl-methyl-lithium reagents have also been described and used to follow the stereochemistry of carbene insertion reactions.25f The Me,SiCl-Mg-(Me,N),PO system reacts with methylbenzoate to give the 0- and C-silylated mixed ketal PhC(SiMe,)-(OMe)(OSiMe,) which reacts with base to give PhC(Me)(OMe)SiMe,OSiMe .,'g Silicon difluoride reacts with trifluoropropyne to FX /H I.I (48) c=c F2 Si - SiF, Si-Si bond consistent with the formation of give (48) which contains an an intermediate .SiF2.SiF,. diradical.26 General cleavage reactions of the Si-C bond have been reviewed ;27a the lithium but not the sodium derivatives LiC6H,SER (E = Si or Ge) re-arrange in ether solution to R,EC6H,SLi derivatives which are useful for the preparation of silyl- and germyl-thiol~.~~~ The detailed crystal structure of tetraphenylsilane shows as in other phenylsilanes and aryl transition-metal derivatives a distortion of the aryl ring the internal angle at C-1 being 116.1", this being compensated by a widening of the angles at C-2 and C-6.27c Good bond-energy data are now available on compounds of the types Me,M and Me3M-M'Me,28" and the trends are much as expected without invoking n-bonding ; Si-Si bond strengths are dependent upon substituents.28b The formation of perarylated cyclosilanes and cyclogermanes from diary1 dihalides and Li Na or Na-naphthalene and their degradation in a mass spectrometer proceed through stepwise addition or elimination of Ar,Si units.28c The products of the cleavage of metal-metal bonds in Me,M-M'Me have been discussed in terms of the predictions of hard and soft acid and base theory and bond polari-ties.28d The thermal data now available should be applied to these reactions.The [Me,N(H)SiMe,]+ cation is formed in reactions of HCo(PF,) or HCo(CO) with Me,SiNMe or of Me,SiCo(CO) with Me,NH.29 When Me,SiPh and Me,Si(benzyl) undergo ammonolysis in ammonia in the presence of potassium amide the phenyl and benzyl groups are removed and the product is H,N.SiMe,-NH.SiMe,.NHK ; this reacts with the acid ammonium 2 6 C. S. Liu and J. C. Thompson Znorg. Chem. 1971 10 1100. ' (a) V. Chvalovsky Organometallic Reactions 1972 3 in press ; (6) A. R. Bassindale and D. R. M. Walton J. Organornetallic Chem. 1970 25 389; (c) C. Glidewell and G.M. Sheldrick J. Chem. Soc. ( A ) 1971 3127. (a) M. F. Lappert J. B. Pedley J. Simpson and T. R. Spalding J. Organometallic Chem. 1971 29 195; D. Quane J. Phys. Chem. 1971 75 2480; (b) E. Hengge, Monatsh. 1971 102 734; (c) W. P. Neumann Pure Appl. Chem. 1970 23 433; (d) C. F. Shaw and A. L. Allred Inorg. Chem. 1971,10 1340. 2 9 R. E. Highsmith J. R. Bergerud and A. G. MacDiarmid Chem. Comm. 1971 48 The Typical Elements 303 chloride to give cyclosilazanes.30 Trimethylsilyl derivatives of phosphoramidic acids e.g. OP[N(H)SiMe,] are formed by trans-silylation involving hexa-methyldisilazane ; la silylated sulphoximes containing Si-halogen bonds are also formed by trans-silylation on heating they give bis(sulphoximino)silanes, e.g. [Me,S(O)N],SiR . lb The reactions leading to silazanes are now well established.Me,Si[NPMe,] reacts with X,SiMe to give (49) containing a (49) dipositive cation.,," Conventional methods involving reactions of N-X with Si-Cl have led to the preparations of ClSiMe,.NMe.SiMe,.NMe-SiMe,-NR,, Me,Si-NR-SiMe,.NMe.SiMe,.NRSiMe, Me,Si.NR.SiMe,.NMe.SiMe,-NMe-SiMe,.NR.SiMe, Me,Si(NMe-SiMe,.NRR ') 3 3 b 9 c dodecamethyl-(50) decame-thyl-(51) and other N-methylcyclotetrasilazanes32d and nonamethylcyclotri-silazane (52). Heterocyclic ring systems SiOSiOSiNGeN SiOSiOSiNPN, SiOSiNBN,32" SiNSiNSiNSiP"',32" SiNSiNP'I'N SiOSiNP'I'N SiOSiNPVN,33b SiNSiNSN,,,' SiNSiNSiNBN and SiNSiNSiNGeN 3d have been prepared by analogous reactions (the ring atoms are given in order around the ring). The reactions of cyclosilazanes with iron(u1) chloride which cleave the Si -N bonds, proceed through intermediates which are believed to contain Fe-N-Si bonds, Me H Me Me,SiO" SiMe Me,SiO" SiMe Me2Si0N\SiMe, Me2Si.N SiMe Me,Si .N SiMe, Me H I I Si Me2 (50) (51) (52) 'NMe f MeN \ \ m e MeN ,NMe f / / MeN \ W.Jansen H. Kessel and 0. Schmitz-DuMont Z . anorg. Chem. 1971 384 124. ( a ) H. H. Falius K.-P. Giesen and U. Wannagat Znorg. Nuclear Chem. Letters, 1971 7 281 ; (b) W. Wolfsberger and H. Schmidbaur J. Organometallic Chem. 1971, 28 3 17. ( a ) W. Wolfsberger and H. Schmidbaur J. Organometallic Chem. 1971 28 301; (b) L. Gerschler and U. Wannagat ibid. 1971 29 217; (c) U. Wannagat and L. Gerschler Annalen 1971 744 11 1 ; (d) U. Wannagat R. Braun L. Gerschler and H.-J.Wismar ibid. 1971 26 321 ; U. Wannagat R. Braun and L. Gerschler Z. anorg. Chem. 1971 381 168; U. Wannagat F. Rabet and H.-J. Wismar Monatsh., 1971 102 1429; ( e ) U. Wannagat and L. Gerschler Znorg. Nuclear Chem. Letters, 1971 7 285. ( a ) F. Rabet and U. Wannagat Z . anorg. Chem. 1971 384 115; ( 6 ) U. Wannagat, K. Giesen and F. Rabet ibid. 1971 382 195; (c) 0. J. Scherer and R. Wies 2. Naturforsch. 1970 25b 1486; (d) U. Wannagat and L. Gerschler Z. anorg. Chem., I97 1 383 249 304 D . W. A . Sharp M . G . H . Wallbridge and J . H. Holloway the iron being co-ordinated by a nitrogen from another part of the a d d ~ c t . ~ ~ In the reaction of silazanes with alcohols the controlling step is electrophilic attack by the alcohol at the hetero-atom whereas in silathianes the controlling step is nucleophilic attack on the silicon with primary alcohols or electrophilic attack on the hetero-atom with secondary alcohols.34b Trimethylsilylamine Me,SiNH has been characterized for the first time by ammonolysis of the dialkylaminosilane Me,SiNR .The N-protons of iso-thioureas can be trimethyl~ilylated~~' but the products have limited thermal stability and give carbodi-imides e.g. (Me,Si),NC[(O)SOSiMe,]=NSiMe -+ Me,SiNCNSiMe, N-Silylphosphinimines Me,P=NSiMe - "F result from interaction of Me3-P=NSiMe and the appropriate fluorosilane or by fluorination of the corres-ponding chlorides with sodium fluoride. The trifluoro-derivative is dimerized through bridging nitrogen^.^ 5c Perlithio-derivatives of acetonitrile are readily converted into trimethylsilyl compounds with trimethylchlorosilane.What is apparently Li,CCN reacts with Me3SiC1 to give the ynamine Me,SiC-CN(SiMe,) and the ketenimine (Me,Si),C=C=NSiMe . 3 5 d N-Silylated hydrazines are readily prepared from lithium hydrazides and chloro-silanes ; compounds such as ClSiMe,.NMe.SiClMe show hindered rotation about the N-N bond.36a Silylhydrazides are also formed by hydrosilylation of an N=N double bond,36b e.g. Ph,SiH + RN=NR + Ph,SiNRNRH (R = C0,Et) Hydrazine reacts with Group IV organo-chlorides or amines react with metal hydrazides to give hydrazines e.g. (Me,Sn) (Me Si)NN(CMe,) (GeMe,) ; all are stable except for compounds containing Me Sn groups.36c Zinc cadmium and mercury tris(trimethylsilyl)hydrazides e.g. [(Me,Si),NN(SiMe,)],Hg are formed from the lithio-derivatives and metal halides.36d Silyl- or germyl-(trimethyl-stanny1)organohydrazides are oxidized by p-benzoquinone to the di-imines RN=NEMe (E = Si or Ge) further evidence for the greater lability of the trimethylstannyl The reactions of light-blue bis(trimethylsi1yl)di-imine (bsd) have been summarized.36S It undergoes a great range of reactions many involving electron-transfer ; lithium derivatives Li(bsd) and Li(bsd) can be formed.6g Organosilicon derivatives of amino-alcohols have been reviewed.37 3 4 ( a ) N. G . Klyuchnikov F. I . Karabadzhak and V. B. Losev J . Gen. Chem. (U.S.S.R.), 1971 41 166; ( 6 ) V. 0. Reikhsfel'd and E. P. Lebedev ibid. 1970 40 2038. 3 5 (a) N. Wiberg and W . Uhlenbrock Chem. Ber. 1971 104 2643; (b) H .R. Kricheldorf, Annalen 1971 745 81; (c) W. Wolfsberger H.-H.Picke1 and H. Schmidbaur Chem. Ber. 1971 104 1830; ( d ) G . A. Gornowicz and R. West J . Amer. Chem. SOC. 1971, 93 1714. 3 6 ( a ) 0. J. Scherer and U. Bultjer Angew. Chem. Internat. Edn. 1971 10 343; ( 6 ) K.-H. Linke and H. J . Gohausen ibid. p. 408; ( c ) N. Wiberg and M . Veith Chem. Ber., 1971 104 3176; ( d ) K. Seppelt and W. Sundermeyer ibid. 1970 103 3939; ( e ) N. Wiberg and M. Veith ibid. 1971 104 3191; (f) N. Wiberg Angew. Chem. Internat. Edn. 1971 10 374; ( g ) N. Wiberg and W. C. Joo Z . Naturforsch. 1971 26b 512. 3 7 E. Lukevics L. Liberts and M. G . Voronkov Russ. Chem. Reu. 1970 39 953 The Typical Elements 305 Cyclic phosphines (53) (54) are formed from reactions between Ph,ECl com-pounds and K,PPh or KPHPh (E = Si or Ge) or the chloride and phosphine in the presence of trimethylamine although Ph,GeCl and Ph,PH in the presence of trimethylamine give only the acyclic compound Ph,GeCI-PPh.GeClPh .,' Ph Ph P / \ Ph,E EPh2 \D' Ph E/ "EPh, I t PhP ,PPh E Ph 2 (E = Si or Ge) (E = Si Ge or Sn) (53) (54) The reactions of disiloxanes with P,O have been previously described to give silylphosphates as products but it has now been shown that the metaphosphates, e.g.[Me,SiO],P(O)O[Me,SiOP(O)O],P(O) [OSiMe,] are also formed in good yield ;39a alkylphosphinic acids react with (EtO),SiR compounds to give deriva-tives containing Si,O,P cages. 9b Mixed peroxides have not been described previously but trialkylsilylamines react with triorganogermanium hydroperoxide to give R SiOOGeR compounds.40 Dimethylsilanone Me,SiO has been postulated as an intermediate formed during the pyrolysis of octamethylcyclo-tetrasiloxane ;,la it appears that the frequently quoted highly ordered structure attributed to phenylsilsesquioxane (PhSiO,,,) is wrong and that the polymer is built up from a random combination of incompletely closed cages.41b Silicon, germanium tin and lead derivatives of keto-enols compounds which should have wide synthetic application have been reviewed.,," Alkyl-trichlorosilanes react with diketones to give compounds [RSi(diket)2]+X-.42b Organogroup IV difluorodithiophosphates e.g.Me SiSP(S)F and Me,CISnSP(S)F result from the action of HPS,F2 on Me,SiX (X = H NEt, or C1) and are stable compounds, although HPS,F reduces SnCI to SnCl without formation of a difluorodithio-phosphate., Silicon difluoride does not give the expected straightforward products with alkylsilanes ; it reacts with Me,SiOMe to give Me,SiSiF prob-ably by initial formation of the insertion product Me,SiSiF,OMe ;44a silicon difluoride inserts into the C-I bond of CF,I to give CF,SiIF, which may be fluorinated to CF,SiF with antimony trifl~oride.,~' Xenon difluoride is a specific fluorinating agent for Si-Cl bonds e.g.Me,SiCl -+ Me,SiF .44c 3 * H. Schumann and H. Benda Chem. Ber. 1971 104 333. 39 (a) V. P. Mileshkevich and A. V. Karlin J . Gen. Chem. (U.S.S.R.) 1970 40 2565; (6) K . A. Andrianov T. V. Vasil'eva and T. K. Demykina ibid. p. 1552. 40 A. P. Tarabarina V.A. Yablokov and N. V. Yablokova J . Gen. Chem. (U.S.S.R.), 1970,40 1082. 4 1 ( a ) I . M. T. Davidson and J. F. Thompson Chem. Comm. 1971 251 ; (6) C. L. Frye and J. M. Klosowski J . Amer. Chem. SOC. 1971 93,4599. 4 2 ( a ) Y. I. Baukov and I . F. Lutsenko Organometallic Chem. Rev. 1970 A6 355; ( 6 ) G. Schott and K . Golz Z . anorg. Chem. 1971 83 314. 4 3 D . W. McKennon and M. Lustig Inorg. Chem. 1971 10 406. 4 4 ( a ) J. L. Margrave D. L. Williams and P. W. Wilson Inorg. Nuclear Chem. Letters, 1971 7 103; (b) K. G. Sharp and T. D. Coyle J . Fluorine Chem. 1971/2 1 249; (c) J . A. Gibson and A. F. Janzen Canad. J . Chem. 1971,49,2168 306 D . W . A . Sharp M . G . H. Wallbridge and J . H. Holloway Iminosilicates K,Si(NH) K,Si,(NH) and K,Si3(NH) are formed by ammonolysis of SiBr or SiI with potassium amide in liquid ammonia; the iodide is apparently less completely solvolysed than the br~mide.~'" Silicon tetrachloride undergoes partial ammonolysis with ammonia in diethyl ether below 21 3 K to give hexachlorodisilazane Cl,SiNHSiCl hexachlorotrisilazane (55), H ( 5 5 ) and polychlorosilazanes ; hexachlorodisilazane can be lithiated with BuLi to LiN(SiCl,) and it is apparent that these systems are very complex.45b Electron diffraction studies on the molecules Cl,SiNMe and F,SiNMe show planar 'heavy-atom' skeletons but rather unexpectedly there is little difference between the dimensions of the two molecules that may be attributed to the effect of the more electronegative Aniline forms 1 1 and 1 2 complexes with silicon tetrafl~oride.,~ A detailed structural analysis on CdSiP which has the chalcopyrite structure indicates a regular tetrahedral Sip unit in this family of The great strength of the Si-F bond is shown by the clean decomposition of CHF,CH,Si(OMe) into vinyl fluoride and fluorotrimethoxysilane, FSi(OMe),.48" The Si-0-Si angle in (Cl,Si),O is very similar to that in (H,Si),O; both are smaller than that in (F,Si),O.The Si-0-C angle in F,SiOCH is greater than that in H,SiOCH3. These results are consistent with (p 4 &-bonding from oxygen to Fluorosiloxanes have been formed by the action of thionyl fluoride on silicon difluoride. No sulphur-containing silicon derivatives are formed and the products are SiF,(SiF,),OSiF, ( n = 1 or 2)' SiF30SiF, SiF,OSiF,OSiF, and (SIOF,) (n = 2 or 3 ) ; the first and last members of the series are new corn pound^.^^ Among the structures of silicate-like materials that have been published this year that of thaumasite [Ca,Si(OH) ,12H,O](SO,)(CO,) is of interest as containing the first completely established examples of octahedral Si(OH)6 regular Si06 units are also found in the A(1V) modification of silicon diphosphate, 4 5 ( a ) S .1. Ali Z . anorg. Chem. 1970,379,68; ( b ) U. Wannagat H. Moretto P. Schmidt, and M. Schulze ibid. 1971 381 288; ( c ) W. Airey C. Glidewell A. G. Robiette, G. M. Sheldrick and J. M. Freeman J . Mol. Structure 1971 8,423. 46 A. A. Ennan and B. M. Kats Russ. J . Inorg. Chem. 1971 16 776. 4 7 S. C. Abrahams and J. L. Bernstein J . Chem. Pfiys. 1971 55 796.48 ( a ) D. Graham R. N. Haszeldine and P. J. Robinson J . Chem. Soc. (B) 1971 61 1 ; ( 6 ) W. Airey C . Glidewell A. G. Robiette and G. M. Sheldrick J . Mol. Structure, 1971 8 413. ( a ) R. A. Edge and H. F. W. Taylor Acta Cryst. 1971 B27 594; ( 6 ) F. Liebau and K.-F. Hesse Z . Krist. 1971 133 213; ( c ) E. N. Treushnikov V. V. Ilyukhin and N. V. Belov Sou. Phys. Cryst. 1971 16 56. 49 K. G. Sharp and J. L. Margrave J . Inorg. Nuclear Chem. 1971,33 2813 The Typical Elements 307 SiP,O,; the P,07 group is asymmetric with a P-0-P angle of 132".50b Hydrothermal crystallization of the CaO-SiO system in NaOH solutions gives a phase Na,Ca,(Si,O ,,) which contains a linear trisilicate gro~ping.~" Precise studies are now being made on peroxysilicates. Na,SiO ,3H,O has been fully characterized ; it liberates oxygen on standing passing through Na,SiO ,H,-0 ,2H,O to hydrates5 The properties and reactions of silicon difluoride have been ~ummarized.~' Germanium-Many mixed dihalogenogermanes e.g.GeH,ClBr have been prepared by exchange reactions or by the action of hydrogen halides or boron halides on the GeH,X derivatives; boron halides will also substitute mono-chl~rogermanes.~~" Mixed halogeno-derivatives of methylgermane are prepared ~imilarly.~ 3b Digermylselenide (H,Ge),Se has a Ge-Se4e bond angle of 94.6" ; the GeH groups are staggered with respect to the Ge-Se bonds. It is concluded that there is little n-bonding in this or related selenidesS4" a conclusion also reached for germanium-halogen bonds from electric dipole rnea~urements.~~~ Spectroscopic studies on the germyl GeH,- ion suggest a bond angle of 93" ; 5 5 a the pyramidal GeH,Cl.radical [and the germylene( :GeHCl)-see later] can be isolated in matrices after photolysis of GeH,Cl. Comparison of the radical with related Group IV species shows that carbon-containing species are planar and have appreciable z-bonding if the attached atoms have suitable size and electronic arrangements whereas there is no evidence for n-bonding in silyl-or germyl- specie^.^ 5b Some halogeno-derivatives of methylgermane have been mentioned above. They may also be prepared from the germane and AgX(C1 and Br) or iodine ; the isomeric halogenomethylgermanes are formed from diazo-methane and GeC1 or GeBr followed by reduction (GeH,CH,Cl and GeH,CH,Br) or by halogen exchange in GeH,CH,Cl with sodium iodide (GeH,CH,I).s6" Germyl fluorides are relatively unstable with respect to dis-proportionation but MeGeH,F and Me,GeHF may be prepared by fluorination of the bromide with PbF and are stable compounds although EtGeH,F pre-pared similarly is unstable.56b Ph,GeHCl undergoes a Wurtz-type reaction to Ph,GeHGeHPh with magnesium in THF ; the digermane is dearylated with HBr to dl- and meso-PhGeHBrWGeHBrPh a reaction similar to that observed with ~ i l a n e s .~ ~ 5 1 G. Rietz and H. Kopp 2. anorg. Chem. 1971 382 31; 384 19; G. Rietz and J . 5 2 J. L. Margrave and P. W. Wilson Accounts Chem. Res. 1971 4 145. 5 3 ( a ) G. K. Barker and J. E. Drake Znorg. Nuclear Chem. Letters 1971 7 39; (b) J. E. Drake R.T. Hemmings and C. Riddle J . Chem. SOC. ( A ) 1971 600. 5 4 ( a ) J. D. Murdoch D . W. H. Rankin and C. Glidewell J . Mol. Structure 1971 9, 17; (b) J. M. Bellama S. 0. Wandiga and A. A. Maryott Znorg. Nuclear Chem. Letters 1971 7 71. 5 5 ( a ) T. Birchall and I. Drummond J . Chem. SOC. ( A ) 1971 3162; (b) R. J. Isabel and W. A. Guillory J . Chem. Phys. 1971 55 1197. 5 6 ( a ) J. M. Bellama and C. J. McCormick Znorg. Nuclear Chem. Letters 1971 7 533; (b) C. H. Van Dyke J. E. Bulkowski and N. Viswanathan ibid. p. 1057. 5 7 F. Feher and P. Plichta Znorg. Chem. 1971,10 609. Loscher ibid. 1971 382 37 308 D . W. A . Sharp M . G . H . Wallbridge and J . H . Holloway The organic compounds of germanium have been the subject of a book? Hydrogermylation of phenylacetylene is catalysed by (Ph P)3 RhCl an effective hydrosilylation catalyst and cis-(Ph,P),PtCl .59a Perfluoroalkyl derivatives of germanium and tin react with Me,SnCF to give cyclopropenyl derivatives e.g.M e G e m F probably by difluorocarbene addition to the triple bond.59b A full report of the preparation of trialkylgermylalkali-metal compounds by cleavage of R,GeGeR in (Me,N),PO his now been given together with the details of their reactions as nucleophiles.60" In a rather unusual reaction the sodium salt of DMSO methylates triphenylgermane to Ph,GeMe ; Ph,GeSMe and (Ph,Ge),O are the other products.60b Chlorogermylenes ClGeX (X = C1, alkyl or Ph) are formed by decomposition of XClGe(0Me)H compounds; these germylene groups readily abstract halogen from other Group IVB deriva-tives to form XClGe(halogen) .61a Organometallic diazoalkanes Me,MC(R)N, (M = Ge or Pb; R = Me,M or CO,Et) are formed from the amino-derivatives, e.g.Me,GeNMe and Me PbN(SiMe,) and diazomethane. The ethylcarboxy-lates show some evidence for bonding from the ester of the oxygen to the metal.6 l b Dimethylgermanium dinitrate Me,Ge(ONO,) has unidentate nitrate groups as has Me,GeONO .62 A paramagnetic germanium-containing radical (56), 0 / 0 R/Ge\ R stabilized by the presence of t-butyl groups can be obtained by reaction of 2-amino-4,6-di-t-butylphenoxyl with diarylgermanium dihalides or from the diarylgermanium dihalides and the corresponding radicals containing tin or lead.63 The ethylgermatrane (57) has trigonal-bipyramidally co-ordinated germanium the Ge-N distance being 224 pm larger than covalent radii would predict but much closer than for non-bonded atoms.The germanium is dis-placed towards the ethyl group; the corresponding silicon compound has the same structure.64 5 8 M. Lesbre P. Mazerolles and J. Satge 'The Organic Compounds of Germanium,' Wiley 1971. 5 9 ( a ) R. J. P. Corriu and J. J. E. Moreau Chem. Comm. 1971 812; (b) W. R. Cullen and M. C. Waldman J . FIuorine Chem. 1971/2 1 151. 6 o ( a ) E. J. Bulten and J. G. Noltes J . Organometaffic Chem. 1971,29 397,409; (b) D. J. Sandyman and R. West ibid. 1971 30 C61. 6 1 (a) M. Massol J. Barrau and J. Satge Inorg. Nuclear Chem. Letters 1971 7 895; (b) J. Lorberth J . Organometallic Chem. 1971 27 303. 6 2 D. Potts and A. Walker Canad. J .Chem. 1971,49 202 2171. 6 3 H. B. Stegmann K. Scheffler and F. Stocker Angew. Chem. Internat. Edn. 1971, 10 499. 64 L. 0. Atovmyan Y . Y . Bleidelis A. A. Kemme and R. P. Shibaeva J . Struct. Chem., 1970 11 295 The Typical Elements 309 Germanium tetrachloride forms 1 4 complexes with phenylenediamines ; it is considered but only from spectroscopic evidence that all of the phenylene-diamines act as unidentate ligand~.~’ There has been a fair interest in the chemistry of germanates possibly because of the glass-forming properties of germanium dioxide. Only two compounds Cs20,6GeO and 4Cs20,7Ge0,, have been found in the caesium oxide-germanium dioxide system.66a K,Ge,O, has both tetrahedral GeO and trigonal-bipyramidal GeO units and is the first germanate to contain these latter species ;66b Li,Ge,O, is similar to other lithium germanates and contains GeO and octahedral GeO units.66c Single crystals obtained from a 4MgO-GeO melt have the composition Mg,,Ge,oO,, and have a structure based on close-packing of oxygens with superimposed olivine-type and MgO-type layers.66d Thiogermanates are also proving of interest and salts of the type Na,Ge,S6,14H,0 may be isolated from solution and have dimeric tetrahedral anions with two sulphur bridges.67” Discrete GeS, tetrahedra are found in Pb,GeS which has a K,SO,-type lattice;67b a more complex adamantane-like anion is found in Cs,Ge,S, ,4H20 ; each germanium has tetrahedral co-ordination the bridge Ge-S bonds (224 pm) are longer than the terminal Ge-S bonds (212 ~ m ) .~ ~ ‘ A new germanium fluoride probably (GeF,),GeF with no G e 4 e bonds is formed by reduction of the tetrafluoride with germanium ; it suggests an extensive chemistry of sub-fluorides of the Group IV elements.68 Rather like trichloro-silane trihalogenogermanes appear to form GeX - ions on treatment with amine~.~, Tin.-A simple stereochemical model based on non-bonded intramolecular Van der Waals’ interactions has been applied quite successfully to the bond angles and bond lengths in four- and five-co-ordinate tin corn pound^.^^^ It will be of interest to apply this model to other systems.A renewed interest may be expected in salt-like intermetallic compounds now that it has been shown that Na,Sn forms crystalline solvates with ethylenediamine ; physical properties of the adduct suggest an unit consisting of a trigonal prism with pyramids set on each of its square Mossbauer spectroscopy suggests that the products of the reactions between dicyclopentadienyltin(~~) and phenylmagnesium 6 5 E.M. Belousova and I. I. Seifullina Russ. J . Inorg. Chem. 1971 16 80. 6 6 ( a ) M. K. Murthy and L. Angelone J . Amer. Ceram. SOC. 1971 54 173; (b) E. Fay, H. Vollenkle and A. Wittmann Naturwiss. 1971 58 455; ( c ) H. Vollenkle A. Wittmann and H. Nowotny Monatsh. 1971 102 361 ; ( d ) R. B. Von Dreele P. W. Bless E. Kostiner and R. E. Hughes J . Solid State Chem. 1970 2 612. 6 7 ( a ) B. Krebs S . Pohl and W. Schiwy Angew. Chem. Internat. Edn. 1970 9 897; (6) K. Susa and H. Steinfink J . Solid State Chem. 1971,3,75 ; (c) B. Krebs and S.Pohl, Z . Naturforsch. 1971 26b 853. 6 8 G. P. Adams J. L. Margrave and P. W. Wilson J . Inorg. Nuclear Chem. 1971 33, 1301. 69 T. K. Gar E. M. Berliner A. V. Kisin and V. F. Mironov J . Gen. Chern. (U.S.S.R.), 1970,40 2595. 7 0 R. F. Zahrobsky J . Amer. Chem. Soc. 1971,93 3313. 7 1 ( a ) D . Kummer and L. Diehl Angew. Chem. Internat. Edn. 1970 9 895; (b) P. G . Harrison J . J. Zuckerman and J . G. Noltes J . Organometallic Chem. 1971 31 C23 310 D . W . A . Sharp M . G . H . Wallbridge and J . H. Holloway orphenylzinc halides contain metal-metal bonds e.g. (58). I b Stannane dissolves7 2a in strong aqueous acids or anhydrous fluorosulphuric acid at low temperatures to liberate one equivalent of hydrogen and to form the stannonium ion SnH,'. Br / \ Ph(C5H5)2Sn-Mg Mg-Sn(C5H5),Ph \ / Br (58) Stannyl halides SnH,X (X = C1 Br or I) are formed by the action of the hydrogen halide on stannane again at low temperatures.72b The application of 119"'Sn Mossbauer spectroscopy to the study of organotin compounds has been again reviewed73a and a new book has been published on organotin chemistry.73b The structures of the (4-halogeno-l,2,3,4-tetraphenyl-cis,cis-buta-1,3-dienyl)-dimethylphenyltin compounds (59) have been examined and show no Sn - - .X intramolecular bonding as may be present in the 4-bromo-bromodimethyltin Ph Ph Ph f i Ph Ph-Sn X / / Me Me (X = C1 or Br) (59) derivative ; rotational barriers in the former compound are steric in origin.74 Formation of free radicals from organotin compounds is common ;28c the radical resulting from the addition of trimethylstannane to buta-1,3-diene has been shown by e.s.r.spectroscopy to be (60).750 The kinetics of reaction of organotin derivatives continue to be widely studied but consistent mechanisms are not yet available. There is a rapid inversion of the asymmetric centre in l 2 ( a ) J. R . Webster and W. L. Jolly Inorg. Chem. 1971 10 877; (b) J. R. Webster, M. M. Millard and W. L. Jolly ibid. p. 879; J. M. Bellama and R. A. Gsell Inorg. Nuclear Chem. Letters I97 1 7 365. " ( a ) J. J. Zuckerman Ado. Organometallic Chem. 1970 9. 22; (b) 'Organotin Com-pounds' ed. A. K. Sawyer Dekker New vork 1971. 7 4 F. P. Boer F. B. Van Remoortere P. P. North and G. N . Reeke Inorg. Chem., 1971,10 529 cf. F. P. Boer G. A.Doorakian H. H. Freedman and S. V. McKinley, J . Amer. Chem. SOC. 1970 92 1225. 7 5 ( a ) T. Kawamura and J. K. Kochi J . Organometallic Chem. 1971 30 C8; (6) D. V. Stynes and A. L. Allred J . Amer. Chem. SOC. 1971 93 2666; (c) F. R. Jensen and D. D. Davis ibid. p. 4048; (d) K. Sisido K. Ban T. Isida and S. Kozima J . Organo-metallic Chem. 1971 29 C7; ( e ) C. W. Fong and W. Kitching J . Amer. Chem. SOC., 1971,93 3791 The Typical Elements 31 1 trialkyltin halides and halogen exchange probably proceeds through a five-co-ordinate halogen-bridged intermediate.7 5 b Thxarbon cleavage by bromine appears definitely to occur with inversion of c~nfiguration'~' although there is some evidence that tertiary substituted derivatives may behave differently from secondary.75d The insertion of sulphur dioxide into S n - C bonds appears to be an electrophilic sulphidestannylation.5e The structures of two methyltin dicyanamides have been established ; both have planar N(CN) groups and the CNSn angles are near to 180". Me,Sn[N(CN),], has an infinite two-dimensional network with trans-methyls and octahedral tin ; Me SnN(CN) has infinite chains with planar SnMe groups the co-ordination number being made up to five by axial dicyanamide groups.76 Bis(trialky1- tin and -germanium)carbodi-imides e.g. (Et SnN),C are formed from the stannoxane or germoxane and cyanamide.77 Bis(dimethylisothiocyanatotin)oxide (Me,-SnNCS)20 is dimeric with a central planar Sn,O ring. The isothiocyanate group co-ordinates through nitrogen to exocylic tin atoms and there is weak Sn-S interaction between dimers to make up the tin co-ordination to distorted ~ c t a h e d r a l .~ ~ The complexity of this structure underlines the difficulty of making accurate decisions on structure from spectroscopic measurements. Organotin azides add to thiocyanates RNCS to give (61).79a The isocyanate R-N- C= S I N- SnR: I N* / N (61) group in Me,SnNCO is believed to bridge planar SnMe groups but other isocyanates are monomeric.79b Tin derivatives of methylaminodihalogeno-phosphine sulphide Me,SnNMeP(S)X (X = F or FC1) are formed when stannylamines (Me,Sn),NMe react with the appropriate thiophosphoryl halide.80 Adducts between organotin isothiocyanates and various ligands have been reported and structures suggested on the basis of spectroscopy; the tin isothiocyanates are much better acceptors for 2,2'-bipyridyl than are the cor-responding chlorides.8 l a Adducts reported include 1 1 complexes between Ph,SnNCS and both unidentate and bidentate ligands; 1 1 and 1 2 complexes of Ph,Sn(NCS) (all 0-donor ligands);8'b 1 1 and 1 2 complexes between " Y .M. Chow Inorg. Chem. 1971 10 1938. 7 7 V. F. Gerega Y. I. Dergunov A. V. Pavlycheva Y . I . Mushkin and Y. A. Aleksandrov, J . Gen. Chem. (U.S.S.R.) 1970 40 1099; I. A. Vostokov and Y . I. Dergunov ibid., p. 1656. 7 a Y . M. Chow Inorg. Chem. 1971 10 673. 7 9 (a) P. Dunn and D. Oldfield Austral. J . Chem. 1971 24 645; ( b ) K. L. Leung and R. H. Herber Inorg. Chem. 1971 10 1020. H. W. Roesky and H. Wiezer Chem. Ber. 1971 104 2258.*' ( a ) J. L. Wardell J . Chem. SOC. ( A ) 1971 2628; (b) J. H. Holloway G. P. McQuillan, and D. S. Ross ibid. p. 1935; (c) B. A. Goodman N. N. Greenwood K. L. Jaura, and K. K. Sharma ibid. p. 1865; ( d ) P. J. Smith and D. Dodd J . Organometallic Chem. 1971 32 195; R. Barbieri R. Cefalh S. C. Chandra and R. H. Herber ibid., p. 97; (e) D. V. Naik and C. Curran Inorg. Chem. 1971 10 1017 312 D. W. A . Sharp M . G . H . Wallbridge and J . H. Holloway organotin halides and N-donor ligands (the complexes of Ph3SnC1 are assigned a trigonal-bipyramidal configuration about the tin with a planar SnC group ; the morpholine adducts of Ph2SnCl and Pr;SnCl have cis-organogroups whereas other diorganotin adducts have a trans-configuration) ;81c 1 1 complexes of organotin halides with the potentially quadridentate Schiff base bis(acety1-acetone)ethylenedi-imine (the complexes are assigned a trans-R,SnX con-figuration) ;8 I d and dialkyltin picolinates (trans-CSnC in most derivatives).8 le Trimethylstannylphosphine Me,SnPH may be prepared from LiAl(PH,), and Me3SnC1 ;82a organotin diphenylphosphides have also been reported.82b Trimethylstannylarsine may be prepared similarly but it (Me,Sn),AsH and (Me Sn),As are better prepared from potassium arsenides.82c Whereas the hydrolysis of R,SnCl (R = Bu" or Bus) gives the stannoxanes ClBu,SnOSnBu,Cl the t-butyl derivative normally gives the hydroxychloride, BuiSn(OH)Cl but under strongly basic conditions gives the oxide BuiSnO ;83a spectroscopic properties of the stannoxanes XBu,SnOSnBu,X are consistent with a central Sn,O ring with further co-ordination to an exocyclic Sn similar to that described above for the i s ~ t h i o c y a n a t e .~ ~ ~ Dialkyltin oxides react generally with organometallic halides (Hg T1 Si Ge and Pb) or carboxylates to give stannoxanes e.g. PhHgCl + BuzSnO -+ PhHgOSnBu,Cl The reactions with organotin halides have been described previ~usly.~~' Some cyclic organotin peroxides (62) with much greater hydrolytic stability than normal peroxides have been synthesized from Bu,SnO and dihydroper~xides.~~ Me,C-(CH,),-CMe, I I 0 0 I I 0 0 I I Bu,Sn ,o/ S r . 3 ~ ~ (62) Very many organotin derivatives of oxyacids have been described but once again structural evidence is mainly spectroscopic. Trimethyltin borate Me,SnBO , is formed from silver metaborate and trimethyltin bromide there are no indica-tions as to the structure.8 Di-p-acetato-bis(dipheny1tin) has bridging acetate groups and a tin-tin bond; the bridging is similar to that found in other bridged 8 2 ( a ) A.D. Norman J . Organometallic Chem. 1971,28,81; (b) H. Noth 2. Naturforsch., 1971 26b 497; (c) J. W. Anderson and J. E. Drake Canad. J . Chem. 1971,49 2524. 8 3 ( a ) C. K. Chu and J . D . Murray J . Chem. SOC. ( A ) 1971 360; (6) A. G. Davies L. Smith P. J. Smith and W. McFarlane J . Organometallic Chem. 1971 29 245; (c) A. G. Davies and P. G. Harrison J . Chem. SOC. (0 1971 1769. G. S. Akimovaand M. P. Grinblat J . Gen. Chem. (U.S.S.R.) 1971 41,480. K. Dey Z . anorg. Chem. 1971,383 338. 8 The Typical Elements 313 acetates86a and other carboxylates of ditin systems probably have similar structures.' 66 Triorganotin carboxylates react with diorganotin dichlorides to give successively the chloride-carboxylate and the dicarboxylate ; this is an alternative method for the preparation of the chloride carboxylates from the use of acids on the triorganotin chlorides.86' From spectroscopic studies trialkyltin halogenoacetates are monomeric with unidentate carboxylates in solution although there may be an increase in co-ordination number in solution ;86d the triphenyltin halogenoacetates and triorganotin oxalates are considered to be five-co-ordinate polymers in the solid state.86eJ Solutions of organotin species in acetic acid contain many complex species86g such as (EtSn),,Ac(OH), , (Et Sn) I ,Ac( OH) 92 + (Et Sn) Ac( OH), (Et Sn) Ac( OH) (Et Sn),Ac,( OH), + , and (EtSn),Ac,(OH),+.Organotin derivatives with potential donor sites on the side-chain e.g. PhMe,SnCH,CH,CHMeOH show evidence for intramolecular complexing.* '" There has been some doubt as to the configurations about tin in diphenyltin acetylacetonates but further study indicates that Ph,Sn(acac) has cis-phenyl groups with octahedral tin.' 76 In contrast to the organogermanium nitrates, MeSn(NO,) has bidentate nitrates such that the co-ordination about the tin atom is approximately pentagonal-bipyramidal Me,Sn(SO,F) has linear MeSnMe groups each tin is six-co-ordinate with bridging fluorosulphates.'" Organotin sulphonates have been prepared by acid solvolysis of Me,Sn (Me,SnSO,X ; X = F or Me),,," and sulphinates by treating organotin halides with sodium organos~lphinates~~~ and also by sulphur dioxide insertion into S n 4 bonds.89c Tetra-alkyltins react with aqueous sulphur dioxide to give sulphites R SnSO :89d from spectroscopic studies the above compounds are considered to have polymeric structures containing five- or six-co-ordinate tin (see also ref.89e). Various complexes between organotin halides and oxygen-donors have been reported. DMF forms 2 1 complexes with R,SnX compounds ; the bonding from the DMF to tin is through oxygen and when R = aryl these compounds are formed with cis-aryls and cis-chl~rides.~~" 1 1 and 1 2 com-'' ( a ) G. Bandoli D. A. Clernente and C. Panattoni Chern. Comm. 1971 31 1 ; (6) M . Delmas J .C. Maire Y. Richard G. Plazzogna V. Peruzzo and G. Tagliavini J . Organometallic Chem. 1971 30 C101; (c) A. D. Cohen and C. R. Dillard ibid., 1970 25,421 ; cf. Ann. Reports ( A ) 1970,67,297; (6) N . W. G. Debye D. E. Fenton, S. E. Ulrich and J . J . Zuckerman J . Organomerallic Chem. 1971 28 339; ( e ) B. F. E. Ford and J . R . Sams. ;bid. 1971 31 47; ( 1 ) V. Peruzzo G. Plazzogna and G . Tagliavini Gazzetra 1970 100 990; ( g ) M . Devaud J . Chim. phys. 1971. 68 1043. 8 7 ( a ) M. Gielen N . Goffin and J. Topart J . Organometallic Chem. 1971 32 C38; ( b ) N. Serpone and K. A. Hersh Inorg. Nuclear Chem. Lerters 1971 7 115. '* ( a ) G. S. Brownlee A. Walker S. C. Nyburg and J . T. Szymanski Chem. Comm., 1971 1073; (6) F. H . Allen J . A. Lerbscher and J . Trotter J .Chem. Soc. ( A ) 1971, 2507. " ( a ) P. A. Yeats J. R . Sarns and F. Aubke Inorg. Chem. 1971,10 1877; (b) E. Lindner, U . Kunze and J. Koola J . Orgunometallic Chem. 1971,31 59; ( c ) R. C. Edmondson, D. S. Field and M. J. Newlands Canad. J. Chem. 1971,49 618; ( d ) E. Lindner and U. Kunze Z. Nuturforsch. 1971 26b 164; ( e ) B. F. E. Ford J . R. Sams R. G. Goel, and D. R. Ridley J . Inorg. Nuclear Chem. 1971 33 23. ')" ( a ) F. N. Srivastava and B. Misra J . Organomelallic Chem. 1971 32 331; (6) R. S. Randall R. W. J. Wedd and J . R. Sams ibid. 1971,30 C19; ( c ) F. P. Mullins Cunud. J . Chem. 1971,49 2719 314 D . W . A . Sharp M . G . H . Wallbridge and J . H . Holloway plexes between Ph,SnCl and sulphoxides are reported again with oxygen acting as the donor.The 1 1 complexes are considered as trigonal-bipyramidal and the 1 2 as octahedral with trans phenyl groups in contrast with the DMF deriva-tives similar complexes are reported for R,SnCl and RSnCl with phosphine-and arsine-oxides and triphenylpho~phine.~~' Both triphenyltin chloride and diphenyltin dichloride have molecular structures in the solid state ;91 these results are particularly significant since Mossbauer spectra of Ph,SnCl have been interpreted in terms of chloride bridging. Dimethyltinbis-(NN-dimethyl-dithiocarbamate) reacts with dihalogenoalkanes to give9 ionic species : S The details of significant structural determinations on several tin complexes have been published during the current year. Ditin(I1) ethylenediaminetetra-acetate dihydrate has the structure Sn"[Snl'Y],H,O,H,O ( H4Y = ethylene-diaminetetra-acetic acid).The outer Sn has seven oxygen neighbours from co-ordinated Y with presumably the lone pair occupying an eighth site. The inner Sn has distorted pentagonal-bipyramidal co-ordination with the nitrogens and the lone pair occupying equatorial position^.'^ The porphyrin entity in dichloro-octaethylporphinatotin(1v)bisnitromethane is essentially planar with the tin atom in the plane of the ring.94a However the phthalocyanine ring of dichloro-phthalocyaninatotin(1v) is crumpled presumably because of the size of the tin, the co-ordination about the tin is close to regular.94b Many adducts of tin halides with nitrogen-containing bases have been described. Amongst those where attempts have been made to define structure are the 1 1 and 1 2 complexes with pyrazines which appear to contain trans-MX,N skeletons with bidentate (bridging) or unidentate pyrazine l i g a n d ~ .~ ~ Molecular SnO may be formed in a krypton matrix by condensing together tin atoms and oxygen; it appears to be a linear molecule similar to carbon dioxide.96 Li,Sn03 has a rock-salt lattice; the oxygen atoms are in cubic close packing with two thirds of the octahedral holes occupied by lithium and one third by tin.97 Fluorostannate(1v) complexes [SnF,H,O]- and cis- and trans-[SnF,(H,O),] have been identified in aqueous solutions of tin(rv) fluoride ; 9 1 9 2 T. Tanaka K. Tanaka and T. Yoshimitsu Bull. Chem. SOC. Japan 1971,44 112. 9 3 F. P. Van Remoortere J. J. Flynn F.P. Boer and P. P. North Inorg. Chem. 1971, 10 1511. 94 ( a ) D. L. Cullen and E. F. Meyer jun. Chem. Comm. 1971 616; (b) D. Rogers and R. S. Osborn ibid. p. 840. 9 5 M. Goldstein and W. D. Unsworth Spectrochim. Acta 1971 27A 1055. 9 6 J. S. Anderson A. Bos and J. S. Ogden Chem. Comm. 1971 1381. 9 7 G. Kreuzberg F. Stewner and R. Hoppe Z . anorg. Chem. 1970 379 242. N. G. Bokii G. N. Zakharova and Y. T. Struchkov J . S t r u t . Chem. 1970 11 895; P. T. Greene and R. F. Bryan J . Chem. SOC. ( A ) 1971,2549 The Typical Elements 315 complexes are also formed with OH- and C1- ions.98" Tin(1v) halide adducts of phosphonous esters and phosphinous acids are 1 2 trans-oxygen-bonded the formulation of the 1 :2 tin(I1) halide adducts with a trans-planar co-~rdination~~' about tin appears unlikely.Tin@) fluoride adducts of pyridine-N-oxides are 1 2 adducts generally with a trans-configuration about tin although the cis-isomers are present for less bulky l i g a n d ~ . ~ ~ ~ The planar transition-metal compounds NN'-ethylenebis(salicyclideneaminato)metal(~~) (metal = Co Ni or Cu) react with tin(iv) and tin@) halides to form complexes which are probably held together by bonding from the oxygens of the co-ordinated ligand to the tin atom~."~ The existence of strong bonding between carboxylic acids and tin(1v) halides in DMF is shown by the optical activity which is intro-duced into the tin species when optically active acids are used.98f Ba,SnS has a K,SO,-type structure with isolated distorted SnS tetrahedra ;67b a distorted octahedral SnS6 group is found in tetrakis-(NN-diethyldithiocarbamato)tin(Iv), Sn(S,CNEt,) there are two bidentate dithiocarbamate groups and two cis-~ n i d e n t a t e .~ ~ " Dichlorobis-(NN-diethyldithiocarbamato)tin(Iv) Cl,Sn(S,-CNEt,) dissociates on heating to give first the isothiocyanato-complex Sn(NCS),Cl and then tin s ~ l p h i d e . ~ ~ ~ A Mossbauer spectroscopic study of the Sn-Se system establishes the existence of Sn,Se in addition to SnSe and SnSe .loo New stable mixed halides of tin(ii) SnClI SnBrI and Sn,C1Br3 l o l a as well as extensive ranges of mixed halogeno-anions SnX,Y- SnXYZ- in alkali-metal melts lo I b have been prepared and investigated spectroscopically. Tin(i1) fluoride forms 1 1 adducts with strong Lewis acid fluorides which on the basis of their spectroscopic properties are formulated as salts of the fluorine-bridged (Sn-F);' cation with complex fluoro-anions e.g.SbF,-. The 1 2 adduct with SbF and also Sn(SO,F) formed from tin@) fluoride and fluorosulphuric acid are regarded as tin(I1) salts e.g. Sn(SbF,),? with appreciable anion<ation interaction. lo2 Lead.-Flash photolysis of tetramethyl-lead and tetraethyl-lead yields fragments PbR positively identified by spectroscopy. O 3 The cleavage of hexaphenyldilead by mercury(I1) salts appears to involve intermediate formation of an unstable triphenyl-leadmercury derivative. Dialkyl-lead oxides which are normally 9 8 ( a ) Y. A. Buslaev and S. P. Petrosyants J. Struct. Chem. 1970 11 406; (6) A. A. Muratova E. G. Yarkova V. P. Plekhov A.A. Musina and A. N. Pudovik J. Gen. Chem. (U.S.S.R.) 1970 40 1966; (c) C. Owens N. M. Karayannis L. L. Pytlewski, and M. M. Labes J. Phys. Chem. 1971 75 637; (d) C. E. Michelson and R. 0. Ragsdale Inorg. Chem. 1970 9 2718; (e) M. D. Hobday and T. D. Smith J. Chem. Sac. ( A ) 1971 1453; (f) V. Doron and W. Durham J. Amer. Chem. Sac. 1971, 93 889. 9 9 ( a ) C. S . Harreld and E. 0. Schlemper Acta Cryst. 1971 B27 1964; (6) G. D'Ascenzo, V. Carunchio A. Messina and W. W. Wendlandt Thermochim. Acta 1971 2 211. l o o B. T. Melekh V. T. Shipatov and P. P. Seregin Znorganic Materials 1970 6 1348. l o ' ( a ) N. A. Shestakova E. M. Moroz V. S. Grigor'eva and S. S. Batsanov Russ. J. Inorg. Chem. 1971 16 10; (b) M. Goldstein and G. C. Tok J. Chem. SOC. ( A ) 1971, 2303; J.Barrett S. R. A. Bird J. D. Donaldson and J. Silver ibid. p. 3105. l o 2 T. Birchall P. A. W. Dean and R. J. Gillespie J. Chem. SOC. ( A ) 1971 177. C. L. Cook and I. M. Napier Austral. J. Chem. 1971 24 179. l o 4 V. G. Kumar Das D. A. Moyes and P. R. Wells J. Organometallic Chem. 1971,33,31 316 D . W . A . Sharp M . G . H. Wallbridge and J . H . Holloway prepared by dehydration of the corresponding dihydroxides may be obtained more cleanly by ozonolysis of the tetra-alkyl-lead. ' O5 Although acyl-lead compounds are unstable carbamoyl derivatives e.g. Ph,PbCOMe are formed from the organolead-lithium and the acid halide ; ' 06rr many triphenyl-lead derivatives of dicyanomethanido- and cyanamido-oxoanions e.g. Ph PbO,NC(CN) have been prepared from the organolead chloride and the appropriate silver salt.'06b Lanarkite Pb,OSO, contains trigonal-pyramidally co-ordinated lead ;' 07' a bromoapatite of lead Pb,,(PO,)6Br, may be prepared by sintering equal amounts of Pb3(P04) and PbBr .' 0 7 b Tetraethylammonium tris(ethylxanthat0)-lead(II) NEt,Pb(S,COEt) has a pentagonal-pyramidal co-ordination of sulphur atoms surrounding the lead the lone pair presumably occupying the open face of the pyramid. "" Non-metal derivatives of pentafluorothiophenol e.g. (C,F,S),P are easily prepared from the appropriate halide and Pb(SC6F,),.'08b As with the corresponding chlorides vapour species MPbBr (M = Na K Rb, or Cs) are found over molten PbBr,-MBr mixtures.'09 2 GroupV Nitrogen.-The behaviour of nitrogen atoms in inorganic carbide matrices has been studied by introducing 13N atoms by the '2C(d,n)'3N reaction.On hydrolysis the methanide A14C3 gave NH and MeNH whereas acetylides gave NH CN- and MeCN.' lo An extended discussion has been given on solution phenomena including acid-base descriptions in liquid ammonia. ' ' '* The microwave spectrum of methylhydrazine suggests that two rotamers are present;"lb the i.r. spectrum of solid di-imide N,H, shows only the trans-form. '' '' The autoxidation of hydroxylamine in aqueous alkali proceeds by attack of oxygen on the deprotonated species NH,O- to give NO- which is oxidized to ONOO-. The peroxonitrite ion isomerizes slowly to nitrate although it is stabilized in the presence of ethylenediaminetetra-acetic acid. ' I d NH and H,CN radicals are formed during the radiolysis of frozen aqueous solutions of alkali-metal azides and cyanides ; they may have been produced by protonation of the species NH- and HCN-.' ' le Tris(methylmercury)amine N(HgMe) , formed by the reaction between ammonia and MeHgN(SiMe,) is pyramidal in shape whereas the isoelectronic species [O(HgMe),] + formed from O(HgMe), and MeHgN, is planar." As with the NCS group the mode of bonding of the l o 5 Y .A. Aleksandrov and N. G. Sheyanov J . Gen. Chem. (U.S.S.R.) 1970 40 1889. l o 6 ( a ) L. C . Willemsens J . Organometallic. Chem. 1971,27,45 ; ( b ) H. Kohler B. Eichler, and R. Salewski Z . anorg. Chem. 1970,379 183. lo' ( a ) K. Sahl Z . Krist. 1970 132,99; (b) V. M. Bhatnagar Inorg. Nuclear Chem. Letters, 1971 7 231. l o * ( a ) W.G . Mumme and G. Winter Znorg. Nuclear Chem. Letters 1971,7,505; (6) M. E. Peach and H. G. Spinney Canad. J . Chem. 1971,46 644. l o 9 H. Bloom and R. G . Anthony Austral. J . Chem. 1971 24 2001. ' l o M. J. Welch and J. F. Lifton J . Amer. Chem. SOC. 1971 93 3385. '11 ( a ) J. J. Lagowski Pure Appl. Chem. 1971 25 429; (b) R. P. Lattimer and M. D . Harmony J . Chem. Phys. 1970,53 4575; ( c ) A. Trombetti J . Chem. Soc. ( A ) 1971, 1086; (d) M. N. Hughes and H. G. Nicklin ibid. p. 164; ( e ) I. S . Ginns and M . C. R. Symons Chem. Comm. 1971 893. l 2 W. Thiel F . Weller J. Lorbeth and K. Dehnicke Z . anorg. Chem. 1971 381 57 The Typical Elements 317 NCO group can be readily determined from the I4N chemical shifts of com-plexes. ' ' Although reactions of hexafluoroisopropylidenimine (CF,),C=NH, with non-metal halides result in addition across the double bond hexafluoro-isopropylideniminates e.g.As[N=C(CF,),] , of many non-metals are formed by reaction of LiN=C(CF,) with chlorides or fluorides. The symmetrical sulphinyl compound is not formed from thionyl halides however but instead O=S=NC(CF,),N=C(CF,) results. ' l4 Bis(trifluoromethyl)nitroxyl (CF,),-NO. has molecular dimensions similar to those of (CF,),NN(CF,) rather than CF,NO which has much closer similarities to the nitrosyl halides.' '' N N -Difluoroperfluorocarboxamides R,(CO)NF are formed when the HNF ,KF complex reacts with perfluoroacyl fluorides.' 16a Tetrafluorohydrazine reacts photolytically with C1,CCN to give F,NCCl,CN and F,NCCI in reactions which clearly involve NF radicals ; polyhalogenoketones react to give difluoro-aminopolyhalogenomethanes and sulphuryl chloride gives F,NSO,Cl.Dechlorofluorination of F,NCCI,CN gives the two forms of FN=C(CN)Cl in equimolar quantities. ' ' 6b Chlorine monofluoride adds to halogenoimines e.g. Cl,C=NF generally by chlorine addition at nitrogen to give halogenoamines, e.g. Cl,FCNFCl which as mentioned above are readily dehalogenated with mercury to imines. ' ' 6c Perfluoroacyl- and perfluoroalkyl-iminosulphurdi-fluorides e.g. FC(O)N=SF lose sulphur tetrafluoride when treated with chlorine monofluoride to give NN-dichloro-compounds e.g. FC(O)NCl .' 6d FSO,N=S=O reacts similarly by loss of SOF to give FSO,NCl ; this dichloro-amine is hydrolysed by water to acidic FSO,NClH which may be isolated in the form of its salts.' 16e When condensed into a nitrogen matrix dinitrogen trioxide can be isomerized into an extended symmetric configuration O=N-0-N=O by near4.r.radiation ;' 17' dinitrogen tetroxide reacts with hydrogen atoms at very low temperatures to give dinitrogen trioxide.' ' 7 b Compressed nitrous oxide is hydrated in the gas phase probably to N=N(OH) or O=N(NH)OH;"" gaseous nitrous acid HONO exists in both cis- and trans-forms and the molecular constants of both forms are now known ; the O N 0 and NOH angles are opened up in the cis molecule but the central N-0 bond in the cis molecule is un-expectedly shorter than in the trans-isomer and the OH and N=O bonds correspondingly longer. Overall there is an increased contribution of the structure in the cis-form relative to the trans.' '* When NO, ' I 3 K.F. Chew W. Derbyshire N . Logan A. H. Norbury and A. I. P. Sinha Chem. Comm. 1970 1708. 'I4 R. F. Swindell T. J. Ouellette D . P. Babb and J. M. Shreeve Znorg. Nuclear Chem. Letters 1971 7 239. '" C. Glidewell D. W. H. Rankin A. G. Robiette G . M. Sheldrick and S. M. Williamson, J . Chem. SOC. ( A ) 1971,478. ( a ) R. A. De Marco and J. M. Shreeve Znorg. Chem. 1971,10,911; ( 6 ) L. M. Zaborowski and J. M. Shreeve ibid. p. 407; ( c ) R. F. Swindell L. M. Zaborowski and J. M. Shreeve ibid. p. 1635; (d) R. A. De Marco and J. M. Shreeve Chem. Comm. 1971, 788; ( e ) H. W. Roesky Angew. Chem. Znternat. Edn. 1971 10,265. ( a ) E. L. Varetti and G. C. Pimentel J . Chem. Phys. 1971 55 3813; ( b ) P.M. A. Sherwood J . Chem. SOC. ( A ) 1971,2478. 'I8 A. P. Cox A. H. Brittain and D. J. Finnigan Trans. Faraday Soc. 1971 67 2179. Hi ,-0 O= 318 D . W. A . Sharp M . G . H . Wallbridge and J . H. Holloway and NO are co-deposited with alkali metals in argon matrices species M,+N02-and M,+NO- are formed. Sodium reacts with argon-NO-N,O mixtures to give N,O,- NO,- and Na,+NO,- species after irradiation.' '' The highly unstable compound nitrodifluoroamine O,NNF, is formed from N2F4 and NO,. ' 2o N-Halogeno-derivatives ClNS(O)F and BrNSF readily add across the double bonds of fluoro-olefins to give e.g. CIF,CCF,NS(O)F Trifluoro-ammonium ions NF3H+ have been detected by ion cyclotron resonance spectro-scopy in mixtures of NF and methane or hydrogen chloride.Examination of the spectra gives a H-N+ bond strength of 138 f 10 kcal mol-' compared with 128 f 3 kcal mol-' for NH4+ ; in the absence of solution effects the pK of NF3Hf in aqueous solution is estimated to be -31.',, Phosphorus.-Yellow phosphorus dissolves in disulphuric acid to give P,* + cations which are blue and P42+ cations which are c ~ l o u r l e s s . ' ~ ~ Phosphorus oxy-compounds are protonated in fluorosulphuric acid and in HS0,F-SbF, solution. The site of protonation is generally the oxygen of a P=O group but triorganophosphites are protonated at the phosphorus.' 24a In crystalline phosphonium bromide as in PH41 but unlike ammonium halides the PH bonds are directed at the four next-nearest neighbour halides.' 24b There is little definite structural information on compounds containing P-H bonds.An ab initio theoretical calculation on methylphosphine shows that the relative stability of the three forms is staggered > semi-eclipsed > eclipsed (cf. the structure of Me,P p. 320);'25a a microwave study of F,HP,BH, indicates a tilt of the borane group away from the fluorine atoms.125b A new mixed secondary phosphine Ph(Me,Si)PH is formed by trimethylsilylation of potassium phenylphosphide ; its reactions are those normally expected for a secondary phosphine but the Si-P bond is cleaved by bromine.'26 Sodium sulphonyl and phosphoryl amides react with Me,PCl to give P-H compounds e.g. R,P(H)=NY rather than R,P-NHY.' 27 The previously unknown dialkoxy-phosphines (RO),PH are prepared by reduction of (RO),PCI with organotin hydrides bistrialkylsilyl derivatives (R,SiO),PH are formed from ammonium hypophosphite and silylamines or disilazanes.' 28b Both series are very reactive; (RO),PH compounds can be oxidized by NO to (RO),P(O)H l 9 D.E. Milligan and M. E. Jacox J . Chem. Phys. 1971,55 3404. l Z o P. A. Sessa and H. A. McGee jun. Inorg. Chem. 1971 10 2066. 1 2 ' l Z 2 D. Holtz J. L. Beauchamp W. G. Henderson and R. W. Taft Inorg. Chem. 1971, R. Mews and 0. Glemser Inorg. Nuclear Chem. Letters 1971,7 821 823. 10 201. R. C. Paul J. K. Puri and K. C. Malhotra Chem. Comm. 1971 1031. and J. J. Rush J. Chem. Phys. 1971,54 1968. Kuczkowski J . Chem. Phys. 1971,54 1903. l Z 4 ( a ) G. A. Olah and C. W. McFarland J . Org. Chem. 1971,36,1374; (b) L. W. Schroeder l Z 5 ( a ) I.Absar and J. R. Van Wazer Chem. Comm. 1971,611 ; ( b ) J. P. Pasinski and R. L. 1 2 6 M. Baudler and A. Zarkadas Chem. Ber. 1971 104 3519. 1 2 ' A. Schmidpeter and H. Rossknecht 2. Naturforsch. 1971 26b 81. l z 8 ( a ) I. F. Lutsenko M. V. Proskurnina and A. A. Borisenko Organometallics in Chem. Synth. 1970/1 1 169; (b) M. G. Voronov and L. Z. Marmur J . Gen. Chem. (U.S.S.R.) 1970,40,2121 The Typical Elements 319 and by sulphur to (RO),P(S)H. Tetramethyldiphosphine forms tetramethyldi-phosphonium chloride [Me,P.PHMe,]Cl with hydrogen chloride ; the phos-phonium salt decomposes to Me,PH and Me,PCl. Chlorodimethylphosphine gives Me,P(O)H with water this disproportionates to Me,PH (as the phos-phonium salt Me,PH,Cl) and Me,P(0)OH.'29 White phosphorus and hydrogen iodide form the previously unknown iodophosphines PH,I and PHI when reacting to give PH and P,14 ; the mixed hydrido-iodide compounds are present in mixtures of phosphine and phosphorus iodides.' 30 Difluorophosphine oxide, F,HPO may be prepared very simply by fluorination of phosphorous acid with zinc fluoride in the presence of PBr ; I 3 l a phosphorus hydrides MePF,HX, (X = C1 NEt, OPr' or F) are formed by addition of HX to MePF2.13" The most popular reaction of P-H bonds reported during the year has been addition to double bonds to give derivatives which are sometimes potential chelating agents. Species prepared include X,SiCH,CH,PMe X,Si(CH,CH,-PMe,) ,' 32Q R,PCH,CH,PHR ' (R,PCH2CH,),PR','3 2b3c (R,PCH,CH,) P, CH,NC (also P~,AsCH,CH,NC),'~'~ Ph,PCH,CH,PH, and P(CH,CH,-PPh,) .' 32e Similar compounds e.g.PhCH=CHP(H)Ph are formed by hydrolysis of the adduct between an alkali-metal phenylphosphide and phenyl-acetylene.' 2f Methylmercury derivatives of phosphorus [P(HgMe),]X (X = BF, PF, or SbF,) of the same series as those described previously for nitrogen and oxygen are formed from the reaction between phosphine and MeHgX compounds.' 33 Phenylphosphinidene PhP is postulated as an intermediate in reactions which lead ultimately to cyclophosphines and evidence for its presence is given by trapping the monomer with other active species. 134 Various phosphorus-containing radicals have been prepared by y-irradiation of trialkylphosphines or alkylphosphonium salts reduction of arylphosphines or phosphole oxides by electrolysis or by the use of alkali metals or by trapping during the course of reactions; e.s.r.spectra have been recorded and there is no evidence for C-X (d + p)n-bonding in the alkyl-substituted derivatives whereas there is strong evidence for such bonding or hyperconjugation in the aryl-substituted cases.I3 R,P(CH,),PPh(CH,),PPh(CH,),PPh, Ph,PCH,CH,AsPh ,' 2c Ph2PCH2-F. See1 and K.-D. Velleman Chem. Ber. 1971 104 2967 2972. M. Schmidt and H. H. J. Schroder Z . anorg. Chem. 1970,378 185 192. 1 3 ' ( a ) E. A. Dietz jun. and R. W. Parry Inorg. Chem. 1971 10 1319; ( 6 ) V. V. Sheluchenko G. I. Drozd M. A. Landau S. S. Dubov and S. Z. Ivin J . Struct. Chem. 1970,11,623. ( a ) J. Grobe and U. Moller J . Organometallic Chem. 1971 31 157; ( b ) K. Issleib and H.Weichmann Z . Chem. 1971 11 188; (c) R. B. King and P. N. Kapoor J . Amer. Chem. SOC. 1971 93 4158; (d) R. B. King and A. Efraty ibid. p. 564; ( e ) R. B. King and P. N. Kapoor Angew. Chem. Internat. Edn. 1971 10 734; (f) K. Issleib, H. Bohme and C. Rockstroh J. prakt. Chem. 1970,312 571. ' j 3 D. Breitinger K. Geske and W. Beitelschmidt Angew. Chem. Internat. Edn. 1971, 10 5 5 5 . M. J. Gallagher and I. D. Jenkins J . Chem. SOC. ( C ) 1971 593. 1 3 5 F. Gerson G. Plattner and H. Bock Helv. Chim. Acta 1970 53 1629; A. Begum, A. R. Lyons and M. C. R. Symons J . Chem. SOC. ( A ) 1971,2388; H. Karlsson and C. Lagercrantz Acra Chem. Scand. 1970,24,3411; A. R. Lyons and M. C. R. Symons, Chem. Comm. 1971 1068; C. Thomson and D. Kilcast ibid. p. 782 3 20 D .W. A . Sharp M . G . H . Wallbridge and J . H . Holloway In trimethylphosphine as in other methylphosphines and methylamines the methyl groups are tilted toward the lone pair on the central atom.136o Tri-ethynylphosphine P(C-CH) has pyramidal co-ordination about phosphorus but the P-C-C bonds are non-linear as in P(C-CPh) and P(CN),.136b Vibrational studies on P(C-CH) and As(C-CH) suggest some d-orbital participation in the M-C bonds,'36c a fact which may account for the non-linearity. Tetrakis(pentafluorophenyl)cyclotetraphosphane (PC6F5)4 has a non-planar ring with C6F5 groups in the equatorial position^.'^' The PCP angle in methanetetra-allylbis(triphenylphosphorane) Ph,P=C=PPh is 145" and 131" in the two independent molecules in the cell; this is similar to the angle in isoelectronic P=N=P compounds.' 38 In last year's report we commented on the stabilization of alkylphosphoranes in cyclic derivatives ; it has now been shown that homocubyltrimethylphosphorane (63) and other homocubyl deriva-tives are stable ; the stability is considered to reside in the fact that base bonds to + &TPMe3 (63) phosphorus instead of removing hydrogen because of the ring strain in the homocubyl group.139 Dialkylperfluoroacylphosphines R,C(0)PR2 are formed by reaction between the acyl chloride and sodium pho~phide;'~'" oxygen oxidizes R,COPR compounds to racemic R,P(O)-C(R,)H.OP(O)R in a general rea~tion.'~'" The chemistry of acylphosphites has been revie~ed.'~'' Phospha-benzene (64) arsabenzene and stibabenzene analogues of pyridine are formed from (65) and the appropriate trihalide followed by dehydrohalogenation with 1,5-diazabicyclo[4,3,O]non-5-ene ; it is not yet clear whether these compounds show aromatic character'41u but they should be interesting ligands and inter- -1 3 6 ( a ) P.S. Bryan and R. L. Kuczkowski J . Chem. Phys. 1971 55 3049; (6) J . Kroon, J. B. Hulscher and A. F. Peerdeman J . Mol. Structure 1971,7,217; (c) W. M. A. Smit and G . Dijkstra ibid. p. 223 263. ' 3 7 F. Sanz and J. J. Daly J . Chem. Soc. ( A ) 1971 1083. 1 3 ' A. T. Vincent and P. J . Wheatley Chem. Comm. 1971 582. 1 3 9 E. W. Turnbloom and T. J. Katz J . Amer. Chem. Soc. 1971.93 4065. ' ' O ( a ) E. Lindner and H.-D. Ekert Z . Nuturforsch. 1971 26b 733; (6) Angew. Chem. Internat. Edn. 1971 10 565; E.Lindner H.-D. Ekert K. Geibel and A. Haag Chem. Ber. 1971 104 3121; ( c ) E. E. Nifant'ev and I. V. Fursenko Russ. Chem. Rev. 1970, 39 1050. 14' ( a ) A. J . Ashe J . Amer. Chem. SOC. 1971 93 3293 6690; (6) W. P. Ozbirn R. A. Jacobson and J. L. Clardy Chem. Comm. 1971 1062 The Typical Elements mediates. The structure of 1,2,5-triphenylphosphole pyramidal co-ordination about phosphorus with no 32 1 (66) shows essentially evidence for aromatic P h - - j j P h P Ph character in the phosphole ring. l 4 l b A new synthesis of penta-aryl-phosphoranes from lithium aryls and (PhO),PNS(O),Tol has been described ;142a the aryl groups on phosphines even when initially co-ordinated are replaced quite readily e.g. (Ph,P),NiCl and MeMgBr give methylphenylphosphines.’42b Cyanophosphines e.g.Ph,PCN are rapidly prepared from chlorides and silver cyanide using acetonitrile as s01vent.l~~ Me,PPCF, prepared from Me,P and (CF,P), is stabilized by co-ordination in the 1 1 and 1 2 borane adducts; spectra suggest that the CF,P group is the bonding site.’44 Whereas the structures of tri-o-tolylphosphine and tri-o-tolylphosphine oxide are unexcep-tional the selenide has an arrangement with one methyl not equivalent to the other two; in the solid this unique methyl is situated behind the phosphorus, almost on the Se-P axis. Tri-o-tolylphosphine sulphide probably has a similar conformation at low temperatures. 14’ General summaries have been given on the stereochemistry of optically active three- and four-co-ordinate phosphorus compounds.146a Partial resolution of racemic tertiary phosphines may be effected by use ofasymmetric palladiumcomplexes ;146b it has been shown that the absolute configurations of the epimeric methyl methylphosphinates are the reverse of those previously reported data which have caused considerable rethinking of the stereochemistry of a series of phosphorus derivative^.'^^' The barrier to inversion in acylphosphines and in compounds PhRPMMe (M = Si Ge or Sn) (ca. 19 kcal mol- ’) is considerably lower than in diarylalkyl- and aryldialkyl-phosphines the low energy barrier probably arises through enhanced (p -+ p)n conjugation in the planar transition state between the phosphorus and the carbonyl group 14” or may be due merely to the electronegativity of the Group IV element.147b A great deal of work has been published on the mechanisms of reactions of organophosphorus derivatives but no attempts will be made to cover these areas in the present review; the reader is referred to the Chemical Society Specialist Periodical Report ‘Organophosphorus Chemistry’ Volume 3.1 4 2 ( a ) M. Schlosser T. Kadibelban and G. Steinhoff Annafen 1971,743,25; (6) M. L. H. 143 C. E. Jones and K. J. Coskran Znorg. Chem. 1971 10 1536. ‘ 4 4 A. B. Burg J . Znorg. Nuclear Chem. 1971,33 1575. 1 4 5 R. A. Shaw M. Woods T. S. Cameron and B. Dahlen Chem. and Znd. 1971 151. 146 ( a ) H. Christol and H.-J. Cristau Ann. Chim. (France) 1971 6 179,203; (6) S. Otsuka, A. Nakamura T. Kano and K. Tani J . Amer. Chem. SOC. 1971,93 4301 ; (c) W. B. Farnham R.K. Murray jun. and K. Mislow Chem. Comm. 1971 605. 14’ ( a ) W. Egan and K. Mislow J . Amer. Chem. SOC. 1971 93 1805; (6) R. D. Baechler and K. Mislow ibid. p. 773. Green M. J. Smith H. Felkin and G. Swierczewski Chem. Comm. 1971 158 322 D . W. A . Sharp M. G . H . Wallbridge and J . H . Holloway Several structures have been determined where phosphorus is interacting with ring systems. Cyclopropylphosphine has the symmetric conformation that allows maximum interaction of the phosphorus lone pair with the intra-annular orbitals of the cyclopropyl ring ; 14" 1-0x0-1-chlorophosphacyclopent-3-ene (67) has an envelope-shaped ring with the carbon atoms in a plane the P=O bond is cis relative to the double bond:'48b the phosphorinan derivatives (68) have axial phenyl groups with a chair conformation for the ring:'48' NN'-dicyclohexylphenylphosphonothioic diamide (69) has a distorted cyclohexyl (68) (69) (a) R' RZ = 0 (b) R' = RZ = Me ring attached to a central heterocylic ring with a conformation between boat and chair ; the phosphorus has tetrahedral co-ordination and the bonding about systems generally approximates to the chair form ; if an additional P=O bond is present it is equatorial with respect to the ring other substituents are generally axial trisneopentyl and tris(P-chloroethyl) phosphate have the alkyl groups and phosphate in trans orientations ;148f 2,5-dithio-l-thiophosphoruscyclopentanes (70) have strained rings but tetrahedral co-ordination about phosphorus.148g In the phosphinohydrazine skeleton P-N-N the phosphorus is normally the most basic atom but in (CF,),P-NMe.NH the terminal nitrogen is the most basic because of effects of the electronegative trifluoromethyl groups.149 Phosphazanes RR'PN(EMe,) (E = Si or Ge) as well as phosphazenes RR'(Me,E)P=NSiMe (E = Ge Sn As or Sb) are formed from RR'P.NLi.EMe, /o-c\ nitrogen is almost planar:'48d the ring conformation in P \ 0-c 14' ( a ) L.A. Dinsmore C. 0. Britt and J. E. Boggs J . Chem. Phys. 1971,50,915; (b) V. A. Naumov and V. N. Semashko J . Struct. Chem. 1970 11 919; (c) A. T. McPhail, J. J. Breen J. H. Somers J. C. H. Steele jun. and L. D . Quin Chem. Comm. 1971, 1020; A. T. McPhail J. J. Breen and L. D . Quin J . Amer. Chem. SOC. 1971 93, 2574; ( d ) J. D. Healy E. M. H. Ibrahim R. A. Shaw T. S. Cameron K.D. Howlett, and C. K. Prout Phosphorus 1971 1 157; ( e ) R. C. G. Killean J. L. Lawrence and I. M. Magennis Acta Cryst. 1971 B27 189; M. G. B. Drew J. Rodgers D. W. White, and J. G. Verkade Chem. Comm. 1971 227; J. Rodgers D. W. White and J . G. Verkade J . Chem. SOC. (A) 1971 77; W. G. Bentrude K. C. Yee R. D. Bertrand and D. M. Grant J. Amer. Chem. SOC. 1971 93 797; V. A. Naumov and N. M. Zaripov, J . Struct. Chem. 1970 11 1030; cf A. A. Bothner-By and W.-P. Trautwein J . Amer. Chem. Soc. 1971,93 2189; ( g ) J. D. Lee and G. W. Goodacre Acta Cryst. 1971 B27, 1055 1841. ' 4 9 L. K. Peterson and G. L. Wilson Canad. J . Chem. 1971,49 3171 The Typical Elements 323 and organoelement halides.' Azides and isocyanates e.g. MeP(O)(N,) are formed from the appropriate chloride and sodium pseudohalide ; RP(NCO), (70) R = Ph or C1 compounds are oxidized to RP(S)(NCO) by C1,PS.The PNCO group con-denses with hydrogen-containing species to give e.g. PNHCOR with ROH; PN groups react with triorganophosphines to phosphoranylidene derivatives,' '' e.g. MeP(O)(NHCO,R)N + PR; + MeP(O)(NHCO,R)N=PR: Methyleneiminophosphines X'X2P-N=CR'R2 prepared from X'X2PC1, HN=CR'R2 and Et,N are nucleophilic at phosphorus and electrophilic at carbon. When R = 0-alkyl Michaelis-Arbusov-type rearrangements take place to form acylphosphinimines e.g. Ph,P(Me)=NC(R)=0.'52" Ditertiary bi-phosphines react with CC1 and amines to give bis(aminophosphonium)chlorides which are deprotonated to N=P-[C],-P=N type compounds. lS2' Sodium salts of hydroperoxides react with PC1 bonds to give peroxy-derivatives e.g.ArSO,N=P(Ph)(OOBu') .Is3 Aminolysis of the appropriate chloride forms derivatives (CF,),P(E)NHMe and F,P(E)NHMe (E = 0 or S).lS4 Tetra-alkoxydiphosphines (RO),PP(OR')2 can be prepared from the reaction of (RO),PH with ClP(OR') or the symmetrical compounds from (R0)2PC1, RkSnH and Et,N.' 55 Various relatively stable Michaelis-Arbuzov inter-mediates (neopentylO),PMeI [BrP(OCH,),CMe]Br and R,P(OR'),I have been isolated and their reactions studied by n.m.r. spectro~copy.'~~ A new mechanism turnstile-rotation by which ligand equivalence is attained in trigonal-bipyramidal compounds e.g. P(OR) and PF has been proposed ; in the Berry pseudorotation picture positional interchange is achieved by pairwise exchange of apical and equatorial ligands (7 1) whereas the turnstile mechanism corresponds to an internal rotation of one apical and one equatorial group as a pair uersus ' 5 0 0.J. Scherer and W. Gick Chem. Ber. 1971 104 1490. 15' Z. M. Ivanova S. K. Mikhailik and G. I. Derkach J. Gen. Chem. (U.S.S.R.) 1970, 40 1459; V. A. Shokol L. I. Molyavko N. K. Mikhailyuchenko and G. I. Derkach, ibid. 1971,41 312; V. A. Shokol G. A. Golik and G. I. Derkach ibid. p. 539; E. S. Gubnitskaya A. G. Matyusha and G. I. Derkach ibid. 1970,40 1197. 1 5 2 (a) A. Schmidpeter and W. Zeiss Chem. Ber. 1971,104 1199; (b) R. Appel B. Blaser, R. Kleinstuck and K.-D. Ziehn ibid. p. 1847. 1 5 3 T. I. Yurzhenko and A. G. Babyak J. Gen. Chem. (U.S.S.R.) 1970,40 1651. R. G. Cavell T. L. Charlton and W.Sim J. Amer. Chem. SOC. 1971,93 1130. 1 5 5 A. L. Chekun M. V. Proskurnina and I. F. Lutsenko J. Gen. Chem. (U.S.S.R.), 1970,40,2502. H. R. Hudson R. G. Rees and J. E. Weekes Chem. Comm. 197 1,1297 ; A. I. Razumov, B. G. Liorber T. V. Zykova and I. Y. Bambushek J. Gen. Chem. (U.S.S.R.) 1970, 40 2009; G. K. McEwen and J. G. Verkade Chem. Comm. 1971 668; CJ D. H. Brown K. D. Crosbie G. W. Fraser and D. W. A. Sharp J. Chem. SOC. ( A ) 1969,872. 324 D. W. A . Sharp M . G. H. Wallbridge and J . H . Holloway the oppositely rotating trio of the remaining ligands (72).' 5 7 Alkali-metal iodides dissolve in (Pr'O),P(O)Me to give complexes ; the complexes subse-quently give pyromethylphosphonates ;' 58u Ph,P(O)CH,C(O)Ph forms 1 1 complexes with lithium salts.'58b Nitric oxide is a good oxidizing agent for trifluoromethylphosphines ; (CF,),PF and (CF,),P.P(CF,) give the new com-pounds (CF,),P(O)F and (CF,),P(0).0.P(O)(CF3) respectively.' 5 9 F* F' F' F I .-F (71) (72) Phenylphosphinothioylidene PhP=S has been postulated as an intermediate formed during the dechlorination of PhP(S)Cl with magnesium ; it reacts with many substrates.I6' Dithiophosphinic acids RR'P(S)SH are conveniently prepared by nucleophilic fission of RP PR compounds with Grignard re-agents R'MgX;'6'" many salts of these of Ph,PSe,- and oi the related (EtO),POS - ions have been prepared and examined spectroscopically.l 6 ' (CF,),P(S)I reacts with mercury to give the unsymmetrical product (CF3)2-P(S)SP(CF,) ; this compound may also be synthesized by reaction between (CF,),P(S)SH and (CF,),PNMe or (CF,),PCl.Bromination of metal bis-(trifluoromethy1)dithiophosphinates gives the diphosphinetetrasulphide (CF,),-P(S)SSP(S)(CF,) . 162 Stable dimethyltetrafluorophosphates are prepared from the reaction s s s I I / \ I I \ / S Me,SiN=PR + Me,PF -+ [Me,P(N=PR,),][Me,PF,] the geometry of the anion is not completely established but it is probably the trans-isomer. ' The structure of the phosphorane ylide Ph,PNS(O),Tosyl, shows considerable shortening of the P-N bond compared with the normal 1. Ugi D. Marquarding H. Klusaceck P. Gillespie and F. Ramirez Accounrs Chem. Res. 1971 4 288; F. Ramirez S. Pfohl E. A. Tsolis J. F. Pilot C. P. Smith 1. Ugi, D. Marquarding P. Gillespie and P. Hoffmann Phosphorus 1971 1 1 .(a) N. M. Karayannis C. M. Mukulski M. J. Strocko L. L. Pytlewski and M. M. Labes Znorg. Chim. Acra 1971 5 357; (b) C. N. Lestas and M. R. Truter J . Chem. Soc. ( A ) 1971,738. R. C. Dobbie J. Chem. SOC. ( A ) 1971 2894. S. Nakayama M. Yoshifuji R. Okazaki and N. Inamoto Chem. Comm. 1971 1186. 1 6 ' (a) K. Diemert and W. Kuchen Angew. Chem. Internat. Edn. 1971 10 508; (b) H. Hertel and W. Kuchen Chem. Ber. 1971 104 1735 1740; A. Miiller V. V. K. Rao, and G. Klinksiek ibid. p. 1892; A. Muller P. Christophliemk and V. V. K. Rao, ibid. p. 1905; C. M. Mikulski N. M. Karayannis and L. L. Pytlewski Inorg. Nuclear Chem. Letters 1971 7 785. 1 6 2 A. A. Pinkerton and R. G. Cavell J. Amer. Chem. SOC. 1971 93 2384. 1 6 3 W. Stadelmann 0. Stelzer and R. Schmutzler Chem.Comm. 1971 1456 The Typical Elements 325 covalent bond length in agreement with strong ( d - p ) ~ overlap ; sulphur ylides show a similar bond shortening. 164a [Ph P-N-PPh,] [Cr,(CO) J] is formed from chromium hexacarbonyl and (Ph,P),NI. One phenyl group on each phosphorus is bent in such a way as to give a cisoid-pentadienyl type arrangement. Other similar cations have other conformations ; thus [(NH,)Ph,P-N-PPh,(NH,)] + and several unsym-metrically substituted derivatives have transoid-conformations. 64b Hexamethylphosphoric triamide (Me,N),PO reacts in the presence of alkyl iodides to give salts (Me,N),POP(O)(NMe,),X-. 165 Trihalogenoiminophos-phoranes react with alcohols apparently initially to give POR compounds which easily rearrange to place the R substituent elsewhere in the molecule.Thus XSO,N=PCl react with ROH to give initially XSO,N=PCl,OR but these rearrange to XSO,NR.P(O)Cl whereas S=PF,N=PF gives MeS-PF,=N.-P(O)F with methanol.166 The several methods (direct interaction of amines with phosphorus chlorides or fluorides ; redistribution reactions between e.g. aminophosphines and fluoro- or chloro-phosphines ; reactions of aminophos-phines with alcohols and of phosphites with aminophosphines) for the prepara-tion of P"'-NR,-C1(F)-OR1 compounds have been discussed and a range of compounds described. 16' The aminophosphine F,PNH is prepared by the gas-phase reaction of ammonia with bromodifluorophosphine ; other species (F,P),NH and (F,P),N are only formed incompletely; both Me,NPF and H,NPF have a staggered conformation in the gas phase.16* MeNHPF4169" and piperidylfluorophosphoranes (73)' 69b are formed from silylamines and + + Me Ph,PF - , ( 7 3 ) fluorophosphoranes ; these compounds tend to have non-equivalent axial fluorine atoms and non-equivalent equatorial fluorines are found in the piperidyl derivatives.Aminofluorophosphines form adducts with chlorine and bromine, I64 165 166 167 168 1 6 9 (a) A. F. Cameron N. J. Hair and D . G. Morris Chem. Comm. 1971 918; (b) L. B. Handy J. K. Ruff and L. F. Dahl J . Amer. Chem. SOC. 1970,92 7327. C. Anselmi B. Macchia F. Macchia and L. Monti Chem. Comm. 1971 1 152. H. W. Roesky and W. G. Bowing Chem. Ber. 1971 104 3204; H. W. Roesky and L. F. Grimm Chem. Comm. 1971,998. S. Senges M. Zentil and M.-C.Labarre Bull. SOC. chim. France 1971 351 ; M. Zentil, S. Senges J.-P. Faucher and M.-C. Labarre ibid. p. 376. D . W. H. Rankin J . Chem. SOC. ( A ) 1971 783; G. C. Holywell D . W. H. Rankin, B. Beagley and J. M. Freeman ibid. p. 785; cf. J. E. Smith and K. Cohn J . Amer. Chem. SOC. 1970,92 6185. (a) J. S. Harman and D. W. A. Sharp Inorg. Chem. 1971,10,1538 ; (6) M. J. C. Hewson, S. C. Peake and R. Schmutzler Chem. Comm. 1971 1454; ( c ) G. I. Drozd M. A. Sokal'skii 0. G . Strukov and S. Z. Ivin J . Gen. Chem. (U.S.S.R.) 1970 40 2384 326 D . W . A . Sharp M . G . H. Wallbridge and J . H. Holloway the adducts generally having trigonal-bipyramidal co-ordination about phos-phorus(v) although (R2N),PFX2 and R'(R2N)PFX2 are formulated with phosphonium ions [(R,N),PFX] + and [R'(R,N)PFX] + re~pectively.'~~' Chloro-phosphines react with SbCI,N to give azidophosphonium hexachloroanti-monates(v) e g .[Me,P(N,),] [SbCl,]. ' 70 Substituted bromoiminophosphoranes, e.g. RSO,N=PBr,NMe, are readily formed by substituting the parent tribromides with e.g. dimethylaminosilanes.' Aminodifluorophosphine reacts with dichlorotrifluorophosphorane to give trifluorophosphazodifluoro-phosphine F,P=NPF ;' 7 2 a other simple preparations of PNP compounds which have been reported include PF,.NMe.PF and PF,.NMe-P(O)F from Me,Si.NMe.PF and phosphorus fluorides ;' 7 2 b F,P(S)-NMe.P(O)F from Me,Sn.NMe.PSF and P,O,F4 ;*' the almost quantitative preparation of C1 PNP(O)Cl from phosphorus pentachloride and ammonium sulphate ;' 72c and the formation of [Cl,P=N-PCI,]+ ions from phosphorus pentachloride and BF,,NH .' 7 2 d Phosphazosilazanes e.g. Me,Si.NMe-PCl,=NSO,CI are import-ant intermediates in the preparation of phospha~enes.'~~~*' Aluminium chloride, phosphorus pentachloride and methylammonium chloride react together to give various phosphazenes and phosphazene adducts of aluminium chloride e.g. CI,P-NMe.AICI,. At some ratios of reactants heterocyclic derivatives which appear to contain aluminium are formed.'73 Once formed PNP systems are readily substituted [Cl,P=NPCl,]BCl gives [(SCN),P=NP(NCS),]-[B(NCS),]174" and alkoxy-derivatives e.g. (RO),P(O)NHP(O)(OR) are formed similarly ;' 74b hydrolysis of amino-derivatives of cyclic phosphazenes gives various amidophosphazene esters.' 74c Considerable numbers of studies of the conformations of cyclic phosphazenes continue to appear and structures which present new points include that of N,P,Cl,(NHPr'),,HCl which has a boat-shaped ring with gem-amino-groups and protonation of the ring system at the ring nitrogen between the two P(NHPr') groups ;' 7 5 a hexaphenoxycyclotri-phosphazene [NP(OPh),] which is almost planar with two nitrogens displaced in opposite directions from the plane of the remainder of the atoms the con-formations of the phenoxy-groups are different at each phosphorus ;' 7 5 b I 7 O A.Schmidt Chem. Ber. 1970 103 3923. H. W. Roesky and G. Remmer 2. Naturforsch. 1971 26b 75. 1 7 2 ( a ) G. E. Graves D. W. McKennon and M. Lustig Inorg. Chem. 1971 10 2083; (b) J. S. Harman M. E. McCartney and D.W. A. Sharp J. Chem. Soc. ( A ) 1971, 1547; (c) J. Emsley J. Moore and P. B. Udy ibid. p. 2863; ( d ) H. Binder and E. Fluck, Z. anorg. Chem. 1971 381 21 ; (e) U. Bieller and M. Becke-Goehring ibid. p. 209. H. Vollmer and M. Becke-Goehring 2. anorg. Chem. 197 1,382,28 1 . 1 7 4 ( a ) H. Binder 2. anorg. Chem. 1971,383,279; (b) A. A. Volodin V. V. Kireev G . S. Kolesnikov and S. S. Titov J. Gen. Chem. (U.S.S.R.) 1970 40 2189; V. V. Kireev, G . S. Kolesnikov and S. S. Titov ibid. p. 2002; (c) L. Riesel E. Herrmann H. Patzmann R. Somieski H. Kroschwitz D. Schroter and H.-A. Lehmann Z. Chem., 1970 10 466. 1 7 5 ( a ) N. V. Mani and A. J. Wagner Acra Crysr. 1971 B27 51; (b) W. C. Marsh and J. Trotter J . Chem. Soc. ( A ) 1971 169; (c) W. Harrison R. T. Oakley N.L. Paddock, and J. Trotter Chem. Comm. 1971,357; ( d ) K. W. Muir and J. F. Nixon ibid. p. 1405; ( e ) E. H. M. Ibrahim R. A. Shaw B. C. Smith C. P. Thakur M. Woods G. J. Bullen, J. S. Rutherford P. A. Tucker T. S. Cameron K. D. Howlett and C. K. Prout, Phosphorus 1971 1 153 The Typical Elements 327 nitrilocyclotriphosphazene which has the structure (74) with weak central bonds, one of which is broken by dimethylamine which also converts all P-C1 bonds into c12 P N / \N c1\ I I,C1 / p \ / p \ N N N I I I C W \ P /PC12 N / I \N c1 (74) PNMe groups.' 75c The structure of 1,3-(di-t-butyl)-2,4-dichlorodiazadiphosphe-tidene (75) establishes that the ring is slightly puckered ;' 75d cis-(76) has a puckered ring but the corresponding trans-isomer is planar ; the reason for the difference is probably the close approach between phenyl groups that would be present in a planar cis-isomer.17" (75) (76) (77) The cyclic di-imides (77) are formed when phosphonic diamides are heated. ' 76u Boron trifluoride has been shown to be a fluorinating agent for (MeNPCl,),, substituting two axial fluorines to give (MeNPFCI,) .' 766 Phosphadiazetidones e.g. (78) are formed when NN'-bis(trimethylsily1)ureas react with phosphorus fluorides. ' 76c The five-membered ring 1,3-diaza-2-phospholidines (79) have been n Me N / \ O=C ,PF,-,R RNkp,NR N R' (78) (79) prepared by amination of dichlorophosphines with substituted ethylenediamines ; PhBCl and AsCl replace phosphorus with boron or arsenic,' 77u and all of these ring compounds readily undergo ring expansion by insertion of e.g.CS into a P-N bond. ' 7 7 b Substituted cyclophosphazenes have been prepared by direct Me 1 7 6 (a) P. M. Zavlin V. A. Zamora and A. S. Fedoseeva J . Gen. Chem. (U.S.S.R.) 1971, 41 473; (b) H. Binder Z . anorg. Chem. 1971 384 193; (c) R. E. Dunmur and R . Schmutzler J . Chem. Soc. ( A ) 1971 1289. 1 7 7 (a) M. K. Das and J. J. Zuckermann Inorg. Chem. 1971 10 1028; (b) M. K. Das, P. G. Harrison and J. J. Zuckermann ibid. p. 1092 328 D . W . A . Sharp M . G . H. Wallbridge and J. H. Holloway methods MePCl and Me,PCl react with ammonium chloride or ammonia to give (NPClMe),, and (NPMe,),, ,' 7 8 a whereas (C,F,),PCl gives [NP(C,-F7),],, ;' 78b by cyclizing the optically active salt [Ph(NH,)(p-Tol)PNP(p-To1)-(NH,)Ph]Cl with PCl the first optically active cyclophosphazene (80) has been a 2 (80) formed.' 7 8 c Groups which have been substituted directly on to phosphorus atoms of (NP) ring systems include B10H13,179a C2Ph,179b C2H3 Me,'69c9d Ph,179e imidazolidine groups (from ethylenediamines),' 79f OR ' 79c and SR.179c If P-NSO derivatives are reacted with oxalyl chloride isocyanates e.g.N,P,F,-NCO are formed and these may be converted into carbonyl derivatives or into compounds such as N,P,F,N=C(NH,)Me. ' 79g Many dihydroxyaromatics react with (NPCl,) derivatives to give spirophosphazenes but catechol and base react with (NPCI,) to give the phosphorane (81) the difference from the trimer probably being attributable to the effects of ring Syntheses of various other ring systems related to phosphazenes have been described.Examples include (ring atoms only) NP'NCNC NPVNPVNC,180" NPVNPVNSV1,' 80b and N P ~ N P ~ N P ~ O P ~ . ~ ~ OC 1 7 ' ( a ) F. A. Cotton and A. Shaver Znorg. Chem. 1971 10 2362; V. N. Prons M. P. Grinblat and A. L. Klebanskii J . Gen. Chem. (U.S.S.R.) 1971 41 475; (b) ibid., 1970 40 2108; (c) C. D. Schmulbach C. Derderian 0 Zeck and S. Sahuri Znorg. Chem. 1971,10 195. 1 7 9 ( a ) N. T. Kuznetsov and G. S. Klimchuk Russ. J . Inorg. Chem. 1970 15 1495; ( 6 ) T. Chivers Inorg. Nuclear Chem. Letters 1971 7 827; ( c ) E. Niecke H. Thamm, and 0. Glemser Z . Naturforsch. 197 1,26b 366 ; ( d ) N. L. Paddock T. N . Ranganathan, and S. M. Todd Canad. J . Chem. 1971,49 164; ( e ) M. Biddlestone and R. A. Shaw, J .Chem. SOC. ( A ) 1971,2715; (fj! T. Chivers and R. Hedgeland Inorg. Nuclear Chem. Letters 1971 7 767; (8) H. W. Roesky and E. Janssen Z . Naturforsch. 1971 26b, 679; ( h ) H. R. Allcock and E. J. Walsh Znorg. Chem. 1971 10 1643. ( a ) A. Schmidpeter and C. Weingard Angew. Chem. Internat. Edn. 1971 10 397; ( 6 ) U. Bieller and M. Becke-Goehring 2. anorg. Chem. 1971 380 314; (c) A. Schmidpeter and K. Stoll Angew. Chem. Znrernar. Edn. 1971 10 131 The Typical Elements 329 Oxidation of P406 in carbon tetrachloride gives P,07 (82) as well as the mixed phase P407-P408. l 8 Polyphosphoric acids and their ammonium salts which are of great importance as fertilizers have been reviewed. Several interesting structures of phosphates have been reported. Hypophosphoric acid dihydrate has the structure (H30)2[(HO)0,P~P0,(OH)] :182b Na2H,P,06 ,H,O and Na,H,P,O ,6H,O have very similar unit-cell dimensions and the same space group; however the POP bond in the latter is not linear but has an angle of 136" ;IB2' sodium phosphonoformate Na3[03PC0,],6H,0 has the structure indicated by the formula ; the P-C bond is long probably because of repulsion between negative charges.' 82d N.m.r.evidence suggests that some ultraphos-phates M,O:P,O < 1.0 have comparatively small ions probably with simple cage structures such as (83).' 83 Sodium tris[ethyleneglycolato(2 -)]phosphate, 0 NaP(OCH,CH,O) the first aliphatic six-co-ordinate phosphorus compound, is formed from EtP(OCH,CH,O) ethylene glycol and sodium methoxide.' 84n trans-1,2-Dichloroethylene reacts with PCl and 0 to give Cl,P(O)-O-CHClCHCl in a direct reaction.'84b Perfluoroalkoxyfluorophosphoranes, e.g.t-C4F90PF4 are formed by chlorine elimination from perfluoroalkyl-hypochlorites and chlorofluorophosphoranes. ' 5u Dioxabenzofluorophospholes, e.g. (84) may be prepared from siloxanes when bulky groups are attached to the ' ' I D. Heinz H. Rienitz and D. Radeck 2. anorg. Chem. 1971 383 120. (a) L. V. Kubasova Russ. Chem. Rev. 1971 1 ; (6) D. Mootz and H. Altenburg Acta Cryst. 1971 B27 1520; (c) R. L. Collin and M. Willis ibid. p. 291; ( d ) R. R. Naqvi, P. J. Wheatley and E. Foresti-Serantoni J. Chem. SOC. ( A ) 1971 2751. T. Glonek T. C. Meyers P. Z. Han and J. R. Van Wazer J. Amer. Chem. SOC. 1970, 92 7214. 1 8 4 (a) B. C. Chang D.B. Denney R. L. Powell and D. W. White Chem. Comm. 1971, 1070; (b) C. B. C. Boyce and S. B. Webb J. Chem. SOC. (0 1971 1613. (a) D. E. Young and W. B. Fox Inorg. Nuclear Chem. Letters 1971 7 1033; (6) M. Eisenhut and R. Schmutzler Chem. Comm. 1971 1452 330 D . W. A . Sharp M . G . H. Wallbridge and J. H. Holloway aromatic ring;185b they also result from fluorination of the corresponding chloride with boron trifluoride. 176b \ I R-P~TO I F F (84) Measured differences between the binding energies in PCl and P(O)Cl have been discussed in terms of the nature of the P-0 bonds;lE6" a large number of complexes formed by P(O)Br and P(S)Br have been described; the bonding is from 0 or S to the metal.'86b A large number of phosphorus-containing free radicals e.g.POCl,- PO,F- and PCl, are also known.ls7 Much chemistry of difluorophosphine oxide F,POPF is now known. With amines and alcohols species of the types [NR,H,] [HFPO,] HFPO,R and PF,HO are formed ; the latter gives salts containing the [HFPOJ ion with amines or aminophos-phines. 188 Nitrosonium difluorophosphate NOP0,F2 is formed when nitrosyl chloride reacts with free HPO,F ;lS9" the hydrolysis of the P0,F2-and P0,F2- ions is strongly catalysed by hard acids such as ThIV Zr" and All11 189h Tw o new dihalogeno-oxophosphorus acids HP0,ClF and HP0,BrF are formed by the action of halogen on the PH bond of H[PH02F].189C The thermal decomposition of PI and P214 in the presence of oxygen gives P,I species as a minor product ; polymeric iodides (PSI3)" are formed when P214 is dissolved in carbon tetrachloride oxidation gives the polymeric species P,120,.'90 Addition of iodine to P4S in solution gives a new form of P&I2 in which a P-P bond in P4S3 has been broken with addition of iodine to each phosph~rus.'~'" The structure of P4Se,I differs from this in the orientation of the ring^."'^ Oxidation of P4Se3 with bromine gives P4Se which has the same cage structure as P4S, that is having one bridging selenium inserted in the basal 1 8 6 1 8 7 1 8 8 1 8 9 190 1 9 1 ( a ) M.Barber J. A. Connor M. F. Guest I. H. Hillier and V. R. Saunders Chern. Comm. 1971 943; cJ A. Serafini J.-F. Labarre A. Veillard and G. Vinot ibid., p. 996; (b) W. Van der Veer and F. Jellinek Rec. Trav. chim. 1970 89 833. A. Begum S. Subramanian and M.C. R. Symons J. Chem. SOC. ( A ) 1971 700; A. Begum and M. C. R. Symons ibid. p. 2065; C . M. L. Kerr and F. Williams J . Phys. Chem. 1971,75 3023. L. F. Centofanti and R. W. Parry Inorg. Chern. 1970 9 2709. ( a ) V. P. Babaeva and V. Y. Rosolovskii Russ. J. Inorg. Chem. 1971,16,471 ; (b) H. R. Clark and M. M. Jones Inorg. Chem. 1971 10 28; (c) H. Falius and K.-P. Giesen, Angew. Chem. Internat. Edn. 1971 10 555. T. Kennedy and R. S. Sinclair J. Inorg. Nuclear Chem. 1970 32 1125; T. Kennedy, J. Thermal Anal. 1970 2 379; M. Baudler P. Junkes and G. Sadri 2. Naturforsch., 197 1 26b 759. ( a ) G . J. Penney and G. M. Sheldrick J. Chem. SOC. ( A ) 1971 1100; G. W. Hunt and A. W. Cordes Inorg. Chem. 1971 10 1935; (b) G. J. Penney and G. M. Sheldrick, Acra Cryst.1970 B26 2092; (c) J . Chern. SOC. ( A ) 1971 245 The Typical Elements 331 P unit of P,S and a terminal selenium added to an adjacent pho~phorus.'~'' U.V. irradiation of 00'-dialkyldithiophosphate glasses gives (RO),PS radicals. ' 92 Phosphorus chloridetetrafluoride PC1F4 may be readily prepared by the action of C1F on PF .193a The adducts PCI ,NbCl, PCl ,TaCI PCl,Br,BCl, and PCl,BrF,PF all contain halogenophosphonium ions PCI,+ or PCl,Br+. 193b Arsenic.-As with many other metalloids arsenic forms coloured solutions containing cations AS,^ + and As, + when oxidized with peroxydisulphuryl difluoride in acidic media.'94 Studies of the vibrational spectrum of tetra-methyldiarsine Me,AsAsMe show that there are two isomers probably the cis- and trans- present in the liquid and only the trans-form in the solid.195a Trifluoromethylarsenic tetramer (AsCF,) has a non-planar central ring of four arsenic atoms.195b Mass spectrometric studies of the heterocyclic species (85) show that R is readily lost to give stable arsenium cations. 196 Aminoarsines ( 8 5 ) X = 0 or NMe Y = O o r S result from aminolysis reactions with arsenic chlorides dimethylaminoarsines, or alkoxy-derivatives. Complex polycyclic derivatives are easily formed. ' 7 a Lactones and epoxides undergo ring-opening with aminoarsines ; the arsenic remains co-ordinated to oxygen. 197b Dimethylarsenic azide Me,AsN is formed as a liquid from the iodide and silver azide; dimethylbismuth azide is a solid 198a chlorine azide oxidizes PhAsC1 to PhAsCl,N which decomposes thermally to trimeric NAsClPh which is probably similar to a cyclophospha-zene.198b Bis(trifluoromethy1)nitroxy-derivatives of trifluoromethylarsenic e.g. (CF,),NOAs(CF,) are formed from (CF,),As and (CF,),N0.'99 The structures of Me,AsCl and Me,AsBr show some evidence for weak halogen bridging between the trigonal-bipyrimidal molecules it is significant that the n.m.r. spectrum of tribenzylarsenic difluoride (benzyl) AsF shows 1 9 ' M. Sato M. Yanagita Y. Fujita andT. Kwan Bull. Chem. SOC. Japan 1971,44 1423. 1 9 3 ( a ) W. B. Fox D . E. Young R. Foester and K. Cohn Znorg. Nuclear Chem. Letters, 1971 7 861; (b) H. Preiss 2. anorg. Chem. 1971 380 56; F. F. Bentley A. Finch, P. N. Gates and F. J. Ryan Chem. Comm. 1971 860. 1 9 4 R. C. Paul J. K. Puri K.K. Paul R. D. Sharma and K. C. Malhotra Znorg. Nuclear Chem. Letters 1971 7 725. 1 9 5 ( a ) J. R. Durig and J. M. Casper J. Chem. Phys. 1971 55 198; (b) N. Mandel and J. Donohue Acta Cryst. 1971 B27,476. R. H. Anderson and R. H. Cragg Chem. Comm. 1971 1414. (6) J. Koketsu and Y. Ishii J. Chem. SOC. (C) 1971 2. Chem. Znternat. Edn. 1971 10 516. 1 9 ' ( a ) K. Sommer W. Lauder and M. Becke-Goehring Z. anorg. Chem. 1970 379,48; 1 9 8 (a) J. Muller Z. anorg. Chem. 1971 381 103; (b) V. Krieg and J. Weidlein Angew. 99 H. G. Ang and K. F. Ho J. Organometallic Chem. 197 1 27 349. 'O0 ( a ) M. B. Hursthouse and 1. A. Steer J. Organometalfic Chem. 1971,27 C11; (b) C. G. Moreland R. J. Beam C. W. Wooten and S. M. Horner Znorg. Nuclear Chem. Letters, 1971 7 243 332 D .W . A . Sharp M. G. H . Wallbridge and J . H. Holloway evidence for intermolecular fluorine exchange.200b Ureas and sulphamides react with As(NMe,) to form amido-arsenic derivatives e.g. (H,NCO.NH),As or (H,N.SO,-NH),As, which may contain bridging amide groups.201n The co-ordination compound AsC1 ,NMe has a structure derived from a trigonal bipyramid with an equatorial lone pair but the nitrogen is surprisingly in an axial position as in SbCl,,NPhH,.20'b The absolute configuration of a tris-chelated arsenic derivative ( -),,,-triscatecholatoarsenate(v) has been established by X-ray and c.d. methods.202 Piperidine reacts with realgar As,S, to give (piperidinium),As,S ; the anion (86) has an open basket structure corresponding (86) to the replacement of an As-As bond of As,S by two terminal As-S units.203 Arsenic trifluoride reacts with silylamines and siloxanes to give substituted derivatives e.g.As,(NMe),F and (E~O),ASF.~~~' It has now been shown that arsenic pentafluoride dissolves in anhydrous hydrogen fluoride to form the As,F - ion and tetra-alkylammonium salts of this species can be isolated.204b Crystalline AsCl,F has the structure [AsCl,] [ASF,] ;205a the AsCl,' ion is also found together with SbC1,- and pyramidal AsCl units in the adduct AsCl ,C1 ,SbCl ,AsCl .205b Antimony.-The vibrational spectrum of pentakiscyclopropylantimony [pre-pared from cyclopropyl-lithium and tris(cyc1o-propy1)antimony dibromide] is consistent with a square-pyramidal co-ordination about antimony.206a Bis-(dichlorostibino)methane (C1,Sb),CH2 is formed from (Ph,Sb),CH and hydrogen chloridg;206b it may be useful in the preparation of co-ordinating bistibines.The lower limit to the barrier to inversion in stibines has been established at 26 kcal mol- in agreement with the fair stability of optically active stibines.206' Organoantimony pseudohalides (azides isocyanates and iso-thiocyanates) result from interaction of the halide and the appropriate silver salt.207 Many adducts formed between diorganoantimony trichlorides and ligands such as dimethyl sulphoxide have been described ; it is considered that 201 ( a ) K. Sommer and W. Laver 2. anorg. Chem. 1970 378 310; ( 6 ) M. Webster and 2 0 2 T. Ito Inorg. Nuclear Chem. Letters 1971 7 1097. '03 E. J . Porter and G. M. Sheldrick J. Chem. SOC. ( A ) 1971 3130.2 0 4 ( a ) R. J. Singer M. Eisenhut and R. Schmutzler J . Fluorine Chem. 1970/1 1 193; (b) P. A. W. Dean R. J. Gillespie R. Hulme and D. A. Humphreys J . Chem. SOC. ( A ) , 1971 341. S. Keats J . Chem. SOC. ( A ) 1971 836. 2 o s ( a ) H. Preiss Z . anorg. Chem. 1971 380 45; ibid. p. 71. 206 ( a ) A. H. Cowley J. L. Mills T. M. Loehr and T. V. Long J. Amer. Chem. Sac., 1971 93 2150; (b) Y. Matsumura and R. Okawara Inorg. Nuclear Chem. Letters, 1971 7 113; (c) J. Jacobus Chem. Comm. 1971 1058. 2 0 7 R. G. Goel and D . R. Ridley Inorg. Nuclear Chem. Letters 1971,7 21 The Typical Elements 333 they are six-co-ordinate species with oxygen-antimony bonds.208a Triorgano-antimony thioglycollates and glycollates R,SbXCH2CO0 (X = 0 or S ) are formed from the dialkoxides and free glycollic acids; most are monomeric with chelating glycollates and non-planar R,Sb groups although dimerization through a carboxylate bridge is observed for Me,SbOCH2C00.208b The tetraphenyl derivatives of phosphorus and arsenic Ph4MX are four-co-ordinate in the solid state as is Ph,SbClO, but other tetraphenylantimony derivatives appear to be molecular in the solid208' [trigonal-bipyramidal co-ordination is considered the likely geometry in spite of the fact that many antimony(v) com-pounds are now known to have square-pyramidal geometry].All antimony species except Ph4SbF are four-co-ordinate in methanolic solution although the cations could be solvated.208' Tetramethylantimony carboxylates formed from pentamethylantimony and the carboxylic acid form adducts Me4-SbOOCR,HOOCR' with a further molecule of carboxylic acid.It is probable that there is hydrogen-bonding between the acid and carboxylate residues but that the complex anion is chelated to antimony through two oxygens.208d Carbamates ureido and similar derivatives e.g. Sb(O,C.NMe,) are formed by addition of Sb(NMe,) to double bonds.208e Tetramethylantimony thiolates, Me,SbSR are only stable below room temperature and are formed as covalent liquids when Me,Sb reacts with thiols; at higher temperatures they decompose to Me,Sb and RSSR but methylantimony dithiolates MeSb(SR) are formed from Me,SbCl and RSH at low temperature^.^" Tris(triethylgermy1)stibine asso-ciates under the influence of heat light or catalysts. lo Hydrazoic acid and sodium azide eventually give (SbCl,N,) with antimony pentachloride ; in 1 1 proportions sodium azide gives NaSbCl,N .' ' 2 1 Sb Mossbauer studies on some complex oxides including pyrochlores suggest that up to 25 % of the antimony is present as Sb"' a result of importance in the understanding of the geometry and bonding in this type of Heating mixtures of SbF and Sb20 gives various forms of SbOF ; L-SbOF has four-co-ordinate antimony with a vacant site for the lone pair of electrons cor-responding to an equatorial position in a trigonal-bi~yramid.~ 3a SbC1,OMe is a dimer with octahedral antimonys linked by two methoxy-bridges.,' 3b Molecular oxygen-bonded adducts of SbCl and BiC1 with phosphine and arsine and SbF and AsF with oxy-compounds such as S0,Cl,2'4b ' 0 8 ( a ) N.Nishii Y . Matsumura and R. Okawara J . Organornetallic Chern. 1971 30, 59; (b) Y . Matsumura M. Shindo and R. Okawara ibid. 1971 27 357; (c) J. B. Orenberg M. D. Morris and T. V. Long Znorg. Chern. 1971 10 933; ( d ) H. Schmidbaur and K.-H. Mitschke Angew. Chern. Znternat. Edn. 1971 10 136; ( e ) J. Koketsu and Y . Ishii J . Chern. SOC. (C) 1971 5 11. '09 H. Schmidbaur and K.-H. Mitschke Chern. Bet-. 1971 104 1837 1842. ' l o Y . A. Alexandrov G. A. Razuvaev and G. N . Figurova J . Organometallic Chern., 'I1 A. Schmidt 2. anorg. Chem. 1971,381 31. ' 1 2 L. H. Bowen P. E. Garrou and G. G. Long J . Inorg. Nuclear Chern. 1971 33,953. ' I 3 (a) A . h t r o m and S. Anderson Acta Chem. Scand. 1971 25 1519; (b) H. Preiss, 'I4 ( a ) S . Milicev and D.HadZi Inorg. Nuclear Chern. Letters 1971 7 745; (b) J. Bacon, 1971 27 207. Z . anorg. Chem. 1971 380 65. P. A . W. Dean and R. J. Gillespie Canad. J . Chern. 1971 49 1276 3 34 D . W . A . Sharp M . G . H . Wallbridge and J . H. Holloway have been described. Ionization to antimony-containing cations occurs at higher temperatures in the latter systems. Antimony pentafluoride forms the [SbF,OOCCF,]- ion in trifluoroacetic acid.',' The [Sb(C,O,),l3- ion in its potassium and ammonium salts has a pentagonal-bipyramidal structure with the antimony lone pair stereochemically active.2 ' Molecular SbF can be isolated as a pyramidal molecule in matrices; large cations e.g. tetra-alkylammonium ions give salts containing SbF,- ions the anion appearing to have the C, symmetry expected for a species with a lone pair of electrons derived from a trigonal-bipyramid ;2 16' SbF,- ions weakly associated by fluorine bridges to pyramidal SbF molecules are also present in KSb2F,,216b which does not contain Sb,F,- ions as reported for CsSb,F,.Considerable progress has been made towards an understanding of the antimony pentafluoride system. In the solid state SbF is a tetramer with bridging fluorines between antimony atoms. The structure has a close-packed arrangement of fluorines but at a molecular level is different from that of other pentafluorides in that there are two different Sb-F-Sb bond angles.21 Spectroscopic studies indicate at least dimers in liquid and gaseous SbF .217b Fluxional MF4Sb,F5,+ molecules with fluorine bridging are considered present in MF,-SbF,-S0,ClF (M = Nb or Ta) mixtures.21 7c (PyH),Sb"'Sb~Br, and (quinuclidinium),-Sb"'SbVBr ,2Br contain Sb"'Br6 and SbVBr6 units but with close Br-Br contacts.218a Vibrational studies on solutions containing SbX, - and T ~ x ~ -(X = C1 Br or I) show great deviations from the behaviour expected for octa-hedral species in agreement with a stereochemical effect for the lone pair of electrons.2 *' The mixed halogenoantimonate(v) anions [SbCl,F,] - (from SbC1,- and HF)218c and [SbCl,Br]- (from SbC1 and Br-)2'8d have been reported.Bismuth.-The Bi+ ion has been little characterized previously but has been shown to be present in the compound (Bi+)(Bi95+)(HfC162-)3,219a and also in the gaseous monomer BiAIC1 . ' 9b Bismuth triarenesulphinates Bi(O,SR) , are easily prepared from bismuth acetate and the free sulphinic acid.The arenesulphinites decompose smoothly to triarylbismuthines in a useful prepara-tive reaction.220 Triphenylbismuth salts of dibasic oxyacids e.g. Ph,BiCO, seem 'I5 M. C. Poore and D. R. Russell Chem. Comm. 1971 18. * I 6 ( a ) C. J. Adams and A. J. Downs J . Chem. SOC. ( A ) 1971 1534; ( 6 ) S. H. Mastin and R. R. Ryan Znorg. Chem. 1971 10 1757. 2 1 7 ( a ) A. J. Edwards and P. Taylor Chem. Comm. 1971 1376; ( 6 ) L. E. Alexander, Znorg. Nuclear Chem. Letters 1970 7 1053; E. W. Lawless Znorg. Chem. 1971 10, 2084; (c) P. A. W. Dean and R. J. Gillespie Canad. J . Chem. 1971,49 1736. 2 1 8 ( a ) S. L. Lawton R. A. Jacobson and R. S. Frye Inorg. Chem. 1971 10 701 ; S. L. Lawton and R.A. Jacobson ibid. p. 709; ( b ) C. J. Adams and A. J. Downs Chem. Comm. 1970 1699; ( c ) W. Schmidt D. Steinborn and L. Kolditz Z . Chem. 1970,10, 440; (d) G. Goetz M. Deneux and J. F. Leroy Bull. SOC. chim. France 1971 29. z 1 9 R. M. Friedman and J. D. Corbett Chem. Comm. 1971 422; (b) R. A. Lynde and J. D. Corbett Znorg. Chem. 1971 10 1746. 2 2 0 G. B. Deacon G. D. Fallon and P. W. Felder J . Organometallic Chem. 1971 26, c10 The Typical Elements 335 to have non-ionic polymeric structures containing bridging anions :22 '" the reaction between triphenylbismuth dichloride and AgClO or AgBF in acetone gives acetonyltriphenylbismuthenium salts.22 I b The Bi203-BiF system has been studied in detail and a large number of oxyfluorides characterized.222 Bismuth trichloride forms a 1 1 adduct with DMF solutions in this solvent giving adducts or ~ o l v o l y s i s .~ ~ ~ Bismuth pentafluoride has a chain [BiF,F,,,], with the bismuth atom octahedrally ~ o - o r d i n a t e d . ~ ~ ~ PART 111 Groups VI-VIII 1 GroupVI Oxygen.-Reactions of oxygen atoms with hydrogen various carbon and sulphur compounds ammonia and hydrazine have been reviewed l a and their reaction with H,S has been the subject of detailed investigations.'bvc In an interesting study2 on adsorbed negative ions MgO was irradiated with U.V. light in the presence of hydrogen at 77 K. The oxide turned blue owing to the produc-tion of electrons which occupy surface anion vacancies. When the H was replaced by N20 and the oxide was warmed to 90 K the blue colour faded and simultaneously the e x .spectrum of the electrons was replaced by that of 0-. The existence of 0; in molten LiF-NaF-KF at 773 K has been e~tablished,~" and KCl KBr and KI crystals have been prepared containing enough 0, centres for detailed study of the e.p.r. lines belonging to pairs of exchange-coupled neighbour~.~' The dissociation of 0 by electron impact has been studied.," Electronically excited O2 has been produced by the vacuum-u.v. photolysis of OCC1,,4b and the photoelectron spectrum of 02( 'Ag) has revealed two previously unreported bands which have been tentatively assigned to the 2Ag and 2@u states of O2f.,' A low-temperature gas-phase i.r. spectrum of pure oxygen revealed a doublet which has been assigned to the dimer (02)2 .5 The calculated energy of formation (-2220 f 290 kJ mol- ') is indicative of a van der Waals-type complex.' 2 2 ' ( a ) R.G. Goel and H. S. Prasad Canad. J . Chem. 1971,49,2529; ( 6 ) J . Chem. SOC. ( A ) , 2 2 2 A. Morell B. Tanguy and J. Portier Buff. SOC. chirn. France 1971 2502. 2 2 3 A. K. Mishra and K. N. Tandon Inorg. Chem. 1971 10 1896. 2 2 4 C. Hebecker Z. anorg. Chem. 1971,384 111. 1971 562. ( a ) H. G. Wagner and J. Wolfrum Angew. Chem. Internat. Edn. 1971 10 604; ( 6 ) L. T. Cupitt and G. P. Glass Trans. Faraday SOC. 1970,66 3007; ( c ) S. Takahashi, Mem. Defence Acad. Math. Phys. Chem. Eng. (Yokosuka Japan) 1970 10 369. ( a ) F. L. Whiting U.S. Atomic Energy Commiss. 1970 TID-25480 (Nuclear Sci. Abs. 1970 24 41249); ( b ) R. Baumann and W. Kaenzig J . Phys.(Paris) Colfoq. 1971 (1) ( a ) R. S. Freund J . Chem. Phys. 1971,54,3125; ( b ) H. Okabe A. H. Laufer and J. J. Ball ibid. 1971 55 373; ( c ) N. Jonathan A. Morris K. J. Ross and D. J. Smith, ibid. 1971 54 4954. ' C. Naccache Chern. Phys. Letters 1971 11 323. (Pt. l) C1-226-C1-227. ' C . A. Long and G . E. Ewing Chern. Phys. Letters 1971 9 225 336 D . W. A . Sharp M. G . H . Wallbridge and J . H. Holloway The electrochemical synthesis of concentrated ozone appears to be more favourable in NaCIO than in electrolytes containing HClO and H,S04.6 The quantum yield of 0 formation from the photolysis of 0 at 1849 and 1931 8, has been obtained,' and interesting flash-photolysis studies of 0 have been made.8",b A new r.m.s. value (0.5324 k 0.0024debye) for the dipole moment of ozone has been obtained from measurements of the Stark effect.' Reactions of 0 in the stratosphere have been briefly reviewed,"" and reactions with atomic hydrogen at low pressure,'0b and with NO, HPOS- and SeOi- in solution'0c have been studied.The ozonide ion (0;) has been detected by e.s.r. spectroscopy during anodic evolution of oxygen in concentrated KOH at low temperature. ' ' Properties of water have been briefly reviewed.12" It has been shown that a number of physical properties ( X ) can be expressed (even at high temperatures) by an equation In X = A + B/T - To (where T = temperature To = 155 K, and A and B are constants).12' Heat capacities of water measured in a flow calorimeter deviate significantly from data derived from various equations of state (including the internationally accepted one).. H bond receives special attention in a short review on aspects of hydrogen-bond theory by Huggins (who first introduced the hydrogen-bond ~oncept).'~" Hydrogen bonding in the water dimer has been studied within the SCF-MO-LCAO framework.' 3 b Of the three configurations that have been proposed for dimeric water (open chain bifurcated and cyclic) the open-chain structure now seems correct on the basis of high-resolution i.r. work with a solid matrix.'," Although free rotation of the acceptor molecule [H(I)O(l)H;l)] around the hydrogen bond [O(,,H( 1)0(1)] axis was first assumed,'4b recent theoretical calculations predict a value in the 5.02-9.64 kJ mol- for the internal potential barrier of the dimer. Because the presence of dimers in water vapour affects thermodynamic calculations the thermodynamic properties of water dimer have been evaluated on the basis of this m0de1.l~' MO calculations, however also support the open-chain configuration.' The linear dimer is The 0 ' G.F. Potapova and A. A. Rakov Efektrokhimiya 1971,7 537. ' N. Washida Y. Mori and I. Tanaka J . Chem. Phys. 1971,54 1 1 19. ( a ) V. D. Baiamonte L. G. Hartshorn and E. J. Blair J . Chem. Phys. 1971 55 3617; ( 6 ) R. Gilpin H. I. Schiff and K. H. Welge ibid. p. 1087. M. Lichtenstein J. J. Gallagher and S. A. Clough J . Mof. Spectroscopy 1971,40 10. l o ( a ) M. Nicolet Ann. Ceophys. 1970 26 531 ; ( 6 ) P. E. Charters R. G. Macdonald, and J. C. Polanyi Appl. Optics 1971 10 1747; (c) V. A. Lunenok-Burmakina and T.M. Franchuk Ukrain. khim. Zhur. 1970,36 1020. l 1 C. L. Gardner and E. J. Casey Canad. J. Chem. 1971,49 1782. * ( a ) R. A. Horne 'Kirk-Othmer Encyclopaedia of Chemical Technology' Interscience, New York 1970 2nd edn. p. 668; (see also M. W. Skougstad ibid. p. 688); ( b ) 0. Singh and N . Dass Indian J . Pure Appl. Phys. 1971 9 92; ( c ) A. M. Sirota A. Ya. Girshkov and A. G. Tomishko Tepfoenergetika 1970 17 60. l 3 ( a ) M. L. Huggins Angew. Chem. Internat. Edn. 1971,10 147; ( b ) G. H. F. Diercksen, Theor. Chim. Acta 1971 21 335. l 4 ( a ) A. J . Tursi and E. R. Nixon J . Chem. Phys. 1970,52 1521 ; ( b ) K. Morokuma and L. Pedersen ibid. 1968 50 3275; (c) J. Delbene and J . A. Pople ibid. 1970 52 4858; ( d ) P. A. Kollman and L. C. Allen ibid.p. 5085; ( e ) J. Chao R. C. Wilhoit and B. J. Zwolinski J . Chem. Thermodyn. 1971 3 195. l 5 (a) C. N . R. Rao A. Goel and A. S. N . Murthy Indian J . Chem. 1971 9 56; ( b ) C. N. R. Rao A. Goel and A. S. N. Murthy J . Chem. SOC. ( A ) 1971 190 The Typical Elements 337 more stable than either the bifurcated or the cyclic dimer' 5a and the linear dimers are more stable when the 0-H vector is not directed towards the lone-pair orbital of the donor 0 atom.lSb 1.r. investigations of water16" and 1 1 water : acceptor molecule complexes' 6b in CCl solutions however have been inter-preted as indicative of both cyclic'6" and open'6b water dimer structures, respectively. A good linear relationship between the symmetric and asymmetric OH stretching frequencies was established in the latter study,'6b and a similar result was obtained for those hydrates in which the water molecules are symmetric-ally bonded to anions.'6c In the lower atmosphere finite amounts of vapour-phase water dimers may be responsible for absorptions at 7-11 17 22 and 28 cm- ' which cannot be attributed to monomeric water vapour." The subject of water structure continues to provide controversy.1.r. and Raman spectroscopic techniques are being widely applied to the problem the effects of varying temperature ' pressure,' *' solute ' 8c*d or solvent' 8 e ~ S have been investigated. The vacant-lattice-point model has been used to rationalize many properties of aqueous solutions. 19a-g Theoretical and quasi-theoretical studies have been prevalent and important new work on 'hydrophobic inter-Although the concept of structure in water has not been defined absolutely, it may be taken to mean that as water becomes more structured the extent of intermolecular bonding increases.If the high mobility of protons in H,O is due to the well-known 'proton-jump mechanism' then structure breaking should result in a lowering of proton mobility. Experimental work on the hydrogen ion and the cadmium ion does not support this conclusion and suggests that a normal ionic diffusion process is more significant.20" In another interesting study the classical equations of motion were solved for 216 molecules of water in a computer simulation of liquid water. The conclusions reached were that the liquid structure is a highly strained and random H-bonded network with little resemblance to known water structures in water-containing crystals and that has provided a new view of water structure.' l 6 ( a ) L. B. Magnusson J . Phys. Chem. 1970,74,4221; ( b ) P. Saumagne J . Chem. Phys., 1970 53 3768; (c) L. J. Bellamy M. J. Blandamer M. C. R. Symons and D. Waddington Trans. Faraday SOC. 1971 67 3435. H. A. Gebbie R. A. Bohlander and G. W. F. Pardoe Nature 1971 230 521. ( a ) H. F. Fisher W. C. McCabee and S. Subramanian J. Phys. Chem. 1970 74, 4360; ( b ) J. T. Bell and N. A. Krohn ibid. p. 4006; ( c ) G. E. Walrafen J . Chem. Phys., 1971 55 768; ( d ) A. P. Zhukovskii and A. I. Sidorova Strukt. Rol Vody Zhivom Organizme 1970 3 99 ( e ) W. A. P. Luck and W. Ditter J. Phys. Chem. 1970 74, 3687; (A D. N .Glew and N . S. Rath Cunad. J . Chem. 1971,49,837. l 9 ( a ) 0. D. Bonner Rec. Chem. Progr. 1971 32 1; ( b ) V. V. Puchkov and L. D. Kislovskii Strukt. Rol Vody Zhivom Organizme 1970 3 45; (c) I. Z. Fisher ibid., p. 34; (dl K. Arakawa and K. Sasaki Bull. Chem. SOC. Japan 1970 43 3048; ( e ) M. E. Pollack J . Macromol. Sci. 1971 5 737; cf) Yu. V. Gurikov Zhur. strukt. Khim, 1971 12 208; ( g ) Yu. P. Syrnikov Strukt. Rol Vody Zhivom Organizme 1970 3 50; (h) A. Ben-Naim and F. H. Stillinger in 'Structure and Transport Processes in Water and Aqueous Solution' ed. R. A. Horne Wiley New York 1971 ; (i) A. Ben-Naim, J. Chem. Phys. 1971 54 1387; ( j ) ibid. p. 3696. 2 o (a> N. K. Roberts and H. L. Northey J . Chem. SUC. ( A ) 1971,2572; ( 6 ) A. Rahman and F. H. Stillinger J .Chem. Phys. 1971,55 3336. l 338 D . W . A . Sharp M . G . H. Wallbridge and J. H. Holloway diffusion is the result of co-operative interaction with many near neighbours and does not occur in discrete hops.20b In ion-molecule reactions in the Oi-H,O system H30+ OH and H30+ H,O are produced.2'" When ions are produced in electrical discharges in the presence of trace quantities of H 2 0 and SO, the mobilities of the ions produced are less than those expected for simple ions owing to the formation of heavier clusters, e.g. H,O+(H,O)(SO,) and (02+)(S0,),.21b The i.r. spectra for HX,xH,O (X = C1 or Br; x = 1 4 ) and evidence for the existence of HC1,4H20 have been reported.22" The spectra of the dihydrates have been interpreted"' in terms of a very strong central H-bond in H,O; in accord with earlier crystallographic results.Theoretical studies on H,O; indicate that an LCAO-MO-SCF wavefunction adequately represents the geometry energy-form and spectroscopic properties of such strong H-bonds.2zb A book has appeared on equilibrium sorption and diffusion of water in polymers.23 Factors affecting the shape and intensity of n.m.r. lines of H,O on such things as zeolites silica gel and clay minerals have been reviewedz4" and the orientation symmetry of water molecules in some fibrous structures has been determined by n.m.r. methods.24b During 1970 disquieting observations were reported2 which gave credence to the view that 'anomalous water might be an artifact due to such spurious effects as dissolution of glass quartz or other uninteresting contaminants'.26 This year even more evidence of this kind has accumulated.Dielectric measurements, though unlike those obtained with liquid water bore a marked resemblance to those obtained with adsorbed ~ a t e r . ~ ' " The validity of some earlier spectroscopic work has been questioned,27b and the incompatibility of data from i.r. spectra with those from vapour pressure and viscosity measurements have been stressed.27c Mass spectrometric analysis gave only peaks corresponding to m/e equal to 17 and 18 and some solid remained.27b Material with similar properties to 2 1 ( a ) F. C. Fehsenfield M. Mosesman and E. E. Fergusson J . Chem. Phys. 1971 5 5 , 2115; (6) A. W. Castleman jun. I. N. Tang and H . R. Munkelwitz Science 1971, 173 1025.2 2 ( a ) A. S . Gilbert and N. Sheppard Chem. Comm. 1971 337; (6) P. A. Kollman and L. C. Allen J . Amer. Chem. Soc. 1970 92 6101. 2 3 J. A. Barrie in 'Diffusion Polymerization' ed. J. Clark Academic Press London, 1968 p. 259. 2 4 ( a ) V. I . Kvlividse Suyazannaya Voda Dispersnykh Sist. 1970,41; (b) A. A. Khanagov, Kristallografiya 1970 15 732. 2 5 D. W. A. Sharp M. G. H. Wallbridge and J. H. Holloway Ann. Reports ( A ) 1970, 67 317. 2 6 W. Drost-Hansen Ind. and Eng. Chem. 1969 61 10. " ( a ) P. Hoekstra G. Swinzow S. Ackley and W. T. Doyle Nature Phys. Sci. 1971, 229,92; (6) B. A. Pethica W. K. Thompson and W. T. Pike ibid. p. 21 ; (c) F. Menes, J . Chim. phys. 1970,67,2059; (d) W. A. Adams M. K. Gabe P. G. Manning S. H. Whitlow J. D. Kingham and B.F. Scott Nature Phys. Sci. 1971 230 39; ( e ) R. E. Davis D . L. Rousseau and R. D. Board Science 1971 171 167; (f) M. DePaz, A. Pozzo and M. E. Vallauri Chem. Phys. Letters 1970,7,23; ( g ) W. D. Bascom E. J . Brooks and B. N. Worthington Nature 1970 228 1290; (h) B. F. Howell and J. Lancaster Chem. Comm. 1971 693; (i) W. M. Madigosky Science 1971 172 264; (j) R. G. Gardiner W. W. Mansfield and R. I. Willing Austral. J . Chem. 1971 24, 681 The Typical Elements 339 ‘anomalous’ water was prepared in ‘Vycor’ glass but it had a high silica content and the authors suggested that it may be silicic acid solution.27d Evidence from e.s.c.a. experiments showed the presence of Na’ K+ SO:- C1- NO, BOZ-, SiOi- and C-0 in polywater samples. Earlier report^^^^^^ also provide evidence for silicon-containing constituents and it has been pointed out that the properties observed can be exhibited by mixtures of SiO, H20, and Na,0.27h Other reports indicate that the i.r.spectrum resembles that of N ~ O A C ~ ~ ’ and that other properties resemble those of short-chain carboxylates and Several p a p e r ~ ~ ~ ~ ~ * j ~ ~ ~ v ~ h ave examined the extent to which the observed properties of anomalous water are compatible with those of H 2 0 containing impurities leached from the walls of the apparatus. Concerning theoretical models for anomalous water it has been suggested29” that of the symmetric H-bonded structural models previously proposed only is satisfactory in terms of known stereochemistry. Even that model, however has such a low energy barrier for the conversion of symmetric H-bonds to ordinary asymmetric ones that transformation to ordinary water must In spite of the doubts yet more new forms of polywater have been reported,30aJ and a ‘high-yield’ method of preparation has been claimed.31 An intriguing critical review of the ‘anomalous water’ phenomenon has appeared32 and a host of others have also been p ~ b l i s h e d .~ ~ ” - ~ Studies on the properties of liquids in narrow capillaries have Rotational barriers in H202 have been investigated using LC (Hartree-Fock) AO-MO-SCF methods3’ and an investigation of the reactions of H202 with acetone has been initiated.36 Hypofluorous acid HOF has been synthesized3 and experimental conditions for the efficient synthesis of F203 have been studied.38 Production of OF 2 8 ( a ) P.Barnes I. Cherry J. L. Finney and S. Petersen Nature 1971,230,31; (b) W. W. 2 9 ( a ) B. Kamb Science 1971 172 231 ; (b) L. C. Allen and P. A. Kollman ibid. 1970, 3 0 ( a ) J . Middlehurst and L. R. Fisher Nature 1970 227 57; ( b ) J. Middlehurst and 3 1 S. B. Brummer G. Entine J. I. Bradspies H. Lingertat and C. Leung J . Phys. Chem., 3 2 H. S. Rossotti J . Inorg. Nuclear Chem. 1971 33 2037. 3 3 ( a ) H. Chojnacki Wiadomosci Cherni. 1970 24 677; (b) J. B. Hasted Contemp. Phys., 1971 12 133; ( c ) M. Ito Kotai Butsuri 1970 5 533; (d) T. S. Kim Kongyon Rebyu, 1970 12 (3) 3 ; ( e ) I. Kosa-Somogyui Atomtech-Tajek 1970 13 392; (f) H. Krauss, Naturwiss. Rundschau 1970 23 417; (8) W. W. Mansfield Search 1970 1 332; (h) J. T.G . Overbeek Koninkl. Ned. Akad Wetenschap. Verslag Gewone Vergader. Afdel. Nut. 1970 79 144; ( i ) G. Peschel and K. H. Adlfinger Mitt. deut. pharm. Ges., 1971,304,29; ( j ) M. Smutek Chem. Listy 1971,65,374; ( k ) S . Suzuki and M. Aizawa, Farumashia 1971,7 19. 34 ( a ) K. Leinfelder Surface Sci. 1970 23 427; ( 6 ) M. A. Frommer M. Shporer E. Loebel and R. Bloch U.S. Clearinghouse Fed. Sci. Tech. Inform. AD 1970 No. 713 731 (U.S. Gout. Res. Develop. Reports 1970 70 (66); ( c ) W. J. O’Brien Surface Sci. 1971, 25 298. Mansfield Austral. J . Chem. 1971 24 675. 167 1443. L. R. Fisher ibid. 1971 230 575. 1971,75,2976. 35 R. B. Davidson and L. C. Allen J . Chem. Phys. 1971,55 519. 3 6 M. C. V. Sauer and J. 0. Edwards J . Phys. Chem. 1971,75 3004. 3 7 M. H.Studier and E. H. Appleman J . Amer. Chem. Soc. 1971,93 2349. j8 K. Meier and D . Genthe Deut. Luft-Raumfahrt Forschungber 1970 DLR FB 70(55) 340 D . W . A . Sharp M . G . H. Wallbridge and J . H . HolIoway radicals by the reaction of F atoms with 0 has been described3'" and OF and LiOF have been detected by matrix-isolation spectroscopy.39b The i.r. and Raman spectra of solid 02F2 and the i.r. spectrum of matrix-isolated 02F2 have also been ~bserved.~' The use of OF for chain extension of polyperfluoro-polyenes insertion of functional groups in the polymer structure and addition copolymerization with perfluorodienes has been de~cribed,~ l a and the thrust-chamber technology for OF2-B2H propellants has been reviewed.41b Raman measurements on liquid OF have confirmed literature i.r.assignments and support the existence of Fermi resonance between v1 and v2.42a The valence ionization potentials of F20 have been determined by photoelectron spectroscopy.42b Sulphur.-A comprehensive book which stresses developing areas rather than well-established ones in sulphur chemistry has appeared.43 More studies which are concerned in some way with 3d orbital participation in the bonding in a variety of sulphur compounds have been For SF and other second-row-element compounds the 3d orbitals have been shown to be contracted in the presence of electronegative ligand~.~' Analysis of effective potential functions for the 3d orbitals in sulphur and oxygen indicate a possible origin for the non-expansion of the octet amongst first-row atoms.46 New results of spectro-scopic mean amplitudes and force constants for s6 have been obtained4' and more reports of the cations S4+,49a4 Sl,49d-g and s1+6,49a have appeared.Hitherto only one organic polysulphide has been detected in nature but during the year bis-(3-oxoundecyl)trisulphide and bis-(3-oxoundecyl)tetrasulphide were The radical S T has been detected by e.s.r. 3 9 ( a ) H. G. Wagner J. Warnatz and C. Zetzsch Angew. Chem. Internat. Edn. 1971 10, 40 J. J. Turner D. J. Gardiner and N. J. Lawrence J. Chem. SOC. (A) 1971,400. 4 1 ( a ) M. S . Toy J. Polymer Sci. Part A-I Polymer Chem. 1971 9 217; (b) R. W. Riebling and W. B. Powell J. Spacecraft Rockets 1971,8 4 . 4 2 ( a ) D. J. Gardiner and J. J. Turner J. Mol. Spectroscopy 1971 38 428; (b) A. B. Cornford D.C. Frost F. G. Herring and C. A. Dowell J. Chem. Phys. 1971 55, 2820. 4 3 'Sulphur in Organic and Inorganic Chemistry' ed. A. Senning Marcel Dekker Inc., New York 1971 (3 vols). 44 ( a ) I. A. Hillier and V. R. Saunders Chem. Comm. 1970 1183; (b) G. L. Bendazzoli, P. Palmieri B. Cadioli and U. Pincelli Mol. Phys. 1970 19 865; ( c ) W. F. Cooper, N. C. Kenny J. W. Edmonds A. Nagel F. Wudl and P. Coppens Chem. Comm., 1971,889; ( d ) B. Roos and P. Siegbahn Theor. Chim. Acta 1971,21 368; ( e ) Y. Ozias and L. Reynard ibid. 1971 20 51 ; (f) R. Keat D. S. Ross and D. W. A. Sharp, Spectrochim. Acta 1971 27A 2219. 564; (b) L. Andrews and J. I. Raymond J. Chem. Phys. 1971,55 3078. 4 5 R. G. A. R. Maclagan J. Chem. SOC. ( A ) 1971,222. 4 6 R. F. Stewart and B.C. Webster J. Chem. SOC. (A) 1971 2987. 4 7 ( a ) D. Behar and R. W. Fessenden J. Phys. Chem. 1971,75,2752; (6) R. 0. C. Norman 4 8 S. J. Cyvin Z. anorg. Chem. 1970 378 117. 49 ( a ) R. J. Gillespie J. Passmore P. K. Ummat and 0. C. Vaidya Znorg. Chem. 1971, 10 1327; (b) R. A. Beaudet and P. J. Stephens Chem. Comm. 1971 1083; ( c ) R. C. Paul J. K. Puri and K. C. Malhotra Inorg. Nuclear Chem. Letters 1971 7 729; ( d ) F. Seel V. Hartmann I. Molnar R. Budenz and W. Gombler Angew. Chem. Internat. Edn. 1971 10 186; ( e ) M. Stillings M. C. R. Symons and J. G. Wilkinson, J. Chem. SOC. ( A ) 1971,3201 ; (f) M. Stillings M. C. R. Symons and J. G. Wilkinson, Chem. Comm. 1971 372; ( g ) R. C. Paul V. P. Kapila J. K. Puri and K. C. Malhotra, J. Chem. SOC. ( A ) 1971,2132.and P. M. Storey J. Chem. SOC. (B) 1971 1009 The Typical Elements 34 1 isolated from algae.50 Polyatomic sulphur chains have also been obtained”“ in hexathia[3,3]cyclophanes [(87) (88) and (89)] and as bridges between C-3 and s-s-s Q-Js-s-sn s-s-s a 0 s-s-s Hexathia[3,3]orthocyclophane Hexathia[3,3]metacyclophane (87) (88) s-s-s I s-s-s Hexathia[3,3]paracyclophane (89) C-6 in 2,5-piperazinediones (90).5’b A tetrameric sulphide chain has also been found in benzylidenimine tetrasulphide (9 1) by X-ray structure determinati~n.~ Five different structures have been attributed to the compound which can be n Me I H 0 x;x I Me (90) (91) prepared by the reaction of benzylamine with tetrasulphur tetranitride,’ I d sulphur monochloride or trisulphur dichloride’ le or from the decomposition of benzylamine disulphide5 le or N-benzylhepta~ulphurimide.~ A new trialkyl derivative of the S,N ring and two new bicyclic nitrogen sulphides S1,N2 (92) s-s-s s-s-s \ S / \ / \ /N\s / s \ /N\ / S s-s-s s-s-s (92) R.E. Moore Chem. Comm. 1971 1168. 5 1 ( a ) F. Feher K. Glinka and F. Malcharek Angew. Chem. Internat. Edn. 1971 10, 413; ( b ) H. Poise1 and U. Schmidt ibid. p. 130; ( c ) J. C. Barrick C. Calvo and F. P. Olsen Chem. Comm. 1971 1043 ( d ) Y . Sasaki and F. P. Olsen Cunad. J . Chem., 1971 49 271 ; (e) Y. Sasaki and F. P. Olsen ibid. p. 283; (f) B. A. Olsen and F. P. Olsen Inorg. Chem. 1969 8 1736; (g) H. Garcia-Fernandez H. G. Heal and M. S. Shahid Compt. rend. 1971 272 C 60; (h) L. Niinisto Suornen Kemi (B) 1970 43, 342; (i) M.Schmidt and E. Wilhelm 2. Nuturforsch. 1970 25b 1348; ( j ) J. Nelson, Spectrochim. Acta 197 1 27A 1 105 342 D . W. A . Sharp M . G . H. Wallbridge and J . H. Holloway and SI9N (93) have been ~ynthesized.''~ S,NH and S6(NH) are amongst the main products when S2C1 reacts with aqueous and the reaction of S2C12 with H,Se gives Se,S6 and Se,S in a 1 2 ratio.'l' The Raman spectra of heptasulphurimide and three hexasulphurdi-imides in the solid state have been reported and compared with i.r. spectra in the solid state and in s~Iution.~'j The possibility of an S . - - H - S type hydrogen bond in the H,S dimerS2' and of strong hydrogen bonding of the S-H-S type in the H,S-HS- adductS2' have been studied theoretically. The Raman spectrum of H2S as guest in a P-quinol clathrate has been reported.' The reactions of H2S with FSSF, SSF, SF, and SOF254n produced in each case one or more sulphanes, H,S,.The absolute rate of reaction of atomic hydrogen with H2S has been measured,54b and a mechanism has been proposed for the reaction of H,S with SO which involves mono- and poly-atomic sulphur species.54c S4N2 and S4N are amongst the main products of reaction of S2Cl2 with NH .'lh An improved X-ray powder-diffraction pattern of S,N has been obtained" and new S,N complexes with SbCl, SeCl, TeCl, and BCl and their adducts with SO have been prepared.56 Tetrathiotetraimide (SNH) , forms 1 1 adducts with AlCl and AlBr but gives (S4N4)2 ,SnBr with SnBr,. Chlorine and bromine cause ring contraction to give (NSCl) and S,N,Br, re~pectively.,~ The reaction of 100% H2S04 with S4N4 produces SO,, sulphamic acid HSO; S,O<- NH; and an unidentified cation amongst the stable products.58a Ammonolysis of S4N4 gives S,O;- SO;- SO:-, and H2NS0,.58b The sulphur monoxide molecule SO has been detected in the electrodeless discharge of inert-gas-SO and in the gas-phase pyrolysis of N -sulphin ylaniline.' 9b 5 2 ( a ) J.R. Sabin J . Amer. Chem. SOC. 1971 93 3613; (b) J. R. Sabin J . Chem. Phys., 5 3 J. E. Davies Chem. Comm. 1971,270. 5 4 ( a ) B. Meyer T. V. Oommen B. Gotthardt and T. R. Hooper Znorg. Chem. 1971, 10 1632; (b) M. J. Kurylo N. C. Peterson and W. Braun J. Chem. Phys. 1971 54, 943; ( c ) N. P. Volynskii Zhur. neorg. Khim. 1971 16 301. " S. Hamada A.Takanashi and T. Shirai Bull. Chem. Soc. Japan 1971,44 1433. 5 6 R. C. Paul C. L. Arora J. Kishore and K. C. Malhotra Austral. J . Chem. 1971 24, 1637. s ' A. J. Banister and D. Younger J . Znorg. Nuclear Chem. 1970 32 3763. 5 8 ( a ) W. L. Jolly and S. A. Lipp Znorg. Chem. 1971 10 33; (b) Mu-Chang Shieh K. 5 9 ( a ) N. Jonathan D. J. Smith and K. J. Ross Chem. Phys. Letters 1971 9 217; 1971,54,4675. Katabe and T. Okabe Bull. Chem. SOC. Japan 1970,43 3449. (b) S. Saito and C. Wentrup Helv. Chim. Acta 1971 54 273 The Typical Elements 343 A short document has appeared on liquid SO as a reaction medium.60 The Raman spectrum of SO guest in a P-quinol clathrate has been obtained5 and force constants have been calculated from the i.r. spectrum of S1802 .61a Solvent interactions with dissolved SO have been studied for a variety of solvents at room temperature by Raman spectroscopy.6 I b Clusters of SO molecules about oxonium and NO ions have been detected in electrical discharges where traces of H 2 0 and SO are present21b and molecular associations of 2SO,-SO (probably linear and ionic) and S02-2S0 (possibly cyclic and non-ionic) were deduced from measurements of liquid-vapour equilibria densities dielectric constants electrical conductivities and Raman spectra of SO,-SO solutions.62a The formation of complexes between SO, and halide ions have been studied by two laboratories.62b,' The standard enthalpies of formation point to weak association of the charge-transfer type.62b Sulphur dioxide insertions into palladi~m-oxygen~~" and iron-(o-allyl) bonds have been reported.63b Despite the familiarity of SO; to the e.s.r.spectroscopist, only recently has anything been learned about its vibrational or electronic spectrum. Both studies are agreed that it has C, symmetry and an OSO angle of ca. 1 lW.64a,b The S - 0 force constant is significantly lower than that in SO ,64a consistent with the extra unpaired electron being in an antibonding molecular orbital between the sulphur and two ~ x y g e n s . ~ ~ ~ . ~ A short book concerned with inorganic addition compounds of SO has been published.65 Raman spectra of binary liquid mixtures show that complexes of SO are formed with (MeO),SO, HO(Me)SO, and Me(MeO)SO, but not with Cl,P0.66a Ionic formulations have been proposed for complexes of SO with S,N456 and the 1 1 complexes formed with SeCl, TeCl, PCl, Ph,CCI, Bu,NCl and thiotrithiazyl chloride and fluoride.66b ICl,(SO,Cl) and I(SO,Cl), are formed with ICl,66b,c and iodine monochlorosulphate is the product of the reaction of SO with IC1.66c This latter compound disproportionates in highly acidic media to give iodine compounds of both lower and higher oxidation states.66c In a study of the systems H,O-SO,-I,O (n = 3-5) several already well-known I,O ,SO complexes have been prepared and it has been shown that 6 o L.F. Audrieth 'Liquid Sulphur Dioxide A Novel Reaction Medium' Stauffer Chemical Co. New York 1969. b 1 ( a ) A. Barbe and P. Jouve J. Mol. Spectroscopy 1971,38 273; ( 6 ) Y. Le Duff and R. Ouillon Compt. rend. 1971 272 B 757. 6 2 ( a ) Y.De Mauduit and G. H. Weinreich J. Chim. phys. 1971,68,267; see also Compt. rend. 1970 271 C 1420; ( b ) S . Wasif A. Salama S. B. Salama and M. Sobeir J. Chem. SOC. ( A ) 1971 11 12; (c) T. H. Norris and E. J. Woodhouse Znorg. Chem., 1971 10 614. 63 ( a ) M. Graziani R. Ros and G. Carturan J. Organornetallic Chem. 1971 27 C19; ( b ) M. R. Churchill and J. Wormald Znorg. Chem. 1971 10 572. 6 4 ( a ) D. E. Milligan and M. E. Jacox J. Chem. Phys. 1971 55 1003; ( b ) A. Reuveni, Z . Luz and B. L. Silver ibid. 1970 53 4619. '' T. Hoehle 'Constitution of Some Inorganic Addition Compounds of Nitrosyl Chloride and Sulphur Trioxide' Joko Amsterdam 1970. 6 6 ( a ) G. H. Weinreich and Y. De Mauduit Rev. Chim. minirule 1970 7 747; ( 6 ) R. C. Paul C. L. Arora and K.C. Malhotra Indian J. Chem. 1971 9 473; (c) R. C. Paul, C. L. Arora and K. C. Malhotra J. Znorg. Nuclear Chem. 1971,33 991 ; ( d ) K. Selte and A. Kjekshus Acta Chem. Scand. 1971,25 751 344 D . W. A . Sharp M . G . H . Wallbridge and J. H. Holloway I,O (at 398-523 K) decomposes irreversibly into 120 and I through the intermediate 1203,S03.66d SO reacts with M2S208 (M = K or Ph,As) in a 1 2 ratio in CH,Cl to give M,S,O, containing the monoperoxotetrasulphate Raman spectroscopic methods have been used to examine the bisulphate-sulphate systems in detail.68"yb Current-efficiency correlations for peroxydi-sulphate formation in solutions of H2S04 K,SO, and (NH,),SO with the actual SO;- concentration have shown that SO; - ions exclusively are involved in the peroxodisulphate f ~ r m a t i o n .~ ~ The rate equation for the oxidation of iodine to iodate by S 2 0 i - in aqueous solution is -d[I,]/dt = k,[S20i-]*-[I2I3 + kB[S20i -1 [12]3.70 The new substance S2O8(CIO4) perchloryl peroxy-disulphate is formed amongst the products of electrolysis of 6M-H2SO,-3N-Absorption bands believed to be due to the SF radical have been detected in the absorption spectrum of the product from the reaction of COS and F The U.V. spectra of the isomers SSF and FSSF were measured and band maxima were obtained for the unstable compound FSSCl ; the band contours show that, on irradiation with light photolytic processes convert SSF into FSSF which is then decomposed to SF, S2F4 SF, and Vibrational spectroscopic studies have been carried out on S2C1 and S2Br .7 2 c 9 d Chemical analysis n.m.r. and mass spectrometric examination of the yellow oil produced in low yield from the reaction of sulphur with AgF show that it is a mixture of difluoropolysulphanes (S2F2 S3F2 and S,F,).73 Both SSF and FSSF in fluorosulphonic acid and 30 % oleum give the (now familiar) polysulphur cations.49d SSF reacts with BF at low temperatures to give [S,F]+[BF,]-; the conversion of SSF into FSSF being catalysed by BF,. Combination of AsF with S,F takes place below 173 K to give [S2F]+[AsF6]- which at 373 K with excess of AsF gives SF AsF and S,[AsF6] (or S,[ASF6]).49d S2C1 and SCl (and their selenium analogues) react with disulphuric acid to give the elements and SCl,.49g S,C12 forms complexes with SbCl and BCl, in liquid SO, and stable complexes (S,Cl ,2base) are also formed with organic tertiary bases.In all cases the complexes have been shown to be ionic.740 Solid complexes of S,Br2 and SCl with DMF AcNHMe AcNMe, AcNEt, pyridine, p- and y-picolines quinoline isoquinoline and piperidine have been made and the relative shifts in the absorption frequencies on complex formation suggest that SCl is the stronger acceptor.74b ~ c 1 0 . 7 1 67 B. Bressel and A. Blaschette Z . anorg. Chem. 1970 377 162. 6 8 ( a ) H. Chen and D. E. Irish J . Phys. Chem. 1971,75 2672; (b) ibid. p. 2681. 6 9 W. Smit and J . G . Hoogland Electrochim. Acta 1971 16 1 . 7 0 F. Secco and S. Celsi J . Chem. SOC. ( A ) 1971 1092. ' l A. A. Rakov G. F. Potapova and V. I. Veselovski Elektrokhimiya 1970 6 1730. 72 ( a ) G.Di Lonardo and A. Trornbetti Trans. Faraday SOC. 1970 66 2694; (b) F. Seel and K. P. Wanczek 2. Phys. Chem. (Frankfurt) 1970 70 109; ( c ) C. A. Frenzel and K. E. Blick J . Chem. Phys. 1971 55 2715; ( d ) E. B. Bradley Kyoto Univ. Off. Res. Eng. Serv. Bull. 1971 No. 95. 73 F. Seel R. Budenz W. Gombler and H. Seitter Z . anorg. Chem. 1971 380 262. 7 4 (a) R. C. Paul J. Kishore D. Singh and K. C. Malhotra Indian J . Chem. 1970 8, 829; (6) R. C. Paul S. K. Gupta and S. L. Chadha ibid. 1970 8 1020 The Typical Elements 345 Shock-tube studies of SF dissociation have been made at 1650-1950 K and rate constants for the initial fragmentation of SF4 were determined.75" The charge distribution about SF has been discussed in detail in the light of molecular quadrupole moment determinations from the combination of molecular g values and magnetic susceptibility anisotropies with moments of inertia.75b Solid adducts of PF, BF, AsF, and SbF have been obtained with CF,SF3 and their i.r.spectra have been interpreted to show that they should be formulated as [CF3SF2]+[MF,+J- (where MF is the a~ceptor).~ The SF ion has been shown to have a tetragonal-pyramidal structure in the salts Cs'SFS and [Me,N] + [SF,] - .77 The effect of SF as a specific scavenger for e in the photolysis of aqueous solutions of halide or SCN- ions has been ~tudied.~'" Independent indicate that the electron affinity of SF is in the region 0.43-1.47eV. It has been shown that SF reacts with BF SiF, PF, and PF oia fluoride-ion transfer.78d Force constants for SF6 have been obtained from isotopic sub-s t i t u t i ~ n .~ ~ ' ~ ~ Information on SF is included in a review on reactivity and thermal stabilities of hexafluorides"" and a shorter article on vapour pressure and sublimation pressure data.80b Sulphur hexafluoride has been produced from sulphide minerals by direct combination with F at high pressures1' and by reaction with BrF3;*lb it has also been made by electrolysis of KHF,-HF-S mixtures.' A review on fluorides and oxofluorides of sulphur has been published with emphasis on oxofluorides and the work of Cady and his colleagues in par-ticular.s2" Raman and i.r. data have shown that the compound formed by the reaction of OSF and 2C1F,AsF5 should be formulated [OSClF,]+ [ASF6]-.82b The reactions of SOCl with sulphates and disulphates have been closely studied.82'*d Since SO,F is a principal product of the oxidation of SF there has been renewed interest in the decomposition kinetics of sulphuryl difluoride itself.s3 The reaction of SF,OF with NO in nickel and aluminium vessels gave SOF and ONOF (which could be isomerized to FNO at 423 K).Nitryl fluoride, 7 s ( a ) J . F. Bott J . Chem. Phys. 1971 54 181 ; ( 6 ) R. G. Stone H. L. Tigelaar and 7 6 L. C. Duncan and M. Kramar Znorg. Chem. 1971,10 647. 7 7 L. F. Drullinger and J. E. Griffiths Spectrochim. Acta 1971,27A 1793. 7 8 ( a ) R. C. Rumfeldt Canad. J . Chem. 1971 49 1262; ( 6 ) P. R. Hammond J . Chem. Phys. 1971 55 3468; (c) F. C. Fehsenfeld ibid. 1971 54 438; (d) J . G. Dillard and T. C. Rhyne fnorg. Chern. 1971,10 730.79 ( a ) S. N. Thakur J . Mof. Structure 1971,7 315; (b) V. D . Klimov and E. A. Lobikov, Optika i Spektroskopiya 1971,30 48. (a) N. P. Galkin and Yu. N. Tumanov Uspekhi Khim. 1971 40 276; (b) C. E. Hamrin jun. and J. K. Shou J . Chem. and Eng. Data 1971 16 37. ( a ) J. Pezdic and J. Slivnik Vestnik Slouensk. kem. Drustua 1970,17,29; ( b ) H. Puchelt, B. R. Sabels and T. C. Hoering Geochim. Cosmochim. Acta 1971 35 625; (c) H. Ukihashi Y . Oda and M. Suhara G.P. 2 033 109/1971. 8 2 ( a ) G . H. Cady fntra-Sci. Chem. Reports 1971 5 1 ; ( b ) C. Lan and J. Passmore, Chem. Comm. 1971 950; ( c ) Y. Auger M. Wartel and J. Huebel Bull. SOC. chirn. France 1970 3455 ; ( d ) Y . Auger M. Wartel and J. Huebel ibid. p. 3462. 83. K. L. Wray and E. V. Feldman J . Chem.Phys. 1971 54 3445. W. H. Flygare ibid. 1970 53 3947 346 D . W . A . Sharp M . G . H . Wallbridge and J. H . Holloway however could not be detected in the reaction product^.'^ For the first time, unit cell parameters and vibrational spectra have been reported for both NOS0,F and NO,SO,F. Although the spectra have been interpreted in terms of ionic compounds containing SO,F- the observed number of vibrational bands does not agree with those expected for an unperturbed anion with C, symmetry.85“ However S03C1- with C, symmetry has been confirmed in the compounds MS0,Cl (M = Li Na K or NH,).8sb Reactions of the chlorodisulphate ion, S,O,Cl- have shown that with 0,- donors the fundamental reaction was S,O,Cl- + 0,- -+ S,O:- + C1- ; with a strong 0,- acceptor in the presence of SO, S,06Cl- can function as a Investigations of solutions of acid halides in disulphuric acid have provided a simple route to determining their ionic nature.86a Cryoscopic and conducti-metric studies of compounds containing S-0 bonds in H,S,07 have shown that dimethyl sulphoxide and alkyl and aryl sulphones and disulphides behave as strong bases whereas diphenyl sulphoxide is sulphonated.86b In a conducti-metric study of various solutes in methanesulphonic acid it has been shown that the order of relative acidity is H2S,07 > HS0,F > HS0,Cl > H2S04 > H,SeO .86c The inorganic chemistry and physical properties of Me,SO have been reviewed in detail” and the crystal structure of Me,SO has been determined by X-ray diffraction.*’ The radicals HOSO MeSO, and BuOSO have been observed by e.s.r.as intermediates in the reactions between hydroperoxides (RO,H R = H Bu or PhCMe) and SO ,890 and X-irradiation of single crystals of PhCH,SO,CH,Ph yields PhCH,SO whereas PhSO,CH,CO,H PhSO,Me and PhS0,Ph all give PhSO .’ 9b The preparation structure and uses of sulphinato-metal complexes have been comprehensively reviewed.” The ability of the RSOi group to behave as a unidentate ligand and as a bidentate ligand either via the two oxygens or via the sulphur and one of the oxygens has been stressed.” The first syntheses of the hitherto unknown 1,3-dithiolane-2,4-diones (94) have been described; these can be polymerized by prolonged heating in the presence of basic catalysts to polythiocarboxylic esters with the elimination of COS? Bis-(2-carboxyphenyl)sulphur dihydroxide dilactone has been synthesized 8 4 A.J. Colussi and H. J. Schumacher J . Inorg. Nuclear Chem. 1971 33 2680. 8 5 ( a ) F. Aubke A. M. Qureshi and H. A. Carter Canad. J . Chem. 1971,49 35; (6) Y. Auger P. Legrand E. Puskaric F. Wallart and S. Noel Spectrochim. Acta 1971, 27A 1351 ; (c) E. Puskaric S. Noel R. De Jaeger and J. Heubel Rev. Chim. minkrule, 1971 8 21. 8 6 (a) R. C. Paul J. K. Puri and K. C. Malhotra J . Chem. SOC. ( A ) 1970 1751; (b) J . Znorg. Nuclear Chem. 1971,33,2459; (c) R. C. Paul K. K. Paul and K. C. Malhotra, J . Chem. Soc. ( A ) 1970,2712. W. L. Reynolds Progr. Znorg. Chem. 1970 12 1 . 8 8 D. A. Langs J. V. Silverton and W. M. Bright Chem. Comm. 1970 1653. 89 ( a ) B. D. Flockhart K.J. Ivin R. C. Pink and B. D . Sharma Chem. Comm. 1971, 339; (6) M. Geoffroy and E. A. C. Lucken J . Chem. Phys. 1971,55 2719. 90 G . Vitzthum and E. Lindner Angew. Chem. Internat. Edn, 1971,10 315. 9 1 H. R. Kricheldorf Angew. Chem. Internat. Edn. 1971 10 726 The Typical Elements 347 as an organosulphur compound containing four-co-ordinate sulphur(1v) Of the two structures possible (95) and (96) both of which resemble the trigonal-bipyramidal form of the SF molecule and the TeIVO group found in some n [O<JO] + nCOS + (-S-CHR-CO)" ' (94) ' tellurites structure (95) seems more likely.92" Perfluoroalkanesulphinic acids, RS(0)OH (R = CF or n-C,F,) containing sulphur(1v) have also been prepared for the first time.92b II 0 (95) (96) Sulphonyl linkages have featured in the oxidation of bis-(4-methylbenzyl) sulphide to bis-(4-methylbenzyl) sulphone and thence to bis-(4-carboxybenzyl) s ~ l p h o n e ~ ~ ~ i.e.and in the preparation of sulphonated polysulphones from poly(ary1 ether sulphones) and ClS0,H or SO in C1CH2CH2C1.93b F o=s I 'OPh F (97) I / F 9 2 ( a ) I. Kapovits and A. Kalman Chem. Comm. 1971 649; (6) H. W. Roesky Angew. 93 ( a ) H. Miiller Angew. Chem. Internat. Edn. 1971 10 652; (6) J. P. Quentin G.P. Chem. Internat. Edn. 1971 10 810. 2 021 833/1970 348 D . W. A . Sharp M . G . H . Wallbridge and J. H . Holloway A trigonal-bipyramidal structure (97) for S-phenoxysulphur oxide trifluoride Crystallographic data for the three known polymorphs of sulphathiazole has been suggested on the basis of I9F n.m.r.data.94 H have been obtained and a three-dimensional structure analysis of one has been ~ompleted.~’ The novel heterocyclic compound 1,l-dimethyl-5-oxo-4,5-dihydro-1,3-dithia(vr)-2,4,6-triazine 3’3-dioxide (98) has been obtained in small yield from the products of reaction between chlorosulphonyl isocyanate and dimethyl sulphone di-imine in the presence of trieth~lamine.~~ (98) N-Alkyl-SS-dialkyl sulphoximides [R‘R2S(0)NR3] have been prepared in high yield by a simple method.97“ This new synthesis has also made it possible to prepare a new class of sulphur ylides (99) by the route shown :97b R2 0 R2 0 y R:O+ BF; \ +/ NaH BF4- - - H S - NaBF - R:O / \ RZ R’ -N/ \CH2 -R3 R’-N CH2-R3 I R4 / \ R’-N C-R3 I I (R’ R2 and R4 = Me or Et; R3 = H or Me) 11’4 H (99) These substances in turn have been a means of preparing silylated sulphur ylides (100) in which ‘silicon-effect’ stabilization of the carbanionic function R2 R1-N’ ‘C-SiMe, I I R4 R3 (100) 9 4 S.P. von Halasz 0. Glemser and M. F. Feser Chem. Ber. 1971 104 1242. 9 5 G. J. Krueger and G . Gafner Acta Cryst. 1971 B27 326. 96 M. Haake Angew. Chem. Internat. Edn. 1971,10 264. ’’ (a) H. Schmidbaur and G. Kammel Chem. Ber. 1971 104 3234; (b) ibid. p. 3241; (c) ibid. p. 3252 The Typical Elements 349 The i.r. and Raman spectra of Me,NSO,F Me2NS0,C1 and the formerly unknown Me,NSO,Br have been recorded and assigned." The reactions of S-phenoxysulphur oxide trifluoride have been used to prepare N-C-N=S(=O)(F)OPh MeN=S(=O)(F)OPh and CF,CON=S(=O)(F)-OPh.94 The preparation of piperidinosulphur trifluoroimide C,H ,NSF, has given rise to several other types of monofluoride [i.e.aminosulphur(1v) mono-fluoride imides] and a new sulphur di-imide,99" whereas the synthesis of piperi-dinosulphur(v1) oxide trifluoride has made way for new aminosulphur(v1) oxide monofluoride i m i d e ~ . ~ ~ ' A new series of sulphur di-imides has been prepared by the reaction of SF with LiN=C(CF,)2.99' The sulphur oxide imide, FSO,N=S=O forms N-fluorosulphonyldichloroamine FSO,NCl, when treated with chlorine monofluoride at room temperat~re.~~" Reaction of BC1, with FSO,N=S=O gives rise to CISO,N=S=O which readily loses SO at room temperature. The ClSO,N=S=NSO,CI so formed reacts with more ClSO,N=S=O to give 3-chloro-l-thia-3,5-dithia(1~)-2,4,6-triazine 1,1,3-tri-The structure of gaseous ClNSO at 203 K shows that the C1 atom has a cis-orientation and is twisted to a 35.5 f 3.5" dihedral angle from the NSO ~ l a n e .' ~ f Complexes of fluorosulphuryl isocyanate with Cs K and Na fluorides have been formulated as salts of fluoroformylfluorosulphurylimide M + [N(SO,F)C-(0)F]-.'oo" The new compound NF2S02CI has been obtained by the photolysis of an N,F,-SO,Cl mixture. loob N-Trimethylsilyliminosulphur oxide difluoride Me,SiN=SOF has been prepared by the reaction of SOF with both [Me,Si],N'o'"*b and [Me,Si],NI.'o'" With HgF, Me,SiN=SOF gives Hg(NSOF,) ,lO1a,' with CsF the polymer [-N=S(O)F],is obtained and with P203F4 the product is F,(0)PN=S(O)F2." lb Hg(NSOF,) reacts with Cl, Br, I, or HC1 at room temperature to give XN=S(O)F (where X = C1 Br I or HCl) and with F at 80K to give small amounts of highly explosive FN=S(O)F .lo '' A new method of preparation of thiazyl fluoride NSF involves the reaction of SF with Ph,P=NH or Ph,P=NSiMe,.'02" The thiazyl cation NS+ has been characterized by Raman spectroscopy in the NSF,MF (M = As or Sb) complexes prepared by the simultaneous addition of NSF and the respective I 98 H.Burger K. Burczyk A. Blaschette and H. Safari Spectrochim. Acta 1971 27A, 1073. 99 (a) S. P. von Halasz and 0. Glemser Chem. Ber. 1971,104 1247; (b) S. P. von Halasz and 0. Glemser ibid. p. 1256; ( c ) R. F. Swindell and J. M. Shreeve Chem. Comm., 1971 1272; (6) H. W. Roesky Angew. Chem. Internat. Edn. 1971 10 265; ( e ) H.W. Roesky ibid. p. 266; (f) H. Oberhammer 2. Naturforsch. 1970 25a 1497. l o o ( a ) J. A. Roderiguez and R. E. Noftle Inorg. Chem. 1971 10 1874; (6) J. M. Shreeve and L. M. Zaborowski ibid. p. 407. l o ' ( a ) K. Seppelt and W. Sundermeyer Angew. Chem. Internat. Edn. 1970 9 905; (6) 0. Glemser H. Saran and R. Mews Chem. Ber. 1971 104 696; (c) K. Seppelt and W. Sundermeyer Z . Naturforsch. 1971 26b 65. lo* ( a ) R. Appel and E. Lassman Chem. Ber. 1971 104 2246; (6) 0. Glemser and W. Koch Angew. Chem. Internat. Edn. 1971 10 127 350 D . W . A . Sharp M . G . H . Wallbridge and J . H. Holloway pentafluoride to a quartz vessel at room temperature.' 02' X-Ray crystallographic investigation of phenylsulphanuric fluoride shows structure (101). '03 (101) The first compound containing S-N single double and triple bonds, N-(nitridofluorosu1phur)sulphur imide difluoride has been made by the reaction of F I Me,SiN=S=NSiMe, I F with SF at 293 K.'04 Selenium and Tellurium-Books concerned with tellurium and the tellurides' 05a and the chemistry and technology of selenium and tellurium'05b have appeared recently.Selenium and tellurium chemistry is also covered to some extent in a new book on sulphur chemistry.,, The heat of scission of Se-Se bonds (121 13 kJ mol-') has been obtained in an e.s.r. study of the polymerization of liquid selenium.'06 There has been continued interest in polyatomic ions of selenium and tel-l u r i ~ m . ' ~ ~ ~ " The ion Se,' occurs in Se,S,O,, Se,S3010 and Se4S207, which are formed when Se is oxidized by SO in tetra- tri- and di-sulphuric acids respe~tively.'~~" A detailed X-ray structure of Se;' (A1C1;)2 has shown that the Sei' ions have a novel geometry (102).'07' The red colour associated with cold H2S04 or HS0,F solutions of tellurium have been shown to be due to Te:' and the red compounds Te,(Sb,F 1)2 Te,(SO,F), and Te,(AsF,) also contain Te:'.The yellow compounds TeS0,F and TeSbF contain another cation which is now thought to be Tet' whereas Te,AsF is believed to contain Tei I o 3 D. E. Arrington T. Moeller and I. C. Paul J. Chem. SOC. ( A ) 1970 2627. I o 4 0. Glemser and R. Hofer Angew. Chem. Internat. Edn. 1971 10 815. l o 5 (a) D. M. Chizhikov and V. P. Schastlivyi 'Tellurium and the Tellurides' Collets, London 1970; (b) 'Chemistry and Technology of Se Te and Rare Alkali Metals' (Khimiya i Tekhnologiya Selena Tellura i Redkikh Shchelochnykh Metallov) ed.E. A. Buketov Nauka i Alma-Ata U.S.S.R. 1969. l o 6 D. C. Koningsberger J. H. M. C. Van Wolput and P. C. U. Rieter Chem. Phys. Letters 1971 8 145. l o ' (a) R. C. Paul C. L. Arora R. N. Virmani and K. C. Malhotra Indian J. Chem., 1971 9 368; (b) R. K. McMullan D. J. Prince and J. D. Corbett Inorg. Chem., 1971 10 1749; (c) R. Gillespie J. Barr G. P. Pez P. K. Ummat and 0. C. Vaidya, ibid. p. 362 The Typical Elements 35 1 Structural investigations include an electron diffraction study of dimethyl selenide which has been found to assume a stable skew conformation with dihedral angle 87.5 4°,10ga and X-ray crystallographic examinations of KSe(SeCN) ,-0.5H,0,108b [SeC(NH,),] ,C1 ,log' and Te(S20,Ph) 108d have been reported.2 . 3 1 Y Y Perspective views of the Se,' + ion (102) Analysis of i.r. n.m.r. e.s.r. and electronic spectra of bis(diethy1dithiocarbamato)-selenium(I1) indicate that the dtc ligands are unidentate and the S-Se-S unit is bent.'''= Vapour pressures at different temperatures,' 09"+ heat of fusion and heat capacity,logb and thermal ~tability'~~' of SeO have been obtained. Physical properties of TeO single crystals have been reviewed'"" and two crystal modifications have been described.' lob 1.r. and Raman spectra of crystalline SeO ' ' lo and matrix-isolation Raman spectroscopic data for SeO monomer, dimer and higher polymers have been obtained.' ' l b v c The dimer (SeO,) has the trans-centrosymmetric double-oxygen-bridged structure.' 'b,c SeO; SeO,, and SeO radicals have been detected in the y-radiolysis of Ba Ca and Be selenates.' l 2 Reaction of SeO with benzene and its derivatives mainly gives rise to arylselenonic acids (RSeO,H R = Ph p-CIC,H, p-BrC6H4 or p-MeC,H,) with small amounts of selenic acid and diary1 selenones R,SeO .' l 3 l o ' ( a ) P.D'Antonio C . George A. L. Lowrey and J . Karle J. Chem. Phys. 1971 55, 1071 ; ( b ) S. Hauge Acta Chem. Scand. 1971,25 1135; ( c ) A. Chiesi Villa M. Nardelli, and M. E. Vidoni Tani Acta Cryst. 1970 B26 1504; ( d ) K. Ase Acta Chem. Scand., 1971 25 838; (e) G. S. Nikolov N. lordanov and K. Daskalova Inorg. Nuclear Chem. Letters 1970 6 723. l o g ( a ) V. N. Makatun and V.V. Pechkovskii Zhur. j i z . Khim. 1970 44 2667; ( b ) A. S. Pashinkin B. M. Aron S . S. Bakeeva E. A. Buketov N. V. Karyakin G. P. Krylova, K. G. Rustembekov and M. Z. Ugorets ibid. 1971 45 1599; (c) V. I. Sonin and 0. G. Polyachenok Vesti Akad. Navuk Belarusk. S.S.R. Ser. khim. Navuk 1971 121. ' l o ( a ) N. Uchida Kotai Butsuri 1970 5 335; ( b ) S. A. Malyutin K. K. Samplavskaya, and M. Kh. Karapet'yants Zhur. neorg. Khim. 1971 16 1475. "' (a) I. R. Beattie N . Cheetham T. R. Gilson K. M. Livingston and D. J. Reynolds, J. Chem. Soc. ( A ) 1971 1910; ( b ) D. Boal G. Briggs H. Hiiber G. A. Ozin E. A. Robinson and A. Vander Voet Nature Phys. Sci. 1971 231 174; ( c ) Chem. Comm., 1971,686. V. I. Spitsyn A. S. Medvedev V. V. Gromov and V. F. Shtan'ko Doklady Akad.Nauk S.S.S.R 1970 195 643. K. Dostal Z. Zak and M. Cernik Chern. Ber. 1971 104 2044. ' l 352 D . W . A . Sharp M . G . H . Wallbridge and J . H. Holloway The formation of Se2+ in the first step of the reaction is important in the forma-tion of complexes in the reaction of selenous acid with thiosalicyclic acid, 2-mercaptobenzothiazole or 2-aminothiophenol.' The equilibrium constants of the complexes RSSeSR have been determined' 14' and acid dissociation constants of H,TeO have been obtained.' 14b The thermodynamics of the protonation of tungstotellurous heteropolyacids have also been investigated.' 14' The crystal structure of telluric acid shows that it contains discrete Te(OH), octahedra each of the molecules being firmly interconnected by 12 hydrogen bonds.' 15' Chemical effects of the 12%Te + '29Te isometric transition and the ' ,*Te(n,y)' 29Te nuclear reaction have been studied by Mossbauer spectroscopy in telluric acid and in related tellurium-oxygen compounds.' ' 5b Te,Br and Te,C1 have been prepared by reaction of the elements in a tempera-ture gradient and crystallographic data have been obtained.' ' Absorption spectra attributed to SeBr,' ' 7' TeCl and TeBr,' ' 7 b and TeI' have been observed following the flash photolysis of Se,Br, TeC1 TeBr, and TeI respectively. TeCl has also been observed as a condensed phase in the Te-TeC1 system."* Raman studies of Se,C1 and Se,Br (pure and in solution) suggest C and C,, (rather than C previously reported) symmetries respectively.' l 9 In a study of the behaviour of selenium and tellurium chlorides in S,Cl it has been found that TeC1 reacts with S2C1 to give TeCl and sulphur.'20 The SeC1, molecule is stabilized as the tetramethylthiourea complex and it has been suggested that it may be an important intermediate in the decomposition of alkylselenium trihalides.2 2 Using available i.r. and Raman data a vibrational assignment and normal-co-ordinate analysis of SeF has been carried The i.r. and Raman spectra of solid TeCl and SeC1 have been interpreted in detail'23b with the help of the X-ray analysis of solid TeCl published last year.123c Raman data for TeCl,Br are consistent with a low symmetry (C,) structure but not the expected C, structure.' 24a9b The stereochemistry of Te" complexes has been reviewed. ' ( a ) B.W. Budesinsky and J. Svec J . Inorg. Nuclear Chem. 1971 33 3795; ( b ) E. Sh. Ganelina and V. A. Borgoyakov Zhur. neorg. Khim. 1971,16,596; ( c ) E. Sh. Ganelina and V. A. Borgoyakov ibid. p. 214. 'I5 ( a ) 0. Lindqvist Acta Chem. Scand. 1970,24,3178; ( b ) J. L. Warren C. H. W. Jones, and P. Vasudev J . Phys. Chem. 1971,75,2867. A. Rabenau H. Rau and H. Rosenstein Angew. Chem. internat. Edn. 1970 9 802. ( a ) G. A. Oldershaw and K. Robinson Trans. Faraday SOC. 1971,67 907; ( 6 ) J . Mol. Spectroscopy 1971 37 3 14. S. A. Ivashin and E. S. Petrov Izvest. Sibirsk. Otdel. Akad. Nauk S.S.S.R. Ser. khim. Nauk 1970 5 48. ' I 9 W. Kiefer Spectrochim. Acta 1971 27A 1285. l Z o N. S. Fortunatov N. Timoshchenko and Z . A. Fokina Ukrain. khim. Zhur. 1971, 37 6.12' 0. Foss Pure Appl. Chem. 1970,24 31. 1 2 2 K. J. Wynne and P. S. Pearson Chem. Comm. 1971 293. 1 2 3 ( a ) K. Ramaswamy and S. Jayaraman Indian J . Pure Appl. Phys. 1970,8,625; ( 6 ) R. Ponsionen and D. J. Stufkens Rec. Trav. chim. 1971 90 521; (c) D. W. A. Sharp, M. G. H. Wallbridge and J. H. Holloway Ann. Reports ( A ) 1970 67 328. 124 ( a ) G. A. Ozin and A. Vander Voet Chem. Comm. 1970 1489; ( 6 ) Canad. J . Chem., 1971 49 704 The Typical Elements 353 Physical properties of TeC1 in the liquid and vapour have been obtained12'" and properties of the eutectic systems SeCl,-MCl (M = Bi''' Sb'" or MoV) have been st~died.'~'' The adducts TeCI, POC13,126a TeC1,,2C,H4 TeCl,,-C,H and TeCI ,2C3H,' 26'*c have been prepared and space-group and unit-cell parameters were obtained for the latter three.'26c The TeC1 ,C,H crystal contains polymer chains in which the Te atom is five-co-ordinate.'26' New vibrational-spectroscopic data on TeF 1 2 7 have also added to the sparse data on five-co-ordinate anionic species containing SeIV and Te".The discovery of a new synthetic route to five- and six-co-ordinate mixed halide ions of Te" has yielded complexes containing [TeC1,Br3] - and [TeC1,Br,12 - .' 24' Vibrational spectra for solid (Et,N) [TeCl,Br,] favours a stereochemistry based on a square pyramid and for (Et,N),[TeCI,Br,] the presence of a cis-octahedral anion with C, symmetry is SeC1 and TeC1 give Sea and TeC1; when dissolved in disulphuric acid4'g and ionic monochlorosulphates result from their 1 1 combination with The vibrational spectra of Me,SeF and its deuterium analogue are compatible with a molecular geometry of C, symmetry.'28a 'H n.m.r.studies on R,SeF, (R = Me Et or Pr') and 19F studies on PriSeF suggest that the rate-determining step for the fluorine-exchange process is mainly heterolytic Se-F bond breaking ( i t . R,SeF j R,SeF+ + F-) in contrast with SF and SeF where exchange seems to occur mainly via a second-order associative mechanism.'28b The formulation (RMCl,)' (SbCl,)- where M = Se or Te has been ascribed to a series of 1 1 adducts of organo-selenium and -tellurium trichlorides with SbCl, on the basis of the solid-state i.r. spectra.'28c A potentiometric study of chloro-acid/chloro-base systems (e.g. Ba2 +/BaCl, or Fe3+/FeC13) has been carried out in SeOCl as solvent and a pC1- scale has been established.12' Vapour-pressure relationships for SeF and TeF along with other hexa-fluorides have been studied."' The splitting of the C-band ('Alg+ 'T1J in the electronic absorption spectrum of TeCli- is linearly dependent on tempera-ture,','" which seems to confirm the assumption that the splitting of the electronic absorption bands in MX; - ions (M = Se or Te ; X = C1 or Br) can be explained by the dynamic Jahn-Teller effect in the excited states of the complex ions.'30' ' ( a ) L. A. Nisel'son V. P. Borisova and K. V. Tret'yakova Zzvest. Akad. Nauk S.S.S. R . , Neorg. Materialy 1970 6 2143; ( b ) V. V. Safonov and B. G. Lorshunov Zhur. neorg. Khim. 1970,15 2300. 1 2 6 ( a ) A. S . Barabanova Ukrain. khim. Zhur. 1971 37 123; ( b ) H.J. Arpe and H. Kuckertz Angew. Chem. Internat. Edn. 1971 10 73; (c) D. Kobelt and E. F. Paulus, ibid. p. 74. L. E. Alexander and I. R. Beattie J. Chem. SOC. ( A ) 1971 3091. ( a ) R. H. Larkin H. D . Stidham and K. J. Wynne Spectrochim. Acta 1971 27A, 2261 ; ( b ) K. J. Wynne Znorg. Chem. 1971,10 1868; (c) K. J. Wynne and P. S. Pearson, Znorg. Chem. 1971 10 1871. 2 9 J. Derynck and B. Tremillon J. Electroanalyt. Chem. Znterfacial Electrochem. I97 1, 30 443. 130 ( a ) D. J. Stufkens and A. Schenk Rec. Trau. chim. 1971 90 190; ( 6 ) D. J. Stufkens, ibid. 1970,89 1185; (c) C. J. Adams and A. J. Downs Chem. Comm. 1970 1699. 1 2 354 D . W. A . Sharp M . G . H . Wallbridge and J . H . Holloway Measurements of the vibrational spectra of TeXi- (and SbXi-) where X = C1, Br or I have exposed notable departures from the spectroscopic properties of normal octahedral species.'30c The acidity of F,TeOH has been determined spectrophotometrically.' ' The compounds TeF,NMe, TeF,NEt, and TeF,NC,H have been prepared by the reaction of TeF with R2NSiMe3 (R = Me or Et). With excess silylamine the bis-substituted derivatives are formed. Evidence has also been obtained for the formation of TeF,NMeEt TeF,NMeSiMe, and TeF,N(Me)CH,CH,-N(Me)Si(Me,)F.' 32 2 GroupVII A new introductory text on 19F n.m.r. spectroscopy has appeared'33" and toxic properties of inorganic fluorine compounds are the subject of another book. ' 33b Fluorine and non-metal fluoride reactions in electric discharges have been reviewed.'33c Over the past three years a considerable degree of uncertainty has developed over what value should be taken for the bond-dissociation energy of f l ~ 0 r i n e .l ~ ~ " Recent analysis of F photoelectron spectra have led to a value A3F2) = 1.59 f 0.01 eV (153 kJ mol- which is virtually identical with that obtained some time ago by thermodynamic analysis.'34c The value obtained for Ai(HF) (i.e. 5.84 k 0.01 eV)13,' is also in agreement with an earlier spectroscopicvalue.'34d More recently photoelectron spectra of HF and DF obtained with a cylindrical mirror a n a l y ~ e r ' ~ ~ ~ have clearly shown that the dissociation energy of HF cannot be significantly less than 5.86eV and that A;(F,) must therefore be about 1.59 eV. The discrepancies between this recent work'34b*d and earlier photoionization experiments 13," have been largely attributed to the method of choosing thresholds.' 34b of A3C1,) = 57.0 k 0.2 kJ mol-' in excellent agreement with the value obtained from detailed analysis of the visible convergent limit assuming one excited product atom from 3rI&,'35b has been obtained from measurement and analysis of the velocity distribution of the recoiling C1 atoms from the laser-induced photodissociation of C1 .Photoelectron spectra of the halogens A 1 3 1 1 3 2 G. W. Fraser R. D. Peacock andP. M. Watkins J. Chem. SOC. ( A ) 1971 1125. 1 3 3 (a) E. F. Mooney 'An Introduction to Fluorine-19 N.M.R. Spectroscopy' Heyden, London 1970; (b) R. Y. Eagers 'The Toxic Properties of Inorganic Fluorine Com-pounds' Elsevier London 1969; ( c ) I.V. Nikitin and V. Ya Rosolovskii Uspekhi Khim. 1970 39 1161. 1 3 4 ( a ) D. W. A. Sharp M. G. H. Wallbridge and J. H. Holloway Ann. Reports ( A ) , 1970 67 329; (6) J. Berkowitz W. A. Chupka P. M. Guyon J. H. Holloway and R. Spohr J . Chem. Phys. 1971,54 5165; ( c ) J. G. Stamper and R. F. Barrow Trans. Faraday Soc. 1958 54 1592; ( d ) J. W. C. Johns and R. F. Barrow Proc. Roy. SOC., 1959 A251 504; ( e ) J. Berkowitz Chem. Phys. Letters 1971 11 21. 1 3 5 ( a ) R. W. Diesen J. C. Wahr and S. E. Adler J . Chem. Phys. 1971,55 2812; ( b ) R. J. LeRoy and R. B. Bernstein ibid. 1970 52 3869. W. Porcham and A. Engelbrecht Monatsh. 1971 102 333 The Typical Elements 355 (and other mixed halides e.g. ICl and IBr) have been studied.'36 Values of the electron affinities of halogen molecules have been obtained by a variety of techniques.' '"+ Fluorine atoms have been produced in microwave discharges3 9a and the observation by e.s.r. of what are probably C1 atoms on an MgO surface has been r e ~ 0 r t e d . l ~ ~ " Chemical reactions of C1 + I and C1 + IBr have been studied using crossed-molecular-beam apparatus.' 38b Papers on the purification of fluorine by distillation' 39a9b have appeared recently. The energetics of chlorine dissolution in water'40" and the kinetics of dissolution in H,S04 HNO and HC10 have been The redox potentials of the Br,/Br- and I& systems in aqueous acetic acid solution have been measured. l4OC The kinetics of the dissociation-recombination reactions of F and C1 have been critically re~iewed'~'" and spontaneous explosion limits have been obtained141b for mixtures of chlorine and fluorine at 4 0 3 4 7 3 K.There have again been significant additions to our knowledge of halogen-containing anions. The ions Br2- and I,- which are of interest because of their relationship to the excited states of halide ions in crystals in solution have been identified by e.s.r. in y-irradiated barium sulphate doped with bromide or iodide. 142 The formation of 1 1 complexes between S02,62b*c SOCl, or S0,C162b and C1- Br- or I - is of the charge-transfer type and the nature of association between the complexing components has been discussed in relation to the acid-base characters of such components.62b The establishment of conditions under which molten tetra-n-pentylammonium halides decompose only via the route (n-C5Hl 1)4N+X- +(n-C,H 1)3N+n-C,H ,X has permitted the mea-surement of displacement of the halogens by competition experiments and hence the relative nucleophilicity of the halide ions.143a N.m.r. linewidths for 35Cl, 79Br 81Br and 12'1 in aqueous solutions of various substituted phosphonium and sulphonium salts have been shown to be considerably larger than those for aqueous solutions of alkali halides and the broadening is believed to arise from anion-solvent interactions.'43b Raman studies of Br in the presence of halides and pseudo-halides indicates that the bands observed <350cm-' are due to X-Br,-solvent (X = halogen or p~eudo-halogen)'~~' rather than to (Br2)nX-as suggested earlier. 1 3 6 A. W.Potts and W. C. Price Trans. Faraday SOC. 1971 67 1242. 3 7 ( a ) J . J. DeCorpo and J. L. Franklin J . Chem. Phys. 197 1,54 1885 ; ( 6 ) W. A. Chupka, J. Berkowitz and D. Gutman ibid. 1971 55 2724; (c) R. Milstein and R. S. Berry, ibid. p. 4146. 1 3 ' ( a ) A. J. Tench and J. F. J. Kibblewhite J . Chem. Soc. ( A ) 1971 2282; ( b ) J. B. Cross and N. C. Blais J . Chem. Phys. 1971 55 3970. 1 3 9 ( a ) G. Dejachy and J. Gillardeau Bull. SOC. chim. France 1970 2747; (6) E. Jacob, Z . anorg. Chem. 1970,371 267. 140 ( a ) V. A. Kustodina Zhur. priklad. Khim. 1970 43 2096; ( 6 ) I. V. Shimonis and P. V. Dybina Izuest. V . U. Z. Khim. i khim. Tekhnol. 1971,14,208 ; ( c ) L. G . Lavrenova, T. V. Zegzhda and V. M. Shul'man Elektrokhimiya 1971,7 83. 14' ( a ) A. C. Lloyd Internat.J . Chem. Kinetics 1971 3 39; ( b ) S. J. Wiersma and E. A. Fletcher J . Phys. Chem. 1971 75 867. 14' M. C. R . Symons and K. V. S. Rao Chem. Comm. 1971,268. 1 4 3 ( a ) J. E. Gordon and P. Varughese Chem. Comm. 1971 1160; ( b ) H. Wennerstrom, B. Lindman and S. Forsen J . Phys. Chem. 1971 75 2936; (c) M. Delhaye P. Dhamelincourt J. C. Merlin and F. Wallart Compt. rend. 1971 272 A 1003 356 D . W . A . Sharp M . G . H . Wallbridge and J . H . Holloway Reactions between halide and halate have been the subject of several It has been shown that components of the e.s.r. hyperfine tensors and p-character of the unpaired electron in F; decrease with increasing tempera-ture (77-300 K) but the F-F spacing does not change appre~iab1y.l~' The determination of generalized mean-square amplitudes of vibration for various trihalide ions suggests that BrI can be regarded as Br- plus molecular iodine ; for I; BrI; and IBr the charge-transfers from the central atom to the two terminal atoms appear to be of different magnitude^.'^^" The I; ion also seems to be involved in the electrical condition in melts of excess iodine plus tellurium.146b A theoretical investigation of Bri - using the free-electron model for the valence electrons shows that the ion is a typical electron-deficient compound stabilized by a 4 centre-6 electron bond.14' The recent chemistry of halogen and interhalogen cations has been authorita-tively reviewed.'48 The dibromine cation has been the subject of an X-ray structure investigation in the compound (Br,)+ (Sb3F1,)- ; the two bromine atoms are 2.15 8 apart compared with 2.278 in the bromine m ~ l e c u l e .' ~ ~ " The cation 1' is amongst the species produced in the disproportionation of iodine in liquid ammonia. 149b The rate constant of the reaction F + H -+ H + HF has been determined'50a and mechanisms for the reactions of H with F,"Ob and H with F in the presence of 0,' 50c have been studied. Hydrogen-fluoride lasing in flashlamp-initiated N2F4 + CH31151a (the excited HF is formed in the reactions CH + N2F4-CH,NF + NF,; CH,NF -+ HCN + 2HF) and in reactions of N2F4 with CH4,151a7b C2H6 and HCl151b has been reported. The standard enthalpy of solution for gaseous HF at 298 K has been measured'52 by a method devised to minimize the magnitude of gas-imperfection corrections to the ideal gaseous state; the new value is -58.58 kJ mol- '.An important development in the chemistry of anhydrous HF has been the discovery that several hexafluorometallate complexes (K,CuF, K,NiF, and Cs,CoF,) 144 ( a ) P. Crisci and F. Lenzi Canad. J. Chem. 1971 49 2552; ( b ) D. N. Sharma and Y. K. Gupta J. Phys. Chem. 1971,75,2516; ( c ) A. F. M. Barton and Boon-Hian Loo, J. Chem. SOC. ( A ) 1971 3032; ( d ) F. Domka and B. Marciniec Roczniki Chem., 1970,44 1849. 1 4 5 F. J. Owens and 0. R. Gilliam Phys. Status Solidi (B) 1971 43 K3. 146 ( a ) V. U. Nayer and G. Aruldhas Acta Chim. Acad. Sci. Hung. 1971 67 61 ; (b) K. 14' H. Mueller Theor. Chim. Acta 1971 21 110. 14' R. J. Gillespie and M. J. Morton Quart. Rev. 1971 25 553. 149 ( a ) A.J. Edwards and G . R. Jones J. Chem. SOC. ( A ) 1971 2318; ( b ) J. J. Minet, M. Harlem A. Thiebault and G. Fave J. Electroanalyt. Chem. Interfacial Electro-chem. 1971 31 153. I 5 O ( a ) A. F. Dodonov G. K. Lavrovskaya I. I. Morozov and V. L. Tal'rose Doklady Akad. Nauk S.S.S.R. 1971 198 622; (b) G. A. Kapralova E. M. Margolina and A. M. Chaikin ibid. p. 634; ( c ) V. I. Vedeneev Yu. M. Gershenzon A. P. Dement'ev, A. B. Nalbandyan and 0. M. Sarkisov Zzvest. Akad. Nauk S.S.S.R. Ser. khim., 1970 1440. ( a ) T. D. Podrick and G. C. Pimentel J. Chem. Phys. 1971 54 720; (6) L. E. Brus and M. C. Lin J. Phys. Chem. 1971,75 2546. Ichikawa T. Okubo and M. Shimoji Trans. Faraday SOC. 1971,67 1426. 1 5 1 1 5 2 C. E. Vanderzee and W. W. Rodenburg J. Chem. Thermodyn.1971 3 267 The Typical Elements 357 are outstandingly reactive in HF solution ; elemental fluorine is produced and xenon can be f l ~ 0 r i n a t e d . l ~ ~ The method could well provide a means of pre-paring new species of elements in high-oxidation states. Ab initio minimal basis LCAO-SCF-MO calculations suggest that for (HF), polymers n = 3 to n = 6 cyclic structures are most ~ t a b 1 e . I ~ ~ 1.r. studies of HF solutions in organic bases have indicated the formation of bimolecular com-plexes F-H . . . B and multimolecular chain complexes . ' . F-H . . - F-H a - . B. There is no evidence for ionic species resulting from proton transfer from HF to base.' 5 5 a Dilute solutions of organic bases in HF even showed evidence for the protonation of weak bases. The F- anions liberated in these proton reactions are strongly solvated in the form (FH),F- where n > 2.'55b In systems containing HF and various organic bases the hydrogen-bond shift of HF has been shown to be larger than those of any other proton donors.'56 Ab initio LCAO-MO-SCF calculations on HC1 have produced data which, when compared with those for other second-row hydrides show that the accumulation of electrons in the A-H bonds as well as the occupation of the 3d orbitals decreases through the isoelectronic series SiH, PH, H,S and HCl.57 The equilibrium internuclear distance for the HCl molecule (1.27460 0.00005 A) has been obtained from published microwave and i.r. results.'58a A wealth of i.r.15867c and data has been obtained for HCl in the gaseous state,' 58b,d in solution,' 5 8 e ~ J and as crystalline material.' 58c A tempera-ture-dependent study of the i.r.and Raman spectra of liquid and solid fi y and 6 phases of HBr has also been carried out.'59 Raman spectra of HCl guest in P-quinol clathrates have provided evidence for the rotational motion of HC1 guest molecule^.^ Hydrogen halide photolysis is of importance since it provides a convenient source of thermal and &3 eV hot hydrogen atoms; for the first time relative rates of the reaction H + HX -+ H + X (X = I or Br) have been obtained.16' The dihalide anions present an extreme form of hydrogen bonding and these symmetrical systems make their electronic structures of fundamental interest. High resolution 'H and 19F n.m.r. spectra of four dihalide ions have been observed in aprotic solvents and the 'H shielding has been shown to be in every case 14 p.p.m.less than that in the related molecule; the spin-spin coupling in l S 3 T. L. Court and M. F. A. Dove Chem. Comm. 1971 726. I s ' (a) Pham-Van-Huong and M. Couzi J. Chim. phys. 1970 67 1994; (b) M. Couzi and Pham-Van-Huong ibid. p. 2001. H. Touhara H. Shimoda K. Nakanishi and N . Watanabe J. Phys. Chem. 1971, 75 2222. D. Boyd Theor. Chim. Acta 1971 20 273. (a) P. R. Bunker J. Mol. Spectroscopy 1971,39,90; ( b ) M. Buback and E. U. Franck, Ber. Bunsengeseflschaft Phys. Chem. 1971 75 3 3 ; ( c ) J. Blanchard L. C. Brunel and M. Peyron Compt. rend. 1971 272 B 366; ( d ) C. G . Gray Chem. Phys. Letters, 1971 8 527; ( e ) J. P. Perchard W. F. Murphy and H.J. Bernstein ibid. p. 559; (f) M. Perrot Pham-Van-Huong and J. Lascombe J. Chim. phys. 1971,68 614. E. L. Pace Spectrochim. Acta 1971 27A 491. R. D. Penzhorn R. J. Letelier and H. L. Sandoval J. Phys. Chem. 1971 75 835. 1 6 ' J. 0. Lundgren Acta Cryst. 1970 B26 1893. 5 4 J. E. DelBene and J. A. Pople J. Chem. Phys. 1971,55,2296. ' 358 D. W. A . Sharp M . G . H. Wailbridge andJ. H. Hoiioway FHF- is 12.05 +_ 0.3 Hz.16'" The hydrogen dibromide radical BrHBr which is linear and symmetric has been detected by i.r. through matrix isolation,' 62b and so also has BrHBr - . ' 62c The mass spectrum of ClF has been obtained for the first time'63" and mass-spectral sampling behind reflected shock waves has been used to study the decomposition of C1F at 2000-2950 K.'63b The kinetics of iodine bromide formation in 96 % aqueous H2S04 has been IF reacts with halogenated olefins by electrophilic addition to the double bond (e.g.F,C=CF % F,CCF,I).'65 Complexes of ICI and ICl with S 0 3 6 6 c IBr and I with organic amines,'66a and 1,4-dithiane with IBr'66b have been reported. The crystal and molecular structures of C4H,S ,2IBr have been obtained. 1666 Crystal structures for ClFl AsF ''" and ClFT SbF 167b have been obtained and i.r. and Raman spectra for ClF ,SbF, BrF ,SbF6 and C10 ,SbF ' 67c have been reported and assigned. Although in each compound AX ions are postulated the symmetries of the anions are reduced by various degrees of anion-cation interaction. ' 67c Conductivity measurements and freezing points of solutions formed by adding C1 or Br to solutions of iodic acid and iodine in H2S04 are also indicative of the presence of ICl and IBrT s ~ e c i e s .' ' ~ ~ Near-u.v. photolysis of matrix-isolated ClF or ClF-F mixtures at 16 K produce a new i.r. absorption at -575 cm- ' which has been assigned to the asymmetric stretching vibration of the ClF free radical.'68 A new class of compounds containing CIF; have been obtained by the reaction of NOF KF, RbF or CsF with ClF.'69 Interhalogen trichlorides have once again been the subject of much work. Spectroscopic studies initiated last year' 70 have been further amplified by recent work on ClF '' ' a b and BrF ,17 lo+ and there has also been further investigation 1 6 ' ( a ) J. S. Martin and F. Y . Fujiwara Canad. J . Chem. 1971,49,3071; ( b ) V.Bondybey, G . C. Pimentel and P. N . Noble J . Chem. Phys. 1971 55 540; ( c ) D . E. Milligan and M. E. Jacox ibid. p. 2550. 1 6 3 ( a ) S. S. Cristy and G . Mamantov Internat. J . Mass Spectrometry Ion Phys. 1970, 5 309; ( 6 ) J. A. Mcintyre and R. W. Diesen J . Phys. Chem. 1971 75 1765. 1 6 4 R. M. Noyes and P. Schweitzer J . Amer. Chem. SOC. 1971,93 3561. 1 6 s P. Sartori and A. J. Lehnen Chem. Ber. 1971 104 2813. 1 6 6 ( a ) A. K. Trofimchuk and E. Ya. Gorenbein Zhur. obshchei Khim. 1971 41 34; ( b ) J. D. McCullough C. Knobler C. Barker and H. Hope Inorg. Chem. 1971, 10 697. 1 6 ' ( a ) H. Lynton and J. Passmore Canad. J . Chem. 1971 49 2539; ( b ) A. J . Edwards and R. J. C. Sills J . Chem. SOC. (A) 1970,2697; (c) H. A. Carter and F. Aubke Canad.J . Chem. 1970,48 3456; ( d ) J. B. Senior and J . L. Grover ibid. 1971,49 2688. lb8 G. Mamantov E. J. Vasini M. C. Moulton D. G. Vickroy and T. Maekawa J . Chern. Phys. 1971,54 3419. 1 6 9 K. 0. Christe J. P. Guertin and A. E. Pavlath U.S.P. 3 552 936/1971. 1 7 0 D. W. A. Sharp M. G . H. Wallbridge and J. H. Holloway Ann. Reports ( A ) 1970, 67 333. (a) M. Drifford D. Martin and R. Bougon Rev. Chim. minirafe 1970 7 1069; (h) R. A. Frey R . L. Redington and A . L. Khidir Aljibury J . Chem. Phys. 1971, 54 344; ( c ) K. 0. Christie E. C. Curtis and D. Pilipovich Spectrochim. Acta 1971, 27A 93 1 The Typical Elements 3 59 on Raman ir. and electrical conductance studies on liquid BrF,-ClF ' and BrF,-HF',,' mixtures. The kinetics of formation of ClF from fluorine and from chlorine monofluoride have been studied,'73a and the standard heat of formation of ClF,(g) at 298.15 K has been determined as - 164.65 kJ mol- ' in a flame ca10rimeter.l~~~ The chlorine 3d orbitals in ClF and other halides have been shown to be contracted in the presence of electronegative ligand~.~, ICl has been shown to produce the ICll ion in disulphuric Microwave studies have yielded rotational constants for 79BrF, ''BrF,, and IF 174a*b and these together with electron-diffraction data,174c have been used to evaluate the structures.1.r. spectra of ClF in a matrix have confirmed the unusual triple coincidence of two deformational and one stretching mode at ca. 480 cm- ' suggested earlier and evidence for the association of ClF in the pure solid and in an Ar matrix at low dilutions has been obtained.' 74d Molecular potential-energy constants for ClF and BrF have been calculated.' 74e A number of thermodynamic properties of IF, including the heat capacity between 5 and 350 K the enthalpy of fusion and vaporization and the standard entropy of the vapour have been measured.' X-Ray diffraction studies indicate that MBrF (M = K Rb or Cs) crystallize in the rhombohedra1 system and i.r. and Raman data show that the F-octahedron around the bromine is distorted about the ternary axis to give D, site symmetry for bromine. 176 Electron diffraction studies on IF indicate that the vapour-phase molecules are pentagonal bipyramids with axial bonds shorter than equatorial ; the molecules are distorted from D, symmetry.'77 Polarization studies on the Raman spectrum of C1,O have confirmed the i.r.assignment,17*" and argon-matrix i.r. spectra of the ClO radical have been ~btained.'~'' Dissociation energy ionization potential electron affinity and dipole and quadrupole moments have been obtained for C10 from ab initio MO calculation^.'^^ Investigations of the flash photolysis of C10 and of its photo-sensitized decomposition by C1 or Br have yielded rate constants for a number of reactions."Oa The production and reactions of Br0'''' and C10'80b~' by '" ( a ) H. H. Hyman T. Surles L. A. Quarterman and A. 1 . Popov Inorg. Chem. 1971, 10 913; (b) ibid. p. 611. ( a ) E. A. San Roman and H. J. Schumacher Z . phys. Chem. (Frankjkrt) 1970 71, 153; (b) R. C. King and G. T. Armstrong J .Res. Nut. Bur. Stand. Sect. A 1970, 74 769. 1 7 4 (a) M. J. Whittle R. H. Bradley and P. N. Brier Trans. Furaday SOC. 1971,67,2505; (b) R. H. Bradley P. N. Brier and M. J. Whittle Chem. Phys. Letters 1971 1 1 192; (c) A. G. Robiette R. H. Bradley and P. N. Brier Cliem. Comm. 1971 1567 (d) K . 0. Christe Spectrochim. Acta 1971 27A 631; ( e ) K. Ramaswamy and P. Muthusu-bramanian J . MoI. Structure 1971 7 45. 1 7 5 D . W. Osborne F. Schreiner and H. Selig J . Chem. Phys. 1971,54 3790. R. Bougon P. Charpin and J. Soriano Compt. rend. 1971 272 C 565. 1 7 ' W. J. Adams H. B. Thompson and L. S. Bartell J . Chem. Phys. 1970,53 4040. 1 7 ' ( a ) D. J. Gardiner J . Mol. Spectroscopy 1971 38 476; ( 6 ) L. Andrews and J. I. '19 P. A. G. O'Hare and A. C. Wahl J . Chem.Phys. 1971,54 3770. ''' (a) N. Basco and S. K. Dogra Proc. Roy. SOC. 1971 A323 401 ; (b) ibid. p. 417; Raymond J . Chem. Phys. 1971,55 3087. ( c ) ibid. p. 29; (6) J. Brown and G . Burns Canad. J . Chem. 1970 48 3487 360 D . W. A . Sharp M . G . H . Wallbridge and J . H. Holloway the halogen-sensitized decomposition"0b or the isothermal flash photolysis''O' of BrO and C10 have also been studied. Kinetic spectroscopy has been used to study the decomposition of BrO.lSod The e.s.r. spectrum of C10 has been detected in y-irradiated NaClO at 19 K."' The zero-point (0 K) average structure of C10 from electron diffraction results has been shown to agree well with that determined from microwave data. l S 2 Following the discovery of chlorine perchlorate last year the related BrOClO, has now been prepared's3" and the vibrational spectra of gaseous and matrix-isolated ClOClO and BrOClO, and ClOClO in the solid and liquid states, have been in~estigated."~~ The i.r.and Raman spectra of the chlorine trioxide dimer at 87K have been shown to be compatible with the ionic formulation C10,fC10,.''3c The decomposition of bromite BrO, has been the subject of two recent investigations.' '4a*b The flash photolysis of aqueous solutions of chlorate ion has been shown to give rise to OH C10- and 0 and C10, ~pecies.''~ Chlorate bromate and iodate XO are oxidized to the respective perhalate XO, by XeF in aqueous solution.''6u The rate expression -d[BrO,]/dt = k'[BrO;][VO2+] has been found to be operative for the reaction BrO; + 5 V 0 2 + + 2H,O -+ 0.5 Br + 5 VO; + 4 H+ in perchloric acid solution."6b The X-ray crystal structure of NH4103 has been investigated.It consists of discrete 10; pyramidal ions arranged to give a much distorted octahedral environment about the iodine. The 10 ions and the NH ions form chains pardel to the polar axis. '' 7 a The sodium periodate structure has been refined,' ' 7b and the vibrational spectra of 10 and H410; in a number of salts have been ~tudied"~' with special emphasis on the influence of the cation and of the crystal symmetry on the spectrum of the 10,. Further i.r. studies on I,O, HI,O,, HIO, and NaIO have been reported"8a and the polymeric nature of 1205 suggested on the basis of the i.r. work' 88a seems to be borne out by X-ray crystallo-graphic examination.' ''b OClF has been prepared by the U.V.irradiation of a mixture of ClF and and FClO has been synthesized by heating mixtures of oxygen and ClF.19' The n.m.r. spin-lattice relaxation times of 35Cl and 19F have been l S 1 l E 2 A. H. Clark J. Mol. Structure 1971 7 485. l g 3 (a) C. J. Schack K. 0. Christe and D. Pilipovich Znorg. Chem. 1971 10 1078; ( 6 ) K. 0. Christe C. J. Schack and E. C. Curtis ibid. p. 1589; ( c ) A. Pavia J. L. Pascal, and A. Potier Compt. rend. 1971 272 C 1495. l g 4 (a) A. Massaqli A. Indelli and F. Pergola Znorg. Chim. Acta 1970 4 593; ( b ) C. L. Lee and M. W. Lister Canad. J. Chem. 1971,49 2822. IE5 F. Barat L. Gilles B. Hickel and B. Lesigne J. Phys. Chem. 1971 75 2177. (a) E. H. Appleman Znorg. Chem. 1971,10 1881 ; ( b ) R.C . Thompson ibid. p. 1892. I g 7 (a) E. T. Keve S. C. Abrahams and J. L. Bernstein J. Chem. Phys. 1971 54 2556; ( 6 ) A. Kalman and D. W. J. Cruickshank Acta Cryst. 1970 B26 1782; (c) H. Siebert and G. Wieghardt Spectrochim. Acta 1971 27A 1677. (a) P. M. A. Sherwood and J. J. Turner Spectrochim. Acta 1970 26A 1975; (6) A. Selke and A. Kjekshus Acta Chem. Scand. 1970 24 1912. I g 9 R. Bougon J. Isabey and P. Plurien Compt. rend. 1970 271 C 1366. J. P. Faust A. W. Jache and A. J. Klanica U.S.P. 3 545 924/1970. M. C. R. Symons J. Chem. SOC. ( A ) 1971 698 The Typical Elements 361 measured over the entire liquid range of C103F (130-368 K).191 Raman spectra of IOF have confirmed the expected C, symmetry.'92 An e.s.r. study of the IO,F- radical has shown that the unpaired electron is predominantly delocalized over the I and 0 atoms and interacts only weakly with the F atom.'93 Vibrational spectra of FOS02F and C10S02F have been interpreted in terms of C symmetry for the molecules.The polarized Raman spectrum for peroxy-disulphuryl difluoride indicates a staggered non-planar configuration with C2 symmetry.'94 The Raman spectra of BrOS0,F and Cs[Br(OSO,F),] have also been recorded. ' Two reports of the production and identification of the perastatate ion have appeared recently; astatine was oxidized to AtO with XeF2,196avb K 2 S 2 0 87 KOCI or by anodic oxidation. 196b 3 GroupVIII A book on ,He has appea~ed'~' and recent developments in noble-gas chemistry have been reviewed.'98 Although there have not yet been reports of strongly bonded compounds involving He Ne or Ar it has been shown empirically that ArF+ is remarkably stable [D,(ArF+) 3 1.655eVl although NeF' and HeF' are not.'99 Non-empirical quantum-mechanical calculations on KrF and KrF+ lead to the con-clusion that KrF is unlikely to exist in the gas phase and the predicted value for the dissociation energy is Do = 1.90 eV200 (cJ measured value Do = 1.58 eV"').The valence-level photoelectron spectrum of KrF indicates an MO ordering identical with that of XeF and a remarkable similarity of orbital energies.201 The kinetics of the thermal decomposition of KrF have been studied.202 Some aspects of krypton-oxygen bonding have been studied by Mossbauer spectro-It has been shown that the magnetic parameters derived from the e.s.r.spectrum of XeF in y-irradiated XeF at 77 K are comparable with those obtained some years ago in XeF .204 An ab initio self-consistent-field computation has been performed on the series XeF, XeF, and XeF and the charge distributions, photoelectron and optical spectra and one-electron properties are discussed A. A. Maryott T. C. Farrar and M. S. Malmberg J. Chem. Phys. 1971,54 64. 1 9 ' J. H. Holloway H. Selig and H. H. Claassen J. Chem. Phys. 1971 54 4305. 1 9 3 S. Subramanian and M. T. Rogers U.S. Atomic Energy Commiss. 1970 COO-1385-34 scopy.203 (Nuclear Sci. Abs. 1971 25 18 420). A. M. Qureshi L. E. Levchuk and F. Aubke Canad. J. Chem. 1971,49 2544. 19' F. Aubke and A. M. Qureshi Inorg. Chem. 1971,10 11 16. 1 9 6 ( a ) V. A. Khalkin Yu. V. Norseev V.D. Nefedov M. A. Toropova and V. I. Kuzin, Doklady Akad. Nauk S.S.S.R. 1970 195,623; (b) G. A. Nagy P. Groz V. A. Hakin, Do Kim Tuong and Yu. V. Norseev Kozp. Fiz. Kut. Intez. Kozlem. 1970 18 173. N. K. Jha R.I.C. Reviews 1971,4 147. B. Liu and H. F. Schaefer J. Chem. Phys. 1971,55 2369. C. R. Brundle and G. R. Jones Chem. Comm. 1971 1 198. 19' Z. M. Galasiewicz 'Helium-4' Pergamon Oxford 1971. l 99 J. Berkowitz and W. A. Chupka Chem. Phys. Letters 1970 7 447. ' 0 1 'O' V. N. Prusakov and V. B. Sokolov Kinetika i Kataliz 1971 12 33. '03 Y. Hazony and R. H. Herber J. Inorg. Nuclear Chem. 1971 33 961. '04 M. C. R. Symons and R. S. Eachus J. Chem. SOC. ( A ) 1971 304 362 D . W. A . Sharp M . G . H . Wallbridge and J . H . Holloway and compared with experimental data.,"* Photoelectron spectra for XeF 2 0 5 b 9 c XeF and XeF6205C and photoionization mass-spectrometric investigations on the xenon fluoridesZoSd have been carried out.The photoionization studies have provided new values for the heats of formation of the binary fluorides, namely AHFo(XeF,) = - 117 f 2 kJ mol- ' AHPO(XeF,) = - 241 & 8 kJ mol- ', and dH,O,(XeF,) = -376:;; kJ mol-'.205d The critical temperature of XeF, has been measured (608 K).,06 Raman spectra of XeF, XeF, and XeOF, vapours have been obtained and normal co-ordinates and force constants have been determined.," The influence of some metal fluorides on the reaction of xenon with fluorine have been studied and the catalytic influence of NiF has been found to be the greatest.208 New complexes formed from XeF include XeMnF6 ,20ya XeF,,-VF ,,09' FXeOTeF ,,09' and Xe(O,CCF,) ,,OYc and phase diagram studies are said to indicate the formation of the compounds XeF ,2BrF and XeF,,9BrF,.209d FXeOTeF reacts with AsF to form the 1 1 adduct [XeOTeF,]' [AsF,]-which means that the fluoride-ion donor strength of FXeOTeF lies between that of XeF and XeF .209e Other phase diagram analyses of the XeF,-SbF,,209J XeF,-NbF and XeF,-TaF,209g systems confirm earlier studies.Further details of the reactions of XeF with benzene and substituted benzenes have appeared,2'o".b and e.s.r. studies on the systems at low temperatures in the presence of HF have shown that radical cations of polyphenyls are XeF oxidizes I - to I IO, and eventually to 10 in acidic solution. This has been exploited analytically and KI was determined with an error of - 0.64 %.' Raman data indicate that the complex XeF ,2SbF should be formulated [XeF,]' [Sb2F11]- and this is confirmed by I9F n.m.r. data.,', More information has been published on the structure of the tetrameric phases in XeF . 1 3 " 2NOF,XeF has been shown to consist of well-separated NO+ ' 0 5 ( a ) H. Basch J. W. Moskowitz C. Hollister and D. Hankin J . Chem. Phys. 1971, 55 1922; (6) B. Brehm M. Menzinger and C. Zorn Canad. J. Chem. 1970,48 3193; ( c ) C. R. Brundle G. R. Jones and H. Basch J . Chem. Phys. 1971 55 1098; ( d ) J. Berkowitz W. A. Chupka P. M. Guyon J. H. Holloway and R. Spohr J. Phys. Chem. 1971,75 1461. P. Tsao C. C. Cobb and H. H. Claassen J. Chem. Phys. 1971,54 5247.B. Zemva and J. Slivnik Inst. Jozef Stefan IJS Rep. 1970 R-589; see also B. Zemva, '09 ( a ) B. Zemva J. Zupan and J. Slivnik J. Inorg. Nuccear Chem. 1971 33 3953; see also Inst. Jozef Stefan IJS Rep. 1970 R-585; ( 6 ) B. Zemva and J. Slivnik J . Inorg. Nuclear Chem. 1971,33 3952; ( c ) F. 0. Sladky Monarsh. 1970 101 1571 ; ( d ) V. N. Prusakov V. B. Sokolov and B. B. Chaivanov Zhur. Jiz. Khim. 1971 45 1102; ( e ) F. 0. Sladky Monatsh. 1970 101 1578; (f) V. A. Legasov V. N. Prusakov and B. B. Chaivanov Zhur. Jiz. Khim. 1970 44 2629; ( g ) V. A. Legasov and B. B. Chaivanov ibid. 1971 45 593. ' I o ( a ) M. J . Shaw J. A. Weil H. H. Hyman and R. Filler J. Amer. Chem. SOC. 1970, 92 5096; (6) M. J. Shaw H. H. Hyman and R. Filler ibid. p. 6498. ' A. Schneer-Erdey and K.Kozmutza Magyar Kem. Folyoirat 1971,77 97. R. J. Gillespie B. Landa and G. J. Schrobilgen Chem. Comm. 1971 1543. 2 1 3 ( a ) R. D. Burbank and G. R. Jones Science 1971 171 485; ( 6 ) S. W. Peterson J. H. Holloway B. A. Coyle and J. M. Williams ibid. 1971 173 1238. ' 0 6 T. Ogrin J. Slivnik and B. kemva Croat. Chem. Acta 1971,43 87. Inst. Jozef Stefan IJS Porocilo 1971 P-265 The Typical Elements 363 and [XeF8l2- ions; the anion configuration is that of a slightly distorted Archi-medean antiprism.213b Molecular parameters for XeOF obtained from electron diffraction data are in general agreement with vibrational and rotational spectroscopic data.2 l 4 However each set of parameters suffers from fairly large uncertainties which are not related to the accuracy of the respective physical measurements.Excellent vibrational spectroscopic data have been obtained for Xe0,F221 5u (D3h symmetry is indicated) and for several alkali-metal halogenoxenates MXeO F2 ' 5 b (where M = K Rb or Cs). Raman spectroscopic investigation of aqueous Xe'"' has shown that HXeOi- is the predominant species in most alkaline solutions and that XeO2- is never a principal species. ' 5 c The perxenate Na,XeO ,6H20, has been studied thermogravimetrically at <473 K it loses all its water and then loses Xe at -650 K to give Na,O(Na,O,) and at > 773 K to give Na,0.216 The behaviour of XeO in aqueous and non-aqueous solvents has been authoritatively reviewed. '' A kinetic study of the oxidation of some alcohols by XeO has revealed the optimum conditions for the analysis of these sub-stances.'' The y-irradiation of aerated and deaerated aqueous solutions of XeO gave Xe and molecular oxygen.219 When gaseous 25 1 Xe-C1 mixtures were passed through a microwave discharge and condensed on the cold tip of a Raman matrix cell a single band appeared at 253 cm-' in the laser-excited Raman spectrum. This has been attributed to the Xe-Cl stretching mode of linear XeC1,.220 L. S. Bartell E. J . Jacob and H. B. Thompson J . Mol. Structure 1971 8 383. 2 1 5 (a) H. H. Claassen and J. L. Huston J . Chem. Phys. 1971,595 1505; (6) P. LaBonville, J. R. Ferraro and J. M. Spittler ibid. p. 631; ( c ) E. H. Appelman G . D. Downey, and H. H. Claassen Inorg. Chem. 1971 10 1817. ' 1 6 V. Ya. Mishin I. S. Kirin V. K. Isupov and Yu.K. Gusev Zhur. neorg. Khim., 1971 16 51. 2 ' 7 B. Jaselskis Rec. Chern. Progr. 1970 31 103. 'I8 R. H. Kreuger S. Vas and B. Jaselskis Talanta 1971 18 116. 2 1 9 C. Heitz and F. Simon Radiochem. Radioanalyt. Letters 1970 5 341. ''O D. Boa1 and G. A. Ozin Spectroscopy Letters 1971 4 4 3

ISSN:0069-3022    

DOI:10.1039/GR9716800253

出版商:RSC    

年代:1971

数据来源: RSC

摘要:

14 The Transition Elements By R. J. CROSS and J. M. WINFIELD Department of Chemistry The University of Glasgo w 1 Introduction THE chemistry of the transition elements excluding their organometallic com-pounds and related topics which are discussed in Chapter 15 forms the subject for this Report. The division of the subject and the selection of work discussed here are rather arbitrary although the latter problem is less serious this year with the advent of Specialist Periodical Reports (Inorganic Chemistry of the Transition Elements ; Senior Reporter B. F. G. Johnson) covering the field. The elements are dealt with on a Group basis followed by a section dealing with ligands. Magnetic and spectroscopic properties are reported as appropriate, in the Group or Ligand sections.Nomenclature.-Metals are denoted by M cations by A anions by X organic radicals by R and ligands by L using Latin numerical prefixes to indicate den-ticity e.g. biL for a bidentate neutral ligand. Positive oxidation states are indi-cated by capital Roman numerals. When possible the first co-ordination sphere is indicated by square brackets and the structures of polynuclear compounds are denoted following current usage e.g. anhydrous Mo" chloride is [(Mo,CI,)-Commonly used ligands are abbreviated as follows dimethyl sulphoxide (DMSO) ethylenediamine (en) pyridine (py) 2,2'-bipyridyl (bipy) terpyridyl (terpy) 1,lO-phenanthroline (phen) 8-quinolinolato (oxine) 1,2-bis(diphenyl-phosphino)ethane (diphos) o-phenylenebis(dimethy1arsine) (diars) acetylaceto-nato (acac) benzoylacetonato (benzac) NN'-bis(salicyla1dehydo)ethylenedi-imi-nato (salen) acetate (OAc) oxalate (ox) and ethylenediaminetetra-acetato (edta).From the many papers dealing with transition elements we select two topics, super-heavy elements and nitrogen fixation under mild conditions where developments this year have been of general interest. Super-heavy Elements.-The controversy over the identification of element 104 still simmers in the literature. The Dubna group have published details of the fission events that they claim originated from 2 5 9 K ~ (kurchatovium) t+ = ca. 4-5 s," but the Berkeley group believe that they are due to 256Md or 256Fm.'b Cl2C~4,2luJ * ( a ) I. Zvara V. Z. Belov L. P. Chelnokov V. P. Domanov M. Hussonois Yu. S. Korotkin V.A. Schegolev and M. R. Shalayevsky Inorg. Nuclear Chem. Letters, 1971 7 1109; ( 6 ) A. Ghiorso M. Nurmia K. Eskola and P. Eskola ibid. p. 11 17; ( c ) A. Ghiorso M. Nurmia J. Harris K. Eskola and P. Eskola Nature 1971 229, 603 366 R . J. Cross and J. M . Winfield The latter workers have restated their case for naming element 104 as ruther-fordium." The possible formation of element 112 eka-mercury in the bom-bardment of a W target with 24 GeV protons has been suggested.2" High-angle recoils and heavy-particle interactions produce heavy atoms with sufficient recoil energy to fuse with neighbours and asymmetric fission could produce 'stable' super-heavy elements. The species is carried by Hg and the sequence is characterized by 6-73 MeV a-emission and spontaneous fission.Although this interpretation is not supported by 28.5 GeV proton bombardment of W Au, or U targets,2b and ca. 70% of the fission activity can be assigned to 2'2Cf the residual fission spectra differ considerably from those of any known actinide.2c Bombardment of a Th target with 500 MeV Kr2,+ ions induces complete fusion. Formation of elements of atomic number 2 102 is inferred as energies in the range 13-15 MeV are observed in the a-particle spectrum of the product^.^ Speculation continues about the properties of elements of even higher atomic number. For example relativistic Hartree-Fock calculations suggest that the most common oxidation state for element 164 will be +2 and that element 184 will have oxidation states from + 4 to + 12 (with 8 and 0 6g electrons respec-tively) !, A related topic of general interest is the mass spectrometric detection of 244Pu (1 part in in Precambrian bastnasite.' While a cosmic-ray source cannot be ruled out completely it seems likely that 244Pu along with 238U 235U and 232Th, survive from the formation of the solar system.The relative isotopic abundances suggest that nucleosynthesis began in the galaxy ca. (12 k 2) x lo9 years ago and continued until the solar system was formed ca. 4.7 x lo9 years ago. Nitrogen Fixation Studies.-Although this topic has had a varied history two groups this year have reported the reduction of N under mild conditions. N2H, is the principal product with NH3 being formed at higher temperatures from the reduction of N in aqueous solution (pH > 7) at ambient temperatures by Ti3+ or Cr2+ in the presence of MeV' or MoV.V2+ is more active and reduction occurs even in the absence of Mo. The presence of Mg2+ strongly activates reduction, particularly with Ti3+ and V2+ and in all cases reduction is inhibited by C0.6 Reduction of N in Mo-thiol-Fe'I-BH - systems has been previously claimed (see last year's Report and ref. 7) but often high pressures are necessary and (a) A. Marinov C . J. Batty A. L. Kilvington G. W. A. Newton V. J. Robinson and J. D. Hemingway Nature 1971,229,464; (b) S . Katcoff and M. L. Perlman ibid. 1971, 231 522; (c) A. Marinov C. J. Batty A. I. Kilvington J. L. Weil A. M. Friedman, G. W. A. Newton V. J. Robinson J. D. Hemingway and D. S. Mather ibid. 1971, 234 212. R. Birnbot C.Deprun D. Gardes H. Gauvin Y. Le Beyec M. Lefort J. Peter and B. Tamain Nature 1971 234 215. R. A. Penneman J. B. Mann and C . K. Jsrgensen Chem. Phys. Letters 1971 8, 321. D. C. Hoffman F. 0. Lawrence J. L. Mewherter and F. M. Rourke Nature 1971, 234 132. A. Shilov N. Denisov 0. Efimov N. Shuvalov N. Shuvalova and A. Shilova Nature, 1971,231,460. G. N. Schrauzer G. Schlesinger and P. A. Doemeny J . Amer. Chem. SOC. 1971 93, 1803 The Transition Elements 367 yields are small. A modification of this approach using Moo,'- Fe" NaBH,, and 2-aminoethanethiol leads to high yields of I5NH3 from "N at ambient pressures.' In this work also the reduction of I5N2 to 15N2H4 using V2+ or Mo3 + was confirmed. Reviews.-Solid-state and solution chemistry are featured in reviews dealing with synthetic work in the solid ~ t a t e ' ~ with the thermodynamics of metal-complex and ion-pair formation," and with transition-metal oxo-complexes.9c Spectroscopic and ligand-field properties of transition-metal compounds con-tinue to receive attention and recent reviews include coverage of the following topics electronic spectra of open-shell molecules at high temperatures para-magnetic anisotropy y-resonance spectroscopy n.m.r.spectroscopy of para-magnetic complexes the calculation and accuracy of interelectronic repulsion parameters in cubic high-spin d" systems and MO calculations on transition-metal complexes." A bibliography of current structure determinations of in-organic compounds is now published in Co-ordination Chemistry Reviews.2 The Rare Earths Scandium.-Little work on this element has been reported this year although the interest of Soviet chemists is apparent. A series of complexes of stoicheiometry Sc(NCS),(py),(EtOH) (n = 1-4 m = 0 or 1) has been isolated of which Sc(NCS),(py) appears to be the most stable. In all cases dissociation occurs in water and the presence of S~(py),~+ cations is suggested." Complexes with bidentate ligands reported this year include [(phen)(ox)Sc(ox)Sc(ox) (phen)] in which six-co-ordination of Sc is suggested,' ' and A'[Sc(biX),] (biX = fluorinated derivatives of acac).' The latter compounds sublime without decomposition at 4 1 3 4 7 3 K and are reminiscent of similar compounds formed by lanthanides and actinides. Yttrium and the Lanthanides.-As usual many papers on these elements have appeared and one of the main preoccupations has been the stereochemistry of Ln"' complexes.Stereochemical changes along the series are common. For example an i.r. spectroscopic study of matrix-isolated LnF has indicated that these molecules are planar for Ln = La Ce Sm or Eu whereas PrF is pyra-midal.I4 Often the changes are subtle as in LnFeO where the co-ordination R. E. E. Hill and R. L. Richards Nature 1971 233 114. ( a ) H. Schafer Angew. Chem. Internat. Edn. 1971 10 43; ( 6 ) G. H. Nancollas Co-ordination Chem. Rev. 1970 5 379; (c) w . P. Griffith ibid. p. 459. l o D. M. Gruen Progr. Znorg. Chem. 1971 14 119; W. Dew. Horrocks jun. Co-ordination Chem. Rev. 1971 6 147; R. L. Mossbauer Angew. Chem. Internat. Edn., 1971 10 462; K.E. Schwarzhans ibid. 1970,9 946; E. Konig Structure and Bonding, 1971 9 175; D. A. Davies and G . A. Webb Co-ordination Chem. Rev. 1971 6 95. T. M. Sas L. N. Komissarova and N. I. Anatskaya Russ. J . Znorg. Chem. 1971, 16 45. B. N. Ivanov-Emin R. K. Gridasova B. E. Zaitsev G. Val'karsel and A. I. Ezhov, Russ. J . Znorg. Chem. 1970 15 347. M. Z. Gurevich B. D. Stepin L. N. Komissarova N. E. Lebedeva and T. M. Sas, Russ. J . Znorg. Chem. 1971 16 48. I * l 3 l 4 R. D. Wesley and C . W. DeKock J . Chem. Phys. 1971,55 3866 368 R . J . Cross and J. M . Winjield number of Ln approximates to eight but is a good approximation only between Tb and Nd. Between Dy and Lu the seventh and eighth Ln-0 distances increase as the size of Ln3+ decreases while at La the difference between the eighth and ninth La -0 distances is not large enough to assume that La is eight-co-ordinate.In other X-ray work it has been shown that Pr and Ce are nine-co-ordinate in [Pr(terpy)Cl(OH,),]CI ,2H20 and CeCrSe, the co-ordination polyhedra being a monocapped square antiprism and a tricapped trigonal prism respectively. l 6 Lanthanide P-diketonate complexes continue to be widely studied partly because of their utility as n.m.r. shift reagents. X-Ray work on Pr(Me,C,CO.CH-COCMe,) and Pr(C3F7COCHCOCMe3) ,H,O has shown that both are dimeric being [(biX),Pr(terX),Pr(biX),] with seven-co-ordinate Pr and [(biX),Pr(terX),(H,O)Pr(biX),],H,O with eight-co-ordinate Pr. l7 In the latter compound the Pr atoms have different co-ordination geometries dodecahedra1 and dicapped trigonal prismatic and the two Pr(biX) octahedra from which the polyhedra are derived have cis and trans configurations re~pectively."~ The spectroscopic and magnetic properties of Pr(Me,C-COCHCO-CMe,) and the isomorphous Eu analogue in non-polar organic solvents have been interpreted in terms of a monomer-dimer equilibrium.In basic solvents (L) Ln(biX),L are formed whose spectra resemble those of [Ln(biX),], and are very different from [Ln(biX),].'8" Evaluation of the formation constants for Eu(biX),L (L = n-propylamine or neopentyl alcohol) from a 'H n.m.r. study indicates that the former is more strongly bound.lgb The luminescence spectra of A[Eu(Ph.-COCHCO-Ph),] in which A = Group I cation or Bu",N+ provide evidence for D or D site symmetry at Eu depending on the cation.In some cases the conversion D + D is observed on heating." The weak metal-ligand bonding characteristic of Ln"' complexes [illustrated this year by the series A,A'Ln(N02)6 for which Ln3 +,ONO- bonding is indicated from their electronic and vibrational spectra2'] means that considerable attention is paid to equilibria in solution. From a calorimetric and pH study2'" of the formation of mixed 1 1 1 Ln3+ edta X complexes (X = 8-hydroxyquinoline-5-sulphonate iminodiacetate or nitrilotriacetate) it has been concluded that all Ln"' aquo-ions have the same co-ordination number in dilute solution in con-trast to the generally accepted view. In the series [Ln(edta)(H,O),]- there is a co-ordination number change between Sm and Tb and in this region an equi-librium of the type [Ln(edta)(H,O),]- * [Ln(edta)(H,O),- '1- + H 2 0 can be M.Marezio J. P. Remeika and P. D. Dernier Acta Cryst. 1970 B26 2008. l 6 L. J . Radonovich and M. D. Glick Znorg. Chem. 1971 10 1463; Nguyen-Huy-Dung, J. Etienne and P. Laruelle Bull. SOC. chim. France 1971 2433. ( a ) C. S. Erasmus and J. C. A. Boeyens Acta Cryst. 1970 B26 1843; ( 6 ) J. P. R. de Villiers and J. C. A. Boeyens ibid. 1971 B27 692. ( a ) M. K. Archer D. S. Fell and R. W. Jotham Inorg. Nuclear Chem. Letters 1971, 7 1135; (b) I. Armitage G. Dunsmore L. D. Hall and A. G. Marshall Chem. Comm., 1971 1281. l 9 E. Butter and W. Seifert Z . anorg. Chem. 1971 384 67. 2 o J. C. Barnes and R. D. Peacock J. Chem. SOC. ( A ) 1971 558. 2 1 (a) G. Geier and U.Karlen Helu. Chim. Acta 1971 54 135; ( b ) G. Geier and C. K. Jsrgensen Chrm. Phys. Letters 1971 9 263 The Transition Elements 369 detected. For Ln = Eu there is a difference of 14 cm- in the 'Do + 7F0 transi-tion energies between the two complexes and a temperature variation study indicates an enthalpy change of 18 kJ mol- associated with the loss of H20 in good agreement with the calorimetric The '"Eu Mossbauer spectra of frozen solutions of Eu"' in aqueous HCl are pH dependent and suggest the formation of Eu"' aquo-chloro-complexes in solution.22 Illustrating the behaviour of Ln"' complexes in non-aqueous solvents are two papers which examine equilibria in CH,C12 and MeCN., A spectroscopic study suggests that in CH,Cl, the complex [YbL,(NO,),] (L = tri-2-propyl-phosphate) dissociates to give [YbL,(NO,),] + L and that LnL,(N03),(H20) (Ln = T b L u ) give LnL,(NO,) + LnL,(NO,) in solution while Ln(NO,),-(H20)6 are pre~ipitated.,~" Although [Ln(terL),] (NO,) and [Ln(terL),-(N03),]N03 (terL = diethylenetriamine) are isolated from MeCN solution, conductivity and enthalpy data show that [Ln(terL),(NO,),]' are the thermo-dynamically favoured species in solution.23b Further work on the interpretation of the single-crystal magnetic properties of [LnL,]I (L = antipyrine) complexes (see last year's Report) has appeared.24 The calculations for Tb and Nd use complete and incomplete Russell-Saunders terms respectively as bases taking account of a partial breakdown in the scheme.For Er the effects of intermediate coupling are considered but they have only a slight effect on the magnetic moments.Far less work on other oxidation states has appeared. The crystal structures of two Ce" compounds have been reported. Ce" is ten-co-ordinate in [Ce(NO,),-(OPPh,),] and the arrangement of ligands may be described in terms of a dis-torted octahedron comprising Ph,PO and NO ligands in a trans configuration. The (P)OCeO(P) system is non-linear and this and the compound's i.r. spectrum are advanced as evidence for 7c-donation from Ph,PO to Ce.25 In a further report on the NH,F-CeF,-H20 system the crystal structure of (NH4),CeF7 ,-H 2 0 has been shown to contain dodecahedrally co-ordinated Ce in [F6CeF2CeF,l6- anions. The structure features OH. * .F and NH. * -F hydrogen-bonding. , The i.r.spectra of matrix-isolated EuX (X = F or C1) indicate that both mole-cules are non-linear with XEuX angles of 100 & 15" and 135 & 8" re~pectively.,~ An anomalous charge state l 5 'Eu2 + is produced from the electron-capture decay of 151Gd3+ in Er,(ox),,10H20 as host lattice. This is not observed with Er,O or ErF, 2H,O as hosts and is considered to reflect the reducing properties of ox when subjected to radiolysis.28 2 2 N. N. Greenwood G. E. Turner and A. Vertes Inorg. Nuclear Chem. Letters 1971 7 , 389. 2 3 (a) J . R. McRae and D. G. Karraker J . Inorg. Nuclear Chem. 1971 33 479; (b) J. H. Forsberg and C. A. Wathen Znorg. Chem. 1971 10 1379. 2 4 M. Gerloch and D. J. Mackay J . Chem. SOC. ( A ) 1971,2605 2612 3372. 2 5 Mazhar-U1-Haque C. N. Caughlan F.A. Hart and R. VanNice Innorg. Chem. 1971, 10 115. 2 6 R. R. Ryan and R. A. Penneman Acta Cryst. 1971 B27 1939. " J . W. Hastie R. H. Hauge and J. L. Margrave High Temp. Sci. 1971,3 56. 2 8 P. Glentworth A. L. Nichols N. R. Large and R. J. Bullock Chem. Comm. 1971,206 370 R. J . Cross and J . M . Winjield 3 The Actinides The production of sufficient 249Bk by neutron capture at 242Pu or 244Cm to allow 'possible loss' experiments to be attempted has led to the isolation of 'bulk' samples of berkelium metal. These were prepared by the reduction of BkF by lithium in a tantalum crucible at 1300 K. Two crystalline modifications were revealed by X-ray methods face-centred-cubic and double-hexagonal-clo~e-packed.~~ This is the first new actinide metal structure reported since that of curium in 195 1.Berkelium begins the second half of the 5f series. The reaction of metallic uranium with HCI or HBr under anaerobic conditions produces a precipitate believed to be an uranium h~dride.~' This compound inflames in air when dry and decomposes to uranium metal at 730 K. Evidence has been obtained for the existence of dipositive californium from studies on the distribution of actinides between molten LiCl and Li-Bi solution^.^ Cf" was present in the salt phase when the amount of lithium in the bismuth was greater than 0.02 atom %. Best values for the standard (IIIHIV) oxidation poten-tials of both the actinides and lanthanides have been compiled and compared.,, The values were obtained from published electrode potentials from linear plots of electron-transfer absorption band energy for various MIv complexes uersus respective (111)-(IV) potentials from linear plots of f+ d absorption band energies for various MI" complexes uersus respective (IIIHIV) potentials and from theoretical calculations using refined electron-spin-pairing-energy theory.The results suggest that the unknown oxidation levels Cf" EdV Fm'" and possibly Md" (in order of decreasing expectation) might be stabilized in various media, as might PmIV and Sm" from the lanthanides. The crystal structure of AmCI ,6H20 shows it to be [AmCl,(OH,),]Cl with the anions linking the cations by hydr~gen-bonding.~~ BkCI ,6H,O appears from its powder photograph to be isostructural. A refinement in the structure34 of AmCl (which has the UC1 type structure) gives the value 984(3) pm for the ionic radius of Am3 +.The crystal structure has also been determined for PaBr .35 This is isostructural with ThCl, and Pa-Br distances of 277 pm and 307 pm were determined setting the covalent radius of Pa" at 163 pm. The complex (Et4N)4[U(NCS)8] has been shown to contain a UN skeleton which is absolutely cubic within experimental error.36 The U-N bond lengths are 238 & 1 pm and each U-N-C-S unit is linear. The crystal structure of the first actinide phthalocyaninate bisphthalocyaninatouranium(rv) has also been reported.,' It too has UN8 co-ordination (U-N is 243 pm) but the two 2 9 J. R. Peterson J. A. Fahey and R. D. Baybarz J . Inorg. Nuclear Chem. 1971,33,3345. 30 M. I. Ermolaev Russ. J . Inorg. Chem.1970 15 383. 3 1 J. C. Mailen and L. M. Ferris Inorg. Nuclear Chem. Letters 1971 7 431. 32 L. J. Nugent R. D. Baybarz J. L. Burnett and J. L. Ryan J . Inorg. Nuclear Chem., 3 3 J . H. Burns and J. R. Peterson Inorg. Chem. 1971 10 147. 3 4 J. H. Burns and J. R. Peterson Acta Cryst. 1970 B26 1885. 3s D. Brown J. J. Petcher and A. J. Smith J . Chem. SOC. ( A ) 1971 908. 3 6 R. Countryman and W. S. McDonald J . Inorg. Nuclear Chem. 1971 33 2213. 37 A. Gieren and W. Hoppe Chem. Comm. 1971,413. 1971,33,2503 The Transition Elements 37 1 quadridentate ligands are staggered deviating only 8" from the square anti-prismatic structure. The phthalocyaninate ligands normally planar are in this compound saucer-shaped the outer edges bending away from the uranium atom and from the other ligand.Spectroscopic studies of uranium(1v) in LiF-BeF2 melts38 demonstrate the presence of the equilibrium UFg4- UF73- + F-. An examination of the temperature-dependent proton relaxation times of U'" hydrate in aqueous solution led to the conclusion that the co-ordinated water moleculesswere not all eq~ivalent.~ The compound UI,(CNR) (R = cyclohexyl) has been isolated.,' This is claimed to be the first complex containing uranium+arbon bonds with no other n-ligands. 50 mg-Scale reactions between americium-241 hydride and sulphur (or selenium) in sealed tubes over a period of one week with temperature gradients of 700-600 K allowed the isolation of samples of americium disulphide (or diselenide).,' Only the monosulphide or sesquisulphide were known pre-viously.The new compounds were characterized by crystallographic methods, and have the stoicheiometries AmS,. and AmSel.8. A series of fluorides and oxyfluorides of protactinium(v) (some previously known) have been obtained from the action of HF gas on Pa20,. PaF ,2H20 and PaF,,H,O are the products at 310 K and 320 K respectively whereas Pa20F8 is produced at 410K or in aqueous condition^.^^ When this latter compound is heated in air the products Pa0,F (at 560 K) Pa,O,F (at 840 K), and finally Pa,O (above 920 K) are formed successively. Pa,07F is isostruc-tural with high-temperature U308. Treatment of MX (M = Pa or U ; X = C1 or Br) with (Et,N)Cl or Ph,PO ( = L) in ethanol gives (Et,N)[M(OEt),X,] or M(OEt)2X3L.43 The derivatives PaOC13L2 and PaOBr,L result when the appropriate ethoxy-complexes and (Et,N)Cl or L are heated in MeCN containing 0.5% water.The compounds are of interest as they are the first reported com-pounds containing the protactinyl group Pa=O. Reactions in anhydrous MeCN produce MX,L . More reports on Uv compounds including the previously mentioned paper,43 leave the impression that this oxidation state is neither so rare nor so unstable as was once believed. Simpler preparations of UF6- and UCl,- and the prepara-tions of the new ions UBr,- and U16- have been described. The ions UOFS2-, UOCl,,- anu UOBrS2- are also novel., The stability of all these ions against disproportionation has been demonstrated in various non-aqueous media. The complexes UCI,L2 (L = py quinoline isoquinoline ct- or 0-picoline) have been prepared from UCl in SOC1 solution.45 3 8 L.M. Toth J. Phys. Chem. 1971 75 631. 3 9 V. A. Glebov Yu. D. Knyazev V. A. Lekae and N. N. Borodina Rum. J . Znorg. Chem., 1970 15 683. 40 F. Lux and U. E. Bufe Angew. Chem. Internat. Edn. 1971 10 274. 4 1 D. Damien and J. Jove inorg. Nuclear Chem. Letters 1971 7 685. 4 2 D. Brown and J. F. Easey J . Chem. SOC. ( A ) 1970 3378. 4 3 D. Brown and C. E. F. Rickard J . Chem. SOC. ( A ) 1971,81. 4 4 J . L. Ryan J . Inorg. Nuclear Chem. 1971 33 153. 4 5 R. C. Paul G. Singh and M. Singh J . Inorg. Nuclear Chem. 1971 33 713 372 R. J . Cross and J. M . Winjield As usual most work on Mvl complexes concerns uranium. The crystal structure of ethanol-[NN'-o-phenylenebis(salicylideneiminato)]dioxoura-nium(vr) shows it to be another seven-co-ordinate derivative with the uranyl oxygens perpendicular to the approximately planar pentagon of the UN203 atoms.46 The compound is made by condensing salicylaldehyde with o-phenyl-enediamine in the presence of U02C12 ,3H2/) or U02(N03)2 ,6H20 in ethanol.The co-ordinated ethanol molecule can be replaced by Ph,PO DMSO py or aniline. A neutron diffraction study4' on [UO,(NO,) ,2H20] gives a different result to those from previous X-ray work. The new study assigns four uranium atoms per unit cell and finds a hexagonal arrangement of oxygen atoms per-pendicular to the U 0 2 group. The six oxygen atoms derive four from the two (trans) nitrates and two from the water molecules. X-Ray studies on the orthorhombic P-UO2(OH) show that its thermal expansion between 300 K and 530 K is a n i ~ o t r o p i c .~ ~ Large contractions in a accompany large expansions in b while c undergoes a smaller cyclic change. Above 530 K the expansion is isotropic. These observations are interpreted in terms of a thermally induced rotation of the oxygen octahedra surrounding the uranium atoms. X-ray scattering from concentrated hydrolysed or acidified solutions of U02C12 indicates that the co-ordination number about uranium remains similar to crystal-structure values.49 Polynuclear compounds were detected in the hydrolysed solutions and uranium-uranium distances of ca. 386 pm suggest double oxygen bridges. Most of the polynuclear species contain only two or three U atoms and the dimers have structures similar to [(UO,),(OH),-C12(H20)4].The three U atoms of the trinuclear species are almost equilateral. Low-temperature n.m.r. studies on the solvation of U02(C104)2 U02(N03)2, and U02(C104)2 ,HCI in H20 DMSO and acetone at 173 K allowed direct observation of co-ordinated H 2 0 and DMSO." Surprisingly DMSO is preferentially bound (mode of co-ordination unknown) to U02* +- at the expense of water. The complexes { [CO(NH~)~]HSO~)~[N~O~(SO~),],~H~and {[Co(NH,),]HS04}2[Am02(S04),],nH20 prepared from [cO(NH&]3' and aqueous M022 + sulphates are isostructural with the uranium analogue.' There is little to report on MV" compounds this year. Li'NpO, Ba,(NpO&, Ba,NaNp06 and Ba&iNpO have been made from solid materials in similar manner to reactions described in past years.Powder diffraction data on all but the Ba derivative show them to be isomorphous with the corresponding Tcv" and ReV" derivative^.^^ 46 G. Bandoli D. A. Clemente U. G. Croatto M. Vidali and P. A. Vigato Chem. Comm., 1971 1330. 4 7 N. K. Dalley M. H. Mueller and S. H. Simonsen Inorg. Chem. 1971 10 323. 4 8 M. J. Bannister and J. C. Taylor Acta Cryst. 1970 B26 1775. 4 9 M. Aberg Acta Chem. Scand. 1970 24 2901. A. Fratiello V. Kubo and R. E. Schuster Inorg. Chem. 1971 10 744. 5 1 K. Ueno and M. Hoshi J. Inorg. Nuclear Chem. 1971,33 2631. 5 2 S. K. Awasthi L. Martinot J. Fuger and G. Duyckaerts Inorg. Nuclear Chem. Letters, 1971 7 145 The Transition Elements 373 The co-ordination chemistry and physical properties of the trans-plutonium actinides have been reviewed.53 4 The Titanium Group Titanium.-Although complex formation between TiC1 and Lewis bases has been studied for many years only recently has there been a significant attempt to obtain any quantitative data on donor strength^.'^.^^ The measurement of condensed-phase heats of formation of TiC1,L and TiC1,L2 (L = organic N-, 0- or S-donor ligand) complexes and of their heats of sublimation has enabled gas-phase heats of formation to be calculated.They are in the range 108-178 kJ mol- ' (1 1 complexes assumed to be monomeric) and 175-246 kJ mol- ' (1 2 complexes) and indicate that tetrahydrofuran and benzophenone are strong ligands tetrahydrothiophen and acetophenone are moderately strong while acetonitrile is a weak ligand towards TiC14.54" This work gives further support to the notion that do transition-metal chlorides are 'softer' than might be ex-pected (see also ref.84). In similar POCI has been shown to be a weak donor to TiCl,. The condensed-phase heats of formation of TiC1,L and TiCl,L, are 73.5 and 87-0 kJ mol-' respectively both complexes being completely dis-sociated in the gas phase. 1,4,5-Trimethyltetrazaboroline (1) and related com-pounds form adducts (2TiC14,1.5L) with TiCl, for which L-bridged polymeric N=N I I MeN ,NMe B Me structures are suggested. In the presence of aromatic hydrocarbons coloured complexes 2TiC1 ,L,ArH or 2TiC1 ,L,O.SArH are formed and their condensed-phase heats of formation (265-283 kJmol-') suggest that ArH is not incorporated into the lattice simply as occluded solvent.55 An attempt to co-ordinate an ally1 group to TiCl, via complex formation with o-allylaniline (L) was not successful and five-co-ordinate TiC1,L was formed,56 but the Ti-C a-bond appears to be stabilized in complexes of MeTiC1 with N- P- 0- or S-donor ligands." Further work on complex formation between TiCl and tertiary phosphines L = PMe,Ph PMe, or PBun3 has appeared in 5 3 B.B. Cunningham Pure Appl. Chem. 1971 27 43. 5 4 ( a ) B. Hessett and P. G. Perkins J . Chem. SOC. ( A ) 1970 3229; (b) ibid. p. 3331. 5 5 B. Hessett J. H. Morris and P. G. Perkins J . Chem. SOC. ( A ) 1971 2056 2466. 5 6 5 7 G. W. A. Fowles D. A. Rice and J. D. Wilkins J . Chem. SOC. ( A ) 1971 1920. D. A. Baldwin and R. J. H. Clark J . Chem. Sac. ( A ) 1971 1725 374 R. J .Cross and J . M . Winfield particular a 'H and 31P n.m.r. study.,' This indicates fast equilibria in solution between trigonal-bipyramidal (C3J TiC1,L (cf. last year's Report) octahedral (C2J TiCl,L, and free L. There is some evidence for the existence at low tem-peratures of a dinuclear species formulated as [C1,TiCl,TiCl3L]. The products obtained from the PC1,-TiCl system which depend on the solvent used have been characterized by X-ray ~rystallography.~~ From POC13 solution [PCl,],-[Cl,TiCl,TiCl,] is obtained while [PCl,] [Cl,TiCl,TiCl,] is the product in SOCl solution when either PCl or PCl is used as the source of PCl,'. The face-sharing di-octahedral configuration of the latter anion is unusual for a 3d element (cf. 1968 Report). The complexes Ti(acac) (OR) for which five-co-ordinate structures had been previously suggested have been shown6'' to be mixtures of Ti(OR) and Ti(acac),(OR) .Attempts to prepare Ti(acac)X (X = halide) result in similar mixtures being formed and the dimeric intermediate [(acac),TiX,TiX,] is suggested. Five-co-ordination is claimed for Ti(PhCOCH-CO.Ph)Cl from i.r. molecular weight and conductometric work but its n.m.r. spectrum suggests that the equilibrium 2Ti(biX)Cl Ti(biX),Cl + TiCl exists in solution.60b A further n.m.r. study of the molecular rearrangements in cis-Ti(biL)(OR), (biL = acac oxine or 2-methyloxine ; R = substituted phenyl group) compounds has been reported.61 The rate of rearrangement increases with decreasing pK, of the parent phenol and the processes are characterized by large negative entropies making a trigonal twist mechanism unlikely.A transition state re-sembling a tightly bound ion pair is suggested the rearrangement occurring via anion migration across the surface of the complex cation followed by collapse of the ion pair. The lability of Ti(acac),X and of TiCl,L (L = dimethylforma-mide) is illustrated also by the induction of optical activity in these compounds by the addition of an optically active centre e.g. (+)-tartaric acid.62 Other work on Ti" compounds is mentioned in the Ligands section. Lower oxidation states have received little attention this year. Analogies between Ti"' and Cu" have been drawn from an e.s.r. study of Ti"' complexed with carboxylic and substituted benzoic acids and related compounds. Signals attributed to dimeric species were observed and structures suggested.The Ti -Ti distances deduced vary from 470 pm (mandelato-complex) to 860 pm (8-hydroxyquinola to-complex). Zirconium and Hafnium.-Work on these elements this year has been almost entirely crystallographic. Interest in non-rigid compounds (see under Ti) has resulted in a structure determination on Zr(a~ac),Cl.~ The molecule has a 5 8 5 9 T. J. Kistenmacher and G . D. Stucky Znorg. Chem. 1971 10 122. 6 o (a) C. E. Hollowayand A. E. Sentek Canad. J . Chem. 1971,519; (b) D. W. Thompson, 6 1 J. F. Harrod and K. Taylor Chem. Comm. 1971 696. 6 2 V. Doron W. Durham and D. Frazier Znorg. Nuclear Chem. Letters 1971 7 91; 6 3 T. D. Smith T. Lund and J. R. Pilbrow J . Chem. SOC. ( A ) 1971 2786.6 4 R. B. VonDreele J. J. Stezowski and R. C. Fay J . Amer. Chem. SOC. 1971 93 2887. F. Calderazzo S. A. Losi and B. P. Susz Helt;. Chim. Acta 1971,54 1156. R. W. Rosser and P. B. Barrett Inorg. Nuclear Chem. Letters 1971 7 931. V. Doron and W. Durham J . Amer. Chem. Soc. 1971 93 889 The Transition Elements 375 distorted pentagonal-bipyramidal configuration with the C1 atom axial and Zr-O(axia1) ca. 6 pm shorter than the average Zr-O(equatoria1) distance of 214 pm. Rb,Zr,F21 features cross-linked chains of Zr -F polyhedra containing seven- eight- six- and seven-co-ordinated Zr atoms. The respective polyhedra are a pentagonal bipyramid an irregular antiprism an octahedron and an irregular antiprism with one corner rem~ved.~' Eight-co-ordinate Hf is present in HfF ,3H,O which is [F2/2F,Hf(H20),F,I,],(H20)m.Although the crystal structure is different from that of the Zr analogue the stereochemistry of the two metals is similar.66 Zr%ulphate compounds continue to attract attention and the structures of A,Zr(S0,)3 ,xH,O (A = Na x = 3; A = K x = 2) reported this year both contain dodecahedrally co-ordinated Zr.67 They differ in that the Na' salt has a spiral structure [Zr(S0,),(S0,)2,2(H20)2]m while the K+ salt contains [(SO,),-(H20),Zr(S04)2Zr(H,0),(S04)2] units. Both structures are closely related to those of the hydrated binary sulphates. A compound formulated as Na,[Zr,Cr,-(S04)4(OH),,],6H20 has been suggested as a model compound to study the binding of transition-metal complexes to proteins and peptides and also as a tanning agent.68 5 The Vanadium Group Oxidation potentials and other thermodynamic data for compounds of V Nb, and Ta have been reviewed.69 Vanadium.-Several papers this year have dealt with the properties of compounds containing V 0 2 + and V 0 3 + groups.cis-Configurations (OVO = 104-107") have been established for the VO groups in [V0,(0x),]~ - and [VO,(quadriX)]"-(quadriX = H,edta or edta n = 1 or 3) complexes by X-ray V-0 distances are in the range 162.3-165.7 pm implying substantial double-bond character and bonds trans to V=O are characteristically lengthened. The general picture is very similar to that for other do complexes containing MO groups. X-ray studies have shown also that V=O groups are present in [VO(NO,),-(NCMe)] and (NH4)4[O{VO(02)2)2].71 In the former compound the terminal 0 and MeCN ligands occupy axial positions of a distorted pentagonal bipyramid, and the equatorial plane comprises a unidentate and two bidentate NO3 - ligands.It is claimed that uni- and bi-dentate NO3- groups can be distinguished in the compound's vibrational spectrum.71a The V atoms in the latter compound have a similar configuration and are linked by a non-linear 0x0-bridge in the equatorial plane.71b C4v Symmetry is suggested for the VOF,- anion in solid CsVOF,, b 5 b 6 D. Hall C. E. F. Rickard and T. N. Waters J . Znnorg. Nuclear Chem. 1971 33 2395. 6 7 I. J. Bear and W. G. Murnrne Acta Cryst. 1971 B27 494; W. G. Murnrne ibid. p. 6 8 K. C. Montgomery and J. G. Scroggie Austral. J. Chem. 1971 24 687. 6 9 J. 0. Hill I.G . Worsley and L. G . Hepler Chem. Rev. 1971 71 127. 7 0 W. R. Scheidt Chun-che Tsai and J. L. Hoard J . Amer. Chem. SOC. 1971 93 3867; W. R. Scheidt D. M. Collins and J. L. Hoard ibid. p. 3873; W. R. Scheidt R. Countryman and J. L. Hoard ibid. p. 3878. 7 1 (a) F. W. B. Einstein E. Enwall D. M. Morris and D. Sutton Inorg. Chem. 1971, 10 678; (b) I.-B. Svensson and R. Stomberg Acta Chem. Scand 1971. 25 89R G. Brunton Acta Cryst. 1971 B27 1944. 1373 376 R. J . Cross and J. M. Winjield but from its I9F and "V n.m.r. spectra in anhydrous HF a rapid rearrangement between C, and CZv environments is postulated in Eight-co-ordinate Vv is postulated in complexes containing the [V(0,),(ox)l3 - or [V(O,),-(biL)]- (biL = phen or bipy) groups.73 V 0 2 + complexes commonly have square-pyramidal configurations but the alternative trigonal-bipyramidal geometry is featured in two papers this year.74 V0(2-methyloxine) has been shown to have this structure from X-ray work, with N atoms in axial positions.There is a significant deviation from CZv sym-metry owing to the V=O group. 74a Trigonal-bipyramidal geometry is favoured for the complexes VOCl,(PR,) which were identified in solution from their e.s.r. spectra.74b A magnetochemical study of VO(quadriX) in which quadriX = NN'-propylenebis(salicylaldimine) whose structure was reported last year has shown that it obeys the Curie-Weiss law over the range 95-295 K. The V=O. V bridges provide little or no antiferromagnetic coupling and it is suggested that the spin exchange in VO(OAc) and related compounds occurs uia the carboxylato-groups.75 Variation in magnetic properties is also illustrated by complexes between V 0 2 + and Schiff bases derived from 2-aminothiophenol and substituted salicylaldehydes or 2-hydroxynaphthaldehyde.These ligands function either as terdentate 0-,N-,S-donors giving VO(terX),nH,O n = 0 or 1 or as bidentate 0-,N-donors giving VO(biX) . While the latter compounds have normal mag-netic moments the former have low moments peff = 1-27-1.28 B.M. at room temperature and their magnetic properties are consistent with antiferromagnetic exchange.76 E.s.r. spectroscopy has proved to be a useful tool for investigating the solution equilibria of V 0 2 + complexes and the behaviour of a-hydroxy- and a-mercapto-carboxylic acids (H2X) towards V 0 2 + has been investigated by this technique.Although similar species are formed in both systems e.g. VO(X) and cis- and tr~ns-VO(X),~ - formation constants for the thio-complexes are smaller and the protons of these complexes are more Reactions between V 0 2 + salts and substituted 1,2-dihydroxybenzenes, biX = [R-C6H302]2- have been carried out in an attempt to study the cis-effect of equatorial ligands on the VO group in VO(biX),. Tl,[VO(biX),] or T1,-[V(biX),] are formed depending on the nature of R. The former type is favoured by the electron-withdrawing substituent R = CHO while the latter is formed when R = H 3-Me 4-Me or 3-Me0.78 V(S,CR) have been prepared from similar reactions. The presence of eight-co-ordinate VIV is inferred from their i.r.spectra and this has been confirmed by X-ray work for R = PhCHz-.79 VCl has been used as a probe to investigate the surface structure of oxides such as Al,O and SiO,. The stoicheiometry of its reaction with -OH groups is 7 2 J. A. S. Howell and K. C. Moss J . Chem. SOC. ( A ) 1971,270. 7 3 J. Sala-Pala and J. E. Guerchais J . Chem. SOC. ( A ) 1971 1 1 32. 7 4 ( a ) Motoo Shiro and Q. Fernando Chem. Comm. 1971 63; ( b ) G. Henrici-Olive and S. Olive J . Amer. Chem. SOC. 1971 93 4154. 7 5 D. M. L. Goodgame and S. V. Waggett Inorg. Chim. Acta 1971 5 155. 76 C. C. Lee A. Syamal and L. J. Theriot Znorg. Chem. 1971 10 1669. 7 7 R. R. Reeder and P. H. Rieger Znorg. Chem. 1971 10 1258. '' R. P. Henry P. C. H. Mitchell and J. E. Prue J . Chem. SOC. ( A ) 1971 3392.7 9 0. Piovesana and C. Furlani Chem. Comm. 1971 256; M. Bonamico G. Dessy, V. Fares P. Porta and L. Scaramuzza ibid. p. 365 The Transition Elements 377 determined by HC1 evolution and the geometrical arrangement of the groups has been determined by e.s.r. spectroscopy." Transmission of substituent effects in B-diketonate complexes has been studied by n.m.r. work on V(biX),(biX') com-plexes in which biX biX' = acac or its substituted derivatives V"' being chosen because of its short electron-spin relaxation time. The contact shifts are interpre-ted on the basis of ligand +- metal charge transfer but are opposite to expectation, in that electron-withdrawing substituents decrease charge transfer to the substi-tuted ligands and increase it to the rest. It is suggested that an electron-withdraw-ing ligand in the xy plane populates d X y .This cannot interact with the n-system of the xy ligand but can interact with the remaining ligands. This behaviour should be typical for metals with unsymmetrically filled t2n sub-shells.8 The complexes VX,L [X = Br or C1; L = Et,S or HC(C,H,),N (quinucli-dine)] for which trigonal-bipyramidal trans-structures are formulated have been described.82 VX,(SEt,) exists in equilibrium with a six-co-ordinate complex in Et,S solution whereas only six-co-ordination is observed in the analogous Cr"' system. Further mapping of V" chemistry83 has characterized A'[V(H,O),]-Cl NH,[VCI,(H,O),] and Cs,[VCl,(H,O),]. The latter two compounds are magnetically dilute and their electronic spectra show moderate deviation from Oh symmetry.Anhydrous AVC1 (A = Rb or Me,N) are strongly antiferro-magnetic and their spectra contain intense spin-forbidden bands. Niobium and Tantalum.-As usual halogeno-ligands occupy a prominent place in the published chemistry of these elements. Some aspects are reported below, and other work is reported in the Ligands section. The stability constants of MC1,L (L = RCN R 2 0 or R2S) complexes have been determined by an n.m.r. spectroscopic method enabling some comparison of donor-acceptor behaviour to be made.84 Electronic factors are considered to be most important in deter-mining the stability of nitrile complexes whereas in ether and sulphide complexes steric effects are more important. The complexes MCl,,SR are more stable than MCl,,OR, in agreement with previous preparative work (see also Ti section).NbCl is a weaker Lewis acid than TaCl towards R,O and RCN and exhibits 'softer' behaviour. Aminolysis reactions of NbOBr which from its i.r. and n.q.r. spectra appears to have a structure similar to NbOCl, give NbOBr,(NHR) NbOBr,(NR,),NHR (R = Et Bun or CsH1,) and NbOBr-(NEt,) with primary or secondary amines. 1 1 Complexes are formed with tertiary a m i r ~ e s . ~ ~ Recent interest in dialkyldithiocarbamate complexes of these elements has occasioned X-ray work on [NbX(OMe),(S,CNEt,),] X = C1 or Br.86 Nb is seven-co-ordinate in a pentagonal-bipyramidal configuration with axial OMe groups. Nb-S distances are in the range 2 5 6 2 6 2 pm. ' O J. C. W. Chien J. Amer. Chem. SOC. 1971 93 4675. 8 2 8 3 L.F. Larkworthy K. C. Patel and D. J. Phillips J. Chem. Soc. ( A ) 1971 1347. 8 4 A. Merbach and J.-C. Bunzli Chimia (Switz.) 1971 25 222. 8 5 Yu. A. Buslaev S. M. Sinitsyna V. I. Sinyagin and M. A. Polikarpova Russ. J. 8 6 J. W. Moncrief D. C. Pantaleo and N. E. Smith Inorg. Nuclear Chem. Letters 1971, D. R. Eaton and K. L. Chua Canad. J. Chem. 1971,49 56. R. J. H. Clark and G. Natile Inorg. Chim. Acfa 1970 4 533. Inorg. Chem. 1970 15 1204. 7 255 378 R. J . Cross and J. M . Winjield The paucity ofgood synthetic routes to lower oxidation states of these elements (apart from metal cluster compounds) means that their chemistry is relatively unexplored. Three recent papersg7 have described the reduction of NbV to Nb"'. Electrolytic reduction of NbCl and bipy [presumably present as NbC1,-(bipy)] in ROH leads to paramagnetic Nb,Cl,(OR),(bipy) .87a A similar reduc-tion of NbCl in EtOH under nitrogen and in the presence of a small quantity of HCI gives a solution containing Nbl" from which a Nb"'-lactato-complex is isolated on the addition of lactic The preparation of stoicheiometric NbF has been claimed (previous claims to have isolated this compound have been shown to be incorrect) from the reaction of NbF with Nb at high temperature and pressure.It has the ReO structure is a semiconductor and is weakly paramagnetic.* A series of superconducting intercalation complexes between TaS and py or its substituted derivatives have been described.88 Their critical temperatures vary between 1.5 and 4.5 K and generally increase as the number of intercalated molecules per TaS increases.Both TaS and the organic molecules retain their identity and the size and basicity of the latter determine whether intercalation occurs. The basicity is probably responsible for the dependence of critical temperature on the number of molecules intercalated. 6 The Chromium Group Chromium.-Little information is available about the aqueous chemistry of this element in its tetrapositive state. In an attempt to remedy this situation the reduction of Cr"' under various conditions has been studied. Indirect evidence for the following reactions of Cr" in acidic solution was obtained :89 2Cr" -P Cr"' + CrV; Cr" + CrV1 -+ 2Cr"; Cr" + e + Cr"' ; and Cr" + nL -P CrL,. Once again the tripositive state provides a microcosm of the activity in transi-tion-metal co-ordination chemistry.CrCl,(s) is chemically transported by gaseous Al"' chloride in a temperature gradient 773 -+ 673 K via a complex formulated as Cr(CI,AlCl,) .90 Further work on PCI ,CrC1 has not substantiated a previous suggestion that the complex contains tetrahedral CrC1,- anions. An octahedral CrCI chromophore is indicated from its electronic spectrum.' Absolute configurations of several [Cr(biX),] complexes have been determined by X-ray ~rystallography.'~ The species concerned are A-( +),,,-trans-[Cr(( +)-3-acetyl-camphorato) ,I A-( + ) g ,-[Cr(malonato),] - and A-( +)s g 9-[Cr(o~),]3 - and the configuration of the second species is opposite to that assigned from spectroscopic *' (a) C . Djordevic and V.Katovic J . Chem. SOC. ( A ) 1970 3382; (b) R. Bosselaar B. G. van der Heyden and R. Mieras Inorg. Nuclear Chem. Letters 1971 7 1199; ( c ) M. Pouchard M. R. Torki G. Demazeau and P. Hagenmuller Compt. rend. 1971, 273 C 1093. 8 8 F. R. Gamble J. H. Osiecki and F. J. DiSalvo J . Chem. Phys. 1971,55 3525. 89 G. P. Haight jun. T. J. Huang and B. Z . Shakhashiri J . Inorg. Nuclear Chem. 1971, 90 K. Lascelles and H. Schafer Z . anorg. Chem. 1971 382 249. 9 1 J. H. J. Dawson and D. W. Smith Inorg. Nuclear Chem. Letters 1971 7 81 1. 9 2 33 2169. W. Dew. Horrocks jun. D. L. Johnston and D. MacInnes J . Amer. Chem. Soc., 1970,92 7620; K. R. Butler and M. R. Snow Chem. Comm. 1971 5 5 0 The Transition Elements 379 work. X-Ray work has shown that [Cr(salen)(H,O),]Cl has an octahedral trans-structure.This and related Cr"'sa1en complexes show approximate Curie-Weiss magnetic behaviour with high-temperature deviations characteristic of tem-perature-independent paramagnetism. The behaviour of [Cr(salen) (OH)],nH20, n = 0 or 0.5 however indicates antiferromagnetic exchange.93 Dinuclear ligand-bridged Cr"' compounds have been the subject of several reports. X - R ~ Y S ~ ~ indicates non-linear CrOCr bridges in [(NH,),Cr(OH)-Cr(NH,),]" ( C r O x = 154" Cr-0 = 200pm) and in [(NH,),Cr(OH)Cr-(NH3)4(H20)]5 + (CrOCr = 168 f So). In the analogous 0x0-complex [(NH3),-CrOCr(NH3),]4f the Cr-0-Cr bridge is linear the Cr-0 distance (182.1 pm) is rather short and the -Cr(NH,) units have an eclipsed configuration. The structure is consistent with the weak paramagnetism previously observed ; sharp doublet bands in its electronic spectrum95 are believed to be due to simultaneous pair excitation at both Cr"' centres (cf.analogous work on Fe"',O compounds last year). Ion-exchange techniques have been used to prepare Cr"' complexes with protonated polyamine ligands for example the series of cations [Cr(tetrenH,)-(H20)"+ (tetren = tetraethylenepentamine n = 0 4 ) have been charac-terized in solution96 starting from [Cr(tetren)Cl]' +. [Cr(NH3),{OP(OEt)3}]3 +, which is conveniently prepared from [Cr(NH3),N3l2+ and NO +C104- in (EtO),PO has been suggested as a useful reagent to prepare other [Cr(NH3),LI3+ complexes where L is a weak ligand.97 The ,E-+ 4A2 phosphorescence is observed when [Cr(en),l3+ or [Cr(NH3)6I3+ are excited by a He-Ne laser either in the solid state or in aqueous solution at 298 K.The solution work is of interest, as although photochemical reactions of Cr"' are believed to involve the 2 E state, it has been supposed that rapid quenching of this state in solution would preclude the observation of phosphorescence. Decomposition in the laser beam leads to aquation in solution and to replacement of NH3 ligands in [Cr(NH3),I3+ by counter-ions in the solid state.98 Work on lower oxidation states has been concerned with the nature of the metal-ligand bond. Restricted rotation of alkyl groups in [Cr(biL),I2+ (biL = alkyl-substituted phen) complexes observed by H n.m.r. spectroscopy is believed to be due to electronic rather than to steric effects and indicates signifi-cant n - b ~ n d i n g .~ ~ A synergic picture of the bonding in [Cr(bipy),]"+ (n = 0-3) also emerges from an i.r. spectroscopic study. The Cr-N stretching frequencies, 93 P. Coggon A. T. McPhail F. E. Mabbs A. Richards and A. S. Thornley J. Chem. 94 A. Urushiyama T. Nomura and M. Nakahara Bull. Chem. SOC. Japan 1970 43, 9 5 E. Konig Chem. Phys. Letters 1971 9 31. 96 Soc. ( A ) 1970 3296. 3971 ; M. Yevitz and J. A. Stanko J . Amer. Chem. SOC. 1971,93 1512. S. J. Ranney and C. S. Garner Synth. Znorg. Metal-org. Chem. 1971,1 179; S . C. Tang, R. L. Wilder R. K. Kurimoto and C. S. Garner ibid. p. 207; R. L. Wilder D. A. Kamp and C. S. Garner Znorg. Chem. 1971 10 1393. 9 7 E. A. Hosegood and J. L. Burmeister Synth. Znorg. Metal-org. Chem.1971 1 21. 9 8 S. L. Barker Chem. Comm. 1971,363; T. V. Long jun. and D. J. B. Penrose J. Amer. 9 9 G. N. La Mar and G. R. Van Hecke Chem. Comm. 1971,274. Chem. SOC. 1971,93 632 380 R . J . Cross and J . M . Winfield assigned with the aid of "Cr and 53Cr isotopic enrichment studies (cf. last year's Report) vary little with change in n. This suggests that there is little change in Cr-N bond strength and that in this type of complex oxidation states have dubious significance. loo Molybdenum and Tungsten.-Values for the electron affinity of WF, and the F-ion affinity of WF, of 502 k 21 and 606 k 25 kJ mol- ' respectively have been calculated from a heat of hydrolysis determination on KWF,. Previous esti-mates of the electron affinities of 5d hexafluorides are reasonably consistent with the value obtained here."' The two products from the oxidation of WCl by CCl,CN(reported last year) have beenshown by X-ray work to contain C2Cl,N= groups.Their structures are [(C,Cl,N)CI WC12WCl,(NC2CI,)] and [CCl,-CNWCI,NC,Cl,] and each contains distorted octahedrally co-ordinated tungsten. The short W-N distances (171 and 170 pm respectively) and almost linear W -N-C skeletons suggest triple-bond character in the C,Cl,N-W linkage.'02 Complexes between WS4,- and dipositive 3d-metal ions have been reported and [M(WS,),]'- M" = Co Ni or Zn (square-planar Ni" being indi-cated from the complex's spectral and magnetic proper tie^),"^ and complexes between WCI and the ligands L = Ph,PX (X = S or Se) which are formulated as [C14WL2WCl,]CI, have been described.lo4 Several papers have been concerned with the stereochemistry of eight-co-ordinate complexes of these elements in their tetrapositive states.A laser Raman spectroscopic study of K4M(CN),,2H20 in the solid state and in aqueous solution has suggested that the anions have D 2 d symmetry in both phases, contrary to previous work. Accurate depolarization ratios were obtained from the solution spectra and the number of totally symmetric modes exceeds that required for D4d ~yrnmetry.'~' Complexes of the type W(biX) (biX = substi-tuted oxine) which are conveniently prepared from W(CO) or K,W,CI and HbiX are of interest ' 0 6 because they contain both n-donor (0) and n-acceptor (N) ligand atoms. In an ML,L' (M = d' or d 2 ion) complex of D 2 d symmetry the n-acceptor (L') ligands should form a flattened tetrahedron near the plane of the empty d, orbital and diagonal to the occupied d,2-,,2 orbital while n-donor or n-non-bonding ligands (L) should form an elongated tetrahedron beyond the d,, d, maxima towards the z-axis.This treatment originally due to Orgel has received experimental support from the structure of W(5-bromo-oxine) de-termined using X-ray crystallography in which the W04N4 group has the arrangement described above.106a l o o J. Takemoto B. Hutchinson and K. Nakamoto Chem. Comm. 1971 1007. l o ' J. Burgess I. Haigh and R. D. Peacock Chem. Comm. 1971 977. l o ' M. G. B. Drew G. W. A. Fowles D. A. Rice and N. Rolfe Chem. Comm. 1971,231; M. G. B. Drew K. C . Moss and N. Rolfe Znorg. Nuclear Chem.Letters 1971 7 , 1219. l o 3 A. Muller E. Diemann and H.-H. Heinsen Chem. Ber. 1971 104 975. ' 0 4 P. M. Boorman and K. J. Reimer Canad. J . Chem. 1971,49 2926. l o 6 ( a ) W. D. Bonds jun. R. D. Archer and W. C . Hamilton Znorg. Chem. 1971 10, T. V. Long jun. and G . A. Vernon J . Amer. Chem. SOC. 1971 93 1919. 1764; (6) W. D. Bonds jun. and R. D. Archer ibid. p. 2057 The Transition Elements 38 1 Compounds in which there is the possibility of metal-metal interaction continue to be studied for example the interaction appears to be appreciable in [(py)2Cl,WCl,WCl,(py),] which is diamagnetic and has W-W = 273.7 prn."' Reactions between (Mo,X,)X and molten HgY (x Y = c1 Br or I) give Hg(Mo,X,)Y or Hg(Mo6Y8)Y,. The products are thermodynamically con-trolled; for example a heavier halogen in (Mo,X,) is always substituted by a lighter one.Hg(Mo,CI,)Cl contains regular [(MO&18)C1,]2- anions and has the NaCl structure.lo8 An interesting development in this area is the report of aquated lower-oxidation-state Mo cation^."^ [MO(H,O)~]~+ is prepared by the aquation of MoCl, - in aqueous trifluoromethanesulphonic or toluene-p-sulphonic acids by making use of the extreme non-ligating properties of these sulphonate anions (see Ligands section). The solutions are initially pale yellow but become green on standing possibly owing to the formation of condensed species. Aquation of K,Mo2(S04), which is formed from K,Mo,Cl ,2H,O and K,SO, in the presence of CF,SO,- under similar conditions gives an aquated species whose electronic spectrum resembles that of Mo,C~,~-.The species is very strongly held on a cation-exchange column and is oxidized by Fe3+ to MoV1. It is suggested that it is Mo,,+(aq). Both of these species have great potential for use in redox reactions. A further example of a six-co-ordinate trigonal-prismatic complex has been characterized by X-ray work. Mo(Se,C,(CF,),} has overall C3 symmetry with a D, MoSe arrangement. The Se-Se distances (322.2 pm) are relatively short and it is suggested that the trigonal-prismatic geometry is stabilized by inter-donor-atom interactions.' 'O Complexes of Mo with dinitrogen continue to attract interest.' ' Reduction of green [MoOCl,(diphos)(THF)] (THF = tetrahydrofuran) with Zn under N2 gives trans-[Mo(N,),(diphos),] which is also prepared from Na-Hg reduction of MoCl,(diphos) or MoCl,(diphos) and a compound formulated as [MoCl,(N,)-(diphos),].The latter compound reacts with MoCl,(THF) to give a blue solid which appears to be a dinitrogen-bridged dinuclear species. This would be analogous to the Re-N,-Mo compounds reported last year. Molybdenum and Tungsten 0x0-compounds.-Work in this area has a strong stereochemical bias. Compounds containing cis-MO groups that have been characterized by X-ray crystallography include (MoO,CI(DMF),} ,O (DMF = dimethylformamide) K2[MoO,(C,H,0,),],2H2O and AMoO,F, (A = NH,, K or Rb).' l 2 The latter anion is polymeric [MoO,F,F,,,] with cis F-bridges trans to 0 whereas asymmetric 0x0-bridges are found in K[MoO(O),,,-l o ' R. B. Jackson and W. E. Streib Inorg.Chern. 1971 10 1760. l o ' H. Lesaar and H. Schafer Z . unorg. Chem. 1971 385 65; H. G. von Schnering ibid., l o 9 A. R. Bowen and H. Taube J . Amer. Chern. SOC. 1971,93 3287. 1 1 1 p. 75. C. G. Pierpont and R. Eisenberg J . Chern. SOC. ( A ) 1971 2285. L. K. Atkinson A. H. Mawby and D. C. Smith Chern. Cornm. 1971 157. L. 0. Atovmian J. A. Sokolova and V. V. Tkachev Dokludy Akud. Nuuk S.S.S.R., 1970,195,1355; L. 0. Atovmian 0. N. Krasochka and M. Ya Rahlin Chern. Comm., 1971 610; L. 0. Atovmian and 0. N. Krasochka Dokludy Akud. Nuuk S.S.S.R., 1971 196 91 382 R . J . Cross and J . M . WinJield Cl2(H,O)J3C1. MOO undergoes chemical transport by I in a temperature gradient of 1273-1073 K and a thermodynamic study suggests that MoO,I, exists in the vapour state under these conditions.' l 3 Non-rigid behaviour in solution is indicated for ~~s-[MoO,(M~,CCO~CHCOCM~,)~] from its 'H n.m.r.spectrum.'14 N.m.r. spectroscopy has been used to identify in solution the di-nuclear anions [OF4MFMF40]- (M = W or Mo) in which the 0 atoms are trans to the bridging F atom.'" The results obtained from a high-temperature (ca. 1673 K) electron-diffraction study of gaseous W03 can best be reconciled with a six-membered ring structure [W0202,2]3 in which the average W-0 distance is 117 prn.'l6 A stepwise aggregation mechanism for the formation of the ion [W,01,(OH)3]5- uia the tetratungstate ion (see 1969 Report) has been formulated. One of the two struc-tures which are proposed for the former ion is closely related to that of Mo,O,,~-, which is formed under similar conditions.'17 X-Ray work has shown that the diperoxoheptamolybdate ion in K [ M O O ~ ( ~ ~ ) ~ ] ~ H ~ ~ is derived from M070246- by the replacement of 0 at each end of the anion with 02,- giving two seven-co-ordinate Mo atoms.In K4[Mo4012(02),] however all the Mo atoms are in a distorted octahedral environment with each 02,- group being co-ordinated to all four Mo atoms. It is claimed"* that this is a new type of ligation for 02,-. In two reports' l 9 on mixed MoV'-MoV compounds co-ordination numbers of less than six are featured. Although the structure of Nao.gM06017 is basically of the ReO type it contains localized Moo4 tetrahedra which are associated with the Na atoms. MoV species having approximate C4" symmetry have been detected in an e.s.r.study of partially reduced Bi-Mo oxide catalysts (cf. last year's Report). Interest in the reactions of MoV with amino-acids and their derivatives has resulted in further X-ray work on these complexes.'20 Their structures are [(terX)(O)MoO,Mo(O)(terX)] terX = L-histidinate and [(biX)(O)Mo(O or S),-Mo(O)(biX)] biX = L-cysteinate alkyl ester. Mo occupies a distorted trigonal-bipyramidal environment in the latter compounds and the Mo-Mo distances for the Mo0,Mo and MoS,Mo bridges are 256.2 and 280.4pm respectively. A Mo0,Mo bridge is believed to be present in a Mo"'-edta complex which is formed on electrolytic reduction of the corresponding MoV compound. The H. Oppermann Z. anorg. Chem. 1971 383 285. T. J. Pinnavaia and W. R. Clements Znorg.Nuclear Chem. Letters 197 1 7 1 127. W. McFarlane A. M. Noble and J. M. Winfield J. Chem. SOC. ( A ) 1971,948; Yu. A. Buslaev Yu. V. Kokunov V. A. Bochkareva and E. M. Shustorovich Doklady Akad. Nauk S.S.S.R. 1971 201 355. '16 I. Hargittai M. Hargittai V. P. Spiridonov and E. V. Erokhin J . Mol. Structure, 1971 8 31. R. Stomberg L. Trysberg and I. Larking Acra Chem. Scand. 1970,24 2678. B. M. Gatehouse and D. J. Lloyd Chem. Comm. 1971 13; L. Burlamacchi G. Martini, and E. Ferroni Chem. Phys. Letters 1971 9 420. I 2 O L. T. J . Delbaere and C. K. Prout Chem. Comm. 1971 162; M. G. B. Drew and A. Kay J. Chem. SOC. ( A ) 1971 1846 1851. ' K.-H. Tytko and 0. Glemser Z. Naturforsch. 197 1 26b 659 The Transition Elements 383 compound is diamagnetic indicating antiferromagnetic exchange or direct bonding between the Mo atoms and is a good reducing agent.',' The complexes [MoOCl,(PR,),] which were reported last year exist as blue or green solids suggesting the possibility of isomerism.X-Ray work has shown that both blue [MoOCl,(PMe,Ph),] and green [MoOCl,(PEt,Ph),] have cis,mer-configurations. The two compounds have different bond lengths and angles, and this suggests that the blue and green series are due to distortional isomerism in the cis,mer-configuration. 122 7 The Manganese Group Manganese.-Complex halides of manganese in its lower oxidation states commonly have polymeric structures ; for example K,MnF ,H,O and K2MnF,SO4 whose structures have been reported this year,', contain [MnF,F,,,] and [MnF2F2,2(S04)2,2]a trans-bridged units.The 'two short and four long' distortion from octahedral co-ordination which is found in the latter compound is opposite to that normally found for high-spin Mn"' and is con-sidered to arise from the doubly bridged structure. In contrast the presence of discrete MnClS2- anions in [bipyH,] [MnCl,] has been confirmed by X-ray work. The anion is approximately square-pyramidal with Mn-Cl(ax) = 258-3 pm and the average Mn-Cl(equatoria1) = 230.2 pm.' 24 The single-crystal polarized electronic spectrum of this compound has been analysed on the basis of CZv symmetry at Mn while C4" symmetry is indicated from the spectrum of Mn"' doped into (Et,N),InC1,.'25 More work on Mn cyano-complexes has been reported. The structure of Mn" [Ru(CN),],8H20 is similar to that of Mn,[Co(CN),],,xH,O (reported last year) in that discrete ions are absent.The compound features distorted octahedral [RU(CN),] and fuc-[Mn(NC),(H,O),] groups the latter forming dinuclear units via two H,O bridges. The groups are linked by Ru-C-N-Mn bonding.',, An e.s.r. study has shown that two processes occur when [Mn(CN),N0I3-, doped into alkali-metal halides undergoes y-irradiation. One is the formation of [Mn(CN),NO]'-; the other is a migration of Mn" to a lattice site where it exists in a high-spin d5 state.',' The role of Mn in the photosynthetic liberation of 0 from H,O has occasioned a study of the polarographic reduction of Mn"'-porphyrinato-complexes in the presence of various anions.12* The order of the Mn"'-+ Mn" potentials ( - E + ; most stable Mn"' species first) is F- > OCN- 3 N,- 2 OAc- > OH- 3 C1- > SCN- 2 Br- > I-.The state of aggregation of Mn(acac), J . Kloubek and J. Podlaha Inorg. Nuclear Chem. Letters 1971 7 67. Manojlovic-Muir J . Chem. SOC. ( A ) 1971 2796. A. J. Edwards J . Chem. SOC. ( A ) 1971 2653 3074. I. Bernal N. Elliott and R. Lalancette Chem. Comm. 1971 803. '*' J. Chatt L. Manojlovic-Muir and K. W. Muir Chem. Comm. 1971 655; L. l Z 5 C . Bellitto A. A. G . Tomlinson and C. Furlani J . Chem. SOC. ( A ) 1971 3267. ''' 1 2 6 M . R" uegg A. Ludi and K. Rieder Znorg. Chem. 1971 10 1773. M. B. D. Bloom J. B. Raynor K. D. J. Root and M. C. R. Symons J . Chem. SOC. ( A ) , 1971 3212. L. J. Boucher and H. K. Garber Inorg. Chem. 1970,9 2644 384 R. J. Cross and J.M . WinJield in various non-aqueous solvents has been examined by e.s.r. spectroscopy. The compound is monomeric in dimethylformamide dimeric in a diethyl ether-pentane-alcohol mixture and has a linear trimeric structure in o-terphenyl. 129 X-Ray work has shown that Ba,MnX (X = S or Se) are isostructural with K,AgI, with corner-sharing MnX tetrahedra forming an infinite chain struc-ture. The compounds behave as linear-chain antiferromagnets. ' 30 Technetium and Rhenium.-There have been interesting developments in the synthetic chemistry of Re notably an improved route to ReC1 ,13' the preparation of ReOC1,,132 and the isolation of a ReC1,- The reaction of C1 with pure Re metal leads to a product which is a mixture of ReCI and impure ReOCl ,13 but reactions occurring below room temperature between ReF, and BCI or CCl give pure ReCI .I 3 ' The compound is a green-black solid, m.p. 302 K which on heating gives ReCI and C1,. A similar reaction between ReF and BBr leads to ReBr,. ReF is comparable in its reactivity to MoF,, and for example undergoes a redox reaction with PF to give PF and ReF,. Surprisingly the behaviour of ReF and ReF is very similar although the reactions of the latter are more In other work on Re fluorides it has been shown that ReF and ReOF, whose gas-phase vibrational spectra, along with that of OsOF, have been assigned in C, symmetry form adducts with FNO and FNO,. Ionic structures AfReF,- and A+ReOF,- (A = NO or NO,) are suggested with D, and C, symmetries respectively for the anions. ' 3 s Although many complexes of ReOCl are known previous attempts to isolate the compound have been unsuccessful.It has now been prepared by three routes the best of which is the photoreduction of ReOCl using 350 nm radiation. It is dimorphic a purple o! form changing to a purple-grey p modification with time in uucuo. Both forms appear to contain Re=O groups and have structures which are different from that of monoclinic MoOCl,. ReOCI decomposes on heating and in CCl or TiCl solution to give Re,CI, ReOCl, and Re0,C1.'32 A compound formulated as [PCI,'] [ReCI,-] has been reported', from the reaction of ReCI and PCI at 573 K. The ReC1,- anion is apparently stabilized by PCl,' as ReC1,,- salts are formed when [PCI,] [ReCl,] reacts with alkali-metal halides. R,N+ ReC1 - is formed from ReCI and R,NCl (1 1 molar ratio) in CH,Cl solution under anaerobic conditions.136 A polymeric structure with octahedral Re and cis- bent chloro-bridges is suggested for ReCI - from its A. Hudson and M. J. de G. Kennedy Inorg. Nuclear Chem. Letters 1971 7 333. ( a ) J. H. Canterford and A. B. Waugh Znorg. Nuclear Chem. Letters 1971 7 395; ( b ) J. H. Canterford T. A. O'Donnell and A. B. Waugh Austral. J . Chem. 1971 24, 243. P. W. Frais C. J. L. Lock and A. Guest Chem. Comm. 1971 75. P. W. Frais C. J. L. Lock and A Guest Chem. Comm. 1970 1612. J. H. Holloway H. Selig and H. H. Claassen J . Chem. Phys. 1971 54 4305; H. Selig and Z . Karpas Israel. J . Chem. 1971 9 53. 130 I. E. Grey and H. Steinfink Inorg. Chem. 1971 10 691. 1 3 1 1 3 ' 1 3 3 1 3 4 A.Guest and C. J. L. Lock Canad. J . Chem. 1971,49 603. 1 3 6 D. G. Tisley and R. A. Walton J . Chem. SOC. ( A ) 1971 3409 The Transition Elements 385 spectra. ReCl is also easily reduced by C2C14 to give ReCl, and this represents a convenient preparation of the tetrachloride. ' 37 Complexes of Re with nitrogen ligands continue to be widely studied. One example of work in this field describes the preparation of rhenium aroylhydrazido-complexes (2) from the reactions of ReOCI,(PPh,) with mono- or di-aroyl-hydrazines. 13' Reaction of these compounds with nucleophilic reagents (L = MeCN py or PR,) leads to ring opening with the formation of arylazo-com-plexes [Cl,(PPh,),ReL(N,CO.Ar)]. When L = PR the diamagnetic complexes have a meu-configuration. Ph,P N-N c1\ 1 /I \\ Cl'I 0 Re ,C-Ar 8 The Iron Group Iron.-The eight-co-ordinate iron(rI1) complex [Ph,As] [ Fe(NO,),] has been examined by X-ray crystallography,' 3 9 and a dodecahedra1 (D2d) structure has been assigned to it.The geometry is similar to that of the eight-co-ordinate species [Mn(N0,),I2- and [Fe(naphthyridine),12+ reported last year. A comparison of the Mossbauer and visible-u.v. spectra of Fe"' complexes of edta and Hedta in solution and as solids indicates that the compounds are seven-co-ordinate in H,O MeOH formamide or glycerol but six-co-ordinate in DMSO or DMF.14' It seems likely that edta and Hedta act as quinquedentate ligands allowing one or two solvent molecules to co-ordinate. The crystal structure of the fluoroboro-tris-(2-carboxaldimino-6-pyridyl)phosphinenickel(11) ion was reported last year and showed that the nickel atom was co-ordinated to six nitrogen atoms in a trigonal-prismatic arrangement.While the Zn" and Cot' analogues are isomorphous with the nickel derivative [Fe"(FB(ONCH.C,-H3N)3P)]+ is not and its crystal structure has now been publi~hed.'~' The N6 cage around the Fe atom is twisted 21" from a trigonal-prismatic arrangement, and the geometry of the ligand suggests that it is considerably strained by this twist. The observed configuration probably represents a balance between the trigonal-prismatic structure preferred by the ligand and the octahedral geometry preferred for strong-field d6 Fe" because of ligand-field stabilization energy. Far-i.r. techniques (3-100 cm- ') have been used to investigate directly the effects of large ligand fields on paramagnetic ions in molecules.'42 The magnetic resonances of Fe"' in sites with large axial and rhombic ligand-fields have been measured between 1.3 and 50K in applied magnetic fields of flux density 5.0 13' A.Brignole and F. A. Cotton Chem. Comm. 1971 706. 1 3 ' J. Chatt J. R. Dilworth G. J. Leigh and V. D. Gupta J . Chem. SOC. ( A ) 1971 2631 1 3 9 T. J. King N. Logan A. Morris and S. C. Wallwork Chem. Comm. 1971 554. I4O K. Garbett G. Lang and R. J. P. Williams J . Chem. SOC. ( A ) 1971 3433. 14' 14' G. C. Brackett P. L. Richards and W. S. Caughey J . Chem. Phys. 1971,54 4383. M. R. Churchill and A. H. Reis jun. Chem. Comm. 1971 1307 386 R. J . Cross and J . M . Winjield Tesla.The transmission spectra of polycrystalline samples of iron(Ir1) porphyrins and dithiocarbamates myoglobin haemoglobin and ferrichrome have been examined. The spectra are consistent with spin-Hamiltonian formulation and the spin-Hamiltonian parameters can be obtained directly from the spectra. The energy separation between 5G and ' A at the ground-state cross-over in [Fe"N,] complexes is found to be strongly temperature dependent.14 This is consistent with a simultaneously occurring change in the Fe-N bond-lengths, and such a change found in one compound was reported last year. On this basis similar results are forecast for related d4 d 5 d6 and d7 complexes. This year changes in Fe-S bond lengths with spin state are reported though not for the same compound.144 The crystal structures of high-spin tris-(N-methyl-N-phenyldithiocarbamato)iron(m) have been calculated and a contraction of 10 pm on going from high to low spin is apparent. The high-spin form approximates to D rather than Oh symmetry and the low-spin form approaches C,. The latter is most probably due to the '?& state being susceptible to Jahn-Teller and spin-orbit interactions. The crystal structure of [(Et,NCS,),Fe{ S,C,(CF,),)] repre-sents the first crystallographic investigation of an iron(rrr) complex with high-spin and low-spin states in about equal population^'^^ (at 290 K). Interestingly, no anomalous bond lengths were observed and the thermal ellipsoids for the sulphur atoms were nearly normal. y-Irradiation of Fe(acac) for ca. one hour greatly reduces the Mossbauer spectrum 1 i n e ~ i d t h .l ~ ~ Other iron(m) derivatives behave in a similar way and the effect may be quite general. A postulated explanation is the possible formation of Fe(acac) -. Electron movement from molecule to molecule could then provide a rapid relaxation process. The Mossbauer spectra of bis-(NN-diethyldithio-carbamato)iron(m) chloride and thiocyanate and of the Bu",N+ salts of bis-(maleonitriledithiolato)iron(m) and bis(toluenedithiolato)iron(uI) have been I s, (3) Et 1 4 3 E. Konig and S . Kremer Chem. Phys. Letters 1971 8 312. 144 P. C. Healey and A. H. White Chem. Comm. 1971 1446. 1 4 5 D. L. Johnston W. L. Rohrbaugh and W. de W. Horrocks,jun. Znorg. Chem. 1971, 10 1474. 1 4 6 G. M. Bancroft K. G. Dharmawardena and A.J. Stone Chem. Comm. 1971 6 The Transition Elements 387 recorded for pure solids and in solvents.'47 The large quadrupole splitting in the crystals is greatly reduced on solvation and this is most probably due to the change in co-ordination number at iron from 5 to 6. The X-ray crystal structure of bis(ethy1thioxanthato)-pbis(ethy1thioxan-thato)-p-bis(ethy1thio)di-iron(m) (3) shows an Fe-Fe distance of 261.8 pm, which is shorter than the bite of the bridge thioxanthates. This along with the Fe-S -Fe angle of 72.35" for the bridging ethylthio-groups strongly suggests the presence of iron-iron bonding.'48 The e.s.r. and vibrational spectra of FeL,-(ClO,) and FeL,X3 (L = Ph3P0 or Ph3AsO; X = C1 Br NO, or NCS) show the presence of square-planar [L4FeI3+ units for the perchlorates and of trans-octahedral [FeX,L,]+ along with [FeX,] - anions for the chlorides and bro-m i d e ~ .' ~ ~ The others are monomeric and five-co-ordinate. The occurrence or absence of cation ordering and the extent of magnetic ordering in complex phases derived from the rutile structure in FeF have been studied by Mossbauer spectroscopy over a wide range of temperature^.'^' The ironjir) compounds FeCoNiF, Mg,FeF, and MgFe2F are disordered rutile phases with Nee1 temperatures corresponding to the weighted averages of the component metal fluorides. The complex LiFe,F shows separate spectra from Fe2 + and Fe3 + in both the paramagnetic and magnetically ordered regions, demonstrating the absence of 'electron hopping'. Small linewidths indicate complete geometric ordering and the repeating cation sequence in the c direction is Lif(Fe2+ T )(Fe3' L )Li+(Fe2+ 1 )(Fe3' ? ) leading to overall antiferro-magnetic behaviour.The trirutile compound LiMgFeF, on the other hand, showed a range of quadrupole splittings consistent with the ordering of Fe3+ into every third layer along the c direction with random Li' and Mg2+ in the intervening layers. The ferrate(v1) compound K,FeO has been shown to act as a selective oxi-dizing agent. ' ' Primary and secondary alcohols are rapidly oxidized to alde-hydes and ketones respectively at room temperature whereas double and triple bonds aldehydes tertiary alcohols and amines are not affected. Good yields and no by-products are formed in aqueous basic media. Doubt has been cast on the reversibility of the pressure-induced conversions of Fe3 + to Fe2 ' (see 1969 Report).Infrared-spectroscopic examinations of solid cyanoferrates(II1) under pressure revealed only an irreversible reduction of a type already known,'52 and no evidence for the previously reported process which had been followed by Mossbauer spectroscopy. No reductions took place in solution. The overlapping absorptions in the 57Fe Mossbauer spectra of Prussian Blue and Turnbull's Blue have been greatly simplified by selectively labelling the iron atoms using Mossbauer-active and then -inactive isotopes.'53 The 14' J. L. K. F. de Vries J. M. Trooster and E. de Boer Inorg. Chem. 1971 10 81. 1 4 8 D. Coucouvanis S. J. Lippard and J. A. Zubieta Inorg. Chem. 1970 9 2775. 1 4 9 S.A. Cotton and J. F. Gibson J . Chem. SOC. ( A ) 1971 859. l S N. N. Greenwood A. T. Howe and F. Menil J . Chem. SOC. ( A ) 1971 221 8. l S 1 R. J. Audette J. W. Quail and P. J. Smith Tetrahedron Letters 1971 279. 1 5 2 R. G. Gardiner S . D. Hamann and M. Linton Austral. J . Chem. 1970 23 2369. l S 3 A. K. Bonnette jun. and J. F. Allen Inorg. Chem. 1971 10 1613 388 R . J. Cross and J . M. Winjield results show the two Blues to be identical. The method might be applied whenever suitable labelling techniques are available. Vacuum pyrolysis of Prussian Blue [iron(II) hexacyanoferrate(~~r)] is reportedls4 to convert it to iron(1Ir) hexa-cyanoferrate(1r). "Fe has been introduced into soluble Prussian Blue to produce KFe[58Fe(CN),],H,0 and into potassium hexacyanoferrate(r1) to give K4[58Fe(CN),],3H20.The transition "Fe(n y)59Fe was then accomplished by neutron irradiation and the amounts of 59Fe retained in the complexes were determined.lS5 This was only 5 % for the Prussian Blue compared with ca. 25 % for the simple complex. This is due to initial expulsion of the 59Fe from the complex by recoil. The unlabelled iron in the Blue then competes for the site. The oxidation of sulphite by hexacyanoferrate(rr1) has been shownlS6 to pro-ceed oia the ions [Fe(CN)s(CNS0,)]5- and [Fe(CN),(CNS0,)I4-. This latter species hydrolyses to hexacyanoferrate(I1) and S042-. The hexacyanoferrate(I1r) oxidation of the selenium(rv) species HSeO, - catalysed by Os""' follows the ~equence'~' shown in Scheme 1. HSe043- + Fe(CN),3- + HSe0,'- + Fe(CN),4-HSe0,'- + Osvil' -+ HSe0,- + [reduced Os] [reduced Os] f F I ~ ( C N ) ~ - + 0s""' + F I ~ ( C N ) ~ -Scheme 1 Further consideration of the properties of the nitroprusside ion supports its formulation as an Fe3 +- complex with NO acting as a neutral ligand.' 58 Ruthenium and Osmium.-This past year has seen an increase in the application of Mossbauer spectroscopy to ruthenium chemistry. The 90 keV transition of 99Ru has been observed. The series of Ru" species [Ru(CN),L]"- (L = NO+, CN- or and [RuL,(NO)] (L = CN- NH, NCS- C1- or Br-)I6' have been examined and the results are generally similar to those for analogous iron compounds. The isomer shift decreases as the ligand-field strength of L decreases (the order in which the ligands are listed above) and the quadrupole splittings can be interpreted in terms of the o-donor-n-acceptor abilities of the ligands.An examination of anhydrous ruthenium(II1) halides16' suggests that isomer shift and quadrupole splitting decrease with decreasing ligand electro-negativity. This is rationalized in terms of increased 4d occupation via overlap of populated ligand n-orbitals and partially populated t l g metal orbitals. 'Ruthenium red' and 'ruthenium brown' are materials commonly encountered in ammine chemistry of Ru. A Mossbauer study has at last characterized the D. S. Murty J. G. Cosgrove and R. L. Collins Nature 1971 231 311. l s 5 J. Fengor A. G. Maddock and K. E. Siekierska J . Chem. SOC. ( A ) 1970,3255. 1 5 6 J. M. Lancaster and R. S. Murray J . Chem. SOC. ( A ) 1971 2755.Is' V. K. Jindal M. C. Agrawal and S. P. Mushran J . Chem. SOC. ( A ) 1971 622. l S 8 D. B. Brown Znorg. Chim. Acta 1971 5 314. l S 9 C. A. Clausen tert. R. A. Prados and M. L. Good J . Amer. Chem. Sac. 1970 92, 160 R. Greatrex N. N. Greenwood and P. Kaspi J . Chem. SOC. ( A ) 1971 1873. 1 6 ' 7482. C. A. Clausen tert. R. A. Prados and M. L. Good Chem. Phys. Letters 1971 8, 565 The Transition Elements 389 complexes,'62 both of which contain both Ru"' and Ru". Ruthenium red is depicted as [(NH,),Ru'1'-O-Ru'V(NH3)4-O-R~'''(NH3)5]6~ whilst the brown is [(NH ,) Ru'" - 0 - Ru"'(NH,) -0 -RuIV(NH ,) ,] + . The Mossbauer spectrum of SrRu0 at 4.2 K and 77 K shows hyperfine splitting'63 compatible with the ferromagnetic moment derived from neutron-diffraction studies.The crystal structure of [Ru(N,)(N,)(en),]PF shows the Ru-N distance to be 189.4(9)pm shorter than the Ru-N bond length of 212.1(8)pm.164 This suggests some multiple-bond character in the bonding of dinitrogen to ruthenium. The role of nitrous oxide complexes as intermediates in some preparative routes to dinitrogen compounds has been mentioned in previous years' Reports. This year the conversion of [(NH,),Ru"NO]~+ to [(NH3),-Ru"N,O]~+ by the reagents NH,OH N2H, or NH is re~0rted.l~' The latter two reagents also produce some [Ru(NH,),N,],+. A dinuclear N,O complex is also reported,166 probably with bridging N,O. The reaction products from the reduction of [RU(NH,),CI]~+ in aqueous acid solution by Zn-Hg or H2 on Pt absorb N 2 0 at atmospheric pressure.The complex [(Ru(NH,),),N,O]-(BF,) can be isolated. The dark green compounds derived from RuC1 hydrates in acetic acid and believed'67 to be Ru,(p-OAc),L (L = py Ph,P or solvent) have now been formulated as trimeric Ru,O species with triply bridging oxygen. ''* The species [Ru,O(OAC),(H,O),] + analogous to well-known Cr Mn and Fe compounds, is present in acidic solution. A similar anionic complex is found in alkaline solu-tions. The complex can be reversibly reduced to a light-green compound which reacts with Ph,P to produce [Ru,O(OAc),(PPh,),] (Scheme 2). X-Ray studies on this compound show a triangle of ruthenium atoms about 0 [Ru-0 = 192(2)pm] with acetate ions bridging Ru pairs. This Ph,P derivative can be formed by the action of triphenylphosphine without prior reduction and in this case Ph3P0 is given as a by-product.OH ~ [RU~O(OAC),(OHZ)OHI [Ru30(0Ac)6(0H,)(0H),1-Ph,P OHfH + [ u3 O(OAc)6( Z O) 3 1 + -\ Scheme 2 1 6 2 1 6 3 1 6 4 1 6 5 1 6 6 1 6 7 1 6 8 C. A. Clausen tert. R. A. Prados and M. L. Good Inorg. Nuclear Chem. Letters, 1971 7 485. T. C. Gibb R. Greatrex N. N. Greenwood and P. Kaspi Chem. Comm. 1971 319. B . R. Davies and J. A. Ibers Inorg. Chem. 1970 9 2768. F. Bottomley and J . R. Crawford Chem. Comm. 1971 200. J. N. Armor and H. Taube Chem. Comm. 1971,287. P. L. Legzdins R. W. Mitchell G. L. Rempel J. D. Ruddick and G. Wilkinson, J. Chem. SOC. ( A ) 1970 3322. F. A. Cotton J. G. Norman A. Spencer and G. Wilkinson Chem. Comm. 1971, 967 390 R . J . Cross and J . M .Winfield 9 The Cobalt Group Cobalt.-An examination of the electronic absorption spectra of [(bipy),Co'] + and related complexes has led to the assignment of a band in the near-i.r.-visible region as a metal ligand charge-transfer band.'69 It was identified from the effects of methyl substituents on the bipy rings small displacements of the absorption at 7200 cm- being observed. Redox isomerism between Co"'-NO-and Co'-NOf has been detected by i.r. spectroscopy. 170 The presence of both co-ordinated NO+ and NO- was shown last year from the crystal structure171 of [(Ph3P),Ru(NO),C1]PF6. Labelling one of these nitrosyls by 5N demonstrated that exchange between the two was rapid.'70 Similar multiplicity of v(N0) in labelling experiments on [L,CoCl,(NO)] [L = Et,P Bu",P Ph,MeP Ph,P, or (p-tol),P] suggests the presence of a similar tautomerism this time involving trigonal-bipyramidal cobalt(1) or square-pyramidal cobalt(II1) : 0 Jahn-Teller distortion is detected in the crystal structure' 7 2 of K,Ba[Co-(No,),] at 233 K.An elongation along one axis as commonly found at Cu", is observed. At room temperature however a dynamic Jahn-Teller effect operates to remove the asymmetry. Magnetic moment determinations on (Bu",N) [Co(biX),] (biX = toluene-3,4-dithiolato) at 4.2 K indicate a singlet gr~und-state,'~~ and not a triplet state as reported previously. The complex is still unique however in that it has a triplet excited state which is very low-lying. The photochemical decomposition of the psuperoxo-dicobalt ammines [(NH3)5Co-(p-0,)-Co(NH3)5]5+ and [(NH3)4Co-(p-02)(p-NH,)-Co(NH3)4]4+ in aqueous acidic media has been examined.174 Irradiation at near-u.v. frequen-cies gives efficient production of [(NH3)5Co(H,0)]3+ Co2+ and 0 in 1 1 1 ratios. This decomposition follows population of a ligand * cobalt charge-transfer excited state. No excited-state O, spin-paired Co" or free radicals were detected. The complexes trans-[Co(quadriL)(NO,)CI]NO and trans-[Co(quadriL)-(CN)Cl]NO have been characterized and their acid aquation compared to that of trans-[Co(quadriL)(OH)CI]NO (quadriL = 1,4,8,1 l-tetra-azacyclotetrade-cane). Aquation causes displacement of C1- and proceeds by a dissociative l b 9 Y . Kaizu Y . Torii and H. Kobayashi Bull. Chem. SOC. Japan 1970 43 3296. J. P. Collman P. Farnham and G .Dolcetti J . Amer. Chem. SOC. 1971,93 1788. C. G . Pierpoint D. G . Van Derveer W. Durland and R. Eisenberg J . Amer. Chem. Suc. 1970 92 4760. J. A. Bertrand D. A. Carpenter and A. R. Kalyanaraman Znorg. Chim. Acta 1971, 5 113. C. R. Ollis D. Y. Jeter and W. E. Hatfield J . Amer. Chem. Soc. 1971 93 547. 1 7 3 1 7 4 J. S. Valentine and D. Valentine jun. J . Amer. Chem. SOC. 1971 93 1 1 11 The Transition Elements 39 1 mechanism with retention of configuration. 17' The aquation of the hydroxy-complex is more facile than can be explained by the electronic properties of the ligands however and the formation of an internal amide conjugated base as a reaction intermediate is postulated as shown in Scheme 3. H \ / H 0 . H .,y - 0. 0 H H' H H H \ + 0-H H .. . O l '. / H' 0 Cl Scheme 3 The anion S 2 0 g 2 - is known to reduce Co"' ammines to Co2+. Further experi-m e n t ~ ~ ~ ~ confirm the stoicheiometry [CO(NH,),(OH,)]~ + + S 2 0 g 2 - + H + + Co2+ + iN + 4NH4+ + H,O + 2S042- under reaction conditions which do not produce CO,. The same ratio of Co"' S20g2- N (2 2 1) is also found when [CO(NH,),(OH,),]~ + replaces the penta-ammine. Some N,O is also usually formed in both reactions. When the complex ion [Co(NH,),-(OH,),] + is used as the reacting substrate the only gaseous product is 0 and would decompose in thf absence of Co"' so the reactions probably proceed via S 2 0 B 2 - + SO,- %Co'" + S042-. This can lead to co-ordinated nitrene (NH) which produces N by an intermolecular process. The XO bond formation of N 2 0 is an intermolecular process and co-ordinated NW20H is suggested as an intermediate.The photolysis of [CO(NH,),OAC]~+ in aqueous solution at 254 nm pro-duces Co2+ CO, C,H6 and CH, and the quantum yields @Co2+ % @CO % (2@C,H6 + QCH,) areca. 0.19. Electron transfer from OAc to Co"' is responsible for the decomposition which proceeds oia CH,. radical produc-t i ~ n . ' ~ ~ Both 1 7 0 and 14N n.m.r. spectroscopy have been used to follow the substitution of water by NCS- at coba1t(111)."~ The species present are [ C O ( H ~ O ) ~ I ~ + [Co(NCS)(H20)5]+ [Co(NCS),(H20)2] [CO(NCS),(H~O)I-, and [Co(NCS),]'-. This is in agreement with other systems where the switch from six- to four-co-ordination occurs at the neutral species. Aspects of the chemistry of cobalt(I1r) in aqueous perchloric acid have been reviewed,' 7 9 as has the stereochemistry of five-co-ordinate complexes of Co" and Ni".c0"I . . S20g2- O2 is 2 2 3. The amount of S2082- consumed is the same as 17' K. Mok and C . K. Poon Inorg. Chem. 1971 10 225. 1 7 6 J. D. White and H. Taube J . Phys. Chem. 1970 74 4142. 1 7 7 1 7 ' A. H. Zeltmann and L. 0. Morgan Inorg. Chem. 1970 9 2522. 1 7 9 G. Davies and B . Warnqvist Co-ordination Chem. Rev. 1970 5 349. E. R. Kantrowitz M. Z. Hoffman and J. F . Endicott J . Phys. Chem. 1971,75 1914. P. L. Orioli Co-ordination Chem. Rev. 1971 6 285 392 R . J . Cross and J . M . Winjield Rhodium and Iridium.-The crystal structure of (Ph,P),Rh2(dmg) (dmg = dimethylglyoximato) has been determined and a Rh-Rh bond distance of 293-6 pm revealed.181 The covalent radius of Rh"' is set at 139 pm from an X-ray investigation of (Ph3P)Rh(dmg)2C1,182 and on this basis the Rh-Rh link in the former compound may be assigned as a single bond.The rhodium-rhodium bond in Rh,(OAc),(H,O), reported last year as 238.6pm must then be a multiple bond. The crystal structureL8 of Rh,(OAc),(dmg),(Ph,P) shows the Rh-Rh bond to be intermediate to the others with a length of 261.8 pm. The situation here is complicated by the fact that while the acetate groups bridge the rhodium atoms the dimethylglyoximato-groups do not and are rotated 20" away from the eclipsed position. The terminal Ph,P ligands are almost colinear with the Rh-Rh bond. Dinuclear species with metal-metal bonds are thought to be present from the electrochemical reduction of [Rh"'(en),Cl,] + in water.ls4 The water molecules of the product [(H20)(en)2Rh-Rh(en),(H20)]4+ are easily replaced by C1- Br- or I- and all the compounds are easily re-oxidized.Irradiation of the metal-ion absorption bands of [Rh(NH,),II2+ in aqueous solution produces tr~ns-[Rh(NH,),(H,O)1]~~ with 90 % efficiency.Is5 An almost square-pyramidal geometry is suggested for the intermediate Rh(NH,),I species. The oxidation of tetraphenylborate(u1) by hexachloroiridate(1v) has the stoicheiometry 186 BPh4- + 2IrCl,,- + H 2 0 + BPhzOH + Ph + 2IrCl,,- + H+ Yields in aqueous solution are quantitative and the mechanism involves forma-tion of BPh4* radicals. Trimeric iridium compounds with triply bridging 0 or N were reported last year and the crystal structure of [Ir3N(S04)6(H20)3]I(4 has now been e~amined.'~' The coplanar Ir,N unit is symmetrical with Ir-N = 19143 pm.The 1931r Mossbauer spectrum of this compound had suggested that the iridium atoms were not equivalent owing to differing oxidation numbers. It is still possible that this is the case with a chance equal distribution influencing the X-ray work. Co-ordinated nitrenes are featured in an increasing number of reaction se-quences. The electrophilic nature and synthetic possibilities of these nitrenes are illustrated by the reaction of [Ir(NH,),NHI3+ prepared from [II-(NH,),N,]~+, depicted in Scheme 4.'88. I n ' l S 2 F. A. Cotton and J. G. Norman,jun. J. Amer. Chem. SOC. 1971,93 80. K. G. Caulton and F.A. Cotton J. Amer. Chem. SOC. 1971 93 1914. J. Halpern E. Kimura J. Molin-Case and C. S. Wong Chem. Comm. 1971 1207. R. D. Gillard B. T. Heaton and D. H. Vaughan J. Chem. SOC. ( A ) 1971 734. T. L. Kelly and J. F. Endicott Chem. Comm. 1971 1061. P. Abley and J. Halpern Chem. Comm. 1971 1238. M. Ciechanowicz N . P. Griffith D. Pawson A. C. Skapski and M. J. Cleare Chem. Comm. 1971 876. B. C. Lane J. W. McDonald V. G. Myers F. Basolo and R. G. Pearson J. Amer. Chem. SOC. 1971,93 4934 The Transition Elements 393 [II-(NH~)~N~]" H' [Ir(NH,),NHI3 ' + N, [I r( NH 3)5 NH OSO,] + P [Ir(NH,),NH,C1]3 ' 1H.O [ Ir( NH 3)5 NH OH] + Scheme 4 10 The Nickel Group Nickel.-The reaction of a quadridentate macrocycle complex of nickel(1) with molecular oxygen is complicated and although their characterization is not yet complete some unusual products are i n d i ~ a t e d .' ~ ~ The absorption of 0, by methyl cyanide solutions of [Ni(quadriL)]BF (quadriL = 1,4,8,11 -tetra-aza-5,5,7,12,12,14-hexamethyltetradecine) is accompanied by a colour change from green to blue and all the starting material is consumed by one third of an equivalent of 02. The products include [Ni(quadriL)O,]BF, which is para-magnetic and may well be a cyclic peroxide and material containing co-ordinated MeCN and a new macrocyclic ring modified at one co-ordination site at least and possibly more {neither [Ni(quadriL)]BF nor [Ni(quadriL)] (BF4) will co-ordinate MeCN). The data suggest that 0 co-ordinates to a molecule of the Ni' complex which then attacks two other molecules.When an excess of 0 is present a brown material is formed but treatment of this with CN- liberates 42 of quadril supporting the proposition that the 0 complex contains the unaltered ligand. Atomic nickel reacts with molecular nitrogen at low temperatures to produce the first complexes containing only dinitrogen as ligands.' 90 Condensation of nickel atoms into a nitrogen or nitrogen-argon matrix at 17-26 K produces Ni(N2)x where x is 1 or 2. ''N labelling confirms the assignment of bands near 2170cm-' to v(NN). Similar complexes of chromium have been prepared in analogous reactions. The complexes decompose when the matrix is boiled off at ca. 42 K. The isomerism of L,NiX (L = tertiary phosphine; X = halogen) between tetrahedral and square-planar geometry has attracted a great deal of attention in recent years.Metal-isotope enrichment studies have now assigned v(Ni-P) and v(Ni-Br) in both isomer^.'^' These vibrations in [(Ph,RP),NiBr,] (R = alkyl) fall at ca. 260 cm- ' and ca. 330 cm- ' respectively for the planar complexes, and at ca. 180cm-' and ca. 250cm-' respectively when the geometry is J . Vasilevskis D. C. Olson and K. Loos Chem. Comm. 1970 1718. l Y o J. K. Burdett and J. J. Turner Chem. Comm. 1971 885. l Y 1 J. T. Wang C. Udovich K. Nakomoto A. Quattrochi and J. R. Ferraro Inorg. Chem., 1970 9 2675 394 R. J . Cross and J . M . Winjield pseudotetrahedral. The halogen n.q.r. spectra of the tetrahedral (Ph,P),NiX, and of the trans-planar (Pr",P),NiX (X = C1 or Br) reveal a large difference in resonance frequency between the two g e ~ m e t r i e s .' ~ ~ This is interpreted in terms of halogen + metal n-bonding of ca. 10 % for the tetrahedral compounds. Magnetic moment measurements and i.r. and electronic spectra of the com-plexes L,NiX (L = 1-benzyl-2-phenylbenzimidazole; X = C1 Br I NO,, or SCN) indicate various geometric isomers.'93 The chloride is tetrahedral, and the bromide has both square-planar and tetrahedral isomers. The iodide and thiocyanate are found only as square-planar complexes but the nitrate exists in two octahedral modifications in the solid. The crystal structure of [Cr(biL),] [Ni(CN),],2H20 (biL = 1,3-propylenediamine) shows the anion to be square-pyramidal and v(CN) modes are assigned in both i.r. and Raman spectra. 194 On partial dehydration to [Cr(biL),] [Ni(CN),],l.SH,O the CN frequencies are consistent with the presence of both square-pyramidal and trigonal-bipyramidal [Ni(CN),I3-.Complete dehydration however leaves only absorptions typical of the square-pyramidal form. Interestingly this is the geometry found in aqueous solution. The crystal structure of cis,cis-1,3,5-tris(pyridine-2-aldimino)cyclohexanenickel(11) perchlorate has been reported. 1 9 5 The ligand is designed to constrain metals in trigonal-prismatic geometry. In this case the N cage is twisted 32" away from the eclipsed position. The mechan-ism of ligand replacement at octahedral Ni" has been reviewed.'96 The electronic spectra of low-spin square-pyramidal [Ni(diars),X]"+ (X = C1, Br I SCN thiourea or NO,) complexes have been recorded between 77 and 300 K and allow the assignment of ligand-field bands.I9' The d-orbital energy sequence x y < xz yz < z2 << x2 - y 2 is found.The order of dxy d, is the reverse of that expected from simple crystal-field considerations and an explanation might lie in n-bonding between Ni and As. The spectra are distinctly different from those of low-spin trigonal-bipyramidal complexes of nickel(I1) and provide a good means of assigning stereochemistry. The complex [Co,(p3-OMe),(acac),(MeOH),] has been shown by X-ray diffraction studies to contain a 'cubane'-type core of Co,(OMe) . The nickel(1r) analogue is isostructural (a similar structure was reported in 1969) each nickel atom having pseudo-octahedral geometry. 98 Magnetic 'susceptibility measure-ments from 1.63-296 K show intramolecular ferromagnetic coupling of the eight eg electrons and the S = 4 ground-state is fully populated at 21 K.This cluster compound is unique in that further weak intermolecular ferromagnetic coupling was also detected at low temperatures. 1 9 2 1 9 3 K. S. Bose and C. C. Patel J . Inorg. Nuclear Chem. 1971 33 755. 1 9 4 A. Terzis K. N. Raymond and T. G. Spiro Inorg. Chem. 1970 9 2415. 1 9 5 E. B. Fleisher A. E. Gebala and D. R. Swift Chem. Comm. 1971 1280. 1 9 6 R. G. Wilkins Accounts Chem. Res. 1970 3 408. 19' J. R. Preer and H. B. Gray J . Amer. Chem. SOC. 1970,92 7306. 1 9 * J. A. Bertrand A. P. Ginsberg R. I. Kaplan C. E. Kirkwood R. L. Martin and P. W. Smith and R. Stoessiger Chem. Comm. 1971 279.R. C . Sherwood Znorg. Chem. 1971 10 240 The Transition Elements 395 The thermal decomposition of nickel acetate has been found to nucleate on the surface and along lines of internal d i s l ~ c a t i o n . ' ~ ~ When the evolved gases are continuously removed the reaction-rate is reduced. The crystal structure of square-planar (4-methyliminopentane-2,3-dione-3-oximato)(4-iminopentane-2,3-dione-3-oximato)nickel(11) reveals an interesting difference in bonding between the two ligands.200" Where the former is joined to nickel by the oximato nitrogen atom the latter is attached by the oximino oxygen atom (4). Similar ligand isomerism is found is bis-(4-iminopentane-2,3-dione-3-oximato)nickel(11).~~~~ Last year a macrocyclic octadentate sulphide ligand holding two nickel atoms was reported.Chelating ligands with three2'' and four ,02 donor sites holding two nickel atoms by more conventional bridges, are depicted in (5) and (6). MeCOC- CMe I1 NMe 0 MeC\ 'I N I COMe A I1 c:; Ni < )Ni lo 1 N N \ r( Ni\ N O / T HN I U C 4 5 ) (4) 0 0 0 0 (6) I R2 I R' ( 7) Palladium and Platinum.-The synthesis and properties of several noble-metal oxides of the delafossite type (A'B'''0,) are reported. The compounds PtCoO , PdCoO, PdCrO, PdRhO, AgCoO, AgGaO, AgScO, AgInO, and AgTiO were made by high-pressure hydrothermal or metathetical reactions, 1 9 9 L. Tournayan H. Charcosset B. R. Wheeler J. M. McGinn and A. K. Galwey, J . Chem. Soc. ( A ) 1971 868. (a) M. J. Lacey C. G. MacDonald J. F.McConnell and J. S. Shannon Chem. Comm., 1971 1206; (b) M. J. Lacey C . G. MacDonald J. S. Shannon and P. J. Collins, Austral. J . Chem. 1970 23 2279. G. R. Brubaker J. C. Latta and D. C. Aquino Znorg. Chem. 1970,9,2608. W. J. Stratton and P. J. Ogren Znorg. Chem. 1970 9 2588. * 0 1 ' 0 396 R . J . Cross and J . M . WinjieId and single crystals of many were grown.203 The first four of the oxides listed contain monopositive Pd or Pt. The crystal structure of PtCoO reveals very short Pt -Pt distances and an anisotropic metallic conductivity is found when A is Pt or Pd. When A is Ag or Cu anisotropic semiconductivity is apparent, reflecting the longer M-M distances. Interest continues in compounds like Magnus' Green salt which crystallizes in a form containing chains of metal atoms.The anisotropic conductivity of this salt and the related complexes [Pf(NH3),] [PdCI,] and [Pd(NH,),] [PtCl,] have been compared and the conductivity of the mixed Pd-Pt compounds is ca. lo4 times less than that of [Pf(NH3),] [PtC14].204 The reduced metal-orbital overlaps in the mixed complexes are deemed responsible. [Pt(NH,Me),] [PtCI,] and [Pt(NH,Et),] [PtBr,] have been shown by X-ray crystallographic studies to be isostructural with Magnus'green salt.205 [Pt(NH,Et),] [PtCI,] has non-planar cations however and this prevents effective Pt-Pt overlap despite a similar stacking arrangement of the ions. The effects of pressure on the properties of Magnus' Green salt and the related stacked-metal complexes [Pt(en),] [PtCI,], [Pd(NH,),] [PdCl,] and [Ir(CO),(acac)] have been related to structural changes in the crystal lattice.206 Theoretical calculations on [Pt(NH3),] [PtCl,] confirm significant intermolecular interactions but indicate no formal Pt -Pt covalent bonding.207 The cond~ctivity~'~ and U.V.spectra2'* of [Ni(biX),] and [Pd(biX),] (biX = dimethylglyoximato) have been recorded. The spectra polarized along the z-axis are attributable to charge transfer between neighbouring metal atoms and 3dZ2 + 4p transitions (for Ni). The crystal structure of [Pd(NH,),NO,],-[Pd(NH,),] (NO,) precludes any Pd-Pd intera~tion.~'~ The structure has been used to interpret the polarized Raman single-crystal spectrum. Sulphide complexes of palladium and platinum have received attention this year. The ix. electronic and 'H n.m.r.spectra of square-planar trans-[L,MX,] (M = Pd or Pt; X = C1 or Br; L = Et,Se Bu",S Bui2S Bu',S or Prn,S) have been analysed and assignments made.,'' The selenide appears less effective as a n-acceptor ligand than sulphides or tertiary phosphines. The pyramidal con-figurations of the sulphur atoms in the complexes (7) (R1R2 = 2Et 2Ph or Et,Ph) make possible the presence of syn- and anti-isomers and these have been dis-tinguished by the 'H n.m.r. spectra of the compounds.21' Similar isomers are also present in the chelate complexes (RSC,H,SR)MX (M = Pd or Pt ; X = C1, Br or I ; R = Et Pr" or Bun) and inversion at sulphur causes interconversion '03 (a) R. D. Shannon D. B. Rogers and C. T. Prewitt Znorg. Chem. 1971 10 713; (b) R. D. Shannon D. B. Rogers C.T. Prewitt and J. L. Gillson Znorg. Chem. 1971, 10 723. '04 P. S . Gomm T. W. Thomas and A. E. Underhill J . Chem. SOC. (A) 1971,2154. ' 0 5 M. E. Cradwick D. Hall and R. K. Phillips Acta Cryst. 1971 B27 480. * 0 6 L. V. Interrante and F. P. Bundy Znorg. Chem. 1971 10 1169. '07 L. V. Interrante and R. P. Messmer Znorg. Chem. 1971 10 1174. ' 0 8 Y . Ohashi I. Hanazaki and S. Nagakura Znorg. Chem. 1970 9 251 1. ' O Y F. P. Boer V. B. Carter and J. W. Turley Znorg. Chem. 1971 10 651. ' l o B. E. Aires J. E. Fergusson D. T. Howarth and J. M. Miller J. Chem. SOC. (A) 1971, 2 1 1 1 144. H. A. 0. Hill and K. A. Simpson J . Chem. SOC. (A) 1970,3266 The Transition Elements 397 of the isomers. Variable-temperature n.m.r. spectrometry relates the rate of inversion at S to the trans-effect of X.,I2 Inversion is more rapid in the palladium complexes than in those of Pt.The kinetics of the reactions of 4,4'-disubstituted diphenyl sulphides with (p~)~PtC1 have been followed and they indicate that bond-making between Pt and the sulphide is the driving force.213 The results are in agreement with the inability of 4,4'-dinitrodiphenyl sulphide to co-ordinate to Pt". The kinetics of ring opening in (PhSC,H,SPh)PdX (X = C1 Br I SCN or N3) by amines in 1,Zdimethoxyethane are also r e p ~ r t e d . ~ l4 The crystal structure of di-iodo-bis(dimethyl-o-methyIthiophenylarsine)pa~ladium(~~) reveals it to be a square-planar trans-structure with short Pd-As links (the shortness due probably to n-bonding) but no bonding between sulphur and palladi~m.~' Palladium(I1) difluoride has been isolated from a mixture of Pd and PdF at 770-1000 K under a fluorine-argon The bright violet PdF2 reacts with MF (M = Ca Sr Cd Pb or Ba) at ca.1000 K to produce M[PdF,]. These complexes are red and contain square-planar PdF,,- ions. Liquid HF reacts with (Ph,P),Pto to produce [(Ph,P),PtF] (HF,).,17 Reaction of this complex with LiX produces [(Ph,P),PtF]X for X = BPh or BF, but with X = CIO the bridged dinuclear complex [(Ph3P)2Pt(p-F)2Pt(PPh3)2]X2 results. (Ph,P),PtFCl has been made from the action of liquid HF on (Ph,P),PtCI or (Ph,P),PtHCI. The reduction of [(NH3)5ClPt'V]3 -t by aqueous chromium(I1) proceeds by a (rate-determining) two-electron inner-sphere transfer 2 ' * PP-CI + Cr" -+ Pt" + Cr'V-Cl The Cr"C1 species rapidly reacts further with more Cr".An electrochemical redox process in a single crystal has been observed in K2Pt(CN),Br0. ,2.5H20. A d.c. potential gradient of 150 V cm-' or greater induces a reaction at the anode which spreads along the crystal to the cathode. l 9 The product is polycrystalline K2Pt(CN),,2H,O. Most probably Br- is discharged at the anode. Electrons can enter vacancies in the dZ2 band. 11 The Copper Group Copper.-The copper(I1) complexes of the cyclic tetra-amine ligands (8) and (9) have been converted electrochemically in acetonitrile to the Cu' and the Cu"' compounds.220 Similar reactions of nickel(I1) complexes of these ligands were 2 1 2 R. J. Cross G. J. Smith and R. Wardle Inorg. Nuclear Chem. Letters 1971 7 191. 'I3 J.R. Gaylor and C. V. Senoff Canad. J . Chem. 1971 49 2390. 2 1 4 L. Cattalini G . Marangoni J. S . Coe M. Vidali and M. Martelli J . Chem. SOC. ( A ) , 2 1 5 J . P. Beale and N. C. Stephenson Acta Cryst. 1970 B26 1655. * l 6 B. Muller and R. Hoppe Naturwiss 1971 58 262. R. D. W. Kemmitt R. D. Peacock and J. Stocks J. Chem. SOC. ( A ) 1971,846. ' I 8 J . K. Beattie and F. Basolo Inorg. Chem. 1971 10 486. * ' P. S . Gomm and A. E. Underhill Chem. Comm. 1971 51 1. 2 2 0 D. C. Olson and J. Vasilevskis Inorg. Chem. 1971 10 463. 1971 593 398 R . J . Cross and J . M . Winjield reported two years ago. The copper(m) compounds [Cu(quadriL)(MeCN)]X, (X = BF or CIO,) have been isolated as solids. They are stable below 258K, though the explosive nature of the perchlorates is emphasized.Pulse radiolysis (8) (9) studies221 lead to the conclusion that Cu"' exists in neutral solutions as C ~ ( o H ) ~ + ( a q ) or Cu(OH),+(aq) and that it decomposes via ~ C U ( O H ) ~ + - 2Cu2+ + H202. In acidic solution free radicals are formed by Cu3+(aq) OH' + Cu2+. The reaction between Cu+ and CU(OH)~+ is diffusion-controlled. More crystal structures of copper([) compounds and of mixed copper(I1)-copper(1) derivatives have been reported. In crystals of bis-(N-benzoylhydra-zino)copper(II) pentachlorotricuprate(1) the chelating ligands bond equatorially to Cu" and two distant chlorine atoms complete a distorted octahedron.222 All five C1 atoms are involved in bonding to the three copper(1) atoms in an infinite cylinder of distorted tetrahedra.The four pyridine molecules of [(py),Cu]ClO, adopt positions to give an almost perfect Cu'N tetrahedr~n,'~ the first to be confirmed by X-ray studies. The perchlorate ions are disordered in the lattice. Very distorted tetrahedral co-ordination is found in di-piodobis-[(o-dimethyl-aminopheny1)dimethylarsine-As,N]dicopper(~). The bond angle at the bridge iodides is 63.9" and the copper-copper separation of 272.7 pm does not preclude interaction.224 Co-ordination to copper([) in [(Me,PS),Cu]ClO is trigonal planar225 with the angle PSCu ca. 107". Linear Cu'C1,- is found in chloro(dodeca(dimethy1-amino)cyclohexaphosphazene-NNNN)copper(ti) dichlorocuprate(I).226 The bonding to Cu" is square-pyramidal with four N atoms from the ring and an apical chlorine. The 63Cu and 65Cu n.m.r.spectra of Cu' cyanides in aqueous solution have been examined and the presence of other ligands was found to affect the line width^.^^' This allowed estimations to be made of the formation constants K = [Cu(CN),-L(2+n)- ] [CN-]/[CU(CN),~-] [L"-] and these decrease in the order L = (NHJ2CS > SCN- > I - 2 NH > Br- 2 C1- 2 (NH,),CO. 2 2 1 2 2 2 R. J. Baker S. C. Nyburg and J. T. Szymanski Znorg. Chem. 1971 10 138. 2 2 3 A. H. Lewin R. J. Michl P. Ganis U. Lepore and G. Avitabile Chem. Cumm. 1971, 2 2 4 R. Graziani G. Bombieri and E. Forsellini J. Chem. Sac. ( A ) 1971 2331. 2 2 5 2 * 6 W. C. Marsh and J. Trotter J.'Chem. SOC. ( A ) 1971 1482. 2 2 7 T. Yamamoto H. Haraguchi and S. Fujiwara J . Phys. Chem. 1970 74 4369. D. Meyerstein Znorg.Chem. 1971 10 638. 1400. P. G. Eller and P. W. R. Corfield Chem. Comm. 1971 105 The Transition Elements 399 The activity of copper-based enzymes is believed to depend on Cu"-Cu' reversible redox systems in tetrahedral environments. The heteropoly- 12-tungstate CUW,,O,~~- is proposed as a model for these enzymic systems as the copper(I1) atom is tetrahedrally co-ordinated.228 It can be reversibly reduced to a Cu' species that is stable in aqueous solution with respect to disproportionation. Irradiation of copper(I1) P-diketonates in alcohols at 254 nm produces copper Photochemical production of Cu' is the first step in this reaction, followed by thermal decomposition. Copper(I1) carboxylates are reduced to copper(1) derivatives by the action of Ph3P in ethanol.,,' The products (Ph,P),-CuX or (Ph,P),Cu(biX) can be isolated (X and biX are carboxylates).A variety of tertiary phosphines have also been used to reduce copper(I1) nitrate.,,' The products [L,Cu(NO,)] [L,Cu(NO,)] and [L4Cu] (NO,) were shown by crystal-lographic methods to contain bidentate unidentate and ionic nitrate re-spectively (L = tertiary phosphine). In contrast to the preceding reactions, Cu"(biX) (biX = hexafluoroacetylacetonate) reacts with one equivalent of PR, in non-polar solvents to form dark green adducts Cu(biX),PR (R = Ph,, Et, Bu," Ph,Me or PhMe,).,, These complexes are the first substantiated phosphineecopper(I1) derivatives. They are monomeric in chloroform and have magnetic moments in the range 1.65-1.76 BM. Excess phosphine causes reduction to Cu'(biX)(PR,) .The N macrocycle 5,11,16,22-tetramethyl-6,10 17,2 1 -dinitrilodibenzo[b,m]-[ 1,4,12,15]tetra-azacyclodocosine (lo) prepared by the acid-catalysed Schiff-base (10) condensation of 2,6-diacetylpyridine with o-phenylenediamine reacts with two equivalents of Cu(N03) in ethanol to give [Cu",(sexiL)] (NO,) . Models suggest that the two copper atoms should lie about 264 pm apart similar to the D. R. Wexell and M. T. Pope Chem. Comm. 1971 886. 2 2 9 H. D. Gafney and R. L. Lintvedt J . Amer. Chem. SOC. 1971,93 1623. 2 3 0 B. Hammond F. H. Jardine and A. G. Vohra J . Inorg. Nuclear Chern. 1971 33, 1017. *" W. A. Anderson A. J. Carty G. J. Palenik and G. Schreiber Canad. J . Chem. 1971, 49 761. 2-'2 R . A. Zelonka and M. C. Baird Chem. Comm.1971 780 400 R . J . Cross and J . M . Winjield distance found in the copper(@ acetate dimer. The magnetic moment of 1.80 BM at room temperature falls to 1.40 BM at 96.8 K. An increasing positive deviation from the Curie-Weiss law is found below 150 K. These data suggest a weak metal-metal interaction and this is the first example of a macrocyclic ligand holding two metals together to allow such interactions.233 The crystal structures of the two dinuclear complexes dichloro-[“’-ethylene-bis(salicylideneiminato)copper(~~)]copper(~r) ( 1 1) and dichloro-[NN’-propylene-bis(salicylideneiminato)copper(~~)]copper(~r) (12) show that relatively small changes in the stereochemistry of one copper atom can effect drastic changes at the other.234 Complex (1 1) contains five-co-ordinate pyramidal copper by bonding to a chlorine which is part of a neighbouring molecule.The equivalent copper atom in (12) is pseudotetrahedral. C1 W ( 1 1) (12) Silver and Gold.-When Ag2C0 is heated at 400 K the silver(r) oxide formed is extremely active to CO uptake.235 The activity does not appear to depend mainly on surface area but is connected with the availability of moisture at the reaction interface. When very dry CO is used the Ag20 is rapidly desensitized. The hitherto unknown silver(r1) fluorides MAgF (brown; M = K Rb or Cs) md K,AgF4 (violet) have been isolated. The former compounds are structurally :elated to KCuF,. The compounds are prepared by fluorinating silver sulphate at high temperature^.^,^ Related compounds were described last year.The dinuclear complex [Au(S2CNBui2)] is known to have a gold-gold jistance of 276 pm. The Raman spectrum2,’ of the dimer in chloroform allows the assignment of an Au-Au symmetrical stretching mode which suggests a netal-metal bond-strength about that of Au02. The metal-metal interaction :an be explained in terms of charge transfer from the dithiocarbamate ligands to 4u’ which increase its electron density sufficiently to form the partial bond. The crystal structures of more gold cluster compounds have been reported ind their geometry has been rationalized. The complex [ A ~ ~ ( P ( o - t 0 1 ) ~ ) ~ ] (PF6)3 1s a representative of a large class of [Au,L,I3+ derivatives.238 A central gold ”’ R. W. Stotz and R. C. Stoufer Chem. Comm. 1970 1682. z34 C .A. Bear J. M. Waters and T. N. Waters Chem. Comm. 1971 703. ”’ P. A. Barnes M. F. O’Connor and F. S. Stone J . Chem. SOC. ( A ) 1971 3395. 2 3 6 R.-H. Odenthal and R. Hoppe Monafsh. 1971 102 1340. 1 3 ’ F. J. Farrell and T. G. Spiro Znorg. Chem. 1971 10 1606. 238 P. L. Bellon F. Cariati M. Manassero L. Naldini and M. Sansoni Chem. Comm., 1971 1423 The Transition Elements 40 1 atom is attached to eight AuL units and each of these AuL links is joined by gold-gold bonds to three other similar units. The mean Au-Au distance (280 pm) is shorter than that found in gold metal (288 pm). Two isomers of the dicyanodithiocyanatogold(II1) anion both isolated as their salts with K+ or Et,N+ are believed from their i.r. and u.v.-visible spectra to be [Au(CN),(SCN),]- and [Au(CN),(NCS),]-.The former is more stable. These are the first linkage isomers reported for gold(111).~~~ The first example is also reported240 of the 'symmetrization' reaction Au' + Au"'-+ 2Au". The Au'-Au"' material (PhCH,),SAuX,(PhCH,),SAuX (X = C1 or Br) is treated with the lithium salt of cis-l,2-dicyanoethylenedithiolate (two equivalents per gold atom) in the presence of [Bu",N]+. The pale-green precipitate is identical with speci-mens of [BU"~N],[AU(~~X)~] produced by the BH,- reduction of a gold(II1) complex of the same ligand. 12 The Zinc Group The crystal structure of (py),Zn(NO,) reveals the presence of bidentate but asymmetrically bonded nitrates and the monomeric units contain seven-co-ordinate zinc.241 Four of the bonds in an approximately square configuration (20,2N) are significantly shorter than the other three.The structure of (py),-Zn(NO,) has also been determined by X-ray cry~tallography.~~~ In this species the nitrates are asymmetrically unidentate leading to pseudotetrahedral zinc. Bis-(j3-aminomercapto) complexes of zinc(1r) and cadmium(I1) have been prepared to investigate the inversion rates of the tetrahedral enantiomers (A A).243 The methyls of N-isopropyl groups are diastereotopic and the progress of the inversion was followed using variable-temperature 'H n.m.r. spectroscopy. Inversion at zinc is appreciably slower than inversion at cadmium (the activation energies are 88 kJ mol- ' and 56-7 kJ mol-' respectively). The rate of ligand exchange at Zn is low compared to the inversion rate but the two processes are similar in rate for the Cd compound.This may mean that a bond-rupture mechanism rather than a true inversion operates at cadmium. The 'P n.m.r. spectra of L2CdI (L = tertiary phosphine) allow the measure-ment of J("'Cd-3'P) and J("3Cd-31P). The Cd-P bonds are weaker than the Hg-P bonds in analogous mercury compounds and cooling is necessary to lower the rate of phosphine exchange.244 The value of J decreases as the number of phenyl groups on phosphorus increases. This is similar to results on the mer-cury compounds. The existence of the species Hg3,+ was reported last year and this year com-pounds containing both Hg32+ and Hg6,+ have been isolated and examined. Mercury reacts with AsF in liquid SO to produce Hg,(AsF,),. This pale-yellow solid has been examined crystallographically by X-rays and a linear 2 3 9 D.Negoiu and L. M. Bfiloiu Z. anorg. Chem. 1971 382 92. 2 4 0 J. H. Waters T. J. Bergendahl and S. R. Lewis Chem. Comm. 1971 834. 2 4 1 A. F. Cameron D. W. Taylor and R. H. Nuttall Chem. Comm. 1971 129. 2 4 2 A. F. Cameron D. W. Taylor and R. H. Nuttall J. Chem. Soc. ( A ) 1971 3402. 2 4 3 S. S. Eaton and R. H. Holm Inorg. Chem. 1971,10 1446. 2 4 4 B. E. Mann Inorg. Nuclear Chem. Letters 1971 7 595 402 R . J . Cross and J . M . Winfield symmetrical Hg3,+ unit with Hg-Hg at 255 & 1 pm-was discovered.245 v(Hg-Hg) is 118 cm- in liquid SO,. When mercury is dissolved in fluorosulphuric acid a polarized Raman line at 133 cm-' indicates again the presence of Hg3,+. A closer examination246 of the reaction of mercury and AsF in liquid SO reveals that the first stage is to produce an insoluble yellow compound Hg,'+(AsF&.This compound has an absorption band at 360nm. It reacts further in SO or HS0,F to yield the Hg32+ derivative. A species with Hg*+ can also be made from the reaction of mercury with antimony pentafluoride : 6Hg + SSbF Hg6(SbzFl,) + SbF, A redetermination2,' of the mercury-mercury bond lengths in Hg,X [X = F, C1 or Br] shows that contrary to general belief there is no significant correlation with the electronegativities of X. Co-ordination complexes between HgX (X = C1 Br or I) and 2-methoxy-carbonylphenyl-di-R-arsines (R = methyl phenyl or p-tolyl) are formulated HgX,L. These are non-electrolytes and appear to be pseudotetrahedral with L acting as a chelating ligand from As and the carbonyl group of the ester The chlorine n.q.r.spectra of more HgCl complexes have been recorded.,,' A clear correlation between the n.q.r. frequency v(Hg-Cl) and the Hg-C1 bond length is observed and the dependence of the n.q.r. spectra on the degree of covalent bonding is apparent. 13 Ligands Infrared and Raman spectroscopic examinations of the compound Cu(py),(PF,), indicate that the symmetry of the PF,- ion is less than octahedral and weak co-ordination between PF - and copper(I1) is postulated.250 The complexes Ni(py),(PF& Ni(py),(PF,) and Ni(4-Mepy),(PF6) have also been isolated and the magnetic moments and i.r. and electronic spectra of all four hexafluoro-phosphate compounds suggest,,' that any co-ordinating ability of PF6- is less than that of C104- or BF,-.The complexing tendency of trifluoromethane-sulphonate has received attention also.252 Using chromium(II1) as acceptor, the species Cr(CF,S03)(aq)2 + has been isolated by ion-exchange methods. The behaviour of this ion towards aquation is intermediate between that of Cr(NO,)(aq),+ and Cr(C10,)(aq)2f and the ligand CF3S03- holds some promise as a weakly co-ordinating species. Simple rules based on the theory of hard and soft acids and bases are proposed to rationalize ligand-exchange processes between metals and metal-catalysed 245 C . G . Davies P. A. W. Dean R. J . Gillespie and P. K. Ummat Chem. Comm. 1971, 2 4 6 R . J. Gillespie and P. K. Ummat Chem. Comm. 1971 1168. 247 2 4 8 S. S. Sandhu and H.Singh J . Inorg. Nuclear Chem. 1971 33 97. 2 4 y 2 s o S. A. Bell J . C . Lancaster and W. R. McWhinnie Inorg. Nuclear Chem. Letters 1971, 2 s 1 2 s 2 782. E. Dorm Chem. Comm. 1971,466. D. E. Scaife Austral. J . Chem. 1971 24 1753. 7 405. H. G. Mayfield jun. and W. E. Bull J . Chem. SOC. ( A ) 1971 2279. A . Scott and H . Taube Inorg. Chem. 1971 10 62 The Transition Elements 403 exchange reaction^.^ 5 3 Numerous examples are cited and the rules predict favourable processes as well as providing a convenient classification of known reactions. The ligand properties of the organic pseudohalides C6F50- C6C150-, CH,COS- CF,COS- C6F5S- and PhS- and the carbodi-imides 2,4,6-trichlorophenyl-NCN- and o-chlorophenyl-NCN- have been compared.254 Four-co-ordinate complexes of Co" Nil1 Cu" and Zn" have been isolated with cations of the type Et4N+ or Ph4Asf and their magnetic moments and u.v.-visible spectra recorded.The ligands all have A values greater than those of the halide ions but less than NCO- or NCS-. Their nephelauxetic effects are not regular. High values of electronegativity in ligands of this type lead to higher co-ordination numbers and higher symmetry.255 Optical Stereochemistry.-A book on the absolute configuration of metal complexes has appeared,256 and applications of c.d. measurements to problems on metal-ion complexes have been reviewed using Nil' and lanthanide complexes as examples.257 Conformational analyses of M(en),"+ ions have been discussed and related to the effects of M size.258 Regional rules correlating optical activity of d + d transitions -with the substituent positions for chiral Co"' complexes with the tetragonal chromo-phores [CoA,B] or trans-[CoA4B2] or the octahedral [CoA,] have been re-ported in full.In the latter case the contributions to optical activity of the configuration of the chelate rings about Co and that of the conformation of each ring are distinguished by individual rules. Possible electronic mechanisms for the basis of the rules are discussed.259 A similar study of the rules governing the signs and relative magnitudes of the rotatory strengths of ligand-field transi-tions in tetragonal complexes adopts a model in which the complex is partitioned into three separate parts.260 These parts are (i) the o-bond structure of MA4B2, (ii) the n-orbitals of the ligands and (iii) the non-ligating parts of the ligands and the contribution of each is assessed.The absolute configuration of (-)-stilbene-diamine is (R,R) and the c.d. spectra of cobalt(II1) complexes of this ligand are consistent with a dynamic coupling or polarizability mechanism for the conforma-tional optical activity due to chirally-puckered chelate rings.26 l A static-field mechanism in which the activity arises from the charges on the ligand atoms is ruled out. NN'-Disalicylidene-( - )-propane- 1,2-diaminecopper(11) has a dominant posi-tive Cotton effect in solution and a negative one in the solid phase. Both the 2 5 3 M. M. Jones and H. R. Clark J. Inorg. Nuclear Chem. 1971,33 413. 2 5 4 B. R. Hollebone and R. S.Nyholm J. Chem. Soc. (A) 1971 332. 2 5 5 B. R. Hollebone J. Chem. SOC. ( A ) 1971 481. s 6 C. J. Hawkins 'Absolute Configuration of Metal Complexes' Wiley-Interscience, New York 1971. 'ST L. I. Katzin Co-ordination Chem. Rev. 1970 5 279. 2 5 8 J. K. Beattie Accounts Chem. Res. 1971 4 253. 2 5 9 S. F. Mason J. Chem. SOC. (A) 1971 667. 2 6 0 F. S. Richardson J. Chem. Phys. 1971,54 2453. 2 6 ' P. L. Fereday and S. F. Mason Chem. Comm. 1971 1314 404 R. J. Cross and J. M . Winjield dehydrated form and the monohydrate have the same c.d. spectra.262 The interpretation of these results confirms that a double-octant rule is necessary for rigorous treatment. The magnetic c.d. spectrum of [Co1412- has been used as a test of ligand-field assignments. The assignments are based on a molecular orbital analysis of electron repulsion and spin-orbit Free-energy differences have been calculated for a number of [M(en),] complex ion configurations and their variations with M-N bond lengths have been The preference for the configurations ~-(666) L-(M) ~ - ( 6 6 A ) , and L-(U~) which is apparent at M-N z 200 pm disappears when M-N increases to ca.230 pm. Lowest-energy transitions for ring inversions have also been calculated. These are of the envelope type and require energies of ca. 21.0 kJ mol-’ at bond distances of 200 pm to ca. 29.4 kJ mol-’ at 230 pm. The results of these calculations have been used to explain the room-temperature n.m.r. spectra which are interpreted in terms of rapid ring inversions. The induction of c.d. by asymmetric environments was mentioned last year.Reports this year include c.d. spectra of [c0(NH,),l3 + induced by dissymmetric anions (such as a-bromocamphor-n-sulphonate) in the solid A model for such ion-pair interactions is proposed in the complex ion [Co(sexiL)I3+ [sexiL = MeC(CH2NHCH2CH,NH2),].266 The c.d. spectrum of this ion resembles that of [Co(en),13 + in the presence of the - anion and a compari-son illuminates the perturbations of the c.d. spectra caused by inactive anions by outer-sphere complexation. A method for obtaining the assignments of hidden or very mixed transition bands by measuring the c.d. spectra of oriented films has been The same technique can provide information on the arrangement of outer-sphere ‘ligands’.268 The temperature dependence of the c.d.spectra of ( +)-[(biL),CoI3+ in solution and ( +)-[(biL),Co]Br ,H20 in the solid state indicates conformational equilibria between tris-skew-boat and tris-chair forms favouring the latter by 2-0 kJ mol- ’ (biL = trirneth~lenediamine).~~~ The X-ray crystal structure of [Co(en),]-[cu2c18]cl ,2H20 shows an anion consisting of two distorted trigonal-bi-pyramidal units with two bridging chlorides and the cation in a 266 configura-t i ~ n . ~ 7 0 This high-energy configuration is presumably imposed by crystal packing interactions. Halides.-The chemical reactivity of high-oxidation-state transition-metal fluorides has been discussed in relation to their thermodynamic proper tie^.^' 2 6 2 263 B. D. Bird J. C. Collingwood P. Day and R. G. Denning Chem.Comm. 1971 225. 2 6 4 J. R. Gollogly C. J. Hawkins and J. K. Beattie Znorg. Chem. 1971 10 317. 2 6 5 B. Basnich and J. M. Harrowfield J . Amer. Chem. SOC. 1971 93 4086. 2 6 6 J. E. Sarneski and F. L. Urbach J . Amer. Chem. SOC. 1971,93 884. 2 6 7 R. Larsson and B. Norden Acta Chem. Scand. 1970,24,2681. 2 6 8 B. Norden Acra Chem. Scand. 1971 25 357. 2 6 9 P. G. Beddoe M. J. Harding S . F. Mason and B. J. Peart Chem. Comm. 1971 1283. 270 D. J. Hodgson P. K. Hale and W. E. Hatfield Inorg. Chem. 1971 10 1061. 2 7 1 T. A. O’Donnell Rev. Pure Appl. Chem. (Australia) 1970 20 159; N. P. Galkin and Yu. N. Tumanov Russ. Chem. Rev. 1971 40 154. R. D. Gillard S . H. Lawrie and R. Ugo J . Inorg. Nuclear Chem. 1971,33 997 The Transition Elements 405 The recent controversy over the molecular structure of pentafluorides in the liquid and vapour states in which the presence of monomers and polymers has been variously proposed has been resolved to a great extent by an elegant mass-spectromeric A molecular beam source was used to eliminate ion-molecule reactions and ions due to polymeric species (MF,) were observed for Ir (up to n = 5) and Nb and Ta (up to n = 4) pentafluorides.In contrast VF, and CrF have monomeric vapours. The presence of polymers in gaseous NbF, and TaF is proposed also from their Raman spectra.272b Single-crystal X-ray work has confirmed that OsF is isostructural with RuF, the (OSF,) units featuring non-linear 0s-F-0s bridges.273 IrF has a similar structure so the observation of (IrF,) + in the vapour Several reports274 have been concerned with the vibrational spectra of MX, (M = Ti Zr or Hf; X = C1 Br or I) molecules in the gaseous liquid and solid states.A previous suggestion that TiCl is dimeric in the liquid state has been shown to be incorrect and & symmetry for TiX in both solid and liquid states is indicated. The M -X bond stretching force-constants are virtually independent of M but show the expected dependence on X and are in the order M-C1 > M-Br > M-I. The mixed halides TiBr,-,Cl (n = 1-3) are formed in TiBr,-TiCl mixtures and halogen exchange is almost random. bond angles of 180 & 10" are suggested from an i.r.-spectroscopic study of matrix-isolated MCl molecules (M = Sc Ti V Cr Mn Fe or Ni).275 Mixed hexa-halogenometallates derived from TiX or Nb(Ta)X (X = F C1 or Br) are readily formed,276 and are often identified in solution by n.m.r.spectroscopy (e.g. 19F or 93Nb). Typically isomeric species are present and redistribution of halide ligands among a series of anions is random. As usual ternary fluorides have attracted considerable attention. Square-planar co-ordination for Cr" and Cu" has been found from single-crystal X-ray work on Sr,CuF, SrMF, and C ~ C U F ~ ~ and the electronic spectra of SrMF, have been assigned on this basis.278 The electronic spectra and ligand-field parameters of tetragonal metal fluorides and hexafluoro-complexes of 3d ele-ments have been reviewed,.and it is concluded that a purely electrostatic model is is of particular interest. 2 7 2 ( a ) M. J. Vasile G. R. Jones and W.E. Falconer Chem. Comm. 1971 1355; (b) L. E. Alexander Znorg. Nuclear Chem. Letters 1971 7 1053. 2 7 3 S. J. Mitchell and J . H. Holloway J . Chem. SOC. ( A ) 1971 2789. 2 7 4 R. J . H. Clark B. K. Hunter and C. J. Willis Chem. Comm. 1971,201 ; R . J. H. Clark and B. K. Hunter J . Chem. SOC. ( A ) 1971 2999; R. J. H. Clark B. K. Hunter and D. M. Rippen Chem. andZnd. 1971,787 ; R. J. H. Clark and C. J. Willis Znorg. Chem., 197 1 10 1 1 18; H. F. Shurvell J . Mof. Spectroscopy 1971 38 431 ; W. Kiefer and H. W. Schrotter 2. Naturforsch. 1971 25b 1374; R. J . H. Clark and C. J. Willis, J . Chem. SOC. ( A ) 197 1 838. 2 7 5 J . W. Hastie R. H . Hauge and J. L. Margrave High Temp. Sci. 1971 3 257. 2 7 6 L. Kolditz and R. Malzahn Z . unorg. Chem. 1970 379 279; Yu.A. Buslaev E. G. Ilin S. V. Bainova and M. N. Krutkina Dokludy Akad. Nuuk S.S.S.R. 1971,196,374; Yu. A. Buslaev E. G. Ilin and M. N. Krutkina ibid. 1971 200 1345; 201,99; Yu. A. Buslaev V. D. Kopanev and V. P. Tarasov Chem. Comm. 1971 1175. 2 7 7 H. G. von Schnering B. Kolloch and A. Kolodriejczyk Angew Chem. Znternat. Edn., 1971 10 413. 2 7 8 D. Durnora C. Fouassier R. von der Muhll J. Ravez and P. Hagenrnuller Compt. rend. 1971 273 C 247 406 R. J . Cross and J . M . Winfield inadequate for these compounds.279 A similar conclusion is reached from the e.s.r. spectra of V2+ Cr3+ and Ni2+ doped into alkali-metal fluoride lattices.280 Vibronic structure associated with the ,E -+ ,A2 transition in CSzMnF and Cr3 + doped into K2NaGaF6 indicates that a second-order Jahn-Teller effect operates in the states of these compounds.It arises from mixing with "Tg states this mixing being much larger for Cr"' than for Mn'V.281 The ability of complex fluorides to fluorinate organic compounds is well established but other reactions have been little studied. Their potential is illustrated by the evolution of F from solutions of K,CuF6 or Cs2CoF6 in anhydrous HF at 273 K and by the oxidation of Xe to XeF by K,NiF under similar conditions. MI IF,^-and NiF6,- are solvolysed by AsF in HF to give MnF and impure NiF,.282 Substituted derivatives of transition-metal halides reported this year include Ti14-n(NR2), (R = Me or Et; n = 2 or 3) and WF,NEt, which are believed to be halide-b~-idged.'~ The presence of C1 bridges in TiCl,(NEt,) has been con-firmed by X-ray work.The structure is [Ti(NEt,)ClCI,,,] and the Ti-N distance of 185.2 pm is shorter than that expected for a single bond284 (cf. below). Dialkylamides and Related Complexes.-Complexes derived from these ligands, which may be regarded as n-donors are often co-ordinatively unsaturated and recent activity in the area has been maintained this year. The co-ordination geometries of Nb(NMe,) and Nb(piperidinate) are similar and they may be regarded as distorted tetragonal pyramids where the distortion tends towards trigonal-bipyramidal geometry. From a consideration of Nb-N bond lengths alone in each molecule only the axial Nb-N bond has significant ~c-character.,~, The spectroscopic and magnetic properties of M'V(NR2)4 (M = Nb Cr or Mo) have been interpreted on the basis of a distorted tetrahedral ( D 2 J geometry for the MN group,286 and a similar situation obtains for Cr(OR), when R = t-alkyl or SiEt3.287 Complexes M(NR,),(M = Cr or Mo) are prepared via the dis-proportionation of the corresponding M"' compounds,286b,c similar reactions having been reported for Ti"' and V"' previously (see 1969 Report).Approximate D symmetry for Cr(NPr',) has been confirmed by X-ray crystallography,288" and the magnetic and spectroscopic properties of 2 7 9 280 281 282 283 284 285 286 281 288 D. Oelkrug Structure and Bonding 1971 9 1 ; G. C. Allen and K. D. Warren ibid., p. 49. L. Shields J . Chem. SOC. ( A ) 1971 1048. C. D. Flint Chem. Phys. Letters 1971 11 27. T. L. Court and M. F. A. Dove Chem.Comm. 1971,726. H. Burger C. Kluess and H.-J. Neese Z . anorg. Chem. 1971 381 198; A. Majid, R. R. McLean D . W. A. Sharp and J. M. Winfield ibid. 1971,385 85. J. Fayos and D. Mootz Z . anorg. Chem. 1971,380 196. C . Heath and M. B. Hursthouse Chem. Comm. 1971 143. ( a ) D. C. Bradley and M. H. Chisholm J . Chem. SOC. ( A ) 1971 151 1 ; ( b ) J. S . Basi, D. C. Bradley and M. H. Chisholm ibid. p. 1433; (c) D. C. Bradley and M. H. Chisholm ibid. p. 2741. E. C. Alyea J. S. Basi D . C. Bradley and M. H. Chisholm J . Chem. SOC. ( A ) 1971, 772. ( a ) D. C. Bradley M. B. Hursthouse and C. W. Newing Chem. Comm. 1971 411; ( 6 ) E. C. Alyea D . C. Bradley R. G. Copperthwaite K. D. Sales B. W. Fitzsimmons, and C. E. Johnson ibid. 1970 1715; ( c ) D. C. Bradley and R.G. Copperthwaite ibid., 1971 764 The Transition Elements 407 Fe[N(SiMe,),] whose structure was reported in 1969 have been interpreted on the basis of a high-spin d5 species in D, symmetry.288b A similar symmetry is suggested for Ti"' and V"' in M[N(SiMe,),] .288c Co[N(SiMe,),] has been reinvestigated and from its molecular weight electronic spectra and magnetic susceptibility is believed to contain two-co-ordinate Co". A linear N-Co-N group is indicated.289 The attempted preparation of Co(NEt,) from CoCl and LiNEt, however leads to the formation of a NN'-diethylbutane-l,3-di-iminato-complex (13) for which a pseudotetrahedral configuration about CO" is sug-gested. 90 EtN NEt \ / c o / \ EtN (13) On demetallation of (13) EtN CHCH C(Me).NHEt and its hydrochloride are produced from which the Zn" derivative can be prepared.The ligand gives rise to a very large ligand field. Other compounds related to M(NR,) that have been described include M[(R,Si)N.N(SiR,),] (M = Zn Cd or Hg)291 and azomethine complexes e.g. (n-Cp)Ti(N CR,)Cl (R = alkyl aryl or CF,).292 The (CF3),C=N- ligand is a potential H-acceptor as trans-(Ph,P),Pt[N C(CF,),]H can isomerize to (1 4). 29 2 b Ph,P NH 'Pt/ I Other Nitrogen Ligands.-Methyldiazine MeN=NH reacts with copper(1) chloride to yield a red-brown diamagnetic complex ( M ~ N N H ) C U C ~ . ~ ~ ~ The structure of the adduct is unknown but it is certainly polymeric. The compound inflames in oxygen but is thermally stable to 300 K. The ligand is released when the complex is treated with CN-.Related cis-azoalkane complexes of copper(1) are made by the oxidation of semicarbazides by CUCI,.,~~ This single-stage 2 8 9 D. C. Bradley and K. J . Fisher J . Amer. Chem. Soc. 1971,93 2058. 2 9 0 R . Bonnett D. C. Bradley K. J. Fisher and I . F. Rendall J . Chem. Soc. ( A ) 1971, 2 9 1 K. Seppelt and W. Sundermeyer Chem. Ber. 1970 103 3939. 2 9 2 ( a ) M. R. Collier M. F. Lappert and J. McMeeking Znorg. Nuclear Chem. Letters, 1971 7 689; ( 6 ) B. Cetinkaya M. F. Lappert and J. McMeeking Chem. Comm., 1971 215. M. N. Ackermann Znorg. Chem. 1971 10 272. 1622. 2 9 3 2 9 4 M. Heyman V. T. Bandurco and J. P. Snyder Chem. Comm. 1971 297 408 R . J . Cross and J . M . Winfield reaction produces high yields and is a convenient synthetic route.The ligand is liberated from copper by OH-. H O R3HN-CO-R'N-NHR2 + CUCI 4 [(R'N=NR2)CuC1] + R3NC0 + HCI Azobenzene (L) complexes of nickel(0) have been made by displacing neutral ligands such as tertiary phosphine olefin or t-butylisocyanide from Nio com-plexes or by reducing the nickel@) compounds (R,P),NiX with lithium in the presence of L.295 The products (R,P),NiL have been compared to the analo-gous olefin derivatives (R,P),Ni(olefin). The reactions of hydrazine with transition-metal complexes have been re-viewed.296 Some of these reactions produce nitrogen or nitrogen complexes. This year the formation of hydrazine from molecular nitrogen under mild conditions has been reported297 (see also Introduction). The reaction of the Grignard reagent Pr'MgC1 with (Ph,P),FeCI in ether in the presence of N, leads to a nitrogen complex believed to be (Ph,P),(Et,O)HFe(p-N,)Fe(PPh,),-OEt,.The reaction of this dinuclear complex with dry HCI leads to N2H4 in yields of ca. 10%. Investigations continue on metal complexes of nitrogen heterocycles. The X-ray crystal structure of the trinuclear nickel complex { [Ni(H,0),(C,N3H3),],-Ni} (NO,) ,(H,O) [C,N,H = 1,2,4-triazole (15)] has been determined.298 The 'terminal' nickel atoms are fuc-[(H,O),Ni(L),] units and the triazole ligands (L) bridge to the central nickel atom by nitrogen atoms 1 and 2 to give octahedral N, co-ordination at that atom. The crystal structure of L,ZnCl [L = l-methyl-tetrazole (16)] reveals the expected distorted tetrahedron at zinc.299 The zinc atom is coplanar with the rings which are attached at the 4-position.An n.m.r. investigation into the silver(1) complexes of 1,5-dimethyltetrazole (17) shows that species of stoicheiometry L,Ag+ are present in solution and L,Ag(ClO,) was isolated.300 The chemical shifts of the two methyl groups are very similar and this suggests that N(3) is the donor atom. Studies have also been continued on pyrazole (18) and imidazole (19) as ligands.,O1 The ligand-field spectra of the tetragonal complexes [L4MX2] [L = 3(5)-methylpyrazole; M = Mn" Fe", Co" Ni" or Cu"; X = NO, C1 Br or I) show large tetragonal distortions and this may be due to hydrogen-bonding between co-ordinated L and X weakening the M-X bond. The ligand-field parameters of N-n-butylimidazole complexes show this to be a stronger ligand than the unsubstituted imidazole.' l a Complexes [MLJX, 2 9 5 ( a ) H. F. Klein and J . F. Nixon Chem. Comm. 1971 42; (b) S. Otsuka T. Yoshida, and Y . Tatsuno Chem. Comm. 1971,67. 2 9 6 F. Bottomley Quart. Rev. 1970 24 617. 2 9 7 Yu. G. Borodko M. 0. Broitman L. Kachapina A. E. Shilov and L. Yu Ukhin, 2 9 8 G . W. Reimann and M. Zocchi Acta Cryst. 1971 B27 682. 2 9 9 N. C . Baenziger and R. J . Schultz Inorg. Chem. 1971 10 661. 3 0 0 D. M. Bowers R. H. Erlich S . Policec and A. I . Popov J . Inorg. Nuclear Chem., 301 ( a ) J. Reedijk J . Inorg. Nuclear Chem. 1971 33 179; (b) J. Reedijk Rec. Trav. chim., Chem. Comm. 1971 1185. 1971 33 81. 1970 89 993 The Transition Elements 409 (M = Ni or Cd) and ML,X (M = Cu) were examined (X = C104 BF, or NO,) and the pyridine-type nitrogen of the five-membered ring seems to be the point of attachment.The crystal structures of the adeninium (20) and guaninium (21) complexes LZnCl show that the zinc atom is attached through N(7)and N(9) re~pectively.~'~ The aniline and substituted-aniline complexes303 A[Ru"'X,L,] [Ru"L,]Br,, and [Ru"L,Br,] have been reported (A = Cs Me,N PhNH, or pyH; X = C1, Br or I). The A-values place aniline between en and H,O in the spectrochemical series. Reviews have been written on iron(I1) di-imines304 and related complexes, on the co-ordination behaviour of some chelating ligands containing non- or weakly-conjugated 2-pyridyl groups,3o5 and on steric effects in bis-pyridyl and bis-o-phenanthroline ~ornplexes.~'~ A geometrical analysis of the (as yet un-known) square-planar (biL),M and octahedral trans-(biL),MX species (biL = bipy or phen) suggests that the interaction between the hydrogen atoms near the ligating nitrogens will be high enough to prevent complex formation except, perhaps from third-row elements or others in very low oxidation states.," 3 0 2 L.Srinivasan and M. R. Taylor Chem. Comm. 1970 1668. 3 0 3 D. L. Key L. F. Larkworthy and J. E. Salmon J . Chem. SOC. ( A ) 1971,2583. 304 P. Krumholz Structure and Bonding 1971,9 139. 30s W. R. McWhinnie Co-ordination Chem. Rev. 1970 5 293. 3 0 6 E. D. McKenzie Co-ordination Chem. Rev. 1971 6 187. 3 0 7 L. H. Berka W. T. Edwards and P. A. Christian Inorg. Nuclear Chem. Letters, 197 1 7 265 410 R. J . Cross and J . M. Winjield 1.r.analysis studies of (biL)MX (biL = bipy or [2H8]bipy; M = Mn Fe Co Zn, Pd or Pt; X = CI or Br) has allowed the stretching force constants to be calcu-lated.308 Strong metal-nitrogen bonds are found for Pt" Pd" and Fe" but much weaker ones for Mn" Co" and Zn". The X-ray crystal structure of [Co(terL)Cl,] (terL = terpyridyl) reveals an approximately square-pyramidal configuration with a chlorine atom at the apex.309 The terdentate ligand shows significant distortions from planarity. Four- five- and six-co-ordinate complexes of Co" Ni" Zn" or Hg" with the ligands di-(2-pyridyl) disulphide and 1,2-di-(2-pyridyl)ethane have been iso-lated.310 The geometry depends mainly on the metal. For example only tetra-hedral cobalt complexes were obtained but the nickel derivatives were tetra-hedral square-planar or five-co-ordinate.In the latter cases the bidentate ligands span equatorial and apical sites. No sulphur co-ordination was detected except in the case of mercury. Reviews on metallo-p~rphyrins,~ ' ' c o r r i n ~ ~ l 2 and polymeric phthalocya-nine3 complexes have appeared. p-Sulphonated tetraphenylporphyriniron(II1) complexes are water-soluble. Both monomers and oxygen-bridged dimers exist in s ~ l u t i o n . ~ l4 Oxygen Donors.-The reaction of (Ph,P),RhCl in CH2Cl with molecular oxygen produces RhCl(O,)(PPh,) ,CH,Cl .3 A crystallographic investiga-tion showed this to be dimeric with bridging O2 in an unusual configuration (22). The methylene chloride molecules are disordered. Ph,P C1-Rh-0 0-Rh-Cl Ph,P ' "6' \PPh3 (22) The 0-0 distances within the two bridging groups are 144(2)pm and the distance of Rh(1) from 0(1) 0(2) and O(3) is 198(1) pm 219(1) pm and 207(1) pm, respectively.The 0 molecular ground-state corresponds to TC*~TC*' rather than TC*lTC*l The single-crystal polarized electronic spectra and the paramagnetic aniso-tropy of the square-pyramidal complexes [(P~,AsO)~N~NO,]NO and [(P~,AsO)~CONO~]NO~ at temperatures of 300 K and 77 K have been re-corded. The results have been interpreted in terms of a crystal-field framework. Extensive use of mapping procedures to identify regions of fit between theory 3 0 8 J. S. Strukl and J. L. Walter Spectrochim. Acta 1971 27A 223. 3 0 9 E. Goldschmied and N. C . Stephenson Acta Cryst. 1970 B26 1867. 3 1 3 1 2 A.W. Johnson Pure Appl. Chem. 1970 23 375. 3 1 3 A. A. Berlin and A. I. Sherle Znorg. Macromolecules Rev. 1971 I 235. 3 1 4 E. B. Fleisher J. M. Palmer T. S. Srivastava and A. Chatterjee J . Amer. Chem. Soc., 3 1 5 M. Keeton and A. B. P. Lever Znorg. Chem. 1971 10 47. P. Hambright Co-ordination Chem. Rev. 1971,6 247. 1971,93,3162. M. J. Bennett and P. B. Donaldson J . Amer. Chem. SOC. 1971,93 3307 The Transition Elements 41 1 and experiment was made thus avoiding a simple 'best fit' approach. l6 A series of complexes ML,X [M = Mg" Ca" Mn" Fe" Co" Ni" Cu" Zn" or Cd" ; L = PhP(O)(NMe,),; X = C1 ClO, or BF,] has been examined by i.r. spec-tro~copy.~" The results suggest oxygen as the donor atom in each case. Mossbauer and Raman spectra of [Fe(biX),] (biX = O,PCl,- or 0,PF2-)3'8 indicate a distorted octahedral environment about iron(u1).Whereas O,PCl -is oxygen-bonded both 0 and F atoms co-ordinate from O,PF,-. Ionic bonding is excluded by the Raman results. Two reviews of metal acetylacetonates have appeared this year. l 9 The available evidence suggests that delocalization is complete around the six-membered ring in all but the y-carbon-bonded complexes. The reactivities of [Cr(acac),] and [Co(acac),] towards nitration and formylation have been com-pared.,,' The cobalt complex is more reactive in both cases and this agrees with Hiickel calculations. Acetylacetone itself has received attention as a ligand. The crystal structure of [NiBr,(acacH),] shows a trans-octahedral structure with boat-shaped bidentate acacH groups.The ligands' dimensions support the presence of the ketonic form.,,' The corresponding manganese compound however shows a different structure [MnBr,,,(acacH),] . The acacH ligands are enolic and unidentate, lying trans above and below the plane of the (MnBr,) chain.,,, The temperature-dependence of the proton line-broadening of solvent water by [Ni(H,0),(terL)l2' (terL = tribenzo[b,f,j] [ 1,5,9]triazacyclodecine) has been examined by n.m.r. spectroscopy. This fused-ring ligand produces no unusual effects compared to water exchange at other nickel(r1) complexes and it is con-cluded that no large change in the bond angles at nickel occurs in the transition state.,, The 'H n.m.r. spectra of the paramagnetic ions [Ni''(biL),]'+ and [Co"(biL),I2+ (biL = 2'2'-bipyridyl "'-dioxide) are reported.,, The isotropic shifts are attributed to dominant n-delocalization into the rings.The rings are 'tipped' at 67" to each other. Structural aspects of co-ordinated nitrates have been reviewed.325 Bubbling hydrogen through a solution of RhC1,,3H2O in DMSO provides a simple means of preparation of [RhCl,(DMSO),]. This moderately air-stable rhodium(1r) derivative is a useful source for preparing other Rh" complexes. The 3 1 h ' 3 1 8 J. Pebler and K. Dehnicke Z . Naturforsch. 1971 26b 747. 3 1 9 ( a ) D. W. Thompson Structure and Bonding 1971 9 27; ( 6 ) B. Bock K. Flatau, H. Junge M. Kuhr and H. Musso Angew. Chem. Znternat. Edn. 1971 10 225. 3 2 0 T. Shirado E. Gennari R. Merello A. Decinti and S . Bunel J . Znorg. Nuclear Chem., 1971,33 3417.3 2 1 S. Koda S . Ooi H . Kuroya K. Isobe Y . Nakamura and S. Kawaguchi Chem. Comm. 1971 1321. 3 2 2 S. Koda S. Ooi H . Kuroya Y . Nakamura and S . Kawaguchi Chem. Comm. 1971, 280. 3 2 3 J. E. Letter jun. and R. B. Jordan J . Amer. Chern. SOC. 1971 93 864. 3 2 4 I . Bertini D. Gatteschi and L. J. Wilson Znorg. Chim. Acta 1970 4 629. M. Gerloch J. Kohl J. Lewis and W. Urland J . Chem. SOC. ( A ) 1970 3269 3283. M. W. G . de Bolster and W. L. Groeneveld Rec. Trav. chim. 1971,90 11 5 3 . 3 2 5 C. C. Addison N. Logan S . C. Wallwork and C . D. Garner Quart. Rev. 1971 25, 289 412 R . J . Cross and J . M . Winfield single v(Rh-C1) in the i.r. spectrum suggests a tr~ns-structure.~~~ Attempts to replace co-ordinated C1- by I - in [CoCl,(biL),]+ (biL = en or propylenedia-mine) in DMSO led instead to the isolation of [Co(DMSO),I,]I.Strong bonding is suggested for the DMSO as chelating ligands were replaced.327 1.r. investiga-tions suggest 0-bonding. Sulphinato-complexes have been reviewed and examples listed of RS0 -bonding to metals through 0 S S and 0 or two 0 atoms.328 The ligand-field absorption and emission spectra of the 0,O'-bonded complexes [M"'(O,SR),] (M = V Cr or Fe ; R = Me Ph or p-tol) suggest that RS02- falls near to DMSO in the spectrochemical series.329 An interesting bond-isomerism is apparent in a sulphinatoiron(I1) complex. The complex [(p-tolSO,),Fe(OHz),] reacts with bipy to give [(bipy)Fe(O,S-p-tol),] in THF [(bipy),Fe(O,S-p-tol),] in py or [(bipy),Fe](O,S-p-tol) in water.330 Both 0- and S-bonded [(bipy),Fe(O,S-p-to]),] can be isolated.Other Ligands.-The bonding of thiocyanato-groups to metals has been dis-cussed in terms of a polyelectronic perturbation theory.33' A change in the bonding mode of CNS- to Cur' is reported when the co-ordination number at copper changes.332 Whereas [(biL),Cu(SCN),] has tetragonally distorted octahedral co-ordination with Cu -S bonds [(biL),CuSCN]ClO is five-co-ordinate with N-bonded thiocyanate (biL = 1,3-diaminopropane). The bonding mode of SCN- to Co"' in trans-[(biX),Co(py)(SCN)] (biX = dimethylglyoxi-mato) is not thermodynamically controlled by the nature of the solvent as reported last year. The effect of the solvent is kinetic.333 Electron transfer between an "00-Schiff-base complex of cobalt(r1) and similar complexes of methylcobalt(1rr) is accompanied by a shift of the methyl group from one cobalt to the The new ligands 2,6-bis-(2-dipheny1pho~phinoethyl)pyridine~ and 2,6-bi~-(2-diphenylphosphinomethyl)pyridine~~~ both allow isolation of five-co-ordinate complexes M(terL)X (M = Fe" Co" or Ni"; X = C1 Br I or SCN).Their electronic spectra suggest that the former ligand produces distorted trigonal-bipyramidal species whereas the latter favours distorted square pyra-mids. Magnetic susceptibility measurements between 80 and 400 K found examples of both low-spin and high-spin configurations as well as examples showing spin-isomerism These latter are the first examples of five-co-ordinate 3 2 6 B. R. James E. Ochiai and G . I. Rempel Inorg. Nuclear Chem. Letters 1971 7 , 781.3 2 7 M. Muto M. Yamaguchi and H. Yoneda Bull. Chem. SOC. Japan 1970 43 3935. 3 2 8 G. Vitzthum and E. Lindner Angew. Chem. Internat. Edn. 1971 10 315. 3 2 9 E. Konig E. Lindner I. P. Lorenz G . Ritter and H. Gausmann J. Znorg. Nuclear Chem. 1971,33 3305. 330 E. Lindner I. P. Lorenz and G . Vitzthum Angew. Chem. Internat. Edn. 1971 10 193. 3 3 1 A. H. Norbury J . Chem. Soc. ( A ) 1971 1089. 3 3 2 M. Cannas G. Carta and G. Marongiu Chem. Comm. 1971 673. 3 3 3 R. L. Hassel and J. L. Burmeister Chem. Comm. 1971 568. 3 3 4 A. van den Bergen and B. 0. West Chem. Comm. 1971,52. 3 3 5 W. S. J. Kelly G. H. Ford and S . M. Nelson J . Chem. Soc. ( A ) 1971 388. 3 3 6 W. V. Dahlhoff and S . M. Nelson J . Chem. SOC. ( A ) 1971 2184 The Transition Elements 41 3 d6 d7 and d8 complexes to show magnetic cross-over phenomena.Five-co-ordinate cobalt(II1) complexes [Co(quadriX)R,P]ClO (quadriX = salen or substituted salen) have been isolated and assigned square-pyramidal configura-t i o n ~ . ~ 3 7 The thermodynamic trans-effects of the tertiary phosphines were indicated by the formation constants of [Co(quadriL)(PR,)(NO,)] from these complexes. These correlate with the Taft o* coefficients for the phosphines, and the trans-effect trend in [Co(quadriL)L(H,O)]+ follows the order L = R,P > R > OH- > H,O (R = organic group). A series of complexes (biL),M" where biL is the bidentate ligand (23) has been isolated (M = Fe Co Ni Zn Pd or Pt; X = S ; R = Me or Ph.M = Co or Ni; X = NH; R = Ph .M = Co; X = 0; R = Ph).338 The sulphur complexes of Fe" Co" and Ni" include the first with a tetrahedral MS core (see 1969 Re-port).3 39 The crystal structure of bis(dithiotropolonato)nickel(II) shows a planar mole-cule with nickel at the centre of symmetry and Ni-S distances of 214.7(3) prn.,,' The C-C bond common to both the tropolone and chelate rings is significantly longer [144.8(4) pm] than the others [137.8-140.1(4) pm].This is in keeping with the lack of dithiolene character noted for this complex. A review has been written on structural studies of iron-sulphur proteins.341 An investigation of thioether-halogen complexes of rhodium and iridium finds the Rh' complexes unstable and polymeric but both fac- and mer-isomers of [Rh"'Cl,(PhSR),] (R = Me Et Pr or Bu) were isolated.342 Both Ir' and Ir"' have a low affinity for sulphides.A meridional configuration has been found for [MCI,(SEt,),] (M = Ir"' Rh'" or R u " ' ) . ~ ~ ~ An attempted preparation of (SacSac),Ru (SacSac = dithioacetylacetonate) from RuCl produced the novel complex (Sa~Sac),RuCl(N0),~~~ which has a trans-configuration. Contamination of the commercial RuC1 by NO was found to be responsible and the same complex was made from RuCl,(NO),H,O. D.c. polarographic studies on these SacSac derivatives and on [M(SacSac),] (M = Co, Ni Pd or Pt) and [M(SacSac),] (M = Co or Ir) established that these derivatives 3 3 7 G . Tauzher G. Mestroni A. Puxeddu R. Costanzo and G. Costa J . Chem. SOC. ( A ) , 3 3 8 A. Davison and E. S. Switkes Inorg. Chem. 1971 10 837. 3 3 9 M. R. Churchill J.Cooke J . P. Fennessey and J. Wormald Inorg. Chem. 1971 10, 3 4 0 G. P. Khare A. J. Schultz and R. Eisenberg J . Amer. Chem. SOC. 1971,93 3597. 3 4 1 J. C. M. Tsibris and R. W. Woody Co-ordination Chem. Rev. 1970 5 417. 3 4 2 J. Chatt G. J . Leigh A. P. Storace D. A. Squire and B. J. Starkey J . Chem. SOC. ( A ) , 3 4 3 E. A. Allen N. P. Johnson and W. Wilkinson Chem. Comm. 1971 804. 3 4 4 G. A. Heath and R. L. Martin Austral. J . Chem. 1970 23 2297. 197 1,2504. . 1031. 1971,899 414 R. J. Cross and J . M. Winjield can accept one or more electrons stepwise and reversibly. The reduction poten-tials suggest that SacSac complexes of metals in unusually low oxidation states might be stable.345 The X-ray crystal structures of the bis-NN-diethyldiselenocarbamates of Ni" Cu" and Zn" have been compared with those of their sulphur analogues.M-Se is ca. 11.3 pm longer than M-S and C-Se is ca. 15.2 pm longer than C-S. This suggests that the M-Se bond order is higher than th&af M-S.346 Tristriphenylphosphinechlororhodium(1) reacts with white phosphorus in ether or methylene chloride at 195K to produce the P complex (Ph3P),-Rh(P,)C1.347 The reaction also proceeds when the Ph3P groups are replaced by (p-tol),P (m-tol),P or Ph,As. The complexes formed are air-sensitive and mono-meric and the P4+ fragment appears in their mass spectra. P4 is displaced by CO Et3P or diphos. The structure ofthe adduct is not yet known but symmetrical facial-bonding (24) is suspected. The series of complexes M(biL),X (M = Pd" Rh PPh, Ph,P' I 'C1 (24) or Pt"; biL = 1,8-naphthalenebis(dimethylarsine); X = C1 Br I SCN ClO, or NO3) has been isolated.348 Five-co-ordinate square-pyramidal compounds appear to be present when X is halogen or SCN but X = ClO or NO3 gives the more usual square-planar configuration.The reactions of cyanogen with several transition-metal complexes have been examined.349 It reacts only with low-oxidation-state derivatives adding two cyanide groups by an oxidative addition mechanism. Thus for example bis-(triphenylphosphine)dicyanoplatinum(II) was produced from cyanogen and tetrakis( triphenylphosphine)platinum(O). I4N.m.r. chemical shifts of cyanide and isocyanide complexes have been com-pared with v(CN) to estimate the amount of 7c ba~k-bonding.~~' This appears to be very small except when isocyanide is the only ligand attached to low-oxidation-state metals.Competing Ir-acceptors such as CO reduce the back-bonding to isocyanide. Reactions of Co-ordinated Ligands.-The subject of metal-ion control in the synthesis of Schiff-base complexes has been reviewed. Examples include in situ ligand preparations rearrangements oxidations and exchange reaction^.^ 345 A. M. Bond G. A. Heath and R. L. Martin Znorg. Chem. 1971 10,2026. 3 4 6 M. Bonamico and G. Dessy J. Chem. SOC. ( A ) 1971 264. 3 4 7 A. P. Ginsberg and W. E. Lindell J. Amer. Chem. SOC. 1971,93 2082. 3 4 8 R. Ros and E. Tondello J. Inorg. Nuclear Chern. 1971 33 245. 349 3 5 0 W. Becker W. Beck and R. Rieck Z. Naturjorsch. 1970 25b 1332. 3 5 1 M . Bressan G. Favero B.Corain and A. Turco Znorg. Nuclear Chem. Letters 1971,7, 203. L. F. Lindoy Quart. Rev. 1971 25 379 The Transition Elements 41 5 When molecular oxygen is bubbled through solutions of [Ru(NH,)~]~ + con-taining S2032 - or SPO, - the sulphamate complex [Ru(NH,),(NHSO,)] + is formed in good yield.352 Comparison with the known cobalt(m) derivative confirms Ru-N bonding. The sulphamate is probably produced by transfer of a sulphur atom to co-ordinated amide (NH2-) with subsequent oxidation by 0,. Information on the nature of the interaction between co-ordinated ammonia and outer-sphere groups has also been obtained by observing v(XFY) in [Ru(NH,),-(XY)I2' (XU = N, CO MeCN CF,CN PhCN Bu'CN or MeNC).353 The stretching frequency rises with increasing counter-ion size in the solid phase.v(NFN) in [(NH3)5RuN-NRu(NH3),]4+ falls in the same way. Both the observed trends can be explained in terms of the counter-ion interaction with NH,. The methylamine (L) complex ion [RuL6I2+ (isolated as I- Br- or BF,-salts) is much more prone to oxidation than the analogous ammonia complex. O2 reacts with the complex at ambient temperatures to produce co-ordinated cyanide The BH,CN- ion (L) forms N-bonded complexes with ruthenium.355 Both [(NH,),RuL]+ and [(NH3)5R~L]2+ are moderately stable in water but acidic hydrolysis of the former produces N -bonded [(NH,),RU(NCH)]~+ Several reactions of nickel(I1) tetradehydrocorrin complexes have been de-scribed this year. 1,19-Dimethylcorrin-nickel(11) perchlorate (25) is obtained from the room-temperature hydrogenation (Raney nickel 25 atm) of the corresponding tetradehydrocorrin c~mplex.~ 56 8,12-Diethyl-l,2,3,7,13,17,18,19-octamethylcor-rin-nickel(I1) nitrate is readily converted by base (or polar solvent) in air to the neutral 0x0-compound (26).5 7 Reductive methylation of decamethyltetrade-hydrocorrin-nickel(I1) iodide (27) by sodium anthracenide and methyl iodide methylates the 10-position and opens the ring at 1-19 to give (28).358 Oxidation closes the ring to yield (29) and the process can be repeated to produce (30). The acid-permanganate oxidation of ( - )-[(salicylato)(en),Co] + (3 1) to ( -)-[(oxalato)(en),Co] + (32) has been followed by the l4C-labe1ling of specific points in the ring. Complete loss of C(7) is observed along with almost complete re-tention of C(2).The other carbon atom in the product is derived to the extent of ca. 50% from C(l) and 50% from C(3).359 The octahedral complex dichlorobis-(diphenyl-o-methylselenidophenylphosphine)nickel(II) is known to demethylate easily on refluxing in dimethylformamide. The X-ray crystal structure of the product confirms its identity as trans-bis(dipheny1-o-selenolatopheny1phosphine)-nicke1(11).~~~ Nitric oxide reacts with bis(pentane-2,4-dionato)palladium(11) to 3 5 2 J. N . Armor and H. Taube Inorg. Chem. 1971 10 1570. 3 5 3 J. Chatt G . J. Leigh and N. Thankarajam J . Chem. SOC. ( A ) 1971 3168. 3 s 4 W. R. McWhinnie J. D. Miller J . B. Watts and D. Y . Waddan Chem. Comm. 1971, 3 5 s 356 A. W. Johnson and W. R. Overend Chem. Comm. 1971 710. 3 5 7 A.Hamilton and A. W. Johnson Chem. Comm. 1971 523. 3 5 8 H. H. Inhoffen J. W. Buchler L. Puppe and K . Rohbock Annulen. 1971 747 133. 3s9 A. G . Beaumont R. D. Gillard and J. R. Lyons J . Chem. Soc. ( A ) 1971 1361. 3 h 0 R. Curran J. A. Cunningham and R. Eisenberg Inorg. Chem. 1970,9,2749. 629. P. C . Ford Chem. Comm. 1971 7 416 R. J . Cross and J . M. Winjield Me 0 Me Me Me Me Me Me Me (29) + P-0 produce a mixture of 3-hydroxyiminopentane-2,4-dionato(pentane-2,4-dionato)-palladium(I1) and bis-(3-hydroxyiminopentane-2,4-dionato)palladium(11).~ Cobalt(1r) sulphite and nickel(@ sulphite are oxidized by SO2 and DMSO (but not by either alone) to ionic pyrosulphates [M(DMSO),]S,O .362 The reaction, 3 6 1 362 R. Maylor J. B. Gill and D. C. Goodall Chem. Comm. 1971 671 D. A. White J . Chem. SOC. (A) 1971 233 The Transition Elements 417 which proceeds only for covalently bonded sulphites is believed to proceed via co-ordination of SO2 to give a pyrosulphite. The structure 02S-0-S022- is preferred for this intermediate rather than 03S-S022-. The pyrosulphite is then oxidized by DMSO to pyrosulphate gifing Me2S as by-product

ISSN:0069-3022    

DOI:10.1039/GR9716800365

出版商:RSC    

年代:1971

数据来源: RSC

摘要:

15 Transition-metal Carbonyl, Organometallic and Related Complexes By P. S. BRATERMAN Department of Chemistry The University Glasgow G I 2 800 To the existing detailed surveys'.' that overlap this Report another is about to be added.3 The rate of growth of knowledge in the areas covered continues to increase as does the interest in mechanistic and comparative studies. Thus not only the selection of papers but to some extent their classification is bound to be subjective. Reviews have appeared on the organometallic chemistry of the lanthanides and actinide^,^ lower oxidation states of t i t a n i ~ m ~ and platinum(I1) with Group IV;6 on models for Vitamin B12;' on the optical activity of asymmetric tran-sition-metal atoms in organometallic complexess and the n.m.r. spectra of fluxional organometallics ;9 on oxidative addition to transition-metal com-plexes," ligand effects in transition-metal catalysis,' ' organometallics as poly-merization catalysts in generali2 and in the production of ordered r ~ b b e r s ' ~ and on homogeneous catalysis by ruthenium.l4 Preparative routes to starting materials for organometallic compounds of palladium and platin~m,'~ and to a range of organometallics including species of type (n-C,H,)Fe(CO),L and to compounds with transition-metal-Group IV metal bonds,I6 have been reviewed. Organometallic Chem. Rev. ed. D. Seyferth and R. B. King 1972. ' 'Spectroscopic Properties of Inorganic and Organometallic Compounds,' ed. N. N. Greenwood (Specialist Periodical Reports) The Chemical Society London 1972, VOl.5 . 'Organometallic Chemistry,' ed. E. W. Abel and F. G. A. Stone (Specialist Periodical Reports) The Chemical Society London 1972 Vol. 1. H. Gysling and M. Tsutsui Adv. Organometallic Chem. 1970 9 361. R. S. P. Coutts and P. C. Wailes Adv. Organometallic Chem. 1970 9 136. 1970 4 7. and G. Tauzher Inorg. Chirn. Acta Rev. 1970,441. H. Brunner Angew. Chem. Internat. Edn. 1971 10 249. K. Vrieze and P. W. N. M. van Leeuwen Progr. Inorg. Chem. 1971 14 1. G. Henrici-Olive and S. Olive Angew. Chem. Internat. Edn. 1971 10 105. A. Gumboldt Fortschr. Chem. Forsch. 1971 16 299. ' U. Belluco G. Deganello R. Pietropaolo and P. Uguagliati lnorg. Chim. Acra Rev., ' A. Bigotto G Costa G. Mestroni G. Pelliger A. Puxeddu E. Reisenhofer L. Stefani, l o J. Halpern Accounts Chem.Res. 1970 3 386. l 3 H. Weber Fortschr. Chem. Forsch. 1971 16 329. ' 4 B. R. James Inorg. Chim. Acta Rev. 1970 4 73. l 5 F. R. Hartley Organometallic Chem. Rev. 1970 A6 119. l 6 R. W. Parry Inorg. Syntheses 1970 12 35 420 P. S. Braterman Of general interest is the use of n.m.r. shift reagents in organometallic chemis-try not only as spectroscopic tools but as detectors of ‘hard’ Lewis base charac-ter.I7 1 Metal Carbonyls The synthesis and reactivity of metal carbonyls has been reviewed,Is as has the synthetic use of metal carbonyl anions.” Bonding in metal carbonyls in general has been discussed qualitative arguments being presented for the ‘straight bond’ model of CO,(CO)~ and for a closed-shell description of the 86-electron system in hexanuclear metal carbonyls.20 Mono- and Di-nuclear Carbony1s.-SCF-MO calculations on nickel carbonyl give the correct energy ordering ( t 2 > e) for the highest filled orbitals and show a decrease on co-ordination in carbon 2s and increase in carbon 2 p populations, and a greater contribution of 4p than of 3d to metal-carbon overlap;21 the agree-ment on these points with naive chemical intuition20 is reassuring.Calculations on MII(CO)~+ Mn(CO)’CN Mn(CN),C04- and Mn(CN),’ - show variations in both 6- and n-bonding between cyanide and metal while changes in the metal-CO bond are largely confined to the 7t-system.22 Less rigorous calculations on Mn2(CO)lo reveal a significant interaction between each metal atom and the CO groups bonded axially to the other but this is not so for Re2(CO)lo.23 X-Ray photoelectron spectra of carbonyls show a shift of 0 1s and more especially of C 1s to low bonding energies relative to carbon monoxide providing direct evidence for the importance of n-ba~k-bonding.~~,~’ (By contrast the carbon atoms of n-cyclopentadienyl rings are more positive than those in hydro-carbon~,~’ especially when such charge-withdrawing ligands as CO are present.’ b, It has been shown that in symmetrical carbonyls at least carbonyl stretching parameters [calculated from v(C-0) data only] approximate very closely to the true quadratic force constants of the M-C-0 grouping as a whole [though not to the true force constant for C-0 stretching at constant metal-carbon distance ; this distinction is responsible for the anomalous similarity between the effects of I3CO and of C ” 0 substitution in COCI,(CO)(PE~,),].~~*~~ In a fundamental theoretical study the importance of electronic relaxation effects has been em-phasized ; since these can be related to specific electronic transitions comparisons l 7 T.J . Marks J. S. Kristoff A. Alich and D. F. Shriver J . Organometallic Chem., l 8 E. W. Abel and F. G. A. Stone Quart. Rev. 1970 24 498. l9 R. B. King Accounts Chem. Res. 1970 3,417. 2 o P. S. Braterman Structure andBonding 1971 10 57. 2 1 I. H. Hillier and V. R. Saunders Chem. Comm. 1971,642. 2 2 R. L. DeKock A. C. Sarapu and R. F. Fenske Znorg. Chem. 1971 10 38. 23 D. A. Brown W. J. Chambers N. J. Fitzpatrick and R. M. Rawlinson J . Chem. 2 4 M. Barber J. A. Connor I. H. Hillier and V.R. Saunders Chem. Comm. 1971 682. 2 5 (a) D. T. Clark and D. B. Adams Chem. Phys. Letters 1971,10 121; (b) D. T. Clark 2 6 J. R. Miller J . Chem. SOC. ( A ) 1971 1885. 1971 33 C35. SOC. ( A ) 1971 720. and D. B. Adams Chem. Comm. 1971 740. G. Bor B. F. G. Johnson J. Lewis and P. W. Robinson J . Chem. SOC. ( A ) 1971,696 Transition-metal Carbonyl Organometallic and Related Complexes 42 1 even between closely similar species can be dangerous.28 It has also been shown that the ordering of n-bonding parameters derived from carbonyl stretching frequencies is sensitive to the precise recipe used for their c a l ~ u l a t i o n ~ ~ and in a detailed intensity study of the i.r. spectra of Cl,SiCo(CO), Ph,SiCo(CO),, and Ph,PFe(CO) that the apparent angle between CO groups is a critical func-tion of the dipole moment change difference between modes of different sym-metry.,' The Raman and i.r.spectra of Re(CO),Cl and Re(CO),Br have been assigned,,' as has the Raman spectrum of liquid Mo(CO) . 3 2 The photochemical generation in matrices from the hexacarbonyls of species V(CO),(MeTHF)- Cr(CO),(MeTHF) and the molybdenum and tungsten ana-logues has been reported as has the photochemical regeneration of V(CO) - . 3 3 The species M(CO) (M = Cr Mo or W) generated photochemically in argon matrices have been described in detail., It is agreed that the photoreversal of photolysis takes place by a trivial process of lattice softening permitting recom-bination of The photolysis of matrix-isolated Fe2(C0)9 is a complex process ; there is spectroscopic evidence for initial formation of a doubly carbonyl-bridged species Fe,(CO) which may be converted into a more stable non-bridged form.3 Flash photolysis studies in hexane at room temperature have demonstrated that the species of constitution Cr(CO) initially produced is inert to carbon monoxide and to hydrogen but decays with a half-life of 6 ps to a more stable species; this can recombine with C036a and activates the 1,4-addition of hydrogen to conjugated diene~.,~' Long-wavelength emission has been detected at low temperatures from a variety of species of type W(CO)5L [including W(CO) itselfJ in hydrocarbon matrices.37 The matrix deposition of metal atoms along with carbon monoxide has been used to generate all the species Ni(CO) (n = 1-4) and at least five different tantalum carbonyl specie^,^' as well as copper- and silver-containing species each of which seems to have two i.r.-active carbonyl stretching modes.39 The chemical shift of I3C in chromium carbonyls in natural abundance has been observed to be sensitive to environment ; cis- and trans-CO groups may be distinguished.The carbene carbon of Cr(CO),C(Me)OMe appears to be electron-deficient. While the methyl groups of CSH,Fe(C0)2Me and C,H,W(CO),Me 2 8 J. K. Burdett J . Chem. SOC. ( A ) 1971 1195. 2 9 F. T. Delbeke E. G. Claeys and G. P. van der Kelen J . Organometallic Chem. 1971, 30 D. J. Darensbourg Znorg. Chim. Acra 1970,4 597. 3 1 3 2 R . Pince and R. Poilblanc Compt. rend. 1971,272 C 83. 3 3 ( a ) P. S. Braterman and A. Fullarton J .Organometaffic Chem. 1971 31 C27; (6) 3 4 M. A. Graham M. Poliakoff and J. J. Turner J . Chem. SOC. ( A ) 1971,2939. 3s M. Poliakoff and J. J. Turner J . Chem. SOC. ( A ) 1971 2403. 3 6 (a) J. Nasielski P. Kirsch and L. Wilputte-Steinert J . Organometallic Chem. 1971, 29 269; (b) ibid. 1971 27 C13. 3 7 M. Wrighton G. S. Hammond and H. B. Gray J . Amer. Chem. SOC. 1971,93,4336. 3 8 R . L. DeKock Znorg. Chem. 1971 10 1205. 3 9 J. S. Ogden Chem. Comm. 1971,978. 28 391. W. A. McAllister and A. L. Marston Spectrochim. Acta 1971 27A 523. M. J . Boylan P. S. Braterman and A. Fullarton ibid. p. C29 422 P . S . Braterman resonate to high field of tetramethylsilane the phenyl ring carbons of (C5H5)2-TiPh occur to low field of toluene; this effect is attributed to a reduction of ring excitation energies leading to an increased paramagnetic c o n t r i b ~ t i o n .~ ~ Polynuclear ions due to ion-molecule reactions have been observed in the mass spectra of the Group VI h e x a c a r b o n y l ~ ~ ' ~ ~ ~ and other organochromium com-p l e x e ~ . ~ ~ Careful scrutiny of ionization efficiency data for production of fragments M(CO),,+ from the hexacarbonyls reveals 'simultaneous' loss of three two or one CO from both parent and daughter ions.43 In Cr,(C0)102- and MO,(CO),~~ - crystallographic studies show that the carbonyl groups are staggered whereas in Cr2(CO),,H- (which contains a linear hydrogen bridge) they are eclipsed. In the dianions there is appreciable obtuseness (93-94 ") in the C,,-metal-C, bond while the corresponding angle in the bridged hydride is only 91 0.44 (This suggests that the obtuseness may be due to interaction with the other metal atom as discussed above.23) The Cr2(CO)loI- anion however is bent with a metal-iodine-metal angle of 118°.45 The anion W,(OH),(CO);- has been shown to have the structure (OC),W(OH),W(CO),3- with three p-hydroxy-bridges.Despite the absence of a formal bond the metal-metal distance is almost identical with that in [ c s H J w(co)3 1 2 .46 Photochemical exchange of 13C0 for l2CO in MO(CO)~NHC~H, occurs preferentially at equatorial sites. The position of the label (which may be found from the i.r. spectrum) becomes randomized during the conversion by a dis-sociative mechanism of this complex into Mo(CO),AsPh . Thus there is axial-equatorial interchange in the intermediate MO(CO)~ f~agment.~' The electrochemical one-electron oxidation of a range of chromium carbonyls has been observed ; n-accepting ligands make this oxidation more difficult.48 The anions c~s-M(CO)~(CNO)~~- (M = Cr Mo or W) have been prepared phot~chemically.~~ An X-ray structural investigation of Mn(CO),Cl indicates strongly (though the authors urge caution) that the metal-carbon bond trans to C1 is about 9pm shorter than those trans to CO." The reaction of Ph,GeMn(CO) with phos-phines in decalin proceeds by competing SN1 and S,2 pathways to give trans-Ph,GeMn(C0)4PR ; since the SN1 reaction with bipyridyl which is sterically less hindered gives a cis-product it appears that initial loss of a carbonyl cis 40 L.F.Farnell E. W. Randall and E. Rosenberg Chem. Comm. 1971 1078. 4 1 C. S. Kraihanzel J. J. Conville and J. E. Sturm Chem. Comm. 1971 159. 42 J. Muller and K. Fenderl Chem. Ber. 1971 104 2199. 43 G. D. Flesch and H. J. Svec J . Chem. Phys. 1971 55 4310. 44 L. B. Handy J. K. Ruff and L. F. Dahl J . Amer. Chem. SOC. 1970,92,7312. 4 5 L. B. Handy J. K. Ruff and L. F. Dahl J . Amer. Chem. SOC. 1970,92,7327. 46 V. G. Albano G. Ciani and M. Manassero J . Organometallic Chem. 1970 25 C55. 47 D. J. Darensbourg M. Y . Darensbourg and R. J. Dennenberg J . Amer. Chem. SOC., 4 8 J. A. McCleverty D. G. Orchard J. A. Connor E. M. Jones J. P. Lloyd and P. D. 4 9 W. Beck P. Swoboda K. Feldl and E. Schuierer Chem. Ber. 1970 103 3591. 5 0 P. T. Greene and R. F. Bryan J . Chem. SOC.( A ) 1971 1559. 1971,93,2807. Rose J . Organometallic Chem. 1971 30 C75 Transition-metal Carbonyl Organometallic and Related Complexes 423 to germanium is followed for bulky entering groups by a rearrangement to place the vacant site in the trans po~ition.~' The broad-line Mn and halogen n.m.r. spectra of pentacarbonylmanganese halides suggest that calculations5 are correct in placing the halide pn electrons at highest energy but exaggerate the degree of metal-halogen a - b ~ n d i n g . ~ ~ Quantitative studies show that di-iron enneacarbonyl reacts with phosphines in hydrocarbons by two routes ; of these one generates equal amounts of Fe(CO), and Fe(CO),L [via presumably Fe(CO),] whereas the other gives disubstituted products directly.54 Several new compounds containing the Fe,(CO) unit have been reported.Thus Ph,C C NMeFe,(CO) has been shown crystallographically to have the structure (l)? Reaction of pentacarbonyliron with lithium diethylamide, followed by oxidation with triphenylmethyl chloride gives (2).56 Thiobenzo-phenone reacts with Fe,(C0)9 at room temperature to give a product formulated Ph I (4) Fe(CO), (3) H R 1x1 (OC),Fe -Fe(CO), as (3).57 Whereas the ligand (4) has been converted into a product of composition (ligand)Fe,(CO) which contains a bridging ~ a r b o n y l ~ ~ ( 5 ) reacts photo-chemically with Fe(CO) to give (6).59 The reaction of metal vinyl derivatives with Fe,(C0)9 gives rise to a range of interesting products. Thus compounds C5H5Fe(C0)2CH CHR give products (7) whereas C5H5W(C0)3CH CH-CO-Ph gives rise to (8)-(10).MeCOCH CHRe(CO) simply co-ordinates as 5 1 G . R. Dobson and E. P. Ross Znorg. Chim. Acta 1971 5 199. 5 2 R. F. Fenske and R. L. DeKock Znorg. Chem. 1970,9,'1056. 53 H. W. Spiess and R. K. Sheline J . Chem. Phys. 1971,54 1099. 5 4 P. S. Braterman and W. J. Wallace J . Organometallic Chem. 1971 30 C17. 5 5 K. Ogawa A. Torii H. Kobayashi-Tamura T. Watanabe T. Yoshida and S. Otsuka, 5 6 E. 0. Fischer and V. Keiner J. Organometallic Chem. 1971 27 C56. " H. Alper and A. S. K. Chan Chem. Comm. 1971 1203. 5 8 H. tom Dieck I. W. Renk and H.-P. Brehm Z . anorg. Chem. 1970,379 169. 5 9 H. Kisch J . Organometallic Chem. 1971,30 C25. Chem. Comm. 1971,991 424 P. S. Braterman an olefin to a tetracarbonyliron fragment. So does C,H,Fe(CO),COCH :-CHPh but the product (11) may be converted photochemically into (12) or by warming to (7; R = Ph).60 RCH=CH.Fe(CO) (n-C H,) PhCO.CH=CH* W( C0)2(n-C5 H ,) 1 / 1 .1 / I (7) (8) Fe(CO) Fe(CO), (9) (10) (OC),Fe-CO (OC),Fe-CO PhCO.CH=CH.W(CO),(n-C H5) PhCCH=W(CO),(n-CS H5) 1 8 4 PhCH=CH.CO.Fe(CO),(n-C,H,) PhCH=CHC.Fe(C0)2(n-C,H,) 1 I1 (OC),FeJO 1 Fe(CO), (1 1) (12) The broad-line 59C0 n.m.r.spectrum of dicobalt octacarbonyl shows the principal axis of the field gradient tensor to point fairly closely towards the vacant bridging site ; this is interpreted as evidence against the 'bent bond' model.61 The disproportionation rate of CO(CN),~- in the presence of CO to give CO(CN)63 - Co(CN),(CO),' - and free cyanide,62 is proportional to [CO(CN),~ -]'[CO] [CNI- '.Dicobalt octacarbonyl reacts with bis(pentafluor0-pheny1)disulphide to give a product formulated as (13) ; the pentachlorophenyl analogue is less stable.63 C F l 6 C6F5 (13) DMF has been used as a carbonylating agent in the preparation of a range of substituted carbonyls of rhodium and platinum.64 The crystal structure of the tetrabutylammonium salt of ci~-Cl,Rh(C0)~- has been determined ; the short rhodium+arbon distance of 172 pm is attributed to n-b~nding.~' The carbonyl iodides of Rh"' and Ir'" catalyse the decomposition of formic acid. Reduced 6 o A. N. Nesmeyanov M. I. Rybinskaya L. V. Rybin V. S. Kaganovich and P. V. 6' E. S. Mooberry M. Pupp J. L. Slater and R. K. Sheline J . Chem. Phys. 1971 55, 6 2 J. Halpern and M.Pribanic J . Amer. Chem. SOC. 1971 93 96. 6 3 G. Bor and G. Natile J . Organometallic Chem. 1971 26 C33. 64 ( a ) Yu. S . Varshavskii T. G. Cherkasova N. A. Buzina N. N. Knyazeva and T. I. Ionina Russ. J . Inorg. Chem. 1970 15 1187; (b) Yu. S. Varshavskii N. V. Kiseleva, T. G. Cherkasova and N. A. Buzina J . Organometallic Chem. 1971 31 119. Petrovskii J. Organometallic Chem. 1971,31 257. 3655. 6 5 C. K. Thomas and J. A. Stanko Znorg. Chem. 1971,10 566 Transition-metal Carbonyl Organometallic and Related Complexes 425 products are obtained only at low acid concentrations and a probable mechanism is of the type66 M(CO),I,- + HCOOH + M(CO),I,- + 2HI + CO, M(CO),I,- +2HI -+ M(CO),I,- + H, The species Cu(en)CO+Cl- has been characterized ; the carbonyl stretching frequency is 2080 cm- '.A second species absorbing at 1905 cm-' is formulated as a bridged complex [(enC~),(C0),]~ f.67 Polynuclear Carbony1s.-The reaction of tri-iron dodecacarbonyl with di-(t-buty1)acetylene takes place with cleavage of the Fe grouping to give the product (14) in which the (formally double) iron-iron bond has a length of 221 pm.68 Bu' - . (OC) Fe .= Fe(CO), B u' (14) The reaction of iron pentacarbonyl with [Mn(CO),]- gives a variety of products including [MnFe,(CO) ,] - decomposition of which gives the novel anion [Fe6(C0),,Cl2- for which the structure (15) has been determined.69 (It is oc /v\ (15) (16a) M = Ru(CO), noteworthy that this is an 86-electron system.) Acidification gives Fe,(CO),,C.70 A product RU,(CO)~C~~H, a probable precursor of the known Ru,(CO),CloH,, has been isolated from the reaction of azulene with RU,(CO)~, and the structure (16a) determined.' Bis(to1ane)triosmium octacarbonyl (tolane = diphenyl-acetylene) reacts with carbon monoxide by a second-order mechanism to give a " '-" K. Nicholas L. S. Bray R. E. Davis and R. Pettit Chem. Comm. 1971 608. 69 M. R. Churchill J. Wormald J. Knight and M. J. Mays J. Amer. Chem. SOC. 1971, 93 3073. ' O R. P. Stewart U. Anders and W. A. G. Graham J. Organometallic Chem. 1971, 32 C49. " M. R. Churchill F. R. Scholer and J. Wormald J. Organometallic Chem. 1971, 28. C21. D. Forster and G. R. Beck Chem. Cnmm. 1971 1072. G. Rucci C. Zanzoterra M. P. Lachi and M. Camia Chem. Comm. 1971,652 426 P . S . Braterman product (P~C,P~),OS,(CO)~ for which the structure (16b) is ~uggested.~ An intermediate of composition OS,O,(CO),~ has been isolated from the reaction of osmium tetroxide with CO [the standard Os,(CO), synthesis]; there is no bridging carbonyl freq~ency.~, Ph P h v r 0 ) 3 (OC),OS -Os(CO), (1 6b) The reaction of Co,(CO),CH with such carbene precursors as Hg(CH,I), gives Co,(CO),CMe ; however the dichlorocarbene precursor PhHgCC1,Br gives CO,(CO),CP~.~~ Compounds Co,(CO),CY (Y = F Me or Ph) react with arenes to give species Co,(CO),CY(arene).Acetylene complexes (YC i CY)Co,(CO), are formed as by-products; it is suggested that the Y,C, unit is derived from the starting cl~ster.~’ The crystal structure of PhCCo,(CO),-(n-me~itylene)~~ confirms the assignment from spectroscopic e~idence,~ ’ of a structure (n-areneCo) [Co(CO),],CPh ; however the cyclo-octatetraene deriva-tive Co,(CO),C,H&Ph has the structure (17).In [co,(co),C] the central (17) M = Co(CO), carbon-carbon bond length is 137 pm; this extreme shortness is attributed to the unusual hybridization imposed on carbon by the geometry of the C0,C tetra-h e d r ~ n . ’ ~ Mono- di- and tri-substituted derivatives of Co,(CO),CY with phosphines and arsines have been prepared. The compounds of type Co,(CO),-LCMe generally contain bridging CO groups (the triphenylphosphine derivative is an exception) as do di- and tri-substituted derivatives. Bridged-non-bridged and in one case [CO,(CO),PCX,CPh Cx = cyclohexyl] axial-equatorial iso-merism have been ~bserved.’~ 7 2 0.Gambino G. A. Vaglio R. P. Ferrari and G. Cetini J . Organometallic Chem., 7 3 C. W. Bradford and R. S. Nyholm J . Chem. SOC. ( A ) 1971,2038. 7 4 D. Seyferth R. J. Spohn and J. E. Hallgren J . Organometallic Chem. 1971 28 C34. 7 5 B. H. Robinson and J. L. Spencer J . Chem. SOC. ( A ) 1971 2045. 7 6 M. D . Brice R. J. Dellaca B. R. Penfold and J. L. Spencer Chem. Comm. 1971 72. 7 7 T. W. Matheson B. H. Robinson and W. S. Tham J . Chem. SOC. ( A ) 1971 1457. 1971 30 381 Transition-metal Carbonyl Organometallic and Related Complexes 427 Products of composition R,SiCo,(CO),, from the reaction of R2SiH2 and dicobalt octacarbonyl are formulated as CO,(CO)~C~O~SIR,-CO(CO)~ . 7 8 Novel species (arene)Co,(CO) formulated on i.r. evidence as (18) result from the Arene c o (18) M = Co(CO), reaction of cobalt carbonyls or dicobalt hexacarbonyl-acetylene-norbornadiene mixtures with arene solvents; interestingly the latter mixtures in inert solvents give (~-C,H,)CO(CO),.~~ [CO(CO)~],S~~ has been prepared by the reduction of cobalt acetate-antimony trichloride mixtures with carbon monoxide and hydro-gen in methanol and shown crystallographically to have a structure in which each face of a tetrahedron of CO(CO)~ units is bridged by an antimony atom.80 [C,H,NiCO] is the precursor of a new family of mixed cluster carbonyls, reacting with dicobalt octacarbonyl to give C,H,N~CO~(CO)~ (19) and with Fe,(C0)9 and Mn(CO),- to give (CSH,),Ni,M(CO) (M = Feo or Mn-’) (20a and b).81 ( 7 G H ) 0 \ Ni (n-C,H5)Ni-\-7Ni(n-C,H 5 ) C (20) (a) M = Fe(CO), YM/ M- L\AM P M ’ I c’ ‘c 0 0 0 (19) M = Co(CO) (b) M = Mn(C0); The reaction of Ni(CO) with Cr,(CO),02- or the related molybdenum or tungsten species produces complexes Ni,(C0)6[M(C0)5]22 - ; the structure (21) hjf(C0)S o c f l y 7 0 I OCNi NiCO \cl/ 01 i4 (CO), (21) M = Moor W 7 8 S.A. Fieldhouse A. J. Cleland B. H. Freeland C. D. M. Mann and R. J. O’Brien, 7 9 I. U. Khand G. R. Knox P. L. Pauson and W. E. Watts Chem. Comm. 1971 36. J . Chem. SOC. ( A ) 1971,2536. A. S. Foust and L. F. Dahl J . Amer. Chem. SOC. 1970,92 7337. A. T. T. Hsieh and J. Knight J . Organometallic Chem. 1971 26 125 428 P. S . Braterman has been determined for two of these and the third (M = Cr) is isomorphous. The nickel-nickel distance (234 pm) is normal for a single bond while the nickel-M distances for M = Mo or W are anomalously long (310pm).These results have been rationalized by a scheme in which the M(CO) groups form electron-pair bonds with the Ni triangle.82 Insertion reactions of zeropositive platinum into metal-metal bonds give a variety of novel compounds. Thus di-iron ennea-carbonyl gives (22) and (23) Ru,(CO), gives (24a) and (25a) and H,Os(CO), gives (24b) and (25b).83 L Fe(CO) L Fe(CO)4 OC-M (CO) L OC-Pt ’ oC-Pt, L,Pt/ I ‘Pt/ 1 LFjt/ 1 \co L ( O q 2 h / I \ 1 / \co I \ / C-M(C0)2L L (25) (a) M = Ru (b) M = 0 s Carbonyl Hydrides-The attachment of hydrogen to a metal atom renders motion of that atom highly active in inelastic neutron scattering. This technique has been applied to polynuclear carbonyl hydrides providing evidence for the view that in HFeCo,(CO), the proton is inside the metal atom cage and that in H,Mn,(CO), and the rhenium analogue the metal-metal force constants are about half what they are in Mn,(CO), and Re,(C0),,.84 The use of a hydro-carbon solvent facilitates the hydrogenation of metal carbonyls even under relatively mild conditions (36@-440K 1 atm); produced in this way are may be converted into H,Ru,(CO),~ whereas H,FeRu,(CO), gives the unstable H,F~Ru,(CO),,.~~ The acidification of metal carbonyl anions promises to be a technique of considerable synthetic importance (compare also ref.70). Thus reaction of Mn(CO),- with Os,(CO),, followed by acidification gives not only the expected species MnOs,(CO),,- and HMnOs,(CO), but also HMnOs,-(CO), and H,MnOs,(CO), .Re(CO),- behaves similarly and in addition gives rise to HReOs,(CO) 5.86 Warming in concentrated sulphuric acid followed by precipitation with water converts HRu,(CO),,SEt into H,Ru,(CO),S, for which a tetrahedral Ru,S skeleton is suggested.*’ Carbonyl Nitrosy1s.-The reaction rates of the complex [Re(CO),(NO)Cl,], with such ligands as substituted pyridines have been studied; the reaction is first order in both reagents.88 Ally1 dicarbonylnitrosyliron and substituted derivatives may be reduced either polarographically (by a 2-electron process in OC’ \Fe(CO), \ Fe(CO)4 (22) (23) (24) (a) M = Ru (b) M = 0 s H,Re,(C0)12 7 H4Re4(C0)12 9 H4Ru4(CO)12 9 and H40s4(CO)12 * H,Ru4(CO)13 e 2 J. K. Ruff R.P. White jun. and L. F. Dahl J . Amer. Chem. SOC. 1971 93 2159. 83 M. I. Bruce G. Shaw and F. G . A. Stone Chem. Comm. 1971 1288. 8 4 J. W. White and C. J. Wright J . Chem. SOC. (A) 1971 2843. 8 5 H. D . Kaesz S. A. R. Knox J. W. Koepke and R. B. Saillant Chem. Comm. 1971,477. 8 6 J. Knight and M. J. Mays Chem. Comm. 1971 62. 8 7 A. J. Deeming R. Ettore B. F. G. Johnson and J. Lewis J . Chem. SOC. (A) 1971, 8 8 F. Zingales A. Trovati and P. Uguagliati Znorg. Chem. 1971 10 510. 1797 2701 Transition-metal Carbonyl Organometallic and Related Complexes 429 acetonitrile) or chemically (by borohydride) ; it is suggested that the initial products are [Fe(CO),NO]- and C,H,- which give rise to the observed products [Fe(CO),NO- CO Fe2+ and propene] by reaction with solvent or starting material.The half-wave potential is more sensitive to substituents at C-1 of the n-ally1 grouping than at C-2.89 The reaction of ally1 dicarbonyl-nitrosyliron with phosphines proceeds by an SN2 mechanism to give carbonyl substitution products. Steric factors influence the reaction rates of different pho~phines.’~ Iron dicarbonyl dinitrosyl reacts with 1,2-bisdimethylarsino-tetrafluorocyclobutene (mab) to give (mab)Fe(NO) . Mossbauer studies have been carried out on this complex and also on a range of compounds of type LFe(CO)(NO), for which the n-acceptor strengths of L are then said to increase in the order Ph,P < Ph,PMe (!) AsPh < (PhO),P < CO < NO.91 The i.r. spectrum of solid tricarbonylnitrosylcobalt has been studied as a function of temperature.Doublet structure appears in some doubly degenerate bands but only below 248 K at which temperature an order-disorder process takes place. The non-degenerate bands are not split. A band at 313 cm-’ is not due to vibrationally excited species since it persists at 100 K and is assigned to a Co-C-0 bending mode.” The exchange of Co(CO),(NO)PPh with I4CO follows a 2-term law. The bimolecular part is little influenced by solvent but good donor solvents increase the first-order contribution presumably by an S,l(S) me~hanism.~ With halides Co(CO),NO gives rise to ions Co(CO),X(NO)-. These react with benzyl chloride [presumably uia the loss of PhCHzNO from PhCH,Co(CO),(NO)X-] to yield PhCH :NOH.94 The polarographic reduc-tion of Co(CO),NO and also of the triphenylphosphine and triphenylarsine derivatives has been examined ; the expected correlation between v(N0) and half-wave potential is found.95 Carbonyl Phosphines Arsines Phosphine Hydrides and Related Compounds.-Dipole moment measurements in conjunction with i.r.data have been used to compare the bonding of different ligands to metal carbonyls; it is concluded that triphenylphosphine is both a better a-donor and a better n-acceptor than tri-phenylarsine and triphenyl~tibine.~~ The photoelectron spectra and ionization potentials of Cr(CO),PF C,H,Mn(CO),PF, the mixed iron carbonyl-phos-phorus trifluoride complexes and Ni(PF,) have been reported ; phosphorus trifluoride appears to be on balance more charge-withdrawing than carbon monoxide.’ 8 9 G. Paliani S.M. Murgia and G . Cardaci J. Organometallic Chem. 1971,30,221. 90 G. Cardaci and S. M. Murgia J. Organometallic Chem. 1970 25 483. 91 J. P. Crow W. R. Cullen F. G. Herring J. R. Sams and R. L. Tapping Inorg. Chem., ’* R. Cataliotti G. Paliani and A. Poletti Chem. Phys. Letters 1971 11 58. 93 G. Reichenbach J. Organometallic Chem. 1971 31 103. 94 M. Foa and L. Cassar J. Organometallic Chem. 1971,30 123. 9 5 R. Pfibil jun. J . MaSek and A. A. Week Inorg. Chim. Acta 1971 5 57. 9 6 C. Barbeau and J. Turcotte Canad. J . Chem. 1970,48 3583. 9 7 J. Miiller K. Fenderl and B. Mertschenk Chem. Ber. 1971 104 700. 1971,10 1616 430 P. S . Braterman Photochemical substitution gives a direct and convenient method of introduc-ing phosphine ligands into carbonyl anions of V- Nb- ' and Ta-Changes in phosphorus-fluorine coupling constants in complexes of the ligands PF,(Bu'),-, have been taken as a measure of n-bonding; this leads to the (rather surprising) order Ni(CO) < Cr(CO) < Mo(CO) < W(CO) for the It-donor power of the metal carbonyl fragments." A range of compounds of type M(C0)6-,L [M = Cr Mo or W; L = MeP(OMe) or MeP(NMe,),] have been prepared and their i.r.spectra examined ; the results lead to an ordering ofn-acceptor strength'" P(NMe,) < MeP(NMe,) < Me,P < MeP(OMe) < P(OMe) (which if correct could only be explained by nitrogen-to-phosphorus n-donation). The 183W n.m.r. shifts in the cis- and trans-isomers of (Bu",P),-W(CO) have been measured ; the value is greater for the trans-isomer and trends seem to parallel those in tungsten-phosphorus coupling constants."' The mass spectra of the tris(dimethy1amino)arsinepentacarbonyls of chromium molyb-denum and tungsten have been analysed; loss of the Me,N fragment is more prominent than in the spectra of the phosphorus analogues and the tungsten complex even gives series of ions Me,NAsW(CO),+ and AsW(CO),+.The iron carbonyl complex has also been examined and there is a metastable peak for loss of ASH from the ion of composition ( M ~ N ) A s F ~ H + . ' ~ ~ An electron diffraction study has appeared on F,PMo(CO) ; distances obtained include metal-carbon (206 pm) carbon-oxygen (1 15 pm) metal-phosphorus (237 pm), and phosphorus-fluorine (156 pm); the FPF angle is 990.1°3 The crystal struc-ture of the bridged complex (OC)5Mo~PEt2-PEt2.Mo(CO) has been determined ; the conformation about the phosphorus-phosphorus bond is staggered trans,'04 as had been inferred'" from i.r.and combination spectra for the methyl analogue. The cation [tralzs-Mo(CO),(dppe),] + (dppe = bisdiphenylphosphinoethane) can be prepared by the use of NOPF as an oxidizing agent. [This reagent also causes one-electron oxidation of Mn(CO),(PMe,Ph),Br but Pt0(PPh3) gave Pt(PPh3)42 +.Io6] trans-Mo(CO),(dppe) + is also obtained by air oxidation of the neutral species which for Mo has the cis-configuration; however cis-Cr(CO),(dppe) is bogus being a mixture of trans-Cr(CO),(dppe) and salts of the corresponding cation generated as an impurity.'" Several reactions of phosphines in metal carbonyl complexes have been re-ported.Thus the dimethylamino-groups in (Me,N),PMo(CO) successively react with HCl with loss of dimethylamine and the formation of phosphorus-chlorine bonds. Reaction with HI gives Mo(CO),P(NMe,)I . Over a period 9 8 A. Davison and J. E. Ellis J . Organometallic Chem. 1971 31 239. 9 9 0. Stelzer and R. Schmutzler J . Chem. SOC. ( A ) 1971 2867. l o o C. E. Jones and K. J. Coskran Znorg. Chem. 1971,10 5 5 . l o l P. J . Green and T. L. Brown Znorg. Chem. 1971 10,206. ' 0 3 D. M. Bridges G. C. Holywell D. W. H. Rankin and J. M. Freeman J . Organometallic R. B. King and T. F. Korenowski Org. Mass Spectrometry 1971,5 939. Chem. 1971,32 87. L. R. Nassimbeni Inorg. Nuclear Chem. Letters 1971 7 187. P. S. Braterman and D . T. Thompson J . Chem. SOC. ( A ) 1968 1454.' 0 6 R. H. Reimann and E. Singleton J . Organometallic Chem. 1971 32 C44. l o ' P. F. Crossing and M. R. Snow J . Chem. SOC. ( A ) 1971,610 Transition-metal Carbonyl Organometallic and Related Complexes 43 1 of hours Mo(CO),PCl is converted by methanol into Mo(CO),P(OMe) .Io8 Phosphinepentacarbonylmolybdenum reacts with the PH2 - anion to give [PH,Mo(CO),]- ; this itself is a powerful enough donor to react with excess Mo(CO),PH giving the (OC),MoPH,Mo(CO),- anion.'0g The neutral analogues (OC),MPMe2M'(C0)5 (M = Cr Mo or W ; M' = Mn or Re) have been prepared by nucleophilic attack of M'(CO) - on photochemically generated M(CO)5PMe2CI.' Stibine has been introduced as a ligand into metal hexacarbonyls by an indirect photochemical method giving (OC),CrSbH3 and the molybdenum and tungsten analogues.From its effect on the carbonyl i.r. spectrum stibine is classified as a better n-acceptor than triphenylstibine ; this parallels the comparison between PH3 and PPh,."' A range of Group IV-substituted phosphines have been introduced into the Group VI metal carbonyls; the proton and phosphorus n.m.r. spectra as well as i.r. and U.V. data are presented and discussed."2 Steric effects in the phosphine and arsine substitutions of molybdenum and tungsten carbonyl halides have been re~iewed."~ The crystal structure of MO(CO)~(PP~,),B~ shows highly distorted octahedral co-ordination ; the angle between the two metal-phosphorus bonds is 128°.1'4 In Mo(dam),(CO),Br (dam = bisdiphenylarsinomethane) and the tungsten analogue the metal is found to be seven-co-ordinate with a carbonyl group capping one face of an octahedron and one of the (dam) ligands being co-ordinated only at one end."5 The low-temperature limiting n.m.r.spectrum shows this structure to persist in solution. At intermediate temperatures there is loss of the distinction within each (dam) ligand and at room temperature the distinction between the two ligands is lost on the n.m.r. time-scale."6 Nucleophilic attack on co-ordinated chlorophosphines takes place in the reactions of (n-CSH,)Mn(C0)2PC13 and (n-CSH,)Mn(C0)2PPhC12 with boro-hydride giving (n-C5H,)Mn(C0)2PH3 and (n-CSH,)Mn(CO),PH2Ph.' The products from the reaction of manganese pentacarbonyl hydride with phosphines P(CF3),X depend critically on the nature of X.Thus simple substitution occurs for X = F CF or Me to give both cis- and trans-isomers of HMn(CO),P(CF,),X. For X = C1 the phosphide-bridged chloride-bridged species (OC),Mn(Cl)-[P(CF,),]Mn(CO) is obtained as well as Mn(CO),Cl whereas (CF,),PBr and (CF,),PI give merely the metal pentacarbonyl halides.' l8 The reaction of M. Hofler and W. Marre Angew. Chem. Internat. Edn. 1971 10 187. I o 9 G. Becker and E. A. V. Ebsworth Angew. Chem. Internat. Edn. 1971 10 186. ' l o W. Ehrl and H. Vahrenkamp Chem. Ber. 1971,104 3261. ' E. 0. Fischer W. Bathelt and J. Miiller Chem. Ber. 1971 104 986. H. Schumann 0. Stelzer J. Kuhlmey and U. Niederreuther Chem. Ber. 1971 104, 993. R. Colton Co-ordination Chem. Rev. 197 1 6 269. M. G. B. Drew I . B. Tomkins and R. Colton Austral.J . Chem. 1970 23 2517. M. G. B. Drew A. W. Johans A. P. Wolters and I. B. Tomkins Chem. Comm. 1971, 819. M. W. Anker R. Colton and C. J. Rix Austral. J . Chem. 1971 24 1157. M. Hofler and M. Schnitzler Chem. Ber. 1971 104 31 17. ' ' 'I4 ' I 8 R. C. Dobbie J . Chem. Sac. ( A ) 1971 230 432 P . S . Braterman dimanganese decacarbonyl with 1,2-bis(dimethylarsino)tetrafluorocyclobutene (mab) gives the bridged product (26) characterized by X-ray crystallography.' The potentially quadridentate ligand (Ph,PCH,),C however causes dis-proportionation of the carbonyl giving the salt Ph2PCH,C(CH2PPh2),-Mn(CO),+ Mn(CO),- in which the ligand uses three of its co-ordinating F2cx"'"'2'"i"co~4 AsMe +Mn(C0)4 F2C groups. [Similarly Co2(C0) gives P~,PCH,C(CH,PP~,),CO(CO)~~ CO(CO),-.'~~] The crystal structure of cis-(OC),Mn(PPh,)Cl has been deter-mined.The metal-carbon distances trans to chlorine and trans to phosphorus are equal (175 pm) while those trans to each other are lengthened to 184 pm.',' The 57Fe-'3C coupling in Fe(CO), and 57Fe-31P coupling in the tetra-carbonyliron complexes of PEt PEt,Ph and PEtPh have been measured at room temperature; in the carbonyl phosphines the 13C n.m.r. spectrum shows only one signal [as in Fe(CO),] split by coupling to phosphorus. It is concluded that in both the substituted and the unsubstituted carbonyls there is rapid averaging of axial and equatorial CO groups by an intramolecular process.'22 The crystal structures of trimethylarsine- and trimethylstibine-iron tetracarbonyls have been determined; in both cases the expected axially substituted trigonal-bipyramidal structure is found with an angle of 92" between bonds to axial and equatorial carbonyls.123 Reactions of phosphines co-ordinated to the tetra-carbonyliron group include conversion of Et2NPF2Fe(CO) by hydrogen chloride into ClPF,Fe(CO) (compare reference 108) and of BrPF,Fe(CO) into NCSPF,Fe(CO) by silver thiocyanate. Reaction of trans-Fe(CO),(PPh,)2 with nitrosonium tetrafluoroborate gives quantitative replacement of CO by NO' to yield Fe(CO),NO(PPh,),+. The ruthenium analogue is obtained by the reaction of Ru,(CO),(PPh,) a reaction not shown by the more strongly bonded osmium cluster compound ; however, Os(C0),N0(PPh3),+ may be isolated from the reaction of Os(CO)(NO)-(PPh,),Cl with carbon monoxide in the presence of NaBPh,.Both the iron and the osmium complexes undergo reversible nucleophilic attack on co-ordinated carbonyl according to the equation'25 MeO-M(C0),N0(PPh3),+ M(CO)(NO)(PPh,),CO,Me J. P. Crow W. R. Cullen F. L. Hou L. Y . Y . Chan and F. W. B. Einstein Chem. Comm. 1971 1229. J. Ellermann and W. Uller Z . Naturforsch. 1970 25b 1353. l z 1 H. Vahrenkamp Chem. Ber. 1971,104 449. l Z 2 B. E. Mann Chem. Comm. 1971 1173. J.-J. Legendre C. Girard and M. Huber Bull. SOC. chim. France 1971 1998. W. M. Douglas and J. K. Ruff J . Chem. Sac. ( A ) 1971 3558. l i 5 B. F. G. Johnson and J. A. Segal J . Organometallic Chem. 1971 31 C79 Transition-metal Carbonyl Organometallic and Related Complexes 433 Reaction of (C6F5AS) with iron pentacarbonyl gives (C,F,As),Fe(CO) , characterized crystallographically as (27).With (C,F,P), products ofcomposition Fe,(CO),(PC,F,) and Fe,(CO),(PC,F,) are obtained.'26 The stereochemistry i" C,F As (27) of substitution by phosphines into [Fe(CO),SMe] and [Fe(CO),SPh] has been studied by Mossbauer spectro~copy.'~~ It has also been shown that separation of the two isomers of [Fe(CO),SMe] (which differ only in the configuration of the methyl groups within the puckered Fe2S2 ring) followed by substitution, gives products in which the original configuration is retained.',* Reaction of (n-C,H,)Fe(CO)(PPh,)Me with phosphites gives products (n-C,H,)Fe(CO) [P(OR),]Me which undergo sulphur dioxide insertion into the iron-methyl bond. The propionyl compound (n-C,H,)Fe(CO)(PPh,)COEt may be converted successively into the ethyl the hydride and (by reaction with solvent chloroform) the chloride.Photochemical reaction of (n-CSH,)Fe(C0)2.Et with triphenylphosphine gives (n-C,H,)Fe(CO)(PPh,)Et directly ; the mechan-istic significance of this result may be limited since acyl complexes of this class decarbonylate to the corresponding alkyls under the influence of light. 29 The reaction of cyclopentadienyliron dicarbonyl alkyls with trialkylphosphines (acetonitrile behaves similarly) also gives products (n-C,H ,)Fe(CO) (PR' ,)COR2 ; the methylene protons in R' and R2 show diastereotopic shielding by the asym-metric iron atom. The kinetics of this reaction suggest a pre-equilibrium within the iron compound and in the absence of spectroscopic evidence for a solvated acyl the intermediate is formulated as containing an alkyl bridge between iron and CO (there is no evidence for this formulation either).Reaction of the acyls (R2 # Me) with triphenylmethyl chloride gives the cations (n-CsH5)-Fe(CO),L+ presumably by a /I-hydride abstraction process (see Scheme l).',' L I I II co 0 (n- C H )Fe - C - w - C H -/H1(? P h Scheme 1 Phosphide-bridged compounds may be obtained by nucleophilic attack on CIPPh,Fe(CO) (compare ref. 110); (n-C5H,)Fe(CO)2PPh,Fe(CO) may be obtained in this way or by reaction of (n-C,H,)Fe(CO),PPh [from the '" J. A. De Beer R. J. Haines R. Greatrex and N. N . Greenwood J . Organometallic P. S. Elmes P. Leverett and B. 0. West Chem. Comm. 1971 747. Chem. 1971,27 C33.J. P. Crow and W. R. Cullen Canad. J. Chem. 1971,49,2948. S . R. Su and A. Wojcicki J. Organometallic Chem. 1971 27 231. M. Green and D. J. Westlake J . Chem. SOC. ( A ) 1971 367. 1 3 434 P. S. Braterman (n-C,H ,)Fe(CO) - anion and diphenylchlorophosphine] with di-iron ennea-carbonyl [species (n-C,H,)Fe(CO),-SR.Fe(CO) have also been observed but not isolated]. (n-C,H,)Fe(CO),PPh reacts with (n-C5H5)Fe(C0),C1 to give [(n-C ,H ,)Fe(CO),] PPh + C1 - and with [( 1,5-cyclo-oc tadiene)RhCl] and [Rh(CO),Cl] to give products of type (n-C,H,)Fe(CO),PPh,~RhL,Cl. Photo-1 ysis of (n-C H ,)Fe(CO),PPh Fe(CO) gives the metal-metal- bonded product (28a). This product has independently been obtained by treating (7c-C5H5)-Fe(CO),Cl with Fe(CO),PPh,H which also reacts with (7c-C5H,)Ni(CO)I to 0 C / \ \ f P M -Fe(CO), Ph’ ‘Ph (28) (a) M = (x-C,H,)Fe(CO) (b) M = (x-C5H5)Ni give (28b).32 The phosphine-bridged species [(n-C,H,)Fe]2(CO),[Ph,P(CH2)3-PPh,] undergoes reversible 1- and 2-electron oxidation ; the 1-electron oxidation product reacts with acetonitrile to give a mixture of starting material and [(n-C,H,)Fe(CO)(NCMe)]2[Ph,P(CH2)3PPh2]2+.133 The reaction of the hexachloro-osmate(1v) anion in alcoholic solvents with PCx (Cx = cyclohexyl) gives OsHCI(CO)(PCx,) . 134 Reaction of bis(tripheny1-phosphine)ruthenium tricarbonyl with carboxylic acids gives products (RC02),-Ru(CO),(PPh,) . In these spectroscopic evidence indicates that the carboxylate groups are bonded through one oxygen only and are mutually trans both carbonyl and phosphine ligands being mutually cis.Both Ru,(CO)~(PP~,) and Ru(CO),PPh give the known dimers Ru,(CO),(PPh,),(RCO,) . 13’ Reaction of Ru,(CO), with (mab) gives (29).’36 A range of trimethyl phos-phite derivatives of H,Ru,(CO), containing up to four phosphites substituted for 1 3 1 1 3 2 1 3 3 1 3 4 1 3 5 1 3 6 carbonyl has been prepared. The n.m.r. spectrum and the simplicity of wAsMe2 Me,As F2C-CF2 (29) R. J. Haines C. R. Nolte R. Greatrex and N. N. Greenwood J . Organometallic Chem. 1971,26 C45. K. Yasufuku and H. Yamazaki J. Organometallic Chem. 1971 28,415. J. A. Ferguson and T. J. Meyer Chem. Comm. 1971 1544. F. G. Moers Chem. Comm. 1971 79. B. F. G. Johnson R. D. Johnston J. Lewis and I. G. Williams J . Chem. SOC. ( A ) , 1971 689.P. J. Roberts and J. Trotter J . Chem. SOC. ( A ) 1971 1479 Transition-metal Carbonyl Organometallic and Related Complexes 435 chromatographic behaviour indicate that only one isomer of each species is formed. In all cases the four hydride ligands are equivalent and equally coupled to all phosphorus atoms present indicating a rapid averaging of hydride environ-m e n t ~ . ' ~ ' A range of compounds of types RuC12(CO)L2 trans-Rh(CO)L2X and the iridium analogue RhCl,(CO)L2 and the iridium analogue and nickel, palladium and platinum complexes of type MX,L have been prepared where L = di-(t-buty1)phosphine and X is a ha10gen.l~~ Reaction of tris(tripheny1-phosphine)dichlororuthenium with hydrogen followed by carbon monoxide in dimethylacetamide gives RuClH(CO),L ; a range of related reactions are discussed.139 The isomerization of olefins by RuCl,(PPh,) is greatly accelerated by traces of hydroperoxides which give rise to a catalytically active compound with ligand carb0ny1.l~' One two three or four trimethyl phosphite ligands may be substituted for CO in CO,(CO)~~ ; the i.r. spectrum shows the presence of bridging CO but there is no evidence of isomer^.'^' A range of compounds of the type HCo(CO),-,,-(PBu",) have been described. They are hydrogenation and isomerization catalysts ; the catalysis is depressed by excess phosphine. It is suggested that much of the difference between catalysis by Co,(CO) and by [Bu",PCo(CO),] is due to the use of lower CO pressures with the latter.142 Anions [Co(CN),(CO)-(PR,)] - [CO(CN)~(CO)~(PR,)]- and neutral Co(CN)(CO),(PR,) have been prepared by reaction of trialkylphosphines with the [Co(CN),(C0),I2 - anion.Reversible protonation with a pK of around 5 has been demonstrated for [Co(CN),(CO)(PEt,),] - . The anions are poor nucleophiles in this resembling cobalt(1) in carbonyls rather than in dimethylglyoximato-complexes. 143 Reaction of dicobalt octacarbonyl with (mab) gives (30);14 the product from ffars and Co,(CO),CCF rearranges to give (31).'45 AsMe2 F*C -CF, (30) (31) M = Co(CO), The out-of-plane M-C-0 bending frequency in the complexes trans-RhX(C0)-(PPhj) decreases from X = F to X = I but also decreases on oxidative addition 13' S. A. R. Knox and H. D. Kaesz J . Amer. Chem. SOC. 1971,93,4594. 1 3 8 A. Bright B.E. Mann C . Masters B. L. Shaw R. M. Slade and R. E. Stainbank, 1 3 9 B. R. James and L. D. Markham Inorg. Nuclear Chem. Letters 1971 7 373. I 4 O J. E. Lyons Chem. Comm. 1971 562. 14' D. Labrone and R. Poilblanc Compt. rend. 1970,271 C 1585. 14' G. F. Pregaglia A. Andreeta G. E. Ferrari and R. Ugo J . Organometullic Chem., 1 4 3 J. Bercaw G. Guastalla and J. Halpern Chern. Comm. 1971 1594. 144 W. Harrison and J. Trotter J . Chem. Soc. ( A ) 1971 1607. 1 4 5 F. W. B. Einstein and R. D. G. Jones J. Chem. SOC. ( A ) 1971 3359. J . Chem. Soc. ( A ) 1971 1826. 1971 30 387 436 P. S . Braterman to the complexe~.'~~ In complexes of the type trans-RhX(CO)(PR,), there is a linear correlation between the chemical shift of free ligand phosphorus and the change in chemical shift on co-ordination ; however there is no clear correlation between phosphorus-rhodium coupling constant and carbonyl stretching fre-q ~ e n c y .' ~ ~ The low-temperature ,'P n.m.r. spectra of compounds of type trans-RhCI(CO)(PRBu',) and their iridium analogues show the presence of three rotamers (32a b and c); the isomers containing two non-equivalent phos-phorus atoms are readily identified but there seems no direct way of deciding to /But But But \ \ P-R P-R But/ 1 But/ I R-[\But Cl-M-CO Cl-M-CO Cl-M-CO I /But R-P I /But Bu' 1 Bu' But Bu' P-R R-P \ / \ \ (a) (b) (4 (32) L. 1 4 6 1 4 7 1 4 8 1 4 9 1 5 0 1 5 1 1 5 2 which of the remaining isomers each of the remaining spectra belongs. The chemical shift differences between rotamers are up to 15 p.p.rn.l4* The rhodium and iridium carbonyl fluorides trans-MF(CO)(PPh,) react with a range of anions A- [e.g.CN ONO, OClO, OC(O) OH] to give products MA(Cl)(PPh,),. An attempt to use the CO frequency as a measure of the total electronegativity of A which is then treated as a sum of CT- and n-bonding terms, leads to what the reviewer regards as unsatisfactory r e ~ u 1 t s . l ~ ~ An equilibrium has been demonstrated between IrH(CO)(PPh,) plus hydro-gen and IrH,(CO)(PPh,) plus triphenylphosphine ; there is kinetic evidence that equilibration proceeds via IrH(CO)(PPh,) which also appears to be the active catalyst for hydrogenation in this system. 5 0 Hydrogenation catalysis by RhCl(CO)(PPh,) in fact proceeds via RhH(CO)(PPh,) formed by the action of base or after an induction period ; but IrCI(CO)(PPh,) which can co-ordinate an extra ligand is a good catalyst as In the systems IrX(CO)L (L = phosphine) reactivity for hydrogenation generally increases in order X = I < Br < C1; no regularity is apparent in the effects of varying T 152 The reaction of Rh4(C0)12 with phosphines and phosphites produces Yu.S. Varshavskii M. M. Singh and N. A. Buzina Russ. J . Inorg. Chem. 1971 16, 725. B. E. Mann C. Masters and B. L. Shaw J . Chem. SOC. ( A ) 1971 1104. B. E. Mann C. Masters B. L. Shaw and R. E. Stainbank Chem. Comm. 1971 1103. L. Vaska and J. Peone jun. Chem. Comm. 1971,418. M. G . Burnett and R. J. Morrison J . Chem. SOC. ( A ) 1971 2325. W. Strohmeier W. Rehder-Stirnweiss and R. Fleischmann Z .Naturforsch. 1970, 25b 1480 1481. W. Strohmeier R. Fleischmann and T. Onoda J . Organometallic Chem. 1971 28, 281 Transition-metal Carbonyl Organometallic and Related Complexes 437 di- tri- and tetra-substituted derivatives ; Rh,(CO), gives products Rh6(cO),&,. In the presence of carbon monoxide the reactions with tri-phenylphosphine and triphenylarsine give the bridged products L (CO)Rh(CO),-Rh(CO)L ; tri-n-butylphosphine gives a non-bridged product. Some rhodium carbonyl phosphine compounds are very active hydroformylation catalysts for alk- 1 -enes.' 53 Tris(tripheny1 phosphite)nickel carbonyl can be prepared either by triethyl-aluminium reduction of nickel bis(acety1acetonate) in the presence of the phos-phite and carbon monoxide or by reaction of Ni[P(OPh,)] with CO.', The ligand ferrocene-1,l'-bis(dimethy1arsine) (fdma) reacts with nickel carbonyl to give Ni(CO),(fdma) ; this is oxidized by iodine to Ni(CO)(fdma)I unusual in being a carbonyl of Ni" for which the C-0 stretching wavenumber15 is 2054 cm- '.Diphenylphosphinenickel tricarbonyl reacts with (n-CsH ,)Ni(CO)I to give the phosphide-bridged species [(n-C,H,)Ni],[PPh,] ; reaction with (7c-CsH,)Fe(CO),I gave (n-C,H,)Fe(CO),PPh,Ni(CO) which could not be converted into a condensed system. ' 32 2 Organometallic Complexes One-carbon Ligands.-Cyanides and Isonitriles. Cyanogen takes part in oxidative addition to phosphine complexes of nickel palladium and platinum giving products C,M(CN) . With tris(tripheny1phosphine)rhodium chloride an inter-mediate adduct of molecular cyanogen can be detected at 200 K; at room tem-perature only the cis-addition product can be detected.No reaction was ob-served between cyanogen and RhCl(CO)(PPh,) IrCl(CO)(PPh,) PtC1,-(PPr",) or AuClPPh . ' 5 6 Bis(tripheny1phosphine)platinum reacts with nitro-methane in wet benzene via (it is suggested) an intermediate (Ph,P),Pt(H)CH,-NO, to give eventually the fulminate (Ph,P),Pt(CNO) . l S 7 The reaction of a range of bis(methy1 isonitrile) complexes [M(CNMe),]+ [M = (n-C,H,)Mo(CO), (n-C,H,)MnNO or (n-C,H,)FeCO] with borohydride gives products formulated as the adducts (33a); these react with triphenylmethyl tetrafluoroborate to give (33b). The reaction between [(n-C,H,)Fe(CNMe),]' H Me C=Nf / \-2 C-N M /BX, H Me ( 3 3 ) M = (n-C,H,)MnNO or (n-C5H,)FeC0 (a) X = H (b) X = F H Me /C=N; \ ""/ dC-N,- (n-C,H,)Fe BH C-N H Me (34) 1 5 3 1 5 4 1 5 5 1 5 6 1 5 7 B.L. Booth M. J . Else R. Fields and R. N. Haszeldine J. Organometallic Chem., 1971 27 119. J. R. Olechowski J. Organometallic Chem. 1971 32 269. J. J. Bishop and A. Davison Znorg. Chem. 1971 10 832. M. Bressan G. Favero B. Corain and A. Turco Znorg. Nuclear Chem. Letters 1971, 7 203. W. Beck K . Schorpp and F. Kern Angew. Chem. Znternat. Edn. 1971,10,66 438 P . S . Braterman and borohydride gives (34).158 The reaction between Fe(CNMe),SO4 and (36) (a) L = CO (35) (b) L = PPh, excess methylamine in methanol gives (35).15 cations (36) have been generated by the reaction sequence Ruthenium isonitrile hydride RNC AgCIO RuHCI(CO)(PPh,) RuHC~(CO)(CNR)(PP~,)~ RuH(OC~O,)(CO)(CNR)(PP~,), 5 [RuH(CO)(CNR)L(PP~,)~]+ C10,- (L = CO or PPh,) These hydrides are slowly deprotonated by bases and it is suggested (by analogy with related studies on osmium compounds) that the mechanism of proton loss is addition of hydroxide or alkoxide followed by reductive elimination of water or alcohol.Protonation of the deprotonated species derived from (36a) gives (37).I6O PPh, Ru OC' I 'CNR PPh, \ I /co H (37) The hydrolysis of (Ph P)2 Rh(CNMe)CI gives (Ph,P)2 Rh(CO)C1.'6 ' Reaction of ethylenebis(tripheny1phosphine)platinum with t-butyl isonitrile gives (Ph3P)2-Pt(CNBu') ; this reacts with carbon monoxide to give (Ph,P),Pt(CNBu')(CO), and undergoes oxidative addition with a variety of species XY (I2 Mel CF,I, Ph,SnCl) to give products (Ph3P),Pt(CNBu'),XY.In nitromethane the iodine-containing species have been shown to be 1 1 electrolytes and thus contain five-co-ordinate platinum(Ir).'62 Addition of hydroxide to [trans-(Ph,P),Pt(CNMe)J2 + gives [trans-(Ph,P),Pt(CNMe)-C(O)NHMe] + ; [(Ph3P)2-P t( CNMe)C( S)NH Me] + and species [ (Ph 3P)2 Pt (CN M e).C(NR)NHMe] + may be prepared ~ i m i l a r l y . ' ~ ~ A closely related reaction is that between complexes of the type cis-PtX2(CNR1)PR2 and alcohols to give carbene complexes such as C12Pt(PR2,) C(0Me)NHR and C12Pt(PR2,) C(NHMe)NHR'. Reduction of the isonitrile complexes with sodium borohydride gives hydrocarbon^.'^^ 15' P. M. Treichel J. P. Stenson and J. J. Benedict Znorg.Chem. 1971 10 1183. 1 5 9 J. Miller A. L. Balch and J. H. Enemark J . Amer. Chem. Soc. 1971,93 4613. 1 6 ' D. F. Christian and W. R. Roper Chern. Comm. 1971 1271. 1 6 ' A. L. Balch and J. Miller J . Organometallic Chem. 1971 32 263. 1 6 ' G. A. Larkin R. Mason and M. G . H. Wallbridge Chem. Cornm. 1971 1054. 1 6 3 W. J. Knebel and P. M. Treichel Chem. Comm. 1971 516. 1 6 4 E. M. Badley J . Chatt and R. L. Richards J . Chem. SOC. ( A ) 1971 21 Transition-metal Carbonyl Organometallic and Related Complexes 439 Carbene Complexes. The reaction of metal carbonyls with Grignard reagents RMgX to generate carbene precursors M C(0-)R unlike the analogous reac-tion of RLi is slow enough for kinetic studies to be possible. It is found that the reaction of triphenylphosphinetungsten pentacarbonyl is slower than that of tungsten hexacarbonyl in agreement with the prediction that ease of nucleo-philic attack at carbon should increase with CO stretching frequency.The i.r. spectra of a range of carbene complexes have been examined and both frequency and intensity patterns analysed; it is concluded that the carbene ligand is a n-acceptor. 16' Several groups have used the i.r. spectra of pentacarbonylchromium carbenes as a measure of the electron demand of R in such compounds as (OC),-CrC( 0Me)R. In the p-phenylene derivatives (OC)&rC(OMe)C6H,X the CO force constants correlate with the a-parameters of X. The U.V. spectra are also sensitive to the nature of X and the lowest energy band is provisionally assigned to a Cr(3d) -P carbene(z*) charge transfer.The electron-withdrawing character of pentafluorophenyl and the electron-donating nature of ferrocenyl, have been demonstrated by this t e ~ h n i q u e . ' ~ ~ The reaction of primary amines with (OC),CrC(OMe)Ph gives products (OC),CrC(NHR)Ph [pyridine (py) gives a mixture of Cr(CO),(py) and cis-Cr(CO),(py) the latter presumably arising via Cr(CO),(py)(~arbene)].'~~ The rate of the former reaction is proportional to [Cr(CO),C(OMe)Ph] [RNH,] [HX] [Y] where HX is a proton donor and Y a proton acceptor. This is consistent with an essentially bimolecular nucleo-philic attack by RNH (activated by Y) on the carbene (activated by HX) (Scheme 2); hydrogen bonding of the kind suggested in the Scheme has been y H I R/NH L r l Ph -C Cr(CO), x -H- .>o - M ~ Scheme 2 demonstrated by n.m.r.16' In the presence of acetaldehyde ammonia gives (OC),CrC(N CHMe)Ph as well as (OC),CrC(NH,)Ph.' 70 The bis-carbene complex (MeFkCH CH.NMed ),Cr(CO) has been prepared by irradiation of the mono-carbene in boiling THF.17' In the compound (n-C,H,)Cr(NO)-(CO) and its molybdenum and tungsten analogues only one carbonyl group is 1 6 ' D.J. Darensbourg and M. Y. Darensbourg Inorg. Chim. Acta 1971 5 247. 1 6 6 E. 0. Fischer C. G. Kreiter H. J. Kollmeier J. Muller and R. D. Fischer J. Organo-1 6 ' G . A. Moser E. 0. Fischer and M. D. Rausch J. Organometallic Chern. 1971 27, 168 E. 0. Fischer B. Heckl and H. Werner J. Organometallic Chem. 1971 28 359. metallic Chem. 1971 28 237. 379. H . Werner E. 0.Fischer B. Heckl and C. G. Kreiter J. Organometalfic Chem. 1971, 28 367. L. Knauss and E. 0. Fischer J. Organometallic Chem. 1971 31 C68. K. Ofele and M. Herberhold Angew. Chem. Internat. Edn. 1970,9 739 440 P . S . Braterman converted into carbene on treatment with phenyl-lithium followed by trimethyl-oxonium Salts.' 7 2 The complex (n-C6H6)Cr(CO)2 C(0Me)Ph shows four bands in the carbonyl stretching region ; the spectrum is essentially solvent-independent and is assigned to the presence of two isomers due to restricted rotation about the metal-carbene-carbon bond. ' 73 A large number of metal acyls have been shown to react with proton acids to give hydroxy-carbene complexes according to the equation MeCO-M + H + + MeC(0H)M' [M = e.g. (71-C,H,)Fe(CO)PCx, (n-C5H5)Mo(CO),PCx3, (x-C,H,)RU(CO)~ (x-C~H~)RU(CO)PP~~] Use of trialkyloxonium salts in place of acid gives the corresponding alkoxy-carbenes.Borohydride reduction of the (n-C,H,)Fe(CO) (PPh,) C(OEt)Me+ ion gives (n-C,H,)Fe(CO)(PPh,)CH(OEt)Me the hydride addition product but methyl-lithium merely gives the parent acetyl complex propane and propene. 74 A simple dinuclear carbene of manganese has been prepared by the reaction of the pentacarbonylmanganese anion with the Lewis pseudo-acid methylmangan-ese pentacarbonyl. The resultant acyl- or oxy-carbene {cis-(OC),Mn-Mn-(CO),C(O)Me f-) cis-(OC),Mn-Mn(CO) C(0-)Me} reacts with (MeO),O+ to give cis-(OC),Mn-Mn(CO) :C(OMe)Me.' 75 In the platinum carbenes [MePtL,:C(OR')CH,R2]+ (L = Me2PhP or Me,As) generated by the reaction of trans-L2PtMeC1 in R'OH containing AgPF with the acetylene R2CCH the methyl-platinum stretching wavenumbers and coupling constants are low (ca.520 cm- ' and 50 Hz) indicating that carbene is a ligand with a strong trans influence.'76 Restricted rotation around the nitro-genxarbon bond has been inferred from the n.m.r. spectra of species trans-(Et3P)2Pt(X) C(Y)NHR+ (Y = PhNH EtNH or EtO) generated by addition of HY to a parent isonitrile c0mp1ex.l~~ In related complexes of type trans-(Me,PhP),Pt(CNEt) C(NHEt)Y there are four non-equivalent phosphorus-bound methyl groups yet only one isomer is present. It is inferred that there is restricted rotation around the platinum-carbene-carbon bond. ' Addition of monosubstituted hydrazines to (MeNC),Pd2 + gives the carbene complexes (38a),' 7 9 whereas refluxing [Et,PPtCl,] in xylene with 1,1f,3,3'-tetraphenyl-bi-* E.0. Fischer and H.-J. Beck Chem. Ber. 1971 104 3 101. 1 7 3 H.-J. Beck E. 0. Fischer and C. G. Kreiter J . Organometallic Chem. 1971 26 C41. 1 7 4 M. L. H. Green L. C. Mitchard and M. G. Swannick J . Chem. Soc. ( A ) 1971,794. 1 7 5 C. P. Casey and R. L. Anderson J . Amer. Chem. Soc. 1971,93 3554. 7 6 M. H. Chisholm and H. C. Clark Znorg. Chem. 1971 10 171 1 . 1 7 7 E. M. Badley B. J. L. Kilby and R. L. Richards J . Organometallic Chem. 1971 27, c 3 7 . 17' H. C. Clark and L. E. Manzer J . Organometallic Chem. 1971,30 C89. G. Rouschias and B. L. Shaw J. Chem. SOC. ( A ) 1971,2097 Transition-metal Carbonyl Organometallic and Related Complexes 441 imidazolylidene causes cleavage of the central carbon-carbon double bond to give (38 b).so R Ph \ + C-NHMe /N=N\ MeNH-C I / Pt 7 2 MeNC' CNMe c1 I Et 3P - Pt : I c1 I 0 N I Ph (384 (38b) Alkyl and Aryl Complexes. A review has appeared on the structures of transition-metal complexes containing a metal-carbon o-bond. 's ' The range of trimethylsilylmethyl (Me,SiCH,-,tsm) complexes has been extended by a further general study ; full details are given of reactions of tsmLi or tsm Grignard reagents with the appropriate metal halides giving rise to com-pounds of type cis-PtL,(tsm) trans-Pt(tsm)H(PEt,) cis-Pd(tsm),(PEt,) , trans-Pd(tsrn)Cl(PEt,) Ph,PAu(tsm) Co(tsm),(bipy) + (n-C,H,),Ti(tsm) , and Mn(tsm)(CO),. (The gold complex is described as extremely stable in unexplained contrast to the results of earlier workersls2 on what was plainly, from its physical properties an authentic sample of the same compound.) The strong trans influence of tsm comparable to that of CN is apparent from its effect on the trans-platinum-hydrogen coupling constant.In some cases direct comparison between tsm and neopentyl (Me,C.CH,-) complexes is possible ; those of tsm are more stable suggesting a positive factor in addition to the im-possibility of p-elimination and the tsm proton n.m.r. spectrum in the complexes of electron-rich metals may be interpreted as giving evidence for M+ Si P-(d-d)n-bondinglS3 (see also refs. 197 and 630). Europium and ytterbium metals react with alkyl and aryl iodides in THF to give Grignard analogues ; samarium reacts similarly but more sluggishly whereas gadolinium and erbium do not react.Lanthanium and cerium metals give what are probably tripositive derivatives in reactions involving precipitation ; the reaction of organolithium compounds with the metal halides gives a better route to these.Is4 The d' organometallics trimethyl- and triphenyl-titanium have been prepared by the use of Grignard reagents at 233 K; the intermediate Ph2TiCl was isolated as an etherate." Methyltitanium trichloride forms 2 1 adducts with a range of donors including THF and 1 1 adducts with bipyridyl and triphenylphos-phine ; all of these are more thermally stable than the uncomplexed material. lS6 I8O D. J . Cardin B. Cetinkaya M. F. Lappert Lj. Manojlovic-Muir and K.W. Muir, Chem. Comm. 1971,400. M. R. Churchill Perspectives Structural Chem. 1970 3 9 1 . ' lE2 A. Shiotani and H. Schmidbaur J. Amer. Chem. SOC. 1970 92 7003. 1 8 3 B. Wozniak J. D. Ruddick and G. Wilkinson J. Chem. SOC. ( A ) 1971 31 16. D. F. Evans G. V. Fazakerley and R. F. Phillips J. Chem. SOC. ( A ) 1971 1931. W. Schafer and K.-H. Thiele Z. anorg. Chem. 1971,381 205. 1 8 6 G. W. A. Fowles D. A. Rice and J. D. Wilkins J. Chem. SOC. ( A ) 1971 1920 442 P. S . Braterman MeTiC1 also co-ordinates chloride ion forming bridged species [(MeTiCl,j,-Cl,]- and [(MeTiCl,),C12]2- as well as MeTiC1,2-.'87 There has been a flurry of interest in the structures of tetrabenzyltitanium and its congeners; the spectroscopic evidence in this case is conflicting. The n.m.r.spectrum of (PhCH,),Ti depends on the method of preparation. If this involves the presence of pyridine the spectrum is that expected for a a-bonded complex, but in the absence of any such donor the spectrum indicates ligand n-co-ordina-tion."* The i.r. spectrum however is analysable in terms of pure a-bonds more readily than could be explained by allylic or ring co-ordination of the benzyl groups." A possible explanation of these seeming contradictions is provided by crystal structure determinations. Whereas the structure of tetrabenzyltin contains no unusual features tetrabenzylzirconium has a distorted structure in which the Zr-C-C angles range from 85" to 101" and C-1 of the phenyl ring is close enough to the metal atom (as little as 274 pm) for overlap between the ring n-system at this point and the vacant metal d-orbitals to be considerable.Tetra-benzylhafnium is isostructural with the zirconium analogue and tetrabenzyl-titanium is similarly distorted but with wider angles (from 92" to 1 15").'90 The crystal structure of (n-C,H,),TiPh has been determined; it contains no surprising features.'" This compound reacts with carbon dioxide at 360 K in xylene with elimination of benzene to give (39)19 [which like the products of other reactions of (n-C5H,)2TiPh, may be regarded as an insertion product of bis(cyclopentadienyl)titaniumbenzyne]. The reactions of 2,2'-dilithiobiphenyl and of (2-LiC6H,)C(Bu) C(Li)Ph with (n-C,H,),TiCl give the chelated pro-ducts (40) and (41) which are stable at room temperature even in air.'93 Reaction of benzyl Grignard with vanadium tetrachloride gives tetrabenzyl-vanadium which is stable under nitrogen to 360K.The well-resolved e.s.r. 1 8 ' R. J. H. Clark and M. Coles Chem. Comm. 1971 1587. 1 8 8 R. Tabacchi and A. Jacot-Guillarmod Helu. Chim. Acta 1970,53 1977. W. Briiser K.-H. Thiele P. Zdunneck and F. Brune J . Organometallic Chem. 1971, 32 335. 190 ( a ) G. R. Davies J. A. J. Jarvis B. T. Kilbourn and A. J. P. Pioli Chem. Comm., 1971 677; ( 6 ) G. R. Davies J. A. J. Jarvis and B. T. Kilbourn ibid. 1971 151 1 ; (c) I. W. Bassi G. Allegra R. Scordamaglia and G. Chiocola J . Amer. Chem. SOC. 1971, 93 3787. 1 9 ' V. Kocman J. C. Rucklidge R. J . O'Brien and W. Santo Chem. Comm. 1971 1340. l g 2 I. S. Kolomnikov T. S. Lobeeva V. V. Gorbachevskaya G.G. Alexandrov Yu. T. Struchkov and M. E. Vol'pin Chem. Comm. 1971 972. 1 9 3 M. D. Rausch and L. P. Klemann Chem. Comm. 1971 354 Transition-metal Carbonyl Organometallic and Related Complexes 443 spectrum of this compound is taken to indicate appreciable distortion from regular tetrahedral co-ordination (cf tetrabenzyltitanium above).194 The structure of Li,Cr2(C,H,),4Et20 has been determined ; the anion con-sists of two Cr(C4H8) units joined by a very short (198 pm) bond. The chromium atom of each unit is bonded 1,4 to each of the two tetramethylene groups making four chromium-arbon o-bonds ; as expected for a quadruply bonded (d"), system the two units are in the eclipsed c~nfiguration.'~~ An insoluble pre-sumably polymeric material of composition Ar,Cr (Ar = o-methoxyphenyl) has been prepared from the Grignard reagent and chromium(I1) bromide in THF; it is converted by bipyridyl in the presence of air into the cis-[Ar,Cr(bipy),]+ cation which is air-stable and has three unpaired spins.'96 The crystal structure of the diamagnetic material [(tsm),Mo] [previously misdescribed as (tsm),Mo] has been described.The molybdenum-molybdenum distance is 217 pm indicating multiple bonding and the two halves of the molecule are mutually staggered ; the tungsten compound is isostructural. The related compounds Mo,(CH,Ph) W,(CH,Ph) and Mo,(CH,CM~,)~ have been prepared by Grignard reactions and also show considerable ~tabi1ity.I~~ The structure of methylpentacarbonylmanganese in the vapour has been determined by electron diffraction.The methyl-manganese distance is 2 18 pm, and (assuming reasonable values for the manganese-carbonyl distances) the angle between axial and equatorial CO is found to be 95°.198 Reaction between pentacarbonylmanganese hydride and o-styryldiphenylphosphine (sp) gives mainly the compound Ph,P.C,H,-o-CH(Me)Mn(CO) (derivable by formal Markovnikoff addition of metal and hydrogen to the olefinic bond) with the anti-Markovnikoff product P~,P-C,H,-O-CH,CH,M~(CO)~ being formed in smaller amounts ; however the rhenium hydride gives exclusively the anti-Markovnikoff isomer.'99 With methyl-pentacarbonylmanganese sp gives (42) and (43).,0° Me (43) [Of these (42) is again derivable by addition of manganese and a covalently bonded group across the styrene double bond whereas (43) formation of which 1 9 4 S.D. Ibekwe and J. Myatt J . Organometallic Chem. 1971 31 C65. 1 9 ' J. Krausse and G. Schodl J . Organometallic Chem. 1971 27 59. 1 9 ' F. Huq W. Mowat A. Shortland A. C. Skapski and G. Wilkinson Chem. Comm., 19' H. M. Seip and R. Seip Acta Chem. Scand. 1970,24 3431. 199 M. A. Bennett and R. Watt Chem. Comm. 1971,94. 2"o ( a ) M. A. Bennett and R. Watt Chem. Comm. 1971 95; ( 6 ) M. A. Bennett G. B. 96 J. D . Daly F. Sanz R. P. A. Sneeden and H. H. Zeiss Chem. Comm. 1971,243. 1971 1079. Robertson R. Watt and P. 0. Whimp ibid. 1971 752 444 P . S. Braterman must involve a hydride shift contains the novel h3-oxa-ally1 group-ing.] Benzylideneaniline PhN CH-Ph reacts with MeMn(CO) to give PhN CH.C,H,-o-Mn(CO) the structure of which has been determined.The phenyl ring is twisted out of the plane of the rest of the ligand as in the free ligand itself but unlike azobenzene or stilbene.201 ( ~ p ) F e ( C 0 ) ~ and (sp)Ru(CO) (in which sp is acting simply as a bidentate ligand) undergo Markovnikoff addition of HCl or HBr (compare ref. 199) across the oleh-metal bond to give products Ph,b-C,H,-o-CH(Me)I!h(CO)3X.202 In (n-C,H,)Fe(CO),CH,Ph the ring of the benzyl ligand is readily deuteriated by CF,COOD in addition to undergoing cleavage reactions. Deuteriation could take place by protonation of the ring with n-bonding of the resultant CH,=C-(ring) bond to the metal but it is thought that a /?-interaction (compare ref. 190) between iron and C-1 of the ring increasing the electron density at and the basicity of the 0- and p-carbon atoms is more probably responsible.This view is sup-ported by the low energy of the charge-transfer band from the ring to tetra-~yanoethylene.~~~ The solids from the systems which in solution undergo equilibria I t M'(naphtha1ene) (dmpe) M"(naphthy1) (H) (dmpe), (M = Ru or 0 s ; dmpe = 1,2-bisdimethylphosphinoethane) have been shown to contain the naphthyl hydride isomers ; hydrogen and naphthyl are mutually cis the metal-aryl carbon bonds are abnormally long and the metal-phosphorus bond trans to hydrogen is 5 pm longer than that trans to carbon.,' NN'-Ethylenebis(salicylideneiminato)cobalt(III)ethyl is a centro-symmetric dimer [(salen)CoEt] with an oxygen from each unit co-ordinating the cobalt atom of the other.205 The presence of Me(dmg),CoCO in equilibrium with [(dmg),CoMe] (dmg = dimethylglyoximato) has been demonstrated spec-troscopically; both v(C0) (2115 cm-') and the downfield shift of the methyl protons in the CO complex (relative to the dimer) show that CO is acting to some small extent as a n-acceptor.206 Cobaltkarbon bonds are formed in the reaction of Co"(sa1oph)L with p-cyanobenzyl halides [saloph = NN'-bis(sa1i-cy1idene)-o-phenylenediamino ; L is e.g.a nitrogen or phosphorus ligand] ; the rate-determining step is attack of Co" on the halide to give the Co"' halide and a rapidly reacting radical.207 Phenylcobalt(II1) complexes of Schiff bases such as salen undergo reversible electrochemical reduction uia Co" to the phenylcobalt(1) complex ; further reduction cleaves the metalkarbon bond.208 Alkylcobaloximes 2 0 1 M.I. Bruce B. L. Goodall M. Z . Iqbal F. G . A. Stone R. J. Doedens and R. G . Little Chem. Comm. 1971 1595. 202 M. A. Bennett G . B. Robertson I. B. Tomkins and P. 0. Whimp J . Organometallic Chem. 1971,32 C19. 203 S. N. Anderson D . H. Ballard and M. D. Johnson Chem. Comm. 1971,779. 204 V. A. Gregory S. D. Ibekwe B. T. Kilbourn and D. R. Russell J. Chem. SOC. ( A ) , 1971. 1118. 2 o s M. Calligaris D . Minichelli G . Nardin and L. Randaccio J . Chem. SOC. ( A ) 1971, 2720. A. W. Herlinger and T. L. Brown J . Amer. Chem. SOC. 1971,93 1790. 207 L. G. Marzilli P. A. Marzilli and J. Halpern J . Amer. Chem. SOC. 1971,93 1374. 2 0 8 G. Costa A. Puxeddu and E. Reisenhofer Chem. Comm. 1971 993 Transition-metal Carbonyl Organometallic and Related Complexes 445 and alkylcobalamines with electron-withdrawing P-groups undergo reversible depr~tonation~" to olefin complexes of Co'.Complexes of type (py)Co(dmg),-CH(Ar)CH,R rapidly insert oxygen into the cobalt-carbon bond giving peroxo-complexes.2 a-Halogenoalkylcobaloximes RCHXCo"'(dmg),(py) are reduced by borohydride in methanol to the corresponding RCH2 derivatives, without interchange with reagents R'CH,X (which could trap free Co'); the suggested mechanism is RCHXCo"' 5 RCHX-CO' + RCH:Co" 5 RCH2Co"' (the carbene may be formed as shown or directly by hydride attack at X).,ll However Co(sa1en) (presumably as Co') catalyses the borohydride reduction of CHC1 to CH,Cl ;,12 if cobalt-carbon bonds were not both made and broken, the reaction would not be catalytic whereas the above mechanism might have been expected to generate CH,Cl.Transfers of alkyl groups from one cobalt atom to another have been demon-strated under various conditions. Formal methyl radical transfer has been observed even in the dark between Co" and Co"' (distinguished by the nature of the chelating ligands attracted to each).,' The kinetics of the formal car-bonium ion transfer RCo"' + Co' -+ Co'+RCo"' have been investigated ; the reaction is first-order in each component with low energy and unfavourable entropy of activation consistent with a true SN2 mechanism at carbon. It is suggested214 that such a process rather than car-banion transfer from Co' to Co"' is responsible for the reaction215 dpnCo'Me + dpnCo"'Me -P dpnCo' + dpnCo"'Me, [dpnH = 1,3-bis(biacetylmono-oximeimino)propane] Interest in transfer of carbon ligands between cobalt and other metals continues, the subject having both synthetic and (when the acceptor metal is mercury) environmental significance.It has been shown that while methyl transfer from methylvitamin B, to Hg" or Tl"' is a nucleophilic displacement at methyl carbon transfer to Pt" requires the presence of Pt'" (the behaviour of Au'-Au"' mixtures is similar); it is suggested that Pt" must lose two electrons to PtIV at the same time as it accepts a methyl anion from cobalt.216 The ability 2 0 9 G. N. Schrauzer J . H. Weber and T. M. Beckham J . Amer. Chem. Soc. 1970 92, 7078. 2 1 0 K. N. V. Duong C. Fontaine C. Giannotti and A.Gaudemer Tetrahedron Letters, 1971 1187. M.-N. Ricroche C. Bied-Charreton and A. Gaudemer Tetrahedron Letters 1971, 2859. 2 1 2 I . Ya. Levitin M. Dvolaitzky and M. E. Vol'pin J. Organometallic Chem. 1971, 31 C37. 2 1 3 A. van den Bergen and B. 0. West Chem. Comm. 1971 52. 2 1 4 D. Doddand M. D. Johnson Chem. Comm. 1971 1371. 2 1 5 G. Costa G. Mestroni and C. Cocevar Chem. Comm. 1971 706. 2 1 6 G. Agnes S . Bendle H. A. 0. Hill F. R. Williams and R. J. P. Williams Chem. Comm., 1971 850 446 P. S. Braterman of alkylcobalt chelates to alkylate olefins in the presence of Pd" is ascribed to initial metal-metal alkyl transfer ; and indeed allylcobalt chelates give isolable palladium allyk2 Reaction between hydrated rhodium trichloride and 2-methylallyl alcohol gives a material characterized as its 4-methylpyridine adduct (44) ;,I8 ally1 alcohol however eliminates propene to give (45).,19 Azobenzene reacts with L Rh L .Cl\ I ,c1 CH -0 / \ Me CH,-C-CH,OH \ Me / i \CH,-C (44) L = 4-methylpyridine rhodium trichloride to give [(PhN N.C6H4-0-)2 RhC1] which with rhodium carbonyl chloride dimer gives (PhN NC6H4-o-)Rh(C1),Rh(CO) :220 the crystal structure of (PhN N.C6H4-o-),Rh0,CMe in which the acetate is bidentate, has been reported.These latter compounds react with CO to eliminate [PhN NC,H,],.22 Extensive ortho-insertion has also been demonstrated in a range of iridium-triaryl phosphite complexes,2 2 2 and the crystal structure of [(PhO),P.O.C6H4-o-],IrP(oPh),Cl has been reported.,, Insertion of Rh' {as [Rh(CO),CI],} into a cyclopropane ring (of PhC,H,) gives (46) but benzyl-cyclopropane gives (47) ; as expected bicyclo[4,1,0]heptane gives (48).224 The I I Rh(C0)CI Rh(C0)Cl 0 2 deuteriation of cyclo-octene by (Ph,P),RhCI unlike that of cyclohexene or oct- 1-ene is accompanied by extensive hydrogen exchange ; this is interpreted as a conformational strain effect in intermediate (49) which can therefore elimin-2 1 7 2 1 8 2 1 9 2 2 0 2 2 1 2 2 2 2 2 3 2 2 4 M.E. Vol'pin L. G. Volkova I. Ya. Levitin N. N. Boronina and A. M. Yurkevich, Chem. Comm. 1971,849. J. A. Evans D. R. Russell A. Bright and B. L. Shaw Chem. Comm. 1971,841. A. Bright J. F. Malone J. K. Nicholson J. Powell and B. L. Shaw Chem. Comm., 1971 712. M. I.Bruce B. L. Goodall M. Z. Iqbal and F. G. A. Stone Chem. Comm. 1971,661. A. R. M. Craik G. R. Knox P. L. Pauson R. J. Hoare and 0. S. Mills Chem. Comm., 1971 168. E. W. Ainscough S. D. Robinson and J. J. Levison J. Chem. SOC. ( A ) 1971 3413. J. M. Guss and R. Mason Chem. Comm. 1971 5 8 . K. G. Powell and F. J. McQuillin Chem. Comm. 1971 931 Transition-metal Carbonyl Organometallic and Related Complexes 447 ate (Ph,P),RhClD or (Ph,P),RhClHD as well as undergoing conversion into the expected [ 1,2-2H,]cyclo-octane.225 Complexes (Ph,P),Ni(aryl)(X) (X = C1 or Br) have been prepared by oxidative addition of aryl halides to tetrakis(tripheny1phosphine)nickel; the order of thermal stability is discussed.226 Reaction of nickelocene with 2-chloroazo-benzene gives (50) ; 2,2'-dichloroazobenzene gives (51).227 The relatively stable complexes trans-(Pr',P),NiMeX and (dppe)NiMe have been prepared using methyl-lithium.228 Me2Ni(PCx3) is obtainable from nickel bis(acety1aceton-ate) the phosphine and aluminium trimethyl; it reacts with nitrogen to give (Cx,P),Ni.NN.Ni(PCx,) but only in the presence of excess aluminium tri-Reaction of o-bromophenylnickelbis(tripheny1phosphine)chloride with lithium gives a material formulated as (52) on chemical and ebullioscopic evidence (in n-butane two triphenylphosphine ligands are reversibly lost).30 The complexes (CH,-o-C,H,.PPh,),M (M = Nil Pd or Pt) have been prepared.231 2 2 5 J. G. Atkinson and M. 0. Luke Cunad. J . Chem. 1970,48 3580. 2 2 6 M. Hidai T. Kashiwagi T. Ikeuchi and Y . Uchida J .Organometallic Chem. 1971, 30 279. 2 2 7 I . V. Barinov T. I. Voyevodskaya and Yu. A. Ustynyuk J . Organometallic Chem., 1971 30 C28. 2 2 8 M. L. H. Green and M. J. Smith J . Chem. SOC. ( A ) 1971 639. 2 2 9 P. W. Jolly K . Jonas C. Kriiger and Y.-H. Tsay J . Organometallic Chem. 1971, 33 109. 230 J. E. Dobson R. G. Miller and J. P. Wiggen J . Amer. Chem. SUC. 1971,93,554. 2 3 1 C. Longoni P. Chini F. Canziani and P. Fantucci Chem. Comm. 1971 470 448 P. S. Braterman The generality of the ortho-insertion reaction for palladium has been illustrated by the formation of complexes [Me,N.RCH-o-C,H4PdC1] (effective agents for the resolution of optically active p h ~ s p h i n e s ) ~ ~ ~ the aldoxime and ketoxime derivatives &(OH) C(R)-o-C,H,bdCl] ,233 the biacetylbis(N-methy1-N-pheny1)osazone derivative (53),234 and the 1,4-bis(aminoethyl)benzene deriva-tives (54a,b).235 Me Me Me\ N-N dN /Me Ph' Pd \ )y / Pdq Et NN\ 21 Et (544 \ /c1 \ > J W 2 Whereas o-tolylphosphine complexes of Pt" readily eliminate HX to give systems in which platinum is bonded to substituent carbon,236 the corresponding o-tolylphosphites eliminate ring ortho-hydrogen exclu~ively.~ 3 7 In bis(o-allyl-phenyl)platinum prepared by the Grignard route the ligands are bidentate, the double bond of the ally1 group being co-ordinated and the configuration (from dipole-moment evidence) is cis.HCl cleaves only the metal-ring bond whereas triphenylphosphine cleaves the metal-olefin bond. Carbon monoxide gives first (CH CH.CH,.C,H,-o-),Pt(Co) which rearranges to the carbonyl insertion product (CH f CH.CH,C,H4-o-CO-),~t.238 Substituted cyclopro-panes react with (PtCl,C,H4) to give specifically CH,-CHR-CH,.P%l (con-trast ref.224) ; electron-withdrawing groups R inhibit this reaction.239 2 3 2 S. Otsuka A. Nakamura T. Kano and K. Tani J . Amer. Chem. SOC. 1971,93,4301. 2 3 3 H. Onoue K. Minami and K . Nakagawa Bull. Chem. SOC. Japan 1970,43 3480. 2 3 4 G. Bombieri L. Caglioti L. Cattalini E. Forsellini F. Gasparrini R. Graziani and 2 3 5 S. Trofimenko J . Amer. Chem. SOC. 1971,93 1808. 2 3 6 A. J . Cheney B. E. Mann B. L. Shaw and R. M. Slade Chem. Comm. 1970 1176. 2 3 7 E. W. Ainscough and S. D. Robinson Chem. Comm. 1971 130. 2 3 8 2 3 9 K. G. Powell and F. J. McQuillin Tetrahedron Letters 1971 3313.P. A. Vigato Chem. Comm. 1971 1415. M. Aresta and R. S. Nyholm Chem. Comm. 1971 1459 Transition-metal Carbonyl Organometallic and Related Complexes 449 CH,CH,CH,PdCl,(py) rearranges thermally in solution to give (55).240 Oxidative addition of MeC(CN) to (Ph,P),Pt gives (Ph,P),Pt(CN)-C(Me)(CN) ; a rare example of metal insertion into an unstrained carbon-carbon bond.241 1 c1- Pt - c1 I PY ( 5 5 ) Polarographic reduction of the [Me,Pt(OH,),]+ cation takes place at un-usually high negative potentials for Pt'v;242 this is presumably owing to the high o-donor strength of methyl. The coupling between platinum and 13C in a range of methylplatinum(1r) complexes gives a measure of the trans influence of the opposing ligand and is proportional to the coupling to platinum of the methyl protons (confirming current interpretation^).^^^ The insertions of C2F4 CF,CiCCF, and CO into the platinum-carbon bond of complexes trans-Pt(X)(Me)L, and one or both of those of cis-Pt(Me),L, have been observed.Electron-releasing ligands L promote the reaction which thus in-volves co-ordination of the entering group as a crucial step244 (this co-ordination is regarded here as an oxidative addition) and indeed (Ph,P),Pt(Me),-(CF,C i CCF,) has been isolated.245 The kinetics of cis-trans isomerization in (Et,P),Pt(Cl)(o-tolyl) indicate cis-like and trans-like chloride-free intermediate^.,^^ The hydrolysis or alcoholysis of Pt" compounds of type BrCH2CHC6H4-o-PPh,PtBr,L gives the rearranged products e'H ,.CH(0R)-C6 H4-o-PPh Pt Br L ;247 similar rearrangements occur on methanolysis of related ligands bound to gold(111).~~~ Exchange between trimethylphosphine and its methylgold(r) complex is fast enough to follow by n.m.r.; the mechanism is associative and there is a sign difference in phosphorus-hydrogen coupling constant between free and bound ligand.Exchange in LAuMe is slow on the n.m.r. time-scale but may be accom-1 I 24" ( a ) R. D. Gillard M. Keeton R. Mason M. F. Pilbrow and D. R. Russell J . Organo-metallic Chem. 1971 33 247; (6) M. Keeton R. Mason and D. R. Russell ibid. p. 259. 2 4 1 J. L. Burmeister and L. M. Edwards J . Chem. Soc. ( A ) 1971 1663. 2 4 2 K. Kite and D. R. Rosseinsky Chem. Comm. 1971 205. 2 4 3 ( a ) M. H. Chisholm H. C. Clark L. E. Manzer and J.B. Stothers Chem. Comm., 2 4 4 H. C. Clark and R. J. Puddephatt Znorg. Chem. 1970,9 2670. 2 4 5 H. C. Clark and R. J. Puddephatt Znorg. Chem. 1971 10 18. 2 4 6 G. Faraone V. Ricevuto R. Romeo and M. Trozzi J . Chem. SOC. ( A ) 1971 1877. 2 4 7 2 4 8 1971 1627; (b) A. J. Cheney B. E. Mann and B. L. Shaw ibid. 1971 431. M. A. Bennett W. R. Kneen and R. S . Nyholm J. Organometallic Chem. 1971 26, 293. M. A. Bennett K. Hoskins W. R. Kneen R. S. Nyholm R. Mason P. B. Hitchcock, G. B. Robertson and A. D. C. Towl J . Amer. Chem. Soc. 1971,93,4592 450 P. S. Braterman plished over a day at 325 K.249 The vibrational spectra of complexes of type (Me2AuX) have been obtained;250 the wide range of ligands that stabilize the grouping Me2Au+ contrasts with what is known of Me2Pto.Species R’,R2AuL have been prepared by ligand cleavage of [R’,AuX] dimers followed by reaction with organolithium or organosodium compounds ; methyl has a trans-weakening influence and cyclopentadienyl is co-ordinated through one carbon only but shows time averaging of the ring protons by an intramolecular Vinyl and Related Complexes. Bis(n-cyclopentadienyl)zirconium(hydride)-(chloride) reacts with acetylenes to give the corresponding (vinyl)(chloride) by Zr-H addition across the acetylenic bond. The dihydride reacts similarly, giving the bis(trans-alkenyl) complexes with monosubstituted acetylenes ; but with diphenylacetylene (56) is formed.252 The complex CH i CCH,.Mn(CO),-PPh3 (from prop-2-ynyl chloride and the metal anion) reacts with acetic acid Ph 3$ Ph Zr = Zr / \ ( 5 6 ) (n-C5H 5 ) (n-C 5 H 5 ) to give MeCOOCH,C( CH,)Mn(CO),PPh3 and with SO to give &H2-0S(0)-CH CMn(CO),PPh3 ; with methyl- or phenyl-pentacarbonylman-ganese prop-2-ynyl alcohol gives C(CH,OH) CHC(R)OMn(CO) .2 5 3 Ph,P-C,H,-o-Rh(PPh,) reacts with diphenylacetylene to give (57).254 Isomeriz-ation of the a-2-methylallyl ligand to a-2-methyl-1-propenyl by HCl has been observed (as has base-reversible addition of HC1 to o-allyl giving chloro-p r ~ p e n y l ) . ~ ~ trans-(Trichlorovinyl)(phenylethynyl)nickel bis(trimethy1phos-Ph z 4 y ( a ) A. Shiotani H.-F. Klein and 1555; (6) H. Schmidbaur and A. (57) H. Schmidbaur J . Amer. Chem. SOC. 1971 93, Shiotani Chern. Ber. 1971 104 2821; ( c ) H. Schmidbaur A. Shiotani and H.-F.Klein ibid. p. 2831. ’ W. M. Scovell G . C . Stocco and R. S. Tobias Innrg. Chem. 1970,9,2682. 2 5 ‘ S. W. Krauhs G. C . Stocco and R. S. Tobias Inorg. Chem. 1971 10 1365. ’” P. C. Wades H. Weigold and A. P. Bell J . Organometallic Chem. 1971 21 373. 2 5 3 W. D. Bannister B. L. Booth R. N. Haszeldine and P. L. Loader J . Chem. SOC. ( A ) , 1971 930. 2 5 4 J. S. Ricci and J . A. Ibers J . Organometallic Chem. 1971 27 261. 2 s 5 A. J. Deeming B. L. Shaw and R. E. Stainbank J . Chem. SOC. ( A ) 1971 374 Transition-metal Carbonyl Organometallic and Related Complexes 45 1 phine) inserts benzyne generated in situ into the metal-ethynyl bond giving o-(PhC i C)C6H4Ni(C,C13)(PEt3)2 .256 Bis(benzonitri1e)palladium dichloride reacts with ClHgCH CHCl to give insoluble polymeric ClPdCH CHCl.Bis(dibenzy1ideneacetone)palladium reacts with electronegative acetylenes (such as Me0,C.C i C.CO,Me) to give metallacyclopentadienes.25 * The suggestion that the palladium-acetate-catalysed vinylation of arenes proceeds via vinylpalladium complexes receives support from the observation that bis(viny1)palladium does in fact vinylate ben~ene."~ Alkynyl Complexes. Complexes of type [RCiC.M(CO),]- (M = Cr Mo or W) have been prepared by photochemical substitution reactions.260 The compound Ph,PCCMn(CO),Br has been found to have a phosphorus-carbon-carbon angle of 165" and a carboy-carbon distance of 120 pm and is therefore formulated as a complex of Ph,PC i c.261 Alkynyl complexes RC i CM(CO)(PPh,), (M = Rh or Ir ; n = 2 or 3) are prepared by reaction between the alkyne and the metal hydride (presumably by oxidative addition followed by hydrogen elimination).262 The carbon-carbon stretching frequency in complexes trans-(Ph,P),M(C i CR) (M = Ni Pd or Pt) varies with the Taft polar constant for R, which affects the amount of b a ~ k - b o n d i n g .~ ~ ~ Acyl and Acyloxy-complexes. The dimensions of Me,Nf [(n-C,H,)Mn(CO),-COPh] - indicate that the acyl ligand here has some carbene-like character.264 The decarbonylation of MeCOCO.Mn(CO) is too slow for pyruvoyl complexes to be intermediates in the reaction of MeCOMn(CO) with nucleophiles ; thus the latter reaction does not involve acetyl migration in the same way that the reactions of MeMn(CO) involve methyl migration.265 Reaction of (Ph,P),RuHCl with aldehydes gives products RCO.Ru(C0)-(Cl)(PPh,) in which RCO is formulated as a n-acyl group on both physical and chemical grounds [v(CO) = 1510 cm-' ; the lack of reactivity suggests octa-hedral ~ o - o r d i n a t i o n ] .~ ~ ~ Mono- and di-fluoroacetyltricarbonylcobalt phosphine compounds have been prepared from the complex metal anion and the acid anhydride; two bands are found for the acyl stretch in THF below room temperature.267 A range of cobalt(Ir1) acyls of macroscopic ligands have been prepared ; the acyl CO stretch-2 5 6 R. G. Miller and D. P. Kuhlman J . Organometallic Chem. 1971,26,401. 2 5 7 0. L. Kaliya 0. N. Temkin R. M. Flid and L. G. Volkova Russ. J . Inorg. Chern., 2 5 8 K. Moseley and P. M. Maitlis Chem. Comm. 1971 1604. 2 5 9 I. Moritani Y.Fujiwara and S. Danno J . Organometallic Chem. 1971 27 279. 2 6 0 W. J. Schlientz and J. K. Ruff J . Chern. Sac. ( A ) 1971 1139. 2 6 1 S. Z. Goldberg E. N. Duesler and K. N. Raymond Chem. Comm. 1971 826. 2 6 2 ( a ) C. K. Brown and G. Wilkinson Chem. Cornm. 1971 70; (b) C. K. Brown D. 2 6 3 H. Masai K. Sonogashira and N. Hagihara J. Organornetallic Chem. 1971 26 271. 2 6 4 E. Hadicke and W. Hoppe Acta Cryst. 1971 B27 760. 2 6 5 C. P. Casey and C. A. Bunnell J . Amer. Chem. SOC. 1971,93,4077. 2 6 6 2 6 7 E. Lindner H. Stich K. Geibel and H. Kranz Chern. Ber. 1971 104 1524. 1970 15 1326. Georgiou and G. Wilkinson J . Chem. SOC. ( A ) 1971 3120. R. R. Hitch S. K . Gondal and C. T. Sears Chem. Comm. 1971,777 452 P. S. Braterman ing frequency is sensitive to the nature of the other ligand.268 Oxidative addition of benzyl halides to (71-C5H5)Rh(CO)PPh, giving benzylacyl complexes is first-order in each component.Addition of ally1 halides is superficially similar, but the first products are in fact o-ally1 carbonyls which only slowly rearrange to the final allylacyl compounds.269 By contrast both the addition of acyl halides to Ir(N,)(PPh,),C1270 (with loss of NJ and of alkyl halides to Fe(CO),-(PMe,) ,27 give acyl complexes (Ph,P)21r(COR)Cl and (Me,P)2Fe(C0)2-(COR)Cl which reorganize with (Fe) or without (Ir) loss of CO to the alkyls. The latter reorganization of a five-co-ordinate Ir"' acyl to a six-co-ordinate alkyl is a reversible process ; complexes L(OC)Ir(COR)Cl are indicated as inter-mediates from the kinetics and stereochemistry of the reaction of L(OC)Ir(CO)-(R)CI with L' to give LL(OC)Ir(COR)Cl .272 The kinetics and solvent depen-dence of the reaction of (Ph,As)Pt(CO)(Cl)Et with Ph,As to give (P~,As)~-Pt(Cl)(COEt) indicate a three-co-ordinate intermediate (Ph,A~)Pt(cl)(cOEt).~~~ The product from nickel carbonyl and o-phenylene iodide formerly claimed as a benzyne complex has the structure (58).274 0 bqJ*, (58) Reaction of (Ph,P),Pt(N,) with carbon monoxide in a range of alcohols ROH gives (Ph3P),Pt(NCO)(C02R).275 Both forward and back reactions in the equilibrium (Ph,P),Pt(CO)Cl+ + ROH (Ph,P),Pt(COOR)Cl + H+ are first-order in each reagent.276 Fluoroalkyl and Related Complexes.A review has appeared on polyfluoro-aromatic derivatives of metals and metalloids.277 2 6 8 J .Booth P. J. Craig B. Dobbs J. M. Pratt G. L. P. Randall and A. G. Williams, 269 A. J. Hart-Davis and W. A. G. Graham Inorg. Chem. 1971 10 1653. 2 7 0 ( a ) M. Kubota and D . M. Blake J . Amer. Chem. SOC. 1971,93 1368; ( b ) M. Kubota, J . Chem. SOC. ( A ) 1971 1964. D. M. Blake and S. A. Smith Znorg. Chem. 1971 10 1430. M. Pankowski and M. Bigorgne J. Organometallic Chem. 1971,30 227. 2 7 2 R. W. Glyde and R. J. Mawby Inorg. Chim. Acta 1971 5 317. 2 7 3 R. W. Glyde and R. J. Mawby Znorg. Chem. 1971,10 854. 2 7 4 N. A. Bailey S. E. Hull R. W. Jotham and S. F. A. Kettle Chem. Comm. 1971, 2 7 s W. Beck M. Bauder G. La Monica S. Cenini and R. Ugo J . Chem. SOC. (A) 1971, 2 7 6 J. E. Byrd and J. Halpern J. Amer. Chem. SOC. 1971 93 1634. 2 7 7 S.C. Cohen and A. G . Massey Adv. Fluorine Chem. 1971 6 83. 282. 113 Transition-metal Carbonyl Organometallic and Related Complexes 453 Reaction of the pentafluorophenyl Grignard reagent with anhydrous cobalt(1r) bromide in THF gives a material formulated as (C6F,),Co; this reacts with iodine to give C,F,I with acid to give C,F,H with oxygen to give a range of linear poly(perfluoropheny1) compounds (C,F,)(C,F,),(C,F,) (n = &3)? and with triphenylphosphine to give (Ph3P),CO(C,F& .278 The substituted cyclo-butadiene complex (M~,As)~R~(CO)CIC,(CF~)~ reacts in wet boiling benzene to give (59).279 The strong nucleophile [(Ph,P),Rh(CO),]- reacts with C,F,, AsMe I P 3 C1 1 C=CCF, \Rh’ I C,F,N etc. to give products (Ph,P),Rh(CO),(perfluoroaryl).280 The decom-position of (p-MeO.C,F,.CO,),Ni(phen) in boiling toluene (phen = o-phenan-throline) gives (p-Meo.C,F,),Ni(phen) ; this is a novel use of decarboxylation to prepare metal-carbon bonds.Products in which the perfluoroaryl group has substituted into phenanthroline are also found.28 trans-(Et,P),PtHCl elimin-ates HF with perfluorobutene to give (Et,P),Pt(Cl)C CFCF,-CF, which may -be hydrolysed to (Et,P),Pt(Cl)C CFCF CF.0.282 The behaviour of trifluoro-methylplatinum compounds with acetylenes is in interesting contrast to that of the methyl analogues (ref. 176). Thus trans-[Pt(CF,)(acetone)(PMe,Ph),]+ PF,-reacts with but-2-yne in methylene chloride to give the tetramethylcyclobutadiene complex [Pt(CF,)(C,Me,)(PMe,Ph),]+. [(Me,PhP),Pt(CH3),CF3]+ reacts with CH ICCH,CH,OH to give [(Me,PhP),Me,Pt(CF,) C.0CH2CH2CH2]+ 7 $hCF* I (60) the first carbene complex of a metal in an oxidation state greater than C,F5Ag may be prepared from C,F,Li and CF,CO,Ag or from C,F,Br and 2 7 n C.F. Smith and C. Tamborski J . Organometallic Chem. 1971 32 257. 2 7 9 J. T. Mague J . Amer. Chem. SOC. 1971,93 3550. 2 8 0 B. L. Booth R. N. Haszeldine and I. Perkins J . Chem. SOC. ( A ) 1971,927. P. G. Cookson and G. B. Deacon J . Organometallic Chem. 1971 33 C38. 2 8 2 W. J. Cherwinski and H. C. Clark J . Organometallic Chem. 1971 29 451. 2 8 3 M. H. Chisholm and H. C. Clark Chem. Comm. 1971 1484 454 P. S . Braterman (CF,),CFAg ; it acts as a pentafluorophenylating agent in reactions with halides of copper zinc mercury trimethylsilyl and Insertion reactions of unsaturated fluorocarbons continue to arouse interest.Thus whereas h4-cyclo-C4Me4Fe(CO) reacts photochemically with hexa-fluoroacetone to give (C4Me4)(OC),F&C(CF,),6 C,F gives (60) ; 285 allyl-cobalt tricarbonyl reacts with C,F to give CH,kHCH2CF,CF,ko(C0) .286 Both these reactions may be regarded as insertion of C2F4 into one of the metal-carbon bonds of a polyhapto-ligand. (n-C,H,)Ru(PPh,),H reacts with an excess of hexafluorobut-2-yne to give not only (z-C,H,)Ru(PPh,),-C(CF,) C(CF3)H but also (n-C,H,)Ru(PPh,).C(CF,) C(CF,)C(CF,) C(CF3)H and Ph,P.C(CF,): C(CF,)C(CF,) C(CF3). These products are consistent with repeated C,F, insertion into metal-ligand bonds but (n-C,H,)Ru(PPh,),C(C02Me) -C(C0,Me)H reacts with C4F6 to give (61). It is suggested that the reactions may involve nucleophilic attack by C4F6 on an ionic species of type M(H)-C(R):-C.R in equilibrium with M-C(R) :CHR.287 I I +-H CF3 (61) Reaction of acetylacetonatorhodium 1,5-cyclo-octadiene with four moles of hexafluorobut-2-yne involves 1,4-addition to the acetylacetonato-ligand as well as displacement of the diene to give (62).288 The structure of (Ph3P),-ki.C(CF,),.O has been confirmed crystallographically ; the nickel-carbon and nickel-oxygen distances are similar (187 and 189 pm respectively) and the carbon-oxygen distance is 132 pm.289 The photochemical reaction of Ph,PAuMe with 2 8 4 2 8 5 2 8 6 2 8 7 2 8 8 2 8 9 C=O I Me (62) K.K. Sun and W. T. Miller J. Amer. Chem. SOC. 1970 92 6985. A. Bond and M.Green Chem. Comm. 1971 12. A. Greco M. Green and F. G. A. Stone J. Chem. SOC. ( A ) 1971 3476. T. Blackmore M. I. Bruce F. G. A. Stone R. E. Davis and A. Garza Chem. Comm., 1971 852. D. M. Barlex J. A. Evans R. D. W. Kernmitt and D. R. Russell Chem. Comm. 1971, 331. R. Countryman and B. R. Penfold Chem. Comm. 1971 1598 Transition-metal Carbonyl Organometallic and Related Complexes 455 hexafluorobut-2-yne gives the 1,2-dimetalloalkene cis-Ph,PAuC(CF,) C(CF,)-AuPPh .290 Miscellaneous. Bis-(1,2-carborane) HCB1oHloC-CBloH,oCH (H,bcb) reacts with butyl-lithium to give Li,bcb a convenient precursor for the air- and water-stable complexes [Cot'( bcb),] - [Co"'(bcb),] - [Ni"(bc b),I2 - [Nit''( bcb),] - , [Cu"(bcb),12- [Cu"'(b~b)~]- and [ Z n ( b ~ b ) ] ~ - .~ ~ ' Reaction of azides of pal-ladium platinum gold and mercury with isonitriles gives complexes of the tetrazolate [C CN-N N.N(R)] (tz) grouping ; prepared in this way are species (Ph,P)(RNC)Pd(tz) and the platinum analogue (MeNC)Au(tz) [Au(tz)J, [Au(tz)J'- and H g ( t ~ ) . ~ ~ , -Rearrangements via Presumed Organometallic Intermediates. Platinum metal is ineffective and organoplatinum hydrides are presumably implicated in the PtCI, - catalysed exchange of the hydrogen of saturated alkanes with deuterium in acidified D20.293 There has been a remarkable upsurge of interest in the mechanism of Woodward-Hoffmann-forbidden and other slow rearrangements of strained hydrocarbons catalysed by transition-metal cations and there is agreement (compare ref. 239) that a degree of electrophilic attack by metal on strained carbon-carbon bonds is involved.Thus electron-donating substituents facilitate the silver(1)-catalysed rearrangement of cubane to ~uneane.~" The addition of the strained hydrocarbon to the metal is a discrete rate-determining step rather than part of a truly concerted electrocyclic process ; thus the rates of such re-arrangements can be insensitive to the steric effects of substituent confor-m a t i ~ n ~ ~ and the kinetics of the AgI-catalysed rearrangement of bicyclobutanes to butadienes indicate the reversible formation of a complex between silver and the starting ma terial., The rearrangement pathway is sensitive to the nature of the catalysing metal. In general the requirements for rearrangement at Ag' are more stringent than those for rearrangement at Rh'; this accords with the formation of three-centre C,Ag bonds in the former case and complete insertion of Rh between two carbon atoms in the latter.297 In some cases changing the metal causes gross differences ; thus cubane rearranges to cuneane at Ag' or Pd" but to tricyclo[4,2,0,02~5]octa-diene at Rh' ; this last reaction may possibly involve homolysis of metal-carbon bonds.298 Dimethylbicyclobutanes [(63) and conformers] are isomerized by Ag' to hexa- 1,3-dienes the stereochemistry at the double bonds being related 290 C.J. Gilmore and P. Woodward Chem. Comm. 1971 1233. 2 9 1 D. A. Owen and M. F. Hawthorne J . Amer. Chem. SOC. 1971,93 873. 2 9 2 W. Beck K. Burger and W. P. Fehlhammer Chem. Ber. 1971 104 1816.2 9 3 ( a ) R. J. Hodges D. E. Webster and P. B. Wells Chem. Comm. 1971 462; (b) R. J. Hodges D. E. Webster and P. B. Wells J . Chem. SOC. ( A ) 1971,3230. 2 9 4 G. F. Koser Chem. Comm. 1971 388. 29s L. A. Paquette R. S. Beckley and T. McCreadie Tetrahedron Letters 1971 775. 2 y 6 L. A. Paquette S. E. Wilson and R. P. Henzel J . Amer. Chem. SOC. 1971 93 1288. 2 9 7 J. Wristers L. Brener and R. Pettit J . Amer. Chem. SOC. 1970 92 7499. 2 9 8 J. E. Byrd L. Cassar P. E. Eaton and J. Halpern Chem. Comm. 1971 40 456 P. S . Braterman to the conformation (em or endo) of the original methyl groups ; but (PhCN),-PdCl, [Rh(CO),Cl] CuCl and HgBr all give a mixture of dienes including 2-methylbuta- 1,3-diene7 which could only be formed by hydrogen migration.299 MewMe (63) One suggested general mechanism is collapse of two bonds at bridgehead carbon to give a carbene which is metal-stabilized (this part of the reaction being a reversal of the addition of carbenes to alkenes);300 however differences exist between the rearrangement products of the bicyclobutanes and those of diazo-compounds which are more certain precursors of the suggested carbene inter-mediate,301 and reaction schemes involving carbonium ion intermediates are now widely referr red.^',-^'^ A particularly elegant study consistent with some form of carbonium ion intermediate concerns the cycloaddition of benzyne to cyclopolyenes as modified by the presence of silver ion (Scheme 3).It is sug-gested that the C6H4Ag+ ion adds as an electrophile to ring systems to give -Ag+ - -b \ / Scheme 3 o-argentophenyl-cyclo-polyenyl cations.The products are then determined by attack of the highly electron-deficient terminal carbon atom of the polyenyl system on the aryl-silver o-bond and by the presence or absence of a Woodward-Hoffmann allowed bicyclization of the cyclopolyenyl cation. The next step in the reaction extrusion of Ag+ with formation of a carbon-carbon bond is 2 9 9 M. Sakai H. Yamaguchi and S. Masamune Chem. Comm. 1971 486. 3 0 0 P. G. Gassman T. 3. Atkins and F. J. Williams J . Amer. Chem. SOC. 1971 93 1812. 3 0 1 M. Sakai and S. Masamune J . Amer. Chem. SOC. 1971 93,4610. M. Sakai H. H. Westberg H. Yamaguchi and S. Masamune J . Arner. Chem. SOC., 1971,93,4611. 3 0 3 L. A. Paquette R. P. Henzel and S. E.Wilson J . Arner. Chern. SOC. 1971 93 2335. ' 0 4 P. G. Gassman and T. J. Atkins J . Amer. Chem. SOC. 1971,93,4597. 3 0 Transition-metal Carbonyl Organometallic and Related Complexes 457 formally the reverse of carbonium ion formation in the rearrangements discussed above.305 If not perhaps at Ag' then certainly at other metals a formally simple reaction can conceal mechanistic complexity. Thus the rearrangement of specifically deuteriated bicyclo[2,1,0]pentane to cyclopentene is catalysed by [Rh(CO)2C1]2 with statistical randomization of the deuterium positions ; randomization must precede rearrangement as this rhodium complex does not cause deuterium migration in labelled ~yclopentene.~'~ The mechanism of olefin dismutation has aroused controversy. In one proposed mechanism ligand electrons flow into vacant metal d, orbitals (the olefins are visualized as lying in a plane above the xy plane of the metal) while the elec-trons of full d, orbitals are donated to form new carbon+arbon bonds.307 This suggestion has been criticized on the grounds that it involves formation of an intermediate cyclobutane-metal complex that should give rise to detectable cyclobutane production (none is found in the dismutation of C2H4 + C2D4 to C2H2D,) and an alternative scheme is proposed in which both c- and n-bonds of the reagents lose their identity in the catalytic ~ ~ m p l e ~ e ~ ~ ' ~ ~ Other workers have argued further that mechanisms in which the metal is excited must not be precluded and may even play an important part in catalyst regeneration.308b The Cleavage of Metal-Carbon o-Bonds.(See also refs. 213-216). An earlier orthodoxy309 assumed that such bonds were inherently labile in the absence of certain special factors. This position is now less tenable (see e.g. ref. 153) and the study of the kinetics and mechanism of cleavage seems destined for rapid growth. The stereochemistry of the reactions of the previous section shows that in many cases carbon-metal bond cleavage as well as bond formation is a highly specific process. Homolytic mechanisms are most prominent early in the transition series, or where cleavage is photochemical rather than thermal ; this result is as expected on general gro~nds.~" Thus photoexcitation of the ring j K* transition in methylcobalamine causes homolytic cleavage of the cobalt-methyl bond,31 and the reaction of ref.290 (page 455) appears to involve photohomolysis of a gold-methyl bond. The thermolysis of compounds of type (n-C5HJ2Ti(R)C1 obeys an Arrhenius law and for R = PhCH2CH2 it is established that there is no break in the Arrhenius plot on melting. The products are those of disproportionation if R has a /?-hydrogen hydrogen abstraction if R has one a-hydrogen but no P-hydrogen and in other cases those of ligand combination. It is inferred that the 30s ' 0 6 P. G. Gassman T. J . Atkins and J . T. Lumb Tetrahedron Letters 1971 1643. 3 0 7 (a) F. D. Mango Tetrahedron Letters 1971 5 0 5 ; (6) F. D. Mango and J . H. Schachtschneider J . Amer. Chem. SOC. 1971 93 1123. 3 0 8 (a) G. S. Lewandos and R. Pettit Tetrahedron Letters 1971,789; (6) G.L. Caldow and R. A. MacGregor J . Chem. SOC. ( A ) 1971 1654. 3 0 9 ( a ) J. Chatt and B. L. Shaw J . Chem. SOC. 1959 705; ibid 1960 1718; (b) M. L. H. Green 'Organometallic Compounds,' Methuen London 1968 Vol. 2 pp. 22G224. 3 1 0 P. S. Braterman and R. J. Cross J.C.S. Dalton 1972 657. 3 1 1 J. M. Pratt and B. R. D. Whitear J . Chem. SOC. ( A ) 1971 252. L. A. Paquette Chem. Comm. 1971 1076 458 P . S . Braterman rate-determining step in the decomposition is unimolecular and probably involves formation of R- radicals still held in the metal co-ordination ~ p h e r e . ~ l 2 From analysis of the fragments generated from Grignard reagents and CrCl,(THF) it is concluded that the chromium-carbon bonds formed may decay either by homolytic cleavage or by metal hydride Electrophilic attack at co-ordinated carbon (compare ref.216) is implicated in the bimolecular displacements of [Mn(CO),] + and more rapidly of [(n-C,H,)-Fe(CO),]+ from their pyridylmethyl derivatives by Hg" and Tl"' in water.314 Bromolysis of Bu'CHDCHD-Fe(CO),(n-C,H,) gives Bu'CHD-CDHBr ; i.e. in this case bromolysis occurs with inversion. This is of some importance, not only because it excludes a radical mechanism but also3 because the claim3 l 6 to have established retention in oxidative addition of Ir' depended on the assump-tion that bromolysis of metalkarbon bonds invariably occurred with retention. The stability to thermolysis of compounds (n-C,H,)Ni(PPh,)R falls along the series R = Me > Et > longer-chain groups.More surprisingly the isopropyl derivative is more stable than that of n-propyl and that of s-butyl is more stable than those of n- or iso-butyl. The methyl compound evolves methane and some ethane and this is attributed to homolysis but the product analysis from the longer-chain derivatives indicates p-elimination as the preferred decomposition p a t h ~ a y . ~ l 7 The thermolysis of compounds R,Ni(bipy) has been studied. The ethyl compound evolves butane on decomposition ; the n-propyl compound gives propane and propene. Co-ordination of alkene greatly facilitates the decomp~sition,~ l 8 causing a fall in apparent activation energy from 280 to 65 kJ mol- '. The reductive cleavage of organopalladium bonds by BH,- occurs with retention of configuration and is therefore not a free-radical rea~tion.~ l 9 Stereo-specific p-elimination of palladium acetate is implicated in the Pd"-catalysed acetoxy exchange between vinyl acetates and C-deuteriated acetic acid ; ex-change is sterically hindered by substituents and always occurs with cis-trans isomerization as required by Scheme 4.320 Scheme 4 3 L 2 J.A. Waters V. V. Vickroy and G. A. Mortimer J. Organometallic Chem. 1971 33, 41. R. P. A. Sneeden and H. H. Zeiss J. Organometallic Chem. 1971 26 101. Johnson and N. Winterton J. Chem. SOC. ( A ) 1971 910. G. M. Whitesides and D. J. Boschetto J. Amer. Chem. SOC. 1971 93 1529. R. G. Pearson and W. R. Muir J. Amer. Chem. SOC. 1970,92 5519. 3 1 4 ( a ) D . Dodd and M. D. Johnson J. Chem. SOC. ( B ) 1971 662; (6) D.Dodd M. D . 3 1 s 3 1 6 3 1 7 J. Thomson and M. C. Baird Canad. J. Chem. 1970,48 3443. 3 1 8 T. Yamamoto A. Yamamoto and S. Ikeda J. Amer. Chem. SOC. 1971,93 3350. 3 1 9 E. Vedejs and M . F. Salomon J. Amer. Chem. SOC. 1970 92 6965. 3 2 0 P. M. Henry J. Amer. Chem. SOC. 1971 93 3853 Transition-metal Carbonyl Organometallic and Related Complexes 459 Both the thermolysis of cis- and trans-prop-1-enylcopper (or their tributyl-phosphine adducts) to give hexa-2,4-dienes and that of but-2-en-2-ylcopper, occur with retention of configuration although free-radical (tributylstannane) reduction of but-2-en-2-yl bromide involves loss of c~nfiguration.~~' The decomposition of silver alkyls involves alkyl coupling but not disproportionation ; thus here again radical intermediates can be excluded as they can on other evidence in the decomposition of copper alkyls in which disproportionation is the only observed reaction.The curious fact that copper ethyl with n-propyl-copper gives ethane and propene but with isopropylcopper gives ethylene and propane is difficult to reconcile with a sequence (i) D-elimination of alkene giving copper hydride ; (ii) reduction of copper alkyl by copper hydride giving alkane. The isopropyl compound should eliminate propene preferentially. Thus alkyl disproportionation within di- or poly-nuclear species is indicated.,,, Such polynuclear species have been observed directly for m-trifluoromethyl-phenylcopper an octamer which evolves two successive moles of the diary1 to give the tetra-aryloctacopper cluster compound.The failure to obtain tri-fluoromethylbenzene like the failure of decomposing pentafluorophenyl copper tetramer to yield C6F,H demonstrates that non-radical pathways are responsible for decomposition in this case also.,,, Two-carbon Ligands.-Reviews have appeared on mono-olefin and acetylene complexes of nickel palladium and platinum;324 on optical activity of co-ordinated prochiral olefins ;325 and on addition-elimination reactions of pal-ladium compounds with ole fin^.,^^ The binding energy of carbon 1s in complexes (Ph,P),Pt(alkene) and (Ph,P),Pt(alkyne) is 283.2 eV indicating greater electron density at carbon than for the free ligands (284.9 eV) or their PtC1 complexes (284.2 eV).327 Relatedly, the order of Pt 4f binding energies (and thus presumably of positive charge on platinum) is (Ph,P),Pt < (Ph,P),Pt(diphenylacetylene) < (Ph,P),Pt(C,H,) < (Ph,P),Pt(CS,) < (Ph,P),PtO < (Ph,P),PtCl .328 Alkene Complexes.The tetramethoxyethylene (tme) complexes Fe(CO),(tme) and (n-CSHs)Mn(CO),(tme) have been prepared ; the CO stretching frequencies are higher than in the analogous ethylene complexes.329 Iron carbonyl derivatives of prochiral olefins have been prepared and resolved and the c.d. spectra related to absolute c~nfiguration.~~' The structures have been determined of (acac)-3 2 1 G. M. Whitesides C. P. Casey and J. K. Krieger J . Amer. Chem. Soc. 1971,93 137. 3 2 2 3 2 3 ( a ) A. Cairncross and W. A. Sheppard J . Amer. Chem. SOC. 1971 93 247; ( b ) A. 3 2 4 J . H. Nelson and H. B. Jonassen Co-ordination Chem.Rev. 1971 6 27. 325 G. Paiaro Orgunometallic Chem. Rev. 1970 A6 319. 3 2 b 3 2 7 D. T. Clark D. B. Adams and D. Briggs Chem. Comm. 1971,602. 3 2 8 C. D. Cook K. Y. Wan U. Gelius K. Hamrin G. Johansson E. Olsson H. Siegbahn, C. Nordling and K. Siegbahn J . Amer. Chem. Soc. 1971 93 1904. 3 2 9 M. Herberhold and H. Brabetz Z . Nuturforsch. 1971 26b 656. 3 3 0 A. Musco R. Palumbo and G. Paiaro Znorg. Chim. Actu 1971 5 157. M. Tamura and J. Kochi J . Amer. Chem. SOC. 1971,93 1483 1485. Cairncross H. Omura and W. A. Sheppard ibid. p. 248. R. F. Heck Fortschr. Chem. Forsch. 1971 16 221 460 P. S . Braterman Rh(C,H,) (in which the rhodium+arbon distance is 213 pm) and (acac)Rh-(C,H,)(C,F,) (in which rhodium-ethylene carbon is 219 pm and rhodium-tetra-fluoroethylene carbon is 201 Several groups of workers have described cationic olefin complexes of Rh'.Thus treatment of cyclo-octadiene or norborna-diene complexes of type (diolefin)Rh(acac) with triphenylmethyl fluoroborate in the presence of excess diolefin gives species [(diolefin),Rh]+. These may be con-verted by phosphine ligands for example into species [(diolefin)RhL,] +, [(diolefin)RhL,]+ or [RhL,] + depending on the ligands and conditions used; the behaviour of iridium is generally similar.332 The highly unsaturated species [M-(diolefin)] + (M = Rh or Ir) may be prepared from [M(diolefin)Cl] and AgPF6 in THF (species [(h3-allyl) Pd] + may be prepared similarly) ; these co-ordinate a r e n e ~ . ~ trans-(PhMe,P),Ir(CO)Cl reacts with ethylene in methanol in the presence of sodium tetraphenylborate to give [(PhMe,P),Ir(CO)(C,H,),] + ; both ethylenes may be replaced by 2,3-dimethylbuta-l,3-diene or by a single molecule of diphenyla~etylene.~~~ Weak complexing of lower olefins to the fifth position of Rh' in neutral Rh(acac)(CO) has been detected by incorporating the Rh' complex in the liquid phase of a g.1.c.column; the use of an optically active ligand at Rh' gives a system capable in principle of resolving optically active olefins. The crystal structure of the cyclo-octa-1 S-diene complex (PhMe,P),(cod)IrMe con-f i r m ~ ~ ~ ~ the structure (64) inferred from the limiting low-temperature n.m.r. Me Ir -PMe2Ph PhMe2P I (64) spectrum. At higher temperatures the signals from the chemically non-equivalent vinyl protons are averaged but those of the magnetically non-equivalent P-bonded methyl groups remain distinct ; this imposes constraints on the assign-ment of a detailed mechanism.33 The behaviour of (PhMe,P),Rh(norborna-diene)Me is generally similar but in (Ph,MeP),Rh(norbornadiene)Me and in the cod analogues even with PhMe,P as ligand intermolecular exchange of phos-phines occurs without loss of the distinction between the two types of vinyl pro ton.3 3 1 3 3 2 J. A. Evans and D. R. Russell Chem. Comm. 1971 197. ( a ) B. F. G . Johnson J. Lewis and D. A. White J . Chem. SOC. ( A ) 1971 2699; ( 6 ) M. Green T. A. Kuc and S. H. Taylor ibid. 1971 2334; ( c ) R. R. Schrock and J . A. Osborn J . Amer. Chem. SOC. 1971 93 2397. 3 3 3 R. R. Schrock and J.A. Osborn J . Amer. Chem. SOC. 1971,93,3089. 334 A. J. Deeming and B. L. Shaw J . Chem. SOC. ( A ) 1971 376. 335 V. Schurig and E. Gil-Av. Chem. Comm. 1971 650. 3 3 6 M. R. Churchill and S. A. Bezman J . Organometallic Chem. 1971 31 C43. 3 3 7 J. R. Shapley and J. A. Osborn J . Amer. Chem. SOC. 1970,92,6976. 3 3 8 D. P. Rice and J. A. Osborn J . Organometallic Chem. 1971,30 C84 Transition-metal Carbonyl Organometallic and Related Complexes 46 1 In the 1,2-dimethylcycloprop-l-ene complex CH,-CMe CMePt(PPh,) the angles at the co-ordinated carbon atoms and the large distance (150 pm) between them indicate loss of double-bond character on co-~rdination.~ 39 Semi-empirical calculations on Zeise's anion including electron4ectron repulsion terms lead to a carbon-carbon bond order of CQ.1.5. The trans-influence of the co-ordinated olefin is attributed to a predominance of n-labilizing over a-stabilizing effects.340 The weak a-trans influence is no doubt responsible for the high acidity of species [trans-Pt(OH2)(NH,),(alkene)] +,341 whereas the overall size of the trans influence manifests itself in the n.q.r. spectra of Zeise's salt and its bromine analogue.342 The i.r. spectra of species [PtCl,(olefin)] , where the olefin is a vinyl alcohol or ether show the effects of conjugation of the oxygen lone pairs to the double bond despite co-ordination. The metal-olefin frequencies indicate that co-ordination is weaker to palladium than to platinum.343 The exchange between (acac)Pt(C2H4)C1 and free ethylene has been followed by n.m.r.; it is first-order in each component with a negative entropy of activation and no solvent dependence ; a five-co-ordinate intermediate is indicated.344 The copper(1) chloride complexes of Me,SiCH CH2 and other Group IV vinyls are much more stable than the corresponding hydrocarbon olefin com-plexes ; an effect attributed to conjugation between the ligand n*-acceptor orbitals and vacant d-orbitals on the metalloid.345 Exchange between free and olefin-co-ordinated Ag' is fast on the n.m.r.time-scale down to 220 K ; the equilibrium constants depend on olefin and solvent but not greatly on temperature.346 The dissociation pressures of the solid fluoro- and chloro-ethylene complexes of AgBF show them to be much less stable than those of pr~pene.~,' Treatment of MeOCH,CH,HgCI with the powerful acid FS0,H-SbF,-S02 removes the methoxy-group as MeOH + leaving [(h2-C2H4)Hg1'l2 + charac-terized by n.m.r.Similarly 1-hydroxy-2-acetoxymercurinorbornane gives the Hg2 '-norbornene comple~."~ Alkyne Complexes. Whereas co-irradiation of Fe(CO) and ethylene in an argon matrix gives the known Fe(CO),C,H, the related reaction with acetylene gives a product assigned from its i.r. spectrum as the alkyne complex (OC),Fe-HC i CCH CH .349 Such stannyl-p-acetylene cobalt carbonyl complexes as 3 3 9 J. P. Visser A. J. Schipperijn J. Lukas D. Bright and J. J. de Boer Chem. Comm., 1971 1266. 340 H. Kato Bull. Chem. Soc. Japan 1971,44 348. 3 4 1 M. I. Gel'fman N. M. Karpinskaya and V. V. Kazumovskii Russ. J . Inorg. Chem., 1970 15 1438.3 4 2 (a) J. P. Yesinowski and T. L. Brown Inorg. Chem 1971,10 1097; (b) J. P. Yesinowski and T. L. Brown J . Mol. Structure 1971 9 474. 3 4 3 Y . Wakatsuki S. Nozakura and S. Murahashi Bull. Chem. Soc. Japan 1971,44 786. 344 C . E. Holloway and J. Fogelman Canad. J . Chem. 1970 48 3802. 345 J. W. Fitch D. P. Flores and J. E. George J . Organometallic Chem. 1971 29 263. 346 J. Solodar and J. P. Petrovich Inorg. Chem. 1971 10 395. 3 4 7 H. W. Quinn and R. L. VanGilder Canad. J . Chem. 1971 49 1323. 348 G. A. Olah and P. R. Clifford J . Amer. Chem. Sac. 1971 93 1261. 349 M. J. Newlands and J. F. Ogilvie Canad. J . Chem. 1971 49 343 462 P . S. Braterman [Co(CO),],Me,SnC i CH react with acetyl chloride-aluminium trichloride to give [Co(CO),],MeCOC i CH etc.," The complexes (Ph,P),PtCEC(CH,) and (Ph,P),PtC-C(CH,) in which the otherwise unknown cyclic acetylenes cycloheptyne and cyclohexyne are complexed to platinum have been prepared.Their stability is ascribed to the fact that complexation makes possible small CH -C-C angles (around la") thus relieving strain in the rings.351 Complexes (Ph,P),Pt(RIC i CR2) add HX (X = C1 or 02CCF3) to give trans-(Ph,P),Pt(X)(CR' CR2H) ; platinum and added hydrogen are mutually cis with respect to the vinyl double bond and in the HCCPh complex the hydrogen adds preferentially to the unsubstituted carbon.352 The but-2-yne complex is converted quantitatively into (Ph,P),PtX and a mixture of cis- and trans-but-2-enes presumably by an addition-elimination of HX with an intermediate (Ph,P),Pt(X)(CMe CHMe).353 The reactivity of the Pt"-acetylene complexes [L2Pt(R'CCR2)(Me)] -t (L = PhMe,P or Me,As) (compare ref.176) is reminiscent of that of a cyclopropenyl cation; thus reactions with alcohols give ring-opening products of type Pt+CR' :CR20Me (with loss of methane); hydride shifts (R' = H) give the carbene complex precursor MePt-C=CHR2 or cause methane elimination to give alkynyls P t 4 - R 2 ; and in methylene chloride a methyl shift gives ;t-C(R') C(Me)R2.354 Diphenylacetylene forms a deep-green 1 1 complex with anhydrous copper bis(hexafluoroacety1acetonate) ; complex formation is confirmed by proton n.m.r. shifts and several olefins have been shown to react similarly.355 Miscellaneous. Tetracyanoethylene (tcne) reacts with bis(phenylisonitri1e)-palladium to give (PhNC),Pd(tcne) in which PhNC is readily replaceable by phosphine ligands but tcne is not.Reaction of (PhNC),Rh(PPh,),+CI- with tcne gives neutral (PhNC),Rh(PPh,)(tcne)Cl ; thus co-ordination of the electron-withdrawing tcne makes four-co-ordinate Rh' a better electron-acceptor. In general co-ordination of tcne increases the CN stretching fre-quency of the isonitrile and also its lability.356 Dicyanoacetylene C4N2 gives the complex (Ph,P),Rh(CO)Cl(C,N,). The iridium analogue (Ph,P),Ir(CO)-(C4N2)C(CN) CHCN and (Ph,P),PdC4N2 are also formed. The CO stretching frequencies of iridium carbonyl complexes indicate that C4N2 is a poorer acceptor than tcne. 5 7 In tetraphenylbutatrienetetracarbonyliron Ph,C C C CPh,Fe(CO) iron is co-ordinated to the central bond the butatriene lying in the equatorial plane I I + + 3 5 0 3 5 1 3 5 2 3 5 3 3 5 4 3 5 s 3 5 6 3 5 7 D.Seyferth and D. L. White J . Organometallic Chem. 1971 32 317. ( a ) M. A. Bennett G. B. Robertson P. 0. Whimp and T. Yoshida J . Amer. Chem. Soc. 1971,93 3797; (b) G. B. Robertson and P. 0. Whimp J . Organometallic Chem., 1971 32 C69. B. E. Mann B. L. Shaw and N. I . Tucker J . Chem. Soc. ( A ) 1971 2667. P. B. Tripathy B. W. Renoe K. Adzamli and D. M. Roundhill J . Amer. Chem. Soc., 197 1,93,4406. M. H. Chisholm H. C. Clark and D. H. Hunter Chem. Comm. 1971 809. R. A. Zelonka and M. C. Baird J . Organometallic Chem. 1971 33 267. T. Boschi P. Uguagliati and B. Crociani J . Organometallic Chem. 1971 30 283. G. L. McClure and W.H. Baddley J . Organometallic Chem. 1971 27 155 Transition-metal Carbonyl Organometallic and Related Complexes 463 of a trigonal b i p ~ r a m i d . ~ ~ ~ (Ph,P),Ni catalyses the oligomerization of allene; (Ph,P),Ni(allene) can be isolated from the reaction mixture and mechanistic aspects of the reaction have been studied in the presence of other reactive mole-cules such as ethylene.359 In (Ph,P),Pt(allene) allene lies in the co-ordination plane of the metal and the carbon-carbon distances in the co-ordinated and unco-ordinated double bonds are 148 and 131 pm respectively.360 Three-carbon Ligands.-The structure of the cyclopropenyl complex (h3-C3Ph3)-Ni(hS-C,H,) has been described ; the nickel-3-ring carbon distances are shorter than those to the 5-ring carbon atoms (196 as against 210 pm) and the phenyl rings are twisted in a propeller configuration out of the C3 plane.361 The n.m.r.spectra of organometallic allyls have been reviewed.362 [(C6H6)-Mo(C,H,)Cl] and the toluene analogue may be prepared by oxidative addition of allyl chloride to the molybdenum bis(arene);363 these react further with allylMgBr to give (arene)molybdenumbis(allyl) and with TlBF followed by butadiene to give the [(arene)molybdenum(allyl)(butadiene)] + cations. These cations are attacked by nucleophiles Y- (e.g. H- from BH4- CN- or MeO-) to give the I-substituted n-ally1 complexes (arene)Mo(h3-C3H5)(h3-CH2CHCH.-CH2Y).364 The n.m.r. spectrum of (n-C,H,)Mo(CO),(n-allyl) has been compared with that of (h5-indenyl)Mo(CO),(n-allyl); large shifts in the allyl proton signals of the latter are attributed to ring currents in the indenyl benzenoid ring.365 The n-allyltetracarbonyls of manganese and rhenium are formed from the penta-carbonyl metal halides by reaction with allyltrimethyltin.Since (h1-C3H,)-Re(CO) does not give a n-ally1 complex under the conditions used it appears that replacement of CO by the allylic double-bond precedes or accompanies Me3SnBr elimination.366 Reaction of tetramethylalleneiron tetracarbonyl with acids (R = H) or acylating agents (R = MeCO or PhCO) gives the allyliron tricarbonyl cations [(h3-Me2CCR.CMe2)Fe(CO)J + ; these are deprotonated in warm acetone to 358 D. Bright and 0. S. Mills J . Chem. Sac. ( A ) 1971 1979. 3 5 9 R. J. de Pasquale J . Organometallic Chem.1971,32 381. 3 6 0 M. Kadonaga N. Yasuoka and N. Kasai Chem. Comm. 1971 1597. 3 6 1 R. M. Tuggle and D. L. Weaver Znorg. Chem. 1971 10 1504. 362 L. A. Fedorov Russ. Chem. Rev. 1970,39 655. 3 6 3 M. L. H. Green and W. E. Silverthorn Chem. Comm. 1971 557. 3 6 4 M. L. H. Green J. Knight L. C. Mitchard G. G. Roberts and W. E. Silverthorn, 365 J. W. Faller and A. Jakubowski J . Organometallic Chem. 1971 31 C75. 3 6 6 E. W. Abel and S. Moorhouse Angew. Chem. Internat. Edn. 1971 10 339. Chem. Comm. 1971 1619 464 P. S . Braterman give the diene complex [Me,C CRC(Me) CH,]Fe(CO) .367 Allene with Fe,(CO), gives (65) which is converted by heat into (66a) and thence to (66b); the structures are inferred by n.m.r. and that of (66b) has been confirmed crystallo-graphically.368 Reactions of isobullvalene and bullvalene with Fe,(CO) give, among other products (67) and (68) ; there is n.m.r.evidence for interchange of (68a) with (68b).369 Photochemical decarbonylation of (n-C,H,)Fe(CO),CH,-CMe,CH CH gives the straightforward product (n-C,H,)Fe(CO)~CH,CMe,. CH CH, but (n-C,H,)Fe(CO),CH,.CH,.CH2CH CH gives (n-C,H,)Fe(CO)-(n-C3H4Me) ; the latter reaction evidently involves P-hydrogen migrati~n.~” In a range of complexes of type [n-CH,C(Me)CH,],RuL, the asymmetry of the methylallyl groups is detectable by n.m.r. Temperature-variation and double-irradiation techniques demonstrate the occurrence of syn-anti interchange at high temperatures and also of a room-temperature left-right interchange that is explainable by an intramolecular The reaction mixtures in the cobalt-cyanide-catalysed hydrogenation of butadiene have been shown directly by n.m.r.to contain [(n-C,H,Me)Co(CN),]’ -at low cyanide cobalt ratios but both isomers of the a-but-2-enyl compound [MeCH CH.CH,.CO(CN),]~- for cyanide to cobalt ratios of 5 1 or more. This provides the expected kind of rationalization for the production of but-2-ene in the former case and but-1-ene in the latter although kinetic data suggest that the a-but-2-enyl compound is not in fact an intermediate.372 (Ph,P),Co(H)N, reacts with butadiene to give (h3-C3H4Me)(h4-C4H,)CoPPh, from which butadiene can be replaced by two molecules of C0.373 Addition of HCo(CO), to CH C(Me)-CH CH gives (h3-Me,CCH-CH,)Co(C0) whereas HIr(CO),-(PPh,) gives [h3-CH,C(Me)CHMe]Ir(CO)(PPh,) ; thus the more acidic 367 D.H. Gibson R. L. Vonnahme and J. E. McKiernan Chern. Comm. 1971 720. 3 6 8 S. Otsuka A. Nakamura and K. Tani J . Chem. Soc. ( A ) 1971 154. 369 ( a ) R. Aumann Angew. Chem. Internat. Edn. 1971 10 188; ( 6 ) R. Aumann ibid., p. 189. 3 7 0 M. L. H. Green and M. J. Smith J . Chem. SOC. ( A ) 1971,3220. 3 7 1 M. Cooke R. J. Goodfellow M. Green and G. Parker J . Chem. Snc. ( A ) 1971 16. 3 7 2 T. Funabiki and K. Tarama Chem. Comm. 1971 1177. 3 7 3 P. V. Rinze and H. Noth J . Organometallic Chem. 1971 30 115. Transition-metal Carbonyl Organometallic and Related Complexes 465 (cobalt-bonded) proton adds to the more basic double-bond (even though this gives the sterically more hindered product). 74 Allene reacts with bis(ethy1ene)-rhodium B-diketonates to give products (69); the crystal structure of (69b) has 0’ ‘ 0 I I (69) (a) R = Me (b) R = Ph been determined.Reaction of (cyclododecatriene)NiPCx,3 76a or of [ N ~ ( P C X ) ~ ] ~ N ~ ~ ~ ~ ’ with butadiene gives (70); there is disagreement about the existence of (h2-C4H6)2NiPCX as a precursor. Allylnickel hydride decomposes even at 135 K to give bis(allyl)nickel but phosphine adducts are stable to 245 K. I PCX, (70) Above 235 K the PF adduct isomerizes reversibly to (MeCHCH,)NiPF ; the deuteride transfers its label to C-1 or C-3 but not to C-2.377 [HNi(P(OEt),),]+ loses phosphite (this step is rate-determining) and then adds to butadiene to give [(n-C,H,Me)Ni(P(OEt),) ,] + (which in the presence of ethylene gives hexa- lP-dienes).Deuteriation studies of the analogous reaction with cyclo-pentadiene show addition of Ni-H to the diene to be cis.378 Reaction of allene with bis(cyc1o-octadiene)nickel followed by stabilization of the product with triphenylphosphine gives (7 l) characterized by n.m.r. and hydrogenolysis. Treatment of (71) with CS2 gives (72) by a reaction which formally at least is a 3 7 4 3 7 5 3 7 6 3 1 1 3 7 8 (71) (72) C. K. Brown W. Mowat G. Yagupsky and G. Wilkinson J . Chem. SOC. ( A ) 1971, 850. G . Pantini P. Racanelli A. Immirzi and L. Porri J . Organometallic Chem. 1971 33, C17. ( a ) P. W. Jolly I . Tkatchenko and G. Wilke Angew. Chem. Internat. Edn. 1971 10, 328 329; ( 6 ) J. M . Brown B. T. Golding and M. J. Smith Chem. Comm. 1971 1240.H. Bonnemann Angew. Chem. Internat. Edn. 1970,9 736. C. A. Tolman J . Amer. Chem. SOC. 1970,92,6777 6785 466 P. S . Braterman n-ally1 + a-ally1 conversion followed by ~oupling.~ 79 Norbornene adds to (n-2-methally1)nickel chloride dimer to give a mononuclear adduct. Acetate causes coupling to give (73a) by a cis-em-addition and the crystal structure of the palladium analogue (73b) has been rep~rted.~" Related compounds behave f 0' / \ (73) (a) M = Ni (b) M = Pd similarly,38 so that exo-co-ordination and exo-addition of nickel-group ally1 complexes to norbornene and norbornadiene appear to be general reactions. Addition of butadiene to (1-substituted-n-ally1)palladium halide dimers gives products [CH CHCHRCH2-h3-CHCHCH2PdX] ; thus the diene inserts between palladium and the more heavily substituted carbon.382 In such insertion reactions conversion of the parent n-ally1 into a a-ally1 complex cannot be rate-determining since butadiene causes rapid syn-anti interchange and the insertion products are not observed until after some time.383 The complex (ally1)-Pd(CNPh)Cl undergoes isonitrile insertion in the presence of triphenylphosphine to give [CH CHCH,C( NPh).Pd(PPh,)CI] .384 Bulky substituents at C-2 cause substituents at C-1 to prefer the anti-configuration contrary to what is found when c-1 is unsubstituted.In l-acetyl-2-methylallylpalladium chloride amines syn-anti interchange of the two protons at C-3 is much faster than interchange of syn-acetyl and anti-acetyl isomers which can however be demonstrated by saturation experiments.Careful analysis of the situation where the co-ordinated amine is optically active shows that inter-change both at C-1 and at C-3 takes place by the n-a-n mechanism.38s [CH, -CC1(CH,)2~h3-CMeCHCH,-PdCIl is an exception to the rule that syn-anti interchange is fastest at the less substituted of C-1 and C-3. This is no doubt because the free double-bond between C-1 and C-2 can displace C-6 C-7 and allow free rotation about the C-5-C-6 bond whereas when C-5 C-6 are dis-placed the conformation around the c-&C-7 bond remains anchored.386 3 7 9 S. Otsuka A. Nakamura S. Ueda and K. Tani Chem. Comm. 1971 863. 380 3 8 1 382 3 8 3 R. P. Hughes and J. Powell Chem. Comm. 1971 275. 3 8 4 T. Boschi and B. Crociani Znorg. Chim. Acta 1971 5 477.3 8 5 J. W. Faller M. E. Thomsen and M. J. Mattina J . Amer. Chem. Soc. 1971,93 2642. 3 8 6 D. J. S. Guthrie R. Spratt and S. M. Nelson Chem. Comm. 1971,935. M. C. Gallazi T. L. Hanlon G. Vitulli and L. Porri J. Organometallic Chem. 1971, 33 C45; M. Zocchi G . Tieghi and A. Albinati ibid. p. C47. R. P. Hughes and J. Powell J . Organometallic Chern. 1971 30 C45. D. Medema and R. van Helden Rec. Trav. chim. 1971 90 304 Transition-rnetal Carbonyl Organornetallic and Related Complexes 467 Monomeric adducts but no a-ally1 derivatives can be detected in bis-(n-allyl-palladium chloride) solutions to which donors have been added ;,'' this fact is of course mechanistically irrelevant. The 13C n.m.r. spectra of allylpalladium complexes show C-1 and C-3 to be intermediate between olefinic and a-co-ordinated CH, with C-2 in the olefinic (RCH :) region.Asymmetry is detectable in (n-C,H,)Pd(PPh,)CI ; one terminal carbon only shows coupling to phosphorus. This carbon which may be presumed to be trans to phosphorus is as expected the one at higher field (more olefini~).~'' The enthalpies of formation of crystalline and gaseous [(n-C,H,)PdCl] have been determined; a minimum value of 237 kJ mol- is estimated for the palladium-ally1 bond energy.389 Ally1 groups n-bonded to platinum change their mode of bonding more readily than those attached to palladium. Thus bis(n-ally1)platinum reacts with HCI to give [(allyl)PtC1] and with (acac)Tl to give [(allyl)Pt(acac)], in both of which ally1 is bridging. However [(allyl)PtC1] does react with donors to regenerate the n-ally1 system.Bis(n-2-methylally1)platinum gives both (cisoid and transoid) (n-2-methylallyl)platinum chloride dimers with HCI and with triphenylphosphine gives (Ph,P),Pt(o-CH2CMe CH,), Four-carbon Ligands.-Calculations on butadieneiron tricarbonyl show the charge distribution on the C ligand to correspond to a mixture of excited states ; as might be expected the n-electrons are more involved in metal-ligand bonding than are those of the o-frame~ork.~ 91 The basicities of p-butadienylaniline and its tricarbonyliron complex show that the tricarbonyliron dienyl grouping is electron-withdrawing with respect to hydrogen but less so than dienyl itself.392 The series Of compounds (h2-C,H6)Fe(CO)4 (h4-C4H6)Fe(CO) (h4-C4H6)-(h2-C&,)Fe(CO) and (h4-C4H6)2Fe(Co) have been prepared photochemically from butadiene and Fe(CO) ;393 the structure of the related bis(cycf0hexadiene)-iron monocarbonyl has been determined.94 (C4H6)2Fe(CO) may also be prepared by isopropyl Grignard qeduction of iron(II1) chloride in the presence of C4H6 and C0.395 In addition to the expected products photochemical reactions (74) (75) 387 L. A. Leites V. T. Aleksanyan S. S. Bukalov and A. Z . Rubezhov Chem. Comm., 3 8 8 B. E. Mann R. Pietropaolo and B. L. Shaw Chem. Comm. 1971 790. 3 8 9 S. J. Ashcroft and C. T. Mortimer J . Chem. SOC. ( A ) 1971 781. 3 9 0 B. E. Mann B. L. Shaw and G. Shaw J . Chem. SOC. (A) 1971; 3536. 3 9 1 P. G. Perkins I. C. Robertson and J. M. Scott Theor. Chim. Acta 1971,22,299. J92 J . M. Landesberg and L.Katz J . Organornetallic Chem. 1971 33 C15. 3 9 J ( a ) E. Koerner von Gustorf Z . Pfajfer and F.-W. Grevels Z . Naturforsch. 1971 26b, 66; (b) E. Koerner von Gustorf J. Buchkremer Z . Pfajfer and F.-W. Grevels Angew. Chem. Internat. Edn. 1971 10 260. 394 ( a ) C. Kruger and Y.-H. Tsay Angew. Chem. Internat. Edn. 1971 10 261; (b) C. Kruger and Y.-H. Tsay J . Organometallic Chem. 1971 33 59. 395 A. Carbonaro and A. Greco J . Organometallic Chem. 1970 25,477. 1971,265 468 P. S. Braterman of o-bromostyrene with Fe(CO)S give (74) and thence (75).396 Reaction of 1-bromo-2,3-dichlorocyclobutene with Fe2(CO) gives not the expected bromo-cyclobutadiene complex but the coupled product [(OC),Fe(h4-cyclo-C4H 311 2 a 3 Butadieneiron tricarbonyl undergoes photochemical substitution of CO with olefins but with Me0,C.C i CC0,Me the presumed analogous intermediate undergoes cycloaddition and isomerization to give dimethyl phthalate ; with cycloheptatriene the cycloaddition product (76) has been isolated.398 C7H8Fe(C0)3 undergoes 1,3-addition with tcne to give (77).399 2,3,4,5-Tetra-haptocycloheptatrienone is protonated by acids not at 0 but at C-7.400 The A ' Fe' (NC)2C\C(CN)2 0 exo-(tosylmethy1)cyclopentadiene derivative (78a) undergoes acid promoted ring expansion to (78b); but the endo-tosylmethyl isomer does not undergo this rea~tion.~" The interconversion of the 1,2,3,4-tetrahapto- and 5,6,7,8-tetrahapto-isomers of 1 -phenyl-2-tolyloctatetraene occurs directly as well as stepwise via CH2-0.S02.C,H,Me ,- -I+ ( 7 W (78b) the 3,4,5,6-tetr~hapto-isomer.~~~ The displacement of cyclo-octatetraene from its tricarbonylruthenium complex by phosphines proceeds by a mechanism403 C8H8Ru(C0)3 sk C8H8Ru(CO)3L Ru(C0)3L2 + CgH8 Cationic butadienepalladium chlorides are formed by chloride abstraction when 1-chloromethylallyl palladium chloride dimers are treated with strong acids; the cis-tetrahapto nature of the diene is confirmed by n.m.r.404 The 396 R.Victor R. Ben-Shoshan and S . Sarel Chem. Comm. 1971 1241. 3 9 7 H. A. Brune G. Horlbeck and U.-I. Zahorsky Z. Naturforsch. 1971 26b 222. 398 J. S. Ward and R. Pettit J. Amer. Chem. SOC. 1971 93 262. 399 J. Weaver and P. Woodward J. Chem. SOC. ( A ) 1971 3521. 400 A. Eisenstadt and S. Winstein Tetrahedron Letters 1971 613. 4 0 1 G.E. Herberich and H. Muller Chem. Ber. 1971 104 2781. 402 H. W. Whitlock jun. C. Reich and W. D. Woessner J. Amer. Chem. SOC. 1971 93, 2483. 403 F. Faraone F. Cusmano and R. Pietropaolo J. Organometallic Chem. 1971 26 147. 404 J . Lukas and P. A. Kramer J. Organometallic Chem. 1971 31 111 Transit ion-me tal Carbon y I 0 rganome tallic and Related Complexes 469 substituted cyclopentadienes C Me,Y give complexes C5 Me 5Y PdC12 with palladium(I1) chloride; the more bulky of Me and Y adopts the exo-position at the saturated carbon and it is suggested that the ligand is distorted towards a homocyclobutadiene ~tructure.~~’ Related platinum complexes may be prepared in acidic solution either from C5Me,Y or (for Y = H) from hexa-methyl Dewar-benzene ; the mechanism of this latter reaction is discussed.406 Pt(CO),Cl with diphenylacetylene in ether gives (in addition to C6Ph6 and tetracyclone) polymeric cyclo butadiene complexes [Ph4C,PtC12] ; these react reversibly with alkoxide to give the cycloallyls (79).,07 (79) Fivecarbon Ligands.-Reviews have appeared on metallocene homoannular electronic effects,408 and on the photochemistry of the m e t a l l o c e n e ~ .~ ~ ~ The compounds (C,H,),Ce and (indenyl),Ce have been prepared using NaC,H5 and NaC9H7 ; they are described as covalently bonded stable to dilute acid and to heat below 490K.410 (C5H5),UCl has been isolated from the reaction of UCl with C,H,T1.411 The fluorine of (C5H5)3UF acts as a donor to C,H,U and CSH5Y as shown by the composition of the products and the lower-ing of the uranium-fluorine stretching frequency.,’ The tris(cyc1opentadienides) of americium and curium show very small nephelauxetic effects and should be regarded as ionic.413 The compound (C,Me5),TiMe2 (from the dichloride and methyl-lithium) loses methane at 373 K in toluene; the product of composition (C5Me,),TiCH, is converted by hydrogen into (C,Me,),Ti.The latter is thought from magnetic and n.m.r. evidence to exist in solution as an equilibrium mixture of monomer and dimer ; it reacts with carbon monoxide to give (C,Me,),Ti(CO) with hydrogen reversibly to give a hydride and with nitrogen to give (C,Me,),-TiNNTi(C,Me,) .,14 Treatment of (n-C,H,),TiMe with hydrogen gives 4 0 5 4 0 6 4 0 7 4 0 8 4 0 9 4 1 0 4 1 1 4 1 2 413 4 1 4 P.V. Balakrishnan and P. M. Maitlis J . Chem. SOC. ( A ) 1971 1721. P. V. Balakrishnan and P. M. Maitlis J . Chem. SOC. ( A ) 1971 171 5. F. Canziani P. Chini A. Quarta and A. Di Martino J . Organometallic Chem. 1971, 26 285. D. W. Slocum and C. R. Ernst Organometallic Chem. Rev. 1970 A6 337. R. E. Bozak Adv. Photochem. 1971,8 227. 8. L. Kalsotra S. P. Anand R. K. Multani and B. D. Jain J . Organometallic Chem., 1971 28 87. P. Zanella S. Faleschini L. Doretti and G . Faraglia J . OrganometaNic Chem. 1971, 26 3 5 3 . B. Kanellakopulos E. Dornberger R. von Ammon and R. D. Fischer Angew. Chem. Internat. Edn. 1970 9 957. L. J. Nugent P. G. Laubereau G. K. Werner and K. L. Vander Sluis J. Organometallic Chem. 1971,27 365. J . E. Bercaw and H. H. Brinzinger J .Amer. Chem. SOC. 1971,93 2045 470 P. S. Braterman oligomeric [(C,H,),TiH], which in ether is converted into true titanocene, (n-C,H,),Ti. This material has an i.r. spectrum as expected for a metallocene; it is metastable with respect to pseudotitanocene dimer [CloH,TiHJ2 and reacts similarly to (C,Me,),Ti with CO H, and N2.415 The e.s.r. spectra of the titanium(II1) hydrides (n-C5H5),TiH2Na (n-C,H,),TiH,MgBr (?&H5)2-TiH2A1Cl, and (n-C5H,),TiH2A1H2 have been obtained both in solution and in glasses. It appears that the titanium is pseudo-tetrahedral with the odd electron in one orbital bisecting the HTiH angle and that contrary to previous claims, the aluminium chloride hydride complex is bridged syrnmetri~ally.~'~ Two time-averaging processes have been identified in (h5-C5H,),Ti(h'-C,H,) ring whizzing which is fast above 250 K and interchange of mono- and pentu-hupto-rings.The latter process which becomes fast between 250 K and 315 K has a low activation energy (67 kJ mol-') attributed to attack on the metal by the free n-electrons of the monohapto-ring. (C,H,),TiCl shows only one peak down to 175 K ;417 this is not totally surprising in view of the structure418 and bonding4I9 in (h5-C,H,),Zr(h'-C5H,). Zirconocene dichloride reacts with the bipyridyl dianion to give (C,H,),Zr(bipy) ; 'zirconocene' itself reacts with bipyridyl and benzene to give a product monomeric and undissociated in THF of stoi-cheiometry CloH loZr(bipy)(C6H,).420 Reduction of (n-C,H,)V(CO) to the dianion [(n-C,H,)V(C0,)l2- followed by acidification gives a material (C,H,),V,(CO) ; this is assigned the structure (80) from its low dipole moment and rich v(C0) i.r.Solid (n-C,H,)V(O,CCF,) is dimeric all trifluoroacetate groups being bridging. The vanadium-vanadium distance of 370 pm precludes direct bonding ; the low magnetic moment is due to s~perexchange.~~~ (n-C,H,),VCl reacts with 2,2'-dilithio-octafluorobiphenyl to give (8 1) ; and vanadocene (which has 4 1 5 4 1 6 4 1 7 4 1 8 4 1 9 4 2 0 4 2 1 4 2 2 R. H. Marvich and H. H. Brinzinger J . Amer. Chem. SOC. 1971 93 2046. J. G. Kenworthy J. Myatt and M. C. R. Symons J . Chem. SOC. ( A ) 1971 1020. J. L. Calderon F. A. Cotton and J. Takats J . Amer. Chem. SOC. 1971,93 3587. V. I. Kulishov E. M. Brainina N. G. Bokiy and Yu. T. Struchkov Chem.Comm., 1970,475. Ann. Reports ( A ) 1970 435. P. C. Wailes and H. Weigold J . Organometallic Chem. 1971,28,91. E. 0. Fischer and R. J. J. Schneider Chem. Ber. 1970 103 3684. G. M. Larin V. T. Kalinnikov G. G. Aleksandrov Yu. T. Struchkov A. A. Pasynskii, and N. E. Kolobova J . Organometallic Chem. 1971 27 53 Transit ion-me tal Carbon y 1 0 rganome tallic and Related Complexes 47 1 three unpaired spins) reacts with acetylenes to give n-complexes (h5-C5Hs)2-V(RCCR). The latter have only one unpaired spin and may be regarded formally as V" metallacyclopropenes. These facts confirm the view that the general inaccessibility of compounds (C5H5)2VR2 is due to steric rather than electronic factors. As might then be expected since Nb" is bulkier than VIV it more closely resembles Ti" in the range of its chemistry.Relatedly Ti"' Zr" and Nb"' all give bis-(n-cyclopentadieny1)-n-allyls but the V"' compound is a a - a l l ~ l . ~ ~ The compound (I~-C,H,)~N~H may be prepared from niobium(v) chloride C,H,Na and NaBH under 800atm hydrogen. This trihydride reacts with ligands L (e.g. PEt or C2H4) to give (n-C,H,),Nb(H)L and with dienes to give n-allyls. When heated to 355 K in benzene it loses hydrogen to give a pseudoniobocene, formulated from its n.m.r. spectrum as a bridged dimer [(n-C,H,)Nb(H)],-[C5H4I2 ; this catalyses H2-C6D6 exchange. (n-C5H5)2Nb(H)(C2H4) reacts further with ethylene to give (n-C,H,)2Nb(C2H,)(C2H4) ; this may be hydro-genolysed in the presence of excess ethylene with loss of ethane.424 Complexes (Ph,PC,H,)M(CO) (Ph3PC5H = Ph3P-h5-CSH,- ; M = Moor W) react with diazonium salts to give [Ph3PC5H,M(CO),.N2Ar] + with acidified CCl or CBr to give [Ph3PC5H4M(C0)2X]+ (X = C1 or Br) with one-electron oxidizing agents to give [Ph3PC5H4Mo(CO),]22+ and with a variety of diverse acceptors (SO2 ; halides of indium cadmium and mercury) to give M-bonded add~cts.,~' Reaction of [(n-CSH5)M(CO),]- (M = Mo or W) with diazoacetic ester gives (82); this may be methylated by methyl iodide at one nitrogen and + (n-C,H,)(OC),M,@ I c-c I I HO COOEt (82) protonated by acids at both.426 Substitution of CO by phosphines in (n-C,H,)-Mo(CO),Cl or in the tetrahydroindenyl analogue (hS-C,H1 1)Mo(CO)2Cl, proceeds by an SN1 pathway; however the reaction of the indenyl complex is faster and has an SN2 component427 [possibly owing to indenyl acting as h3-( 1,3-o-pheny1ene)allyl in an associated intermediate].The limiting low-temperature n.m.r. spectra of species (~c-C,H,)MO(CO)~(L)R are known to show separate signals for cis- and trans-isomers ; for (~-C,H,)MO(CO)(PM~P~~)~C~ the coales-cence temperature is 211 K [150 K lower than for species (~-C,H,)MO(CO)~-(L)Cl] and that of (n-C5H5)Mo(CO)(PMe2Ph),C1 is yet lower; this is probably a steric effect and is consistent with interconversion uia a state of effective 3 3 1 4 2 3 H. J. de Liefde Meijer and F. Jellinek Znorg. Chim. Acra 1970,4 651. 424 F. N. Tebbe and G. W. Parshall J . Amer. Chem. SOC. 1971,93 3793. 4 2 5 D. Cashman and F. J. Lalor J. Organometallic Chem. 1971 32 351. 4 2 6 M.L. H. Green and J. R. Sanders J. Chem. SOC. ( A ) 1971 1947. 4 2 7 C. White and R. J. Mawby J . Chem. SOC. ( A ) 1971,940 472 P. S. Bratermun co-ordination geometry [compare (83)].428 The cis-isomer of (n-indeny1)-Mo(CO),(PMe,Ph)I (84) is chiral as is the possible transition state (83) but the possible transition state (85) is achiral as is the trans-isomer (86). Racemization of (84) oia (85) can thus proceed without conversion into (86) (i.e. without cis-trans isomerization) but isomerization must accompany racemization via (83). oc\ I oc I / L oc/ oc' ' L oc R/Mo\ co /Mo-R OC I / R Mo R \ I Mo-L (84) (85) (86) 0 (83) In fact racemization without isomerization can be detected (by the averaging of indenyl H-1 and H-3 with concomitant averaging of ligand diastereotopic methyls); isomerization also occurs but more slowly.429 The n.m.r.spectra of (C,H,),Mo(NO)I and (C,H,),Mo(NO)Me show no broadening of the singlet ring-proton signal down to 150 K. Treatment of (n-C,H,),MoI with C5HST1 gives (h5-C5H5)2(h'-C5H,)2M~ in which the h' rings are fluxional at 300 K.430 Reaction of [(n-C H ,)Mo(NO)I ,] with (n-C H ,)Mo(NO) (CO) gives [(n-C,H,)Mo(NO)I] ; the reaction is reversed by I,. It is suggested that the bis(di-iodide) contains both bridging and non-bridging iodine but no metal-metal bond whereas the bis(iodide) contains both iodine and nitrosyl bridges and is metal-metal bonded. The bis(di-iodide) reacts with iodide to give [(n-C,H5)-Mo(NO)I,] - with thiolate anions to give [(n-C,H,)Mo(NO)(SR),], and with ligands (phosphines arsines isonitriles) to give (n-C,H,)Mo(NO)I,L ; these last are ionized in good donor solvents (e.g.acetone or DMS0).431 [(n-c5H5)2-Mo(PPh,)Br] + PF6- reacts with sodium borohydride which replaces Br by H.432 Such olefins as maleic ester insert into one metal-hydrogen bond of tungstenocene dihydride ; the product ( x - C ~ H ~ ) ~ W(H)(R) then reversibly loses HR to give tungstenocene which reacts further with benzene to give (n-CgH5)2-W(H)Ph and with maleic ester to give a n-(or metallacyclopropane) complex. Treatment of tungstenocene dihydride with butyl-lithium gives what is thought to be [(n-C,H,),WH]-; this species reacts with acetyl chloride to give (n-C,H,),W(H)COMe and with benzophenone to give (n-CSH,)W(H)-C6H4-COPh.43 Reaction of [(n-C5H,)W(C0)3]2Hg with aluminium metal in THF gives [(n-CSH5)W(CO)3]3A1(THF)3 which shows very low wavenumber ( - 1600 4 2 8 4 2 9 4 3 0 4 3 1 4 3 2 4 3 3 G.Wright and R. J. Mawby J. Organometallic Chem. 1971 29 C29. J. W. Faller A. S. Anderson and A. Jakubowski J . Organometallic Chem. 1971 27, c 4 7 . J. L. Calderon and F. A. Cotton J . Organometallic Chem. 1971,30 377. T. A. James and J. A. McCleverty J . Chem. SOC. (A) 1971 1068 1596. R. H. Crabtree A. R. Dias M. L. H. Green and P. J. Knowles J . Chem. SOC. ( A ) , 1971 1350. B. R. Francis M. L. H. Green and G. G. Roberts Chem. Comm. 1971,1290 Transition-metal Carbonyl Organometallic and Related Complexes 473 cm-') v(C0) bands in solution as well as normal bands; the crystal structure shows A13+ co-ordinated by three THF and three carbonyl oxygen^.^^^ How-ever species (n-CSH,)W(CO),A1R2 appear from solution i.r.to exist in both 0- and W-bonded forms.435 The n.m.r. spectrum of (n-C,H,)Mn(CO) in a nematic solvent has been meas-ured and both direct and indirect coupling constants have been determined.436 The n.q.r. spectra of a range of substituted n-cyclopentadienylmanganese tri-carbonyl compounds have been obtained and correlated both with ring proton n.m.r. and with U.V. shifts ; n-conjugating substituents (e.g. -C02H but par-ticularly -COR) lower the resonance frequency as expected.43 Reaction of tropone with Mn,(CO), gives the pentadienyl complex (87); the terminal CH2 0 \I ,c x- HC - CH / CH2 Mn (87) v group is twisted 48" out of the plane of the C ligand.438 Photolysis of (n-C,H,)-Re(C0)3 gives [(n-C,H,)Re(CO)2]2[CO] in which the rhenium-rhenium bond length is 296pm and the ReCRe angle at the solitary bridging carbonyl is The high-energy photoelectron spectra of ferrocene biferrocene ferroceneFe"' picrate ferroceneFe"' fluoroborate biferroceneFe"Fe"' picrate and biferro-ceneFe"'Fe"' fluoroborate have been obtained ; the valence electron region of biferrocenyl is little different from that of ferrocene (the same is true of the U.V.spectrum) showing that the interaction between the two ferrocenyl groups is small. As might then be expected the charge in the Fe"Fe"' species is localized, so that separate signals are given by the oxidized and unoxidized ferrocenyl moieties.440 At 4.2 K the 22 700 cm-' band of ferrocene is seen to have two distinct electronic components ; the corresponding bands of ruthenocene and (n-C5H5)2C~+ are similar.The low-energy (16 200 cm-') band of the ferrocene-Fe"' cation is from the effects of temperature and substituents a ligand-to-metal charge-transfer band assigned as 2E2 + 2E l u with a vibrational structure due to a doubled progression attributed to splitting of the excited state.44' The appreciable orbital contribution to the magnetic moment of [(n-C,H,),Fe] -t 4 3 4 R. B. Petersen J. J . Stezowski Che'ng Wan J . M. Burlitch and R. E. Hughes J . 4 3 5 R. R. Schreike and J. D. Smith J . Organometallic Chem. 1971 31 C46. 4 3 6 G. L. Khetrapal A. C. Kunwar and C. R. Kanekar Chem. Phys. Letters 1971,9,437. 4 3 7 T. B.Brill and G. G. Long Inorg. Chem. 1971 10 74. 4 3 8 M . J. Barrow 0. S. Mills F. Haque and P. L. Pauson Chem. Comm. 1971 1239. 4 3 9 A. S. Foust J. K. Hoyano and W. A. G. Graham J . Organometallic Chem. 1971,32, C65. 440 D. 0. Cowan J. Park M. Barber and P. Swift Chem. Comm. 1971 1444. 4 4 1 Y. S. Sohn D. N. Hendrickson and H. B. Gray J . Amer. Chem. Soc. 1971,93 3603. 920 4 3 9 Amer. Chem. Soc. 1971 93 3532 474 P. S. Braterman confirms the assignment of a split 2E,(a1g2 eg3) ground state but the failure of the moment to vary with temperature could be due either to a temperature-dependent splitting or to population of the ulg1eg4 state.442 For the biferrocene Fe"Fe"' cation magnetic and e.s.r. studies over a wide temperature range show that the latter state is not thermally acce~sible.~~' However this area is fraught with daculties and a 77 K spectrum claimed444 for ferroceneFe"' is demon-strably due to an Deuterium labelling studies show that in ferrocenylamine the shielding effect on proton n.m.r.signals of the electron-donating substituent is felt mainly at the 3- and 4-positions of the ring.446 The low-wavenumber (< 300 cm- ') i.r. and Raman spectra of the bis-(nindenyl) complexes of iron and ruthenium show a lowering of the symmetric metal-ring stretching frequency relative to the metallo-cenes ; the effect is electronic [since bis(tetrahydr0-71-indeny1)ruthenium shows a frequency greater than that of ruthenocene] and is attributed to the electron-withdrawing effect of the uncomplexed aromatic ring.447 Ferrocene ruthenocene, and osmocene all show reversible one-electron oxidation at a dropping mercury electrode ; the ease of oxidation increases down the Periodic Table and substituent effects appear to be inductive rather than r n e ~ o m e r i c .~ ~ ~ Ferrocene undergoes photochemical oxidation to ferroceneFe"' in CHCl or CCl, but only if irradiated in the charge- transfer-to-solven t region.44 [(n-CSH5)2Fe2(C0)4]" may be oxidized or reduced polarographically over the range n = + 2 to - 1 without decomposition; [(7t-C5H5)FeSI4" similarly spans the range from + 3 to - l.450 Oxidation of (Z-C,HJ~F~~(CO)~ at carbon or platinum electrodes in donor solvents or in the presence of ligands gives a general route to species [(n-C,H,)Fe(CO),L] + and (.n-CSH,)Fe(CO),X.45 ' The cation [x-C5HsFe(C0)l2[SMe],+ is cisoid with an iron-iron distance of 292 pm and bridging FeSFe angles of 82" ; this is consistent with an iron-iron bond order of less than (n-C5H5)2Fe2(C0)4 is a proton acceptor in anhydrous HCI, giving a centrosymmetric species { [(x-C,H,)Fe(CO),],H} + ; (IT-C,H,)F~(CO),C~ also acts as a base reacting with BCl to give ([(x-C,H,)Fe(CO),],Cl) +BC14-.453 The shift reagent Eu(fod) (fod = C,F,.COCH,COEt) detects a rather different kind of basic behaviour; (TC-C,H,),F~~(CO) shows a shift attributed to co-ordination of bridging CO whereas the methyl derivative (n-C,H,)Fe(CO),Me, and the corresponding bromide iodide and thiocyanate do not.The fluoride, 4 4 2 D. N. Hendrickson Y. S. Sohn and H. B. Gray Inorg. Chem. 1971 10 1559. 443 D.0. Cowan G. A. Candela and F. Kaufman J. Amer. Chem. SOC. 1971,93 3889. 444 A. Horsfield and A. Wassermann J. Chem. SOC. ( A ) 1970 3202. 445 R. Prins and A. G. T. G. Kortbeek J. Organometallic Chem. 1971 33 C33. 446 D . W. Slocum P. S. Shenkin T. R. Engelmann and C. R. Ernst Tetrahedron Letters, 1971,4429. 4 4 7 E. Samuel and M. Bigorgne J. Organometallic Chem. 1971 30 235. 448 S. P. Gubin S. A. Smirnova L. I. Denisovich and A. A. Lubovich J. Organometallic Chem. 1971,30,243. 449 0. Traverso and F. Scandola Inorg. Chim. Acta 1970 4 493. 4 5 0 J. A. Ferguson and T. J. Meyer Chem. Comm. 1971 623. 4 5 1 J. A. Ferguson and T. J. Meyer Inorg. Chem. 1971 10 1025. 4 5 2 N. G. Connelly and L. F. Dahl J. Amer. Chem. Soc. 1970 92 7472. 4 5 3 D. A. Symon and T.C. Waddington J. Chem. SOC. ( A ) 1971 953 Transition-metal Carbonyl Organometallic and Related Complexes 475 chloride azide and cyanide do show shifts and in the case of the cyanide v(CN) is increased as expected if cyanide donates through nitrogen to a ‘hard’ acid. Thus the shift reagent is detecting ‘hard’ base character ; this is also shown by the non-bridging but low-frequency carbonyls of (Ph,P),(phenanthr~line)Mo(CO)~, and by (presumably) the metal lone pair of (n-C5H5),WH2 . 1 7 (~-C,H,)RU(CO)~CI reacts with NaBPh to give (n-C,H,)Ru(CO),Ph ; (n-C5H,)Ru(PPh,),C1 reacts to give (n-C,H,)RuPhBPh, in which one phenyf ring is both n-bonded to Ru and o-bonded to B.,’, Heating (n-C,H,)Co(CO)I in hydrocarbons yields polymeric [(n-C,H,)-CoI,] ; this reacts with donors to give products (n-C,H,)CoLI, and with polar solvents to give [(n-C,H,),Co]+ .,” Photo-a-pyrone (88) reacts photochemically (88) with (~-C,H,)CO(CO)~ to give the cyclobutadiene complex (n-C,H,)Co(n-C4H4).This reacts further with excess starting material on continued irradiation to give (89) in which [(n-C,H,)Co] has inserted into the four-membered ring. At 41 5 K (60 MHz dichlorobenzene) the two cyclopentadienyl rings (i.e. presumably (89) the two cobalt atoms) interchange bonding situations but H and H remain d i s t i n ~ t . ~ ~ n-Cyclo-octenylcobalt cyclo-octadiene gives on heating in the presence of excess cod [x-cyclo( 1,2-trimethylene)-pentadienyl]cobalt(cod) ,457 and it reacts with cycloheptatriene to give the n-cycloheptadienyl complex (C,H,)Co(cod) from which cod is replaceable by CO or other ligands ; the low-temperature n.m.r.spectrum (below 250 K) shows non-equivalence among vinylic and methylenic protons indicating a static structure (90).“’* 4 5 4 R. J. Haines and A. L. du Preez J . Amer. Chem. SOC. 1971 93 2820. 4 5 5 D. M. Roe and P. M. Maitlis J . Chem. SOC. (A) 1971 3173. 4 5 6 M. Rosenblum W. P. Giering B. North and D. Wells J. Organometallic Chem., 4 5 7 H. Lehmkuhl W. Leuchte and E. Janssen J . Organometallic Chem. 1971 30 407. 4 5 8 S. Otsuka and T. Taketomi J. Chem. SOC. (A) 1971 579 583. 1971 28 C17 476 P. S. Braterman Cobaltocene reacts with the radical -CMe,CN to give (91 ; R = CMe,CN); thus cobaltocene traps Reaction with methyl chloroacetate gives cobaltocinium chloride and (91 ; R = CH,C0,Me),460 but methyl- and phenyl-boron dibromide give products (92) containing the hitherto unknown borinate (91) heterocycles as IigandE; these are Co" electron oxidation.461 The reaction of (n-CS H ~ ) C O (92) species and undergo reversible one-cobaltocene with phosphites gives a range of products principally (n-C,H,)Co[P(OR),] .462 The polarographic reduction of cobaltocinium to cobaltocene is reversible but the further reduction to the cyclopentadiene complex (h5-C,H,)Co(h4-C,H6) is irreversible.Similarly, nickelocene may be reversibly oxidized to (n-C,H,),Ni2 + and irreversibly reduced to the ally1 (h5-C H ,)Ni(h3-C5 H ,).46 (n-C5H,)Rh(PPh3)C2H4 has been obtained by the reaction of NaC,H with (acac)Rh(PPh3)C2H4 and (n-C,H,)Rh(PPh,)(C,F,) by the zinc debromination of (n-C5H ,)Rh(PPh3) (CF2CF2Br)Br.464 [( n-C,H ,)Ir(CO)PPh ,] - [from C,H ,Na and (Ph,P),Ir(CO)Cl] is a relatively strong base being protonated by acids, methylated by MeI and attached as a ligand to ZnBr, HgCl, and TlCl .465 The Raman spectrum of (C,H,)PtMe is consistent with a n-bonded cyclo-pentadienyl ring ;466 for the solid this has been confirmed ~rystallographically.~~~ Complexes of type (n-C,H,)M(L)X (M = Pd or Pt) react with excess L to give [(n-C,H,)ML,] 'X- or L,M(o-C,H,)X depending on the solvent and the nature of L.468 Reaction of C,H,Na with PtCl gives (93).469 The species C,Cl,HgCl and (C,Cl,),Hg are a-bonded and (on the n.q.r.time-scale) n o n - f l u ~ i o n a l . ~ ~ ~ (93) 4 5 9 G. E. Herberich and J. Schwarzer Angew.Chem. Internat. Edn. 1969 9 897. 460 G. E. Herberich and G. Greiss J . Organometallic Chem. 1971 27 113. 461 G. E. Herberich G . Greiss H. F. Heil and J. Muller Chem. Comm. 1971 1328. 462 V. Handler J. Muller and H. Werner Helv. Chim. Acta 1971 54 1. 463 S. P. Gubin S. A. Smirnova and L. I. Denisovich J. Organometallic Chem. 1971 30, 464 A. J. Oliver and W. A. G . Graham Inorg. Chem. 1971,10 1165. 4 6 5 A. J. Oliver and W. A. G. Graham Inorg. Chem. 1970,9,2653. 4 6 6 J. R. Hall and B. E. Smith Austral. J . Chem. 1971 24 911. 4 6 7 G. W. Adamson J. C. J. Bart and J. J. Daly J . Chem. SOC. ( A ) 1971,2616. 468 R. J. Cross and R. Wardle J . Chem. SOC. ( A ) 1971 2000. 4 6 9 K. K. Cheung R. J. Cross K. P. Forrest R. Wardle and M. Mercer Chem. Comm., 4 7 0 G.Wulfsberz and R. West J . Amer. Chem. SOC. 1971 93 4085. 257. 1971 875 Transition-metal Carbonyl Organometallic and Related Complexes 477 Ligands with Six or More Carbon Atoms.-The vibrational spectra of a large number of bis-benzene-metal complexes have been analysed in some detail; the marked shift in the free ligand A, mode [from 673 cm- in benzene to 794 cm-in bis(benzene)chromium] is due merely to kinematic effects. (C6H&Cr and (C,D&Cr were studied in some detail placing the six-fold symmetry of co-ordinated benzene beyond doubt.,, The crystal structure of U(AlCl,) ,C6H shows uranium n-bonded symmetri-cally to benzene and sharing two chloride bridges with each AlCl, Splitting of the v(C0) E band in C,H5XCr(C0) (X = F Me or OMe) is plainly observable in cyclohexane solution.473 The changes in 13C chemical shifts of arene- and cycloheptatriene-chromium tricarbonyl complexes give a measure of the change in mobile bond order that agrees well with that implied by the known changes in bond lengths.,, Bis(benzene)molybdenum reacts with a range of phosphines and phosphites to give complexes (C6H6)MoL3 ; for L = PMePh or PMe,Ph these are readily protonated to give cations in which the hydride chemical shift is unusually low (1&122) and there is apparent three-fold sym-metry on the n.m.r.time-scale even at 177 K475 (compare ref. 428). Ions of type [(arene),FeI2+ (from such arenes as mesitylene and hexamethyl-benzene with FeCl and AlCl,) undergo exo-addition with lithium alkyl~.,~, Arene complexes [(z-C5Me,)M(arene)12+ (M = Rh or Ir) may be prepared under relatively mild conditions from (n-C5Me5)M(OCOCF,),H20 arene and tri-fluoroacetic acid; the function of the acid is presumably to act as a trifluoro-acetate acceptor and the procedure may offer general advantages over the con-ventional use of metal halides with aluminium trichloride as the Lewis With (cod),Ni hexafluorobut-2-yne gives [C,(CF,),]Ni(cod) ; the diene is readily replaced by phosphine ligands to give products [C,(CF,),]NiL,.In these all fluorines are equivalent and equally coupled down to 185 K and there is no detectable v(C=C) i.r. band.478 The crystal structure of [C,Me,],Ru shows one ligand to be hem- and the other tetra-hapto to the metal.,,’ Tropone in (tropone)Cr(CO) is hexahapto with the CO group absorbing in the ketonic region and displaced exo from the plane of the co-ordinated carbons.480 Cyclo-heptatrienylacylmanganese pentacarbonyl C H,COMn(CO), is decarbonylated photochemically to give (h’-C,H,)Mn(CO) ; this is fluxional but averaging is 4 7 1 (a) S.J. Cyvin B. N. Cyvin J. Brunvoll and L. Schafer Acta Chem. Scand. 1970 9, 3420; ( 6 ) L. Schafer J. F. Southern and S. J. Cyvin Spectrochim. Acta 1971 27A, 1083; ( c ) J. Brunvoll S. J. Cyvin and L. Schafer J. Organometallic Chem. 1971 27, 69 107; (4 S. J. Cyvin J. Brunvoll and L. Schafer J. Chem. Phys. 1971,54 1517. 4 7 2 M. Cesari U. Pedrotti A. Zazzetta G. Lugli and W. Marconi Inorg. Chim. Acta, 1971 5 439. 4 7 3 G. Davidson and E. M. Riley Spectrochim. Acta 1971 27A 1649. 4 7 4 B. E. Mann Chem.Comm. 1971 976. 4 7 5 M. L. H. Green L. C. Mitchard and W. E. Silverthorn J. Chem. SOC. ( A ) 1971, 4 7 6 J. F. Helling and D. M. Braitsch J. Amer. Chem. SOC. 1970 92 7207 7209. 4 7 7 C. White and P. M. Maitlis J. Chem. SOC. ( A ) 1971 3322. 4 7 8 J. Browning C. S. Cundy M. Green and F. G. A. Stone J. Chem. SOC. ( A ) 1971,448. 4 7 9 G. Huttner S. Lange and E. 0. Fischer Angew. Chem. Internat. Edn. 1971 10 556. 480 M. J. Barrow and 0. S. Mills Chem. Comm. 1971 119. 2929 478 P. S. Braterman slower than in [C7H7Fe(C0),]+ and there is evidence for a ring current in the complexed ring.,' Reaction of TiCl in ether with Pr'MgX and cycloheptatriene gives (h7-C,H7)Ti(h5-C7H9).482 With CeC1,2 - cycloheptatriene gives (c7H7)2-CeCI, in which i.r. evidence indicates ligand n-bonding;483 by contrast the tetrachlorides of titanium zirconium and hafnium give with cyclo-octatetraene (C,H8) the products (h'-C8H7)2MC12.484 The cyclononatrienyl anion reacts with lanthanide cations to give unexpectedly complexes of h8-C8H82-.485 The crystal structure of the substituted cyclo-octa tetraene complex ( h8- 1,3,5,7-Me4C8H,) u reveals the presence of two conformers one approximately staggered and the other close to Strong acid (FS0,H-SO,F,, 150 K) converts (h4-C,H,)Fe(CO) into [(h5-C8H9)Fe(CO),]+ ; at 215 K this isomerizes by what is for the free ligand a Woodward-Hoffmann-allowed process, to (94).487 Reaction of C8H8 with PhCCo,(CO) gives (17).76y488 The low- cl I Fe( CO), (94) temperature n.m.r.spectrum collapses between 250 and 290 K ; the relative rates of peak coalescence imply (on a first-order analysis) a 1,Zshift mechanism.488 3 Main Group Ligands Hydride Complexes.-The general relationship found for main group metals between v(M -D) and the deuterium quadrupole coupling constant holds also for (n-C,H,),MD (M = Mo or W).489 Borohydride reduction of phosphine complexes L,MoCl in the presence of excess L gives species L,MoH4 ; these are diamagnetic and all hydrides are magnetically equivalent equally coupled to phosphorus at ca.7 = 12 (compare ref. 475).490 Isoelectronic with these, and similarly prepared are species FeH,L The complex H,Fe(PMe,) is the cis-isomer with the two kinds of hydrogen magnetically distinct at least up to 300 K ; the related species HCo(PMe,) does however show averaging of 4 8 1 4 8 2 H.0. van Oven and H. J. de Liefde Meijer J . Organometallic Chem. 1971,31 71. 4 8 3 B. L. Kalsotra R. K. Multani and B. D. Jain J . Organomerallic Chem. 1971 31 67. 4 8 4 K. M. Sharma S. K. Anand R. K. Multani and B. D. Jain J . Organometallic Chem., 4 8 5 F. Mares K. 0. Hodgson and A. Streitweiser jun. J . Organometallic Chem. 1971, 486 K. 0. Hodgson D. Dempf and K. N. Raymond Chem. Comm. 1971 1592. 4 8 7 4 8 8 B. H. Robinson and J. Spencer J. Organometallic Chem. 1971 33 97. 4 8 9 I. Y. Wei and B. M. Fung J . Chem. Phys. 1971 55 1486. 490 F. Pennella Chem. Comm. 1971 158. 4 9 1 T. H. Whitesides and R. A. Budnik Chem. Cornm. 1971 1514. 1970 25 447. 28 C24. M. Brookhart and E. R. David J . Amer. Chem. SOC. 1970 92 7622. M.Aresta P. Giannocaro M. Rossi and A. Sacco Inorg. Chim. Acta 1971 5 115 Transition-metal Carbonyl Organometallic and Related Complexes 479 positions. The metal-hydrogen frequencies are low compared to the PF, analogues and there is no acidic character.492 The species [HRu(PF,),]-, [HOs(PF,),]- HM(PF,) (M = Co Rh or Ir) are fluxional at room temperature. The low-temperature n.m.r. spectra are complex with axial phosphorus-hydrogen coupling large. The activation free energy for averaging is 25 kJ mol- ’ for the cobalt compound and around 35 kJ mol- for the second- and third-row Averaging also occurs in the n.m.r. spectrum of HCo[P(OEt),Ph],, the crystal structure of which shows strong distortion towards a tetrahedral arrangement of the phosphorus ligand~.,~ Cobalt@) cobaloximes and cobala-mines are protonated at the metal in aqueous acid solution.495 The rate of reaction of [Co(CN),HI3 - with mercury(u) halides (to give [Co(CN),HgXI3 - and { [CO(CN),],H~)~-) is determined by the deprotonation of the cobalt hydride to [ C O ( C N ) ] ~ - .~ ~ ~ Hydrogen reacts with [Co(bipy),]+ in the presence of phos-phines to give species [Co(bipy)L,H,] + ; these reduce dienes to give monoenes, together with species [Co(bipy)L(diene)] + ; all these reactions are reversible.497 Phosphine ligands of type Bu‘,RP react with rhodium(II1) and iridium(II1) chlorides in alcoholic solution to give species ML,Cl,H ; the crystal structure of the rhodium derivative shows a square pyramid with hydrogen at the apex and the other ligands in a plane in the trans-configuration.The hydrogens are excep-tionally strongly shielded (z = 41 for Rh 60 for Ir).498 Hydrogen reacts with the chloride-bridged species [(n-C5Me,)RhCl,] to replace one bridging chlorine ; the resultant [(n-C5Me,),RhCI],[C1] [HI reacts with conjugated dienes to give (n-C5Me5)Rh(Cl)(h3-allyl) together with the original Species trarzs-(Cx,P),NiHCl and trans-(Pr’,P),NiHCl may be prepared by borohydride attack on the dichloride; chloride exchanges with Br- SCN- or CN-. Their stability compared to the Pr”,P analogues is attributed to steric factor^.^" Cationic hydrides of palladium [(dppe),PdLH]+ result from the reaction of dppe with L,PdHCl (L = e.g. PCX,).’~~ The cationic platinum hydride [trans-(Ph,MeP),PtH(acetone)] + is formed when AgPF in acetone reacts with the neutral hydride bromide.The ease with which this undergoes insertion of ethylene or propylene strongly suggests that formation of four-co-ordinate species [L,Pt(H)(alkene)] + rather than of five-co-ordinate species is rate-limiting in such insertions at Pt.,02 The reputed503 species ‘(Ph,P),PtH,Cl,’ 4 y 2 4 9 3 P. Meakin J. P. Jesson F. N. Tebbe and E. L. Muetterties J. Amer. Chem. SOC. 1971, 494 D. D. Titus A. A. Orio R. E. Marsh and H. B. Gray Chem. Comm. 1971 322. 4 9 5 496 H. S. Lim and F. C. Anson Inorg. Chem. 1971 10 103. 49’ G. Mestroni A. Camus and C. Cocevar J. OrganometaNic Chem. 1971 29 C17. 4 y 8 ( a ) C. Masters B. L. Shaw and R. E. Stainbank Chem. Cornm. 1971 209; ( b ) C. Masters W. S. McDonald G. Raper and B. L. Shaw ihid.1971 210. 4 9 9 C. White D. S. Gill J. W. Kang H. B. Lee and P. M. Maitlis Chem. Comm. 1971, 734. M. L. H. Green T. Saito and P. J. Tanfield J . Chem. SOC. ( A ) 1971 152. M. L. H. Green and H. Munakata Chem. Comm. 1971 549. H. C. Clark and H. Kurosawa Chem. Comm. 1971 957. F. Cariati R. Ugo and F. Bonati Inorg. Chem. 1966 5 1128. H.-F. Klein Angew. Chem. Internat. Edn. 1970 9 904. 93 1797. G. N. Schrauzer and R. J. Holland J. Amer. Chem. SOC. 1971,93,4060. 5 0 1 5 0 480 P. S . Braterman is in fact a form of (Ph3P)2PtHC1.504 The species H&U6(PPh3)6 {from [(MeO),BH] - reduction of the tetrameric chloride) is approximately octa-hedral with the phosphines terminal and the hydrogens presumably bridging the edges of two opposite faces since these edges appear lengthened.," Group 111.-(See also Chapter 13.) Metal-boron compounds have been re-viewed.'06 In (OC),Cr(B,N,Et,) the ring is puckered with the metal-boron greater than the metal-nitrogen distance ; this could however be due merely to the different radii of B and N.,07 (Ph,P)2NiC2H reacts with diphenylboron bromide in ether to give among other interesting products polymeric solvated (Ph3P),Ni.BPh2 in which boron may be bridging."* Complexes (R,P),PtB,H,, from (R,P),PtCl and (B3H8)- have been shown by high-energy photoelectron spectroscopy to be Pt" compounds; the boron ligand is formulated as [H2B(H)BH(H)BH,I2- an analogue of n - a l l ~ l .~ ' ~ Species R',AI.Mo(n-C,H,)-(CO),L [from reaction of R',Al or R',AlH with (n-CSH5)Mo(C0),LH ; compare ref.4351 are cleaved quantitatively by alcohols R20H which give R',A10R2 and regenerate the molybdenum hydride; thus the AI-Mo bond is solvolysed in preference to those between aluminium and carbon. lo Compounds InXM [X = halogen M = (n-C5H5)Mo(CO), (n-C,H,)-W(CO), or (n-C,H,)Fe(CO),] are accessible either by InX insertion into the metal-metal bond or by displacement of mercury from the compounds HgM2.," In[Mn(CO),] and XIn[Mn(CO),] both ionize in acetonitrile to give the species {In[Mn(CO),],} +. l 2 The ions {In[Co(CO),],} - and {Tl[Co(CO),],} -appear tetrahedral on i.r. evidence ;' ' B~,I~[CO(CO),]~ - shows highly distorted -Co(CO) groups with considerable deviations from linearity in the 0-C-Co groupings. l4 Group 1V.-The chemistry of transition-metal Group IV derivatives has been reviewed.,15 Mossbauer studies on a range of compounds such as Mn(CO),-SnCI, [(n-C,H,)Fe(CO),],SnCl, (n-C,H,)Fe(CO)(L)SnR show the tin to be Sn'" the tin-metal bond being highly covalent.The variations in isomer shift at iron and at tin when CO is replaced by a less electron-accepting ligand show the expected decrease in s-electron density at iron but an increase at tin; this shows that changes in tin-iron o-bonding outweigh any variations in n-bond-5 0 4 J. T. Dumler and D. M. Roundhill J. Organometallic Chem. 1971 30 C35. S. A. Bezman M. R. Churchill J. A. Osborn and J. Wormald J. Amer. Chem. SOC., 1971,93,2063. 5 0 6 G. Schmid Angew. Chem. Internat. Edn. 1970 9 819. 5 0 7 G. Huttner and B. Krieg Angew. Chem. Internat. Edn. 1971 10 512.5 0 8 C. S. Cundy and H. Noth J. Organometallic Chem. 1971 30 135. 5 0 9 A. R. Kane and E. L. Muetterties J. Amer. Chem. SOC. 1971 93 1041. 5 1 0 W. R. Kroll and G. B. McVicker Chem. Comm. 1971 591. 5 1 1 A. T. T. Hsieh and M. J. Mays Inorg. Nuclear Chern. Letters 1971 7 223. A. T. T. Hsieh and M. J. Mays Chem. Comm. 1971 1234. 5 1 3 W. R. Robinson and D. P. Schussler J . Organometallic Chem. 1971 30 C5. 5 1 4 P. D. Cradwick J. Organometallic Chem. 1971 27 251. 5 1 5 E. H. Brooks and R. J. Cross Organometallic Chem. Rev. 1971 A6 227 Transition-metal Carbonyl Organometallic and Related Complexes 48 1 ing.’ l 6 The insertion of photochemically decarbonylated species into silicon-hydrogen bonds M(C0) + X,SiH 2 M(SiX,)H gives a new general route to metal silyls; obtained in this way are cis-(C1,Si)-(H) (OC),Cr( z-C6H6) cis-(C1,Si) (H) (OC),Mn(z-C,H,) cis-(OC),Fe(SiCl,)H cis-(OC),Fe(SiPh,)H (n-C,H ,)Co(CO) (SiCl,)H and cis-(Ph,Si) (H) (OC),Mn (n-C,H,Me).’ (Me,N),Ti.GePh has been prepared from (Me,N),TiBr and LiGePh,.”’ In (z-C,H,),Zr(Cl)SiPh, the Zr-Si bond is unexpectedly long (281 pm).’I9 Reaction of trialkyl phosphites with (OC),MnSiPh gives under mild conditions, products RCOMn(CO),[P(OR),] ; a possible mechanism is nucleophilic dis-placement of [Mn(CO),]- by phosphite from silicon.520 The reaction of (n-C,H,)Mn(CO),(SiPh,)H with phosphine ligands gives products (n-C,H,)-Mn(CO),PR ; the rate-determining step is reductive elimination of the ~ilane.’~’ Reaction of tetracarbonylferrate( - 2) with Me Sic1 gives dimeric [(Me,Si),-Fe(CO),] which with HCl gives [(Me,Si)(H)Fe(CO),] ; these are assigned probable structures (95a) and (95b) respectively and the possibility of undetected OR I Fe(CO) SiMe, (95) (a) R = SiMe, (b) R = H complexity in other products is pointed out.’, Fe(CO),(GeH,) has been prepared by a similar reaction.,, Hexamethylditin reacts with Fe(CO) to give (OC),Fe(SnMe,) ; (n-C5H5)Co(C0) gives not only the analogous (n-C,H,)-Co(CO)(SnMe,) but also a species M~,S~[CO(CO)(~-C,H,)]~ the i.r.spectrum of which indicates the existence of cisoid and transoid isomers; the rhodium analogue behaves similarly.524 The species (OC),Fe[SiMe,],[CO]Fe(CO) is fluxional.525 Silicon germanium tin and lead derivatives of type R,MFe(C0)2-5 1 6 ( a ) B. A. Goodman R. Greatrex and N.N . Greenwood J. Chem. SOC. ( A ) 1971, 1868; ( b ) S. R. A. Bird J. D. Donaldson A. F. Le C. Holding B. J. Senior and M. J. Tricker ibid. 1971 1616; (c) W. R. Cullen J. R. Sams and J. A. J. Thompson Inorg. Chem. 1971 10 843. 5 1 7 W. Jetz and W. A. G. Graham Inorg. Chem. 1971 10 4. 5 1 8 H. Burger and H.-J. Neese J. Organometallic Chem. 1971 32 223. 5 1 9 K. W. Muir J . Chem. SOC. ( A ) 1971 2663. 5 2 0 E. P. Ross R. T. Jernigan and G. R. Dobson J. Inorg. Nuclear Chem. 1971 33, 3375. 5 2 1 A. J. Hart-Davis and W. A. G . Graham J. Amer. Chem. SOC. 1971 93,4388. 5 2 2 M. A. Nasta and A. G. MacDiarmid J. Amer. Chem. SOC. 1971 93 2813. 523 S. R. Stobart Inorg. Nuclear Chem. Letters 1971 7 219. 5 2 4 E. W. Abel and S. Moorhouse Inorg. Nuclear Chem. Letters 1971 7 905.5 2 5 D. Kummer and J. Furrer Z. Nuturforsch. 1971 26b 162 482 P. S. Braterman (N0)L have been prepared (L = e.g. Ph,P PhEt,As or CO); i.r. evidence indi-cates a trigonal-bipyramidal structure with M and L axial and NO equatorial.526 Photochemical decarbonylation of [(n-C,H,)Fe(CO),],SiPh the tin analogue, and [(OC),Co],GePh leads to products of type (96).527 0 II / \ P h P h (96) (a) m = (rr-C,H,)Fe(CO) M = Ge (b) m = (rr-C,H,)Fe(CO) M = Sn (c) m = (OC),Co M = Ge The n.m.r. spectra of mixtures of (n-allyl)Pd(PPh,)Cl and tin@) chloride show that insertion of SnCI into the metal-chlorine bond is rapid and reversible.528 The disproportionation of methylsilicon hydrides is catalysed by (Et,P),PtCl ; in the presence of diphenylacetylene PhC CPh.SiMe,-CPh CPh-SiMe is formed indicating the existence of Pt SiMe complexes as intermediate^.^,^ Platinum-silicon and platinum-germanium bonds are formed by hydrogen elimination between trans-(Et,P),Pt(H)X and halogenosilanes or halogeno-germanes MH4-,X,.Oxidative addition of MH,X (M = Si or Ge; X = C1 Br, or I) to trans-(Et,P),PtI gives (Et,P),Pt(MH,X)(H)I ; this slowly loses hydrogen to give trans-( Et 3P)2 Pt( MHX1)l. tram-( E t ,P),Pt( SiH ,Cl)Cl reacts with dimethyl-amine to give the SiH,NMe derivative but HCI attacks the silicon-hydrogen bonds to give (Et3P)2Pt(CI)(SiC13).530 Platinum-metalloid bonds are also formed by the reaction of complexed Pt" halides with (Me,Si),Hg or (Me,Ge),Hg. Platinum-tin bonds may be formed from trimethylstannane either by oxidative addition to Pt' or by displacement of trimethylsilane from trimethylsilyl com-pounds.Pt'" compounds can be formed by oxidative addition of trimethyl-stannane to (dppe)Pt(SnMe,) . 5 3 The compound formulated by earlier workers as (Et3P),Pt(OH)GePh3 has been characterized crystallographically as cis-(E t P) Pt (P h) (GeP h OH). , 5 2 6 ( a ) M. Casey and A. R. Manning J . Chem. SOC. ( A ) 1971 256; ( b ) A. J. Cleland, S. A. Fieldhouse B. H. Freeland and R. J. O'Brien Chem. Comm. 1971 155; ( c ) A. J. Cleland S. A. Fieldhouse B. H. Freeland C. D. M. Mann and R. J. O'Brien, J . Chem. SOC. ( A ) 1971 736. 5 2 7 A. J. Cleland S. A. Fieldhouse B. H. Freeland and R. J. O'Brien J . Organometallic Chem. 1971,32 CIS. 5 2 8 M. Sakakibara Y. Takahashi S.Sakai and Y. Ishii J . Organometallic Chem., 27 139. 5 2 9 K. Yamamoto H. Okinoshima and M. Kumada J . Organometallic Chem. 197 C31. 530 J. E. Bentham S . Cradock and E. A. V. Ebsworth J . Chem. SOC. ( A ) 1971 587 5 3 1 A. F. Clemmit and F. Glockling J. Chem. SOC. ( A ) 1971 1164. 532 R. J. D. Gee and H. M. Powell J . Chem. SOC. ( A ) 1971 1956. 971, 27 Transition-metal Carbonyl Organometallic and Related Complexes 483 Group V.-Dinitrogen Complexes. The preparation of such complexes has been reviewed,', as has the development of an organometallic system for nitrogen fixation.', The system (n-C5HS),TiC1,-sodium naphthalenide resembles nitrogenase not merely in reducing N2 to amines but also in the reduction of KCN and C6H,,NC to methane.535 It must however be remembered that lithium naphthalenide can reduce nitrogen in the absence of any transition metal.536 (C6H6)MO(PPh,),H reacts reversibly363 with N to give [(C,H,)MoPPh,],N ; the NN frequency (Raman not i.r.) is at 1910 cm- '.Reduction of MoCl,L in THF with sodium amalgam under nitrogen gives Mo(N,),L (L = e.g. PMePh, PMe,Ph).537 The crystal structure of ReCI(N2)-(PMe,Ph) has been determined; chlorine and N2 are mutually trans.538 Treatment of (n-C,H,)Fe(dmpe)I with TlBF in acetone gives (n-C5HS)-Fe(dmpe)(acetone)+ ; this reacts539 with nitrogen to give nitrogen-bridged [(n-C,H,)Fe(drnpe)],N ; v(NN) (Raman not i.r.) is at 2054 cm- '. A dinuclear dinitrogen iron complex is also formed by the Pr'MgX reduction of (Ph,P),-FeC1 ; HC1 causes reduction of the co-ordinated N to hydra~ine.'~' Species L,Co(H)(N,) are formed from cobalt(I1) or cobalt(u1) acetylacetonates under nitrogen in the presence of the ligand L by organoaluminium reduction.On going from L = PPh to L = PBu", the nitrogen-nitrogen stretching frequency predictably falls. The complex undergoes reversible reaction with hydrogen to give L,CoH ; the reaction with CO iodolysis thermolysis and acidolysis are irrever~ible.~~' Sodium metal reduction (in THF under N,) of (Ph3P),CoCl gives [(Ph,P),Co],N and [(Ph,P),CoN,]-. This last is a nucleophile reacting with (PhEt,P),CoCI to give (P~E~,P),CON,CO(PP~~).~~~ The i.r. intensity of the nitrogen-nitrogen stretch in (Ph,P),Ir(N,)Cl is less than that of v(C0) in the carbonyl analogue ; this is taken to show that N is a poorer n - a c c e p t ~ r .~ ~ ~ Co-condensation of nickel vapour with N in argon gives NiN, Ni(N,), and oligomeric species. 544 Nitrosyl Complexes. The crystal structure of (C5H,),Cr,(NO),NH contains two (n-CsHs)Cr(NO) groupings held together by bridging NH, bridging NO, and a direct metal-metal bond.',' The proton n.m.r. spectrum of Mo(NO),-5 3 3 ( a ) G . J. Leigh Prep. Znorg. Reactions 1971 7 165; (6) R. W. Parry Inorg. Syntheses, s 3 4 E. E. van Tamelen Accounts Chem. Res. 1970 3 361. 5 3 5 E. E. van Tamelen H. Rudler and C. Bjorklund J . Amer. Chem. SOC. 1971 93, 3526. 536 M. E. Volpin A. A. Belyi V. B. Shur N. A. Katkov I. M. Nekaeva and R. V. Kudryavtsev Chem. Comm. 1971 246. 5 3 7 T. A. George and C. D. Seibold J. Organometallic Chem. 1971 30 C13.538 B. R. Davis and J. A. Ibers Inorg. Chem. 1971 10 578. 5 3 9 W. E. Silverthorn Chem. Comm. 1971 1310. 5 4 0 Yu. G. Borodko M. 0. Broitman L. M. Kachapina A. E. Shilov and L. Yu. Ukhin, Chem. Comm. 1971 1185. 5 4 1 A. Yamamoto S. Kitazume L. S. Pu and S. Ikeda J. Amer. Chem. SOC. 1971 93, 371. 5 4 2 M. Aresta C. F. Nobile M. Rossi and A. Sacco Chem. Comm. 1971 781. 5 4 3 D. J. Darensbourg and C. L. Hyde Inorg. Chem. 1971 10 431. 5 4 4 J. K. Burdett and J. J. Turner Chem. Comm. 1971 885. ' 4 5 L. Y . Y. Chan and F. W. B. Einstein Acra Cryst. 1970 B26 1899. 1970 12 1 484 P. S . Braterman (S2CNMe2)2 at 300K is as expected for a &-octahedral complex but inter-conversion of methyl groups is detectable by n.m.r. at temperatures above 370 K.546 The compound (n-C,H,)Mn(NO,) [NO],Mn(NO)(n-C,H,) has the unusual structure (97).547 0 YZ1 y o (97) (distances in pm) Treatment of species Ru(NO)C13L2 with ethanolic KOH in the presence of ex-cess L gives RuH(NO)L ; H and NO are trans in a trigonal-bipyramidal environ-ment.548 In the PPh complex the system Ru-N-0 is linear and the ruthen-ium-nitrogen bond short (180 pm) despite the low (1640 cm-') NO stretching waven~mber.,~~ The crystal structure of [Os(OH)(NO),(PPh,),] +PF6-shows the presence in the square-pyramidal cation of both linear (equatorial) and bent (axial) NO The complex RUCI('~NO)(PP~,)~ reacts with 14NOPF6 to give partly labelled [RuCl(NO),(PPh,),]+.This shows four NO stretching bands in the i.r. spectrum; the implication is that the two 'distinct' (equatorial and axial) NO groups interconvert readily.,,' NO in [Ru(NH,)~-NO],+ reacts with H,NOH to give Ru(NH,),N202+ and with hydrazine and NH to give the dinitrogen complex.552 Treatment of Co,(CO) with excess NO in hexane gives the chain polymer [-Co(NO),.N(O)O-1,; there is evidence for a dimer in solution.553 The reaction between tris(tripheny1phosphine)cobalt nitrosyl and NO in aromatic hydrocarbons at room temperature has been shown by quantitative product analysis to obey the equation554 (Ph,P),CoNO + 7N0 + Co(N0)2PPh,(N02) + 2N20 + $N2 + 2Ph3P0 The crystal structures of tr~ns-[CoCl(NO)(en),]ClO~~~ and [Co(NO)(NH,),] C:,556 reveal the presence of NO- with CoNO angles of ca.120" ; the determina-tion in the latter case involved analysis of counter data for a twinned crystal.The 5 4 6 R. Davis M. N. S. Hill C. E. Holloway B. F. G. Johnson and K. H. Al-Obaidi, 5 4 7 J. L. Calderon F. A. Cotton B. G. DeBoer and N. Martinez Chem. Comm. 1971, 5 4 8 S . T. Wilson and J. A. Osborn J. Amer. Chem. SOC. 1971,93 3068. 5 4 9 C. G. Pierpont A. Pucci and R. Eisenberg J. Amer. Chem. SOC. 1971,93 3050. 5 5 0 J. M. Waters and K. R. Whittle Chem. Comm. 1971 518. 5 5 1 J. P. Collman P. Farnham and G. Dolcetti J. Amer. Chem. SOC. 1971 93 1788. 5 5 2 F. Bottomley and J. R. Crawford Chem. Comm. 1971 200. 5 5 3 C. E. Strouse and B. I. Swanson Chem. Comm. 1971 5 5 . 5 5 4 M. Rossi and A. Sacco Chem. Comm. 1971 694. 5 5 5 D. A. Snyder and D. L. Weaver Znorg. Chem. 1970,9 2760. 5 5 6 C. S. Pratt B. A. Coyle and J. A. Ibers J . Chem.SOC. ( A ) 1971 2146. J . Chem. SOC. ( A ) 1971 994. 1476 Transition-metal Carbonyl Organometallic and Related Complexes 485 strong trans influence of NO- is seen in the length (257pm) of the cobalt-chlorine bond and even more dramatically in the absence of a sixth ligand e.g. in (98) in which the Co-N distances are 189 pm to the Schiff-base nitrogens and 0 / (98) 182 pm to nitr~syl."~ Relatedly IrC1,(NO)(PPh,)2558 and IrI(Me)(NO)-(PPh3)25s9 are square-pyramidal complexes of Ir"' and NO- with IrNO angles of ca. 120" and Ir-N bond lengths of ca. 192pm; but [IrH(NO)(PPh,),]+ C10,- is a complex of trigonal-bipyramidal Ir'. H and NO are axial and the Ir-N distance is 168 Other Nitrogen-bound Ligands. In complexes (7c-CSHs)Mn(CO),NC-C6H,-p-Y, there are linear correlations between the change in v(CN) on complexing the CO stretching parameter the ring-proton chemical shift the maximum in the U.V.spectrum and the cP constant of Y.s61 The i.r. spectra of species [Mn(CO),XI2-NC(CH,),,CN show them to be halide-bridged with nitrogen acting as a o-donor ; the earlier suggestion of n-bonding to C-N is incorrect.562 One ligand CO is converted into NCO- in the reactions of M(CO)6 with NH,OH or NH,Cl (M = Cr Mo or W),563 of [Re(CO),]+ with azide or h y d r a ~ i n e ~ ~ and of [(n-C5H,)Fe(C0),PPh3] + with azide or hydrazine. The latter reaction with azide is first-order in each component consistent with rate-determining nucleophilic attack by N - on ligand CO followed by rearrangement with loss of N ;565 however such an additiondegradation mechanism cannot operate in the attack of labelled isocyanate on [(7c-CsH5)Fe(CO),]+ which leads to labelled (n-C,H,)Fe(CO),NC0.566 Reaction of Mn(CO),Br with a large excess of azide (smaller amounts of azide give isocyanates) gives the anion [(OC),Mn(N,),Mn(CO),] - in which the azides are bridge-bonded at one nitro-gen the MnNMn angle is 89" and the manganese-manganese distance is 289 pm.This would appear to indicate some metal-metal bonding though the 18-electron rule does not require this567 (compare ref. 46). Reaction of metal dimethylamide 5 5 7 R. Wiest and R. Weiss J . Organometallic Chem. 1971 30 C33. 5 5 8 D. M. P. Mingos and J. A. Ibers Inorg. Chem. 1971 10 1035. 5 5 9 D. M. P. Mingos W. T. Robinson and J. A. Ibers Inorg. Chem. 1971 10 1043.5 6 0 D. M. P. Mingos and J. A. Ibers Inorg. Chem. 1971 10 1479. 5 6 1 M. Herberhold and H. Brabetz Chem. Ber. 1970 103 3896 3909. 5 6 2 J. G. Dunn and D. A. Edwards Chem. Comm. 1971,482. 563 W. Beck and B. Lindenberg Angew. Chem. Internat. Edn. 1970 9 735. 5 6 4 R. J. Angelici and G. C. Faber Inorg. Chem. 1971 10 514. 5 6 5 M. Graziani L. Busetto and A. Palazzi J . Organometallic Chem. 1971 26 261. 5 6 6 L. M. Charley and R. J. Angelici Inorg. Chem. 1971 10 868. 5 6 7 R. Mason G. A. Rusholme W. Beck H. Englemann K. Joos B. Lindenberg and H. S. Smedal Chem. Comm. 1971,496 486 P. S . Braterman complexes with benzophenoneimine gives (n-C,H,),Zr(NCPh,) and Ti(NCPh,) .568 (CF,),CNLi(RLi) reacts with metal halides to give (Z'CgHg)2-Ti(Cl)R (Ph,P),RhR cis-(PhMe,P),PtR, and trans-(Ph,P),Pt(R)H ; this last rearranges to (Ph,P),PtC(CF,),NH.' 69 Bridged species [Fe(CO),] [NCR,] , result from the reaction of Fe(CO),I with R,CNLi.570 Diazonium salts substitute one CO on each molybdenum of [Mo,(CO),,-(OH),I4- ; the product is cleaved by bipyridyl to give (bipy)Mo(OH)(CO),-(N,Ar).571 Species [(Ph,P),PtNNC,H,R] + result from the attack of [p-R.C,H,N,]+ on (Ph,P),Pt ; these react with H to give [(Ph,P),PtH]+, C,H,R and N, with 0 in methanol to give [(Ph3P)2Pt(OH)]22 + RC,H,OH, and N and with acids (reversibly) to give (Ph,P),Pt.NH N.C6H4R2 +.572 How-ever trans-Ir(CO)CI(PPh,) reacts with p-F.C6H,N,BF4 to give the Ir' (or Ir'") complex (99).'73 I Ar-N N-Ar c) Ar-N \+/ I IrL,(CO) (99) Reaction of azobenzene with Ni" complexes gives species L,Ni(PhNNPh) ; for L = Bu'NC it has been shown crystallographically that both nitrogens are bonded to the metal that the ligand is in the cis conformation and that the phenyl-nitrogen bonds lie out of the NiNN plane.The Bu'N-C stretching frequency shows diazobenzene to be more electron-withdrawing than fumaroni-trile but less so than tcne or 0,. 74 Bis(trifluoromethy1)diazomethane reacts with a range of Ni' Pd' and Pto complexes to give products L,MC(CF,),-N.-N=C(CF,),; the crystal structure of the (Ph,P),Pt compound has been determined.' The strong visible solvatochromism of the di-imine complex m CxN CHCH N(Cx)Mo(CO) correlates with unusually marked solvent de-pendence of CO stretching frequencies and is thus a ground-state rather than an excited-state effect.Successive replacement of CO by Ph,P reduces and finally reverses the solvatochromism; it is inferred that the donor orbital is localized 5 6 8 5 6 9 5 7 0 5 7 1 5 7 2 5 7 3 5 7 4 5 7 5 M. R. Collier M. F. Lappert and J. McMeeking Inorg. Nuclear Chem. Letters, 197 1 7 689. B. Cetinkaya M. F. Lappert and J . McMeeking Chem. Comm. 1971 215. M. Kilner and C. Midcalf Chem. Comm. 1971 944. F. J. Lalor and P. L. Pauson J . Organometallic Chem. 1970 25 CS1. S. Cenini R. Ugo and G. La Monica J . Chem. SOC. ( A ) 1971 3441. F. W. B. Einstein A. B. Gilchrist G. W. Rayner-Canham and D. Sutton J . Amer. Chem. SOC. 197 1 93 1826. (a) H.-F. Klein and J. F. Nixon Chem. Comm. 1971 42; (b) S. Otsuka T. Yoshida, and Y. Tatsuno ibid.1971 67; (c) R. S. Dickson J. A. Ibers S. Otsuka and Y. Tatsuno J . Amer. Chem. SOC. 1971 93 4636. J. Clemens R. E. Davis M. Green J. D. Oliver and F. G. A. Stone Chem. Comm., 1971 1095 Transition-metal Carbonyl Organometallic and Related Complexes 487 mainly on Mo in the tetracarbonyl complex but on substitution becomes in-creasingly localized on the nitrogen ligand.s76 It is relevant that in Bu'N CHCH N(Bu')Mo(CO) unlike most di-imine complexes the I3C n.m.r. signal of the bridging carbons shows a high-field shift.s77 In the complexes [(bipy),Cr]"+ (n = &3) the metal-nitrogen frequency has been identified using ,'Cr and ',Cr isotopic labelling; it varies little with the charge on the complex, and is therefore a poor indicator of the actual oxidation state of the In complexes (Ar2CNCAr,)M(C0),(n-CSHs) (M = Mo or W Ar = p-tolyl), the methyl group temperature-variable n.m.r.spectra show the nitrogen ligand to be bonded a~ymmetrically.~~~ Diaryltriazenido (ArNNNAr ; Ar = e.g. p-tolyl) complexes of a variety of metals have been prepared ; the ligand may be uni- or bi-dentate."' Reaction of (n-C,H,)Co(CO) with NO in the presence of norbornene gives ( 1oO).s8 The free radical diphenylpicrylhydrazyl [Ph,N-NC,H,(NO,),] reacts with (Ph,P),Pt to give Ph2NPt(PPh,),C6H,(N02)3 .582 Phosphorus-bound and Related Ligands. When treated with PF tetra-allyltan-talum gives (allyl)Ta(PF,) and hexadiene.' 8 3 (PhH,P),Mo has been prepared by the reduction of MoCI,(THF) in the presence of the phosphine ; Mo(N,),-(dppe) and a species that may be (PhMe,P),Mo are prepared similarly.s84 Displacement of co-ordinated cycloheptene by AsF gives (n-C,H,)Mo(CO),-AsF the first trifluoroarsine complex.The CO frequencies and the ionization potential are higher than in the PF analogue perhaps as a result of the higher I.P. and poorer donor power of AsF itself.s85 Species { [(n-C,H,)Fe(CO),],-MX,) + (n-C,H,)Fe(CO),MX, and [(n-C,H,)Fe(CO),],SbX are obtained by the reaction of ( ~ C - C H ~ ) F ~ ~ ( C O ) ~ with MX (M = As or Sb; X = C1 or Br).586 576 H. tom Dieck and I. W. Renk Angew. Chem. internat. Edn. 1970,9,793. 577 C. Tanzer R. Price E. Breitmaier G. Jung and W. Voelter Angew. Chem. Internat. 5 7 8 J. Takemoto B. Hutchinson and K. Nakamoto Chem. Comm. 1971 1007. 5 7 9 H. R. Keable and M. Kilner Chem.Comm. 1971 349. Edn. 1970 9 963. S. D. Robinson and M. F. Uttley Chem. Comm. 1971 1315. H. Brunner and S. Loskot Angew. Chem. Internat. Edn. 1971 10 515. "' W. Beck K. Schorpp and K. H. Stetter 2. Naturforsch. 1971 26b 684. 583 Th. Kruck and H.-U. Hempel Angew. Chetn. internat. Edn. 1971 10 408. 5 8 4 J. Chatt and A. G. Wedd J . Organometallic Chem. 1971 27 (215. 5 8 5 J. Miiller and K. Fended Angew. Chem. Internat. Edn. 1971 10 418. 5 8 6 W. R. Cullen D. J. Patmore J. R. Sams M. J. Newlands and L. K. Thompson, Chem. Comm. 1971 952 488 P. S . Braterman The salt {[(n-C,H5)Fe(C0)2]3SbCl)+FeC14- is obtained by reaction of [(n-C,H,)Fe(CO),] - with SbCl ; the co-ordination around Sb is approximately tetrahedral with an iron-antimony distance of 254 pm.587 The optically active complex [Ph,(neomenthyl)P],RhCl is a catalyst for the asymmetric reduction of 01efins.~~~ (Ph,P),RhCl reacts with white phosphorus at 200 K to give (Ph3P)2RhC1(P4).589 Nickel@) salts are reduced by trimethyl-phosphine in basic solution giving (Me,P),Ni and Me,P0.590 The sterically demanding ligand (o-bipheny1)phosphine (L) reacts with Ni(acac) in the presence of trimethylaluminium to give NIL ; this can add a further less-demanding, ligand.591 The substitution of PF by CxNC in Ni(PF3)4 and the Pd and Pt analogues is dissociative ; the order of metal-phosphorus bond strengths is Ni > Pd < Pt.592 L,PtCO (in which carbonate is bidentate; L = PPh,, AsPh, or PMePh,) is a convenient precursor for the species L,Pt.593 Treatment of complexes (R,P),PtB,H (ref.509) with phosphines gives species (R,P),Pt. (Et,P),Pt is an unusually strong nucleophile inserting into the Ph-X bond of benzonitrile and chlorobenzene to give (Et,P),Pt(Ph)X.594 N.m.r. spectroscopy shows (Ph,MeP),Pt in solution to have lost one ligand ; exchange is fast above 245 K. There is no evidence for phosphine loss from (PhMe,P)4Pt.595 The reduction of AuNO with controlled amounts of borohydride in the pre;ence of tri-(p-toly1)phosphine gives AU,(tOl,P),(NO,) in which each peripheral gold atom is bonded to three other peripheral metal atoms and to the one in the centre of the cluster.s96 Oxygen-group Ligands.-The dioxygen complex RuCl,(AsPh,),(O,) is de-scribed as paramagnetic.597 Reaction of the complexes M(CO)L,+ with air (M = Rh or Ir; L = PhMe,P or PhMe,As) gives species M(02)L4+ ; these are also accessible from the reaction of [(cod)MCl] with methanol and air.s98 The dioxygen adduct of (Ph,P),RhCl obtained with one mole of CH2C12 of crystallization has the unexpected structure ( 101).599 The affinity of species trans-Ir(CO)Cl(PR,) for dioxygen generally increases with the donor power of the phosphine but is also highly sensitive to steric factors.600 Dibenzylidenacetone (dba PhCH CHCOCH CHPh) forms an air-stable soluble complex (dba),Pt, 5 8 7 Trinh-Toan and L.F. Dahl J. Amer. Chem. SOC. 1971 93 2654. 5 8 8 J. D. Morrison R. E. Burnett A. M. Aguiar C. J. Morrow and C. Phillips J. Amer. 5 8 9 A. P. Ginsberg and W. E. Lindsell J. Amer. Chem. SOC. 1971 93 2082. 5 9 0 H.-F. Klein and H. Schmidbaur Angew.Chem. Internat. Edn. 1970 9 903. 5 9 1 M. Englert P. W. Jolly and G. Wilke Angew. Chem. Internat. Edn. 1971 10 77. 5 9 2 R. D. Johnston F. Basolo and R. G. Pearson Inorg. Chem. 1971 10 247. 5 9 3 D. M. Blake and R. Mersecchi Chem. Comm. 1971 1045. 5 9 4 D. H. Gerlach A. R. Kane G. W. Parshall J. P. Jesson and E. L. Muetterties J. Amer. Chem. SOC. 1971 93 3543. 5 9 5 H. C. Clark and K. Itoh Znorg. Chem. 1971 10 1707. 5 9 6 P. L. Bellon F. Cariati M. Manaserro L. Naldini and M. Sansoni Chem. Comm., 1971 1423. 5 9 7 M. M. Taqui Khan R. K. Andal and P. T. Manoharan Chem. Comm. 1971 561. 5 9 8 L. M. Haines and E. Singleton J. Organornetallic Chem. 1971 30 C81. 5 9 9 M. J. Bennett and P. B. Donaldson J. Amer. Chem. SOC. 1971 93,3307. 6oo ( a ) G .R. Clark C. A. Reed W. R. Roper B. W. Skelton and T. N. Waters Chem. Cornm. 1971 758; (6) L. Vaska and L. S. Chen ibid. 1971 1080. Chem. SOC. 1971 93 1301 Transition-metal Carbonyl Organometallic and Related Complexes 489 in which the ligand n.m.r. and v(C=C) spectra are little changed ; the CO stretch-ing band is lost and it is suggested that co-ordination is through the Ph,P -PPh, C ' I PPh, (101) CO n-system.601 Carbonyl perchlorate complexes O,C~OCO(CO)~(PP~,)~, 03C10Rh(CO)(PPh,)2 and O3C1OIr(CO)(PPh3) have been prepared from AgC10 and the appropriate chloride.602 Reaction of Rh(dmpe),+ C1- and Ir(dppe) 'C1- with elemental sulphur gives complexes of S2 analogous to the known complexes of 0,; the iridium-diselenium complex has also been prepared.603 (n-C5H,),VC12 reacts with S52 - to give (n-C5H5)2VS5 the e.s.r.spectrum of which is as expected for V'" ; the reaction with Ses2- is similar.604 Species (H2S)Pt(PPh3) and (H2Se)-Pt(PPh,) have been de~cribed.~" The phosphine sulphide complex Ph,PSCr(CO) has been obtained photochemically.606 Dioxygen complexes in general react with SO2 to give sulphate complexes but the related reaction of SO2 complexes with O2 is more specific and IrCl(SO,)(CO)(PPh,) does not SO2 reacts with (n-C5H5)2Fe2(C0)4 to give the triply bridged species (n-C5H ,),TiMeCl undergoes SO2 insertion into the titanium-methyl bond ; but the phenylzirconium analogue reacts to give polymeric [C5H5Zr(02Sph)-(02SC5H5)C1] .609 The SO2 insertion product (n-C,Me,)Fe(CO),S(o),.-CH2CH CHPh is sulphur-bonded,610 as is (7t-C5H5)Fe(C0)2S(0)2C6F5 (from nu-cleophilic atta~konC~F,SO,Cl);~' ' Ir(CO)(PPh,)202S-p-C6H,Me is 0-bonded, as is the methyl iodide adduct but the CO and O2 adducts rearrange to give the S-bonded isomer.6 Maleonitriledithiolate (mnt) complexes of tetramethyl-cyclobutadiene-nickel and -palladium C,Me,M(mnt) have been prepared ; (7r-C5 H5)Fe(CO),Fe(n-C,H5) [ S( O),],Fe( n-C5H ,)Fe(n-C5H 5)(C0)2 .608 6 0 1 K.Moseley and P. M. Maitlis Chem. Comm. 1971 982. 6 0 2 J. Peone jun. and L. Vaska Angew. Chem. Internat. Edn. 1971 10 511. 6 0 3 A. P. Ginsberg and W. E. Lindsell Chem. Comm. 1971 232. 604 H. Kopf A. Wirl and W. Kahl Angew. Chem. Internat. Edn. 1971 10 137. 6 o s 6 0 6 E. W. Ainscough A. M. Brodie and A. R. Furness Chem. Comm. 1971 1357. 607 J.Valentine D. Valentine jun. and J. P. Collman Znorg. Chem. 1971 10 219. 6 0 8 D. S. Field and M. J. Newlands J. Organometallic Chem. 1971 27 221. 6 0 9 P. C. Wailes H. Weigold and A. P. Bell J. Organometallic Chem. 1971,33 181. 6 1 0 M. R. Churchill and J. Wormald Znorg. Chem. 1971 10 572; R. J. Angelici unpub-"' 6 1 2 C. A. Reed and W. R. Roper Chem. Comm. 1971 1556. R. Ugo G . La Monica S . Cenini A. Segre and F. Conti J. Chem. SOC. ( A ) 1971 522. lished results cited therein. M. I. Bruce and A. D. Redhouse J . Organometallic Chem. 1971 30 C78 490 P. S. Braterman surprisingly the carbon-carbon stretching frequency is said to be low as appro-priate for the thioketone state of the ligand.613 Compounds with Bonds between Transition Metals.-Metal-metal bond lengths and radii in transition organometallics have been re~iewed.~ l4 Er[Co(C0),J3-4THF has been prepared by erbium metal displacement of mercury,615 and U[Mn(CO),] by attack of Mn(CO) - on UCI .616 Dimethylamine elimination from (n-C,H,),TiNMe gives the compound (n-C5H,)2TiMo(CO)3(n-C5H5); this gives the expected magnetic moment for Ti"' but normal ring-proton n.m.r.signals are r e p ~ r t e d . ~ l 7 Molybdenum to manganese donation followed by metallation of a co-ordinated ring is thought to be responsible for the formation of (102) from MeMn(CO) and (~c-C~H,),MOH,.~'* The i.r. spectrum of (n-C,H,)Fe(CO) [CO],Ni(n-C,H,) is consistent with a nearly planar Fe[CO],Ni ring in contrast to the puckered ring of [(n-C,H,)Ni],[CO] .619 (n-C,H,)-Fe(CO),Co(CO) exists in one non-bridged and two bridged forms ; the ruthenium analogue is non-bridged only.620 The complexes Ph,PAuFe(CO),NO and Ph,PAuCo(CO) ionize reversibly in donor solvents but substitution of CO by phosphines makes the metal carbonyl anion too poor a leaving group for this to occur.62 In (Ph,P)AuCo(CO) and the related silver complex with (o-C,H,AsMe,),AsMe the transition metal occupies an apex of the cobalt ligand bipyramid and the equatorial CO groups are bent towards it.622 Structural and spectroscopic evidence both indicate the existence of some dative Mo + Ti" o-bonding in (n-C5H,),Ti(SMe)2Mo(CO)4 and related species ;623 but in such electron-rich systems as (n-C5H5)W(SPh)2M(C0)4623b and (dppe)-M'(SR)M(CO) (M' = Pd or Pt; M = Cr Mo or W)624 the bis(thio1ato)metal 6 1 3 6 1 4 6 1 5 6 1 6 6 1 7 618 619 6 2 0 6 2 1 6 2 2 6 2 3 6 2 4 E.J. Wharton Inorg. Nuclear Chem. Letters 1971 7 307. B. P. Biryukov and Yu. T. Struchkov Russ. Chem. Rev. 1970,39,789. R . S . Marianelli and M. T. Durney J . Organornetallic Chern. 1971 32 C41. R. L. Bennett M. I. Bruce and F. G. A. Stone J . Organornetallic Chern. 1971 26, 355. M. F. Lappert and A. R. Sanger J . Chem. SOC. ( A ) 1971 1314. R. Hoxmeier B. Deubzer and H. D. Kaesz J . Amer. Chem. Soc. 1971 93 536. P. McArdle and A. R. Manning J . Chem. SOC. ( A ) 1971 717. A. R. Manning J. Chem. SOC. ( A ) 1971 2321. M. Casey and A. R. Manning J. Chem. SOC. ( A ) 1971 2989. T. L. Blundell and H. M. Powell J . Chem. SOC. ( A ) 1971 1685. ( a ) T. S. Cameron C.K. Prout G. V. Rees M. L. H. Green K. K. Joshi G. R. Davies, B. T. Kilbourn P. S. Braterman and V. A. Wilson Chern. Comm. 1971 14; (b) G. R. Davies and B. T. Kilbourn J . Chern. SOC. ( A ) 1971 87; ( c ) P. S. Braterman V. A. Wilson and K. K. Joshi ibid. 1971 191. P. S. Braterman V. A. Wilson and K. K. Joshi J . Organometallic Chem. 1971 31, 123 Transition-metal Carbonyl Organometallic and Related Complexes 49 1 system co-ordinated to M(CO) acts as a simple ligand. Similarly (n-C5H5)2-Mo(SR) co-ordinates to Ni" PI' Pt" and Rh1,625 and also to Fe" and Co"; in the latter cases at least there is no metal-metal bond.626 The Nb" complex (n-C,H,),Nb(SMe) reacts with salts of Ni" Pd" and Pt" to give products [(n-C,H,),Nb(SMe),]2M(BF4)2 in which the Group VIII metal is tetrahedral ; thus these formally contain NbV and M'O.Again there is structural evidence for M" -+ NbV dative bonding,627 and there is physical evidence for Cu'+ TiIV donation in polymeric [(n-C,H,),Ti(SR),CuX] .628 The metal-metal bond in [(n-C,H,)Mo(SMe),] is hardly affected by a one-electron oxidation629 (con-trast ref. 452). A direct metal-metal b o d appears on structural evidence to be absent in the bridged species [(Me,SiCH,),Nb],[C(SiMe,)] ,630 but is presumed present in an acetate-bridged diamagnetic species [Pd,(C6H8)(OAc) ~AcOH], which has been isolated from the reaction mixture in the palladium(r1)-acetate-catalysed autoxidation of CLyclohexa- 1,4-diene.63 The dianions Hg[Cr(C0)5]22- and M[Fe(CO),]22- (M = Zn Cd or Hg) are obtained by insertion reactions of the Group I1 metal; their spectra show them to be linear.632 So on crystallographic evidence is Hg[Mn(CO),] (eclipsed; compare ref.44).633 In CdFe(CO), HgFe(CO) and species L,ZnFe(CO), and L,CdFe(CO) (where L is a nitrogen ligand) two highly covalent bonds to the Group I1 metal occupy cis positions in the iron co-ordination octahedron (the evidence comes from i.r. and Mossbauer spectro~copy).~~~ Equilibria have been demonstrated in aqueous solution between [Fe(C0),I2 -, [Fe(CO),H] - [HZnFe(CO),] + ZnFe(CO), [Zn2Fe(CO),I2+ and [HOZnFe-(CO)4]22 - (presumably the zinc-containing species are hydrated).635 Oxidative addition of Hg(GeMe,) to (Et3 P),Ir(CO)Cl gives (Et P),Ir(HgGeMe,)(GeMe,)-(C0)Cl; mild HCl acidolysis cleaves the germanium-mercury bond only to give (Et3P)21r(HgC1)(GeMe3)(CO)C1.636 Addition of PhHg-X (X = C1 or Br) to [Ni(CO),] is suggested as a step in the reaction of PhHgX and nickel carbonyl to give b e n ~ o p h e n o n e .~ ~ ~ 6 2 5 A. R. Dias and M. L. H. Green J . Chem. SOC. ( A ) 1971 1951. 6 2 6 ( a ) A. R. Dias and M. L. H. Green J . Chem. SOC. ( A ) 1971 2807; (b) T. S . Cameron 6 2 7 W. E. Douglas M. L. H. Green C. K. Prout and G. V. Rees Chem. Comm. 1971,896 6 2 8 P. S . Braterman and V. A. Wilson J. Organometallic Chem. 1971 31 131. 6 2 9 N. G . Connelly and L. F. Dahl J . Amer. Chem. SOC. 1970,92 7470. 630 F. Huq W. Mowat A. C. Skapski and G. Wilkinson Chem. Comm. 1971 1477. 6 3 1 J. M. Davidson Chem. Comm. 1971 1019. 6 3 2 H. Behrens H.-D. Feilner E. Lindner and D. Uhlig Z . Naturforsch. 1971 26b 990. 6 3 3 W. Cleggand P. J . Wheatley J . Chem. SOC. ( A ) 1971 3572. 6 3 4 ( a ) T. Takano and Y . Sasaki Bull. Chem. SOC. Japan 1971,44,431; ( b ) A. T. T. Hsieh, M. J. Mays and R. H. Platt J . Chem. SOC. ( A ) 1971 3296. 635 F. Galembeck and P. Krumholz J . Amer. Chem. SOC. 1971 93 1909. 6 3 6 K. A. Hooton J . Chem. SOC. ( A ) 1971 1251. 6 3 7 Y . Hirota M. Ryang and S. Tsutsumi Tetrahedron Letters 1971 1531. and C. K. Proct Chem. Comm. 1971 161

ISSN:0069-3022    

DOI:10.1039/GR9716800419

出版商:RSC    

年代:1971

数据来源: RSC

摘要:

16 Mechanisms of Inorganic Reactions By A. McAULEY Department of Chemistry University of Glasgow Glasgow GI2 800 The scope and format of the Report are similar to those of previous years with the restriction to the reactions of inorganic compounds in solution. References have been chosen as representative of areas where work is being currently under-taken with a view to general reader coverage since one of the Specialist Periodical Reports' is now devoted to this subject. 1 Electron Transfer Reactions Transition-metal Complex Ions.-The electron-transfer step in a redox reaction between two metal-ion complexes is the subject of continuing interest. The effect of non-bridging ligands on such processes has been discussed,2 the main influence of such groups both on oxidant and reductant being to change the overall free energy of the reaction and thereby to alter the activation free-energy.In the inner-sphere chromium(r1) reduction of thiocyanato- and isothiocyanato-pentamminecobalt(Ir1) complexes3 the former species are reduced at a much faster rate than the latter. The reaction path for (H3N)5CoSCN2+ involves both remote and adjacent attack whereas the reduction of (H,N),CoNCS2 + proceeds quantitatively uia the remote attack. The chromium(1n) product in the corre-sponding reaction of (H3N)&oNC02+ i.e. (H20)5CrOCN2+ is considered to undergo hydration to yield [(H20)5Cr02CNH2]2+.4 In the reduction of [(en),Co(SCH,CO,)] +,5 transfer of the mercaptoacetate group is involved to form [(H20)5Cr(SCH2C02H)]2+ which undergoes much more rapid ring closure than is observed in other chromium(II1) reactions.Relative rates of reaction with cobalt(rI1) complexes have been described in systems where two potential bridging ligands (on separate complexes) compete for the chromium(rI).6 For complexes of the type (H3N)5C~L2+ the relative rates are 2.75 1.89 1.51 : 1-00:0-88 for L = I- Br- Cl- F- and N3- respectively. When two dif-ferent halides are present in the same complex however e.g. cis- or trans-Co(en),BrCl+ the relative preference of Cr" for Br- over C1- is reduced from 'Inorganic Reaction Mechanisms' ed. J. Burgess (Specialist Periodical Reports), The Chemical Society London 1971 vol. 1. * J. E. Earley Progr. Znorg. Chem. 1970 13 243. C. Shea and A. Haim J. Amer. Chem. SOC. 1971,93 3055. R.J. Balahura and R. B. Jordan Znorg. Chem. 1971,10 198. R. H. Lane and L. E. Bennett Chem. Comm. 1971,491. M. C. Moore and R. N. Keller Znorg. Chem. 1971 10 747 494 A . McAuley 1.26 in the penta-ammine species to 1.14 and 1.00 for the cis- and trans-isomers. Alkylchromium(I1I) complexes are formed in the chromium(I1) reduction of organic radicals derived from isopropanol and ether (by hydrogen-atom abstraction using hydroxyl radicals). In general redox reactions of metal-ion complexes involve a single electron-transfer step but a two-electron inner-sphere reduction of (H,N),PtCl3 + by Cr" has been demonstrated :8 Cr" + Pt"' -P Pt" + CP"I CPCI + Cr" -+ Cr"U + Cr"' Absorbance changes in the europium(I1) reduction of isonicotinamidopenta-amminecobalt(rI1) show marked deviation from those expected for a reaction which is first order with respect to oxidant and reductant,' the electron-transfer reaction being radical-catalysed : H+ + Eu2+ + Co"'L -+ Co2+ + Eu3+ + HL' HL+ + Eu2+ $ Eu3+ + HL H+ + HL' + Co"'L - Co2+ + 2HL+ It is of interest that the reaction appears to be specific for this ligand with no comparable behaviour for either pyridine or nicotinamide.The oxidation of benzoatopenta-amminecobalt(II1) complexes by hydroxyl radicals has also been examined.' The reduction of dinuclear tetra-amminecobalt(Ir1) complexes containing p-amido- and either p-sulphato- or p-selenato-,' or p-oxalato-' ' bridging groups by metal ions (V" and Cr") has been investigated. Two-stage reactions are ob-served each involving the reduction of a cobalt centre and in reductions involv-ing chromium(Ir) dinuclear cobalt(m~hromium(m) intermediates have been characterized.In the reaction of iron@) with multidentate cobalt(1n) complexes,' cis-or-Co(trien)Cl,+ and cis-ct-Co(trien)OH2C12 + the rate of reduction decreases with increasing chelation. Solvation is important and a model has been derived which compares the ligand-field strength of the group trans to the bridging ligand with the energy required to stretch the trans ligand from the cobalt(rr1) centre. In the corresponding reduction of Co(NH3),C12 + and cis- and trans-[Co(NH,),-(N&] + the presence of poly-(sodium vinylsulphonate) increases the reaction rate by several orders of magnit~de.'~ The effects of thio-ether donor-atoms as non-bridging ligands in the reduction of cobalt(II1) complexes by iron@) has also been investigated.' The reaction with s-cis-dichloro( 1,8-diamino-3,6-dithiaoctane)-' W. Schmidt J. H. Swinehart and H. Taube J. Amer. Chem. SOC. 1971 93 11 17. J. K. Beattie and F. Basolo Inorg. Chem. 1971 10 486. C. Norris and F. R. Nordmeyer J. Amer. Chem. SOC. 1971,93,4044. R. S. Taylor M. Green and A. G. Sykes J . Chem. SOC. ( A ) 1971,277; M. Green R. S. Taylor and A. G. Sykes ibid. p. 509. K. L. Scott M. Green and A. G. Sykes J. Chem. SOC. ( A ) 1971 3651. 1971,44 1293. l o H. Cohen and D. Meyerstein J. Amer. Chem. SOC. 1971 93 4179. l 3 Y. Kurimura K. Ohashi T. Ohtsuki and K. Yamamoto Bull. Chem. SOC. Japan, l 4 H. Morawetz and G. Gordimer J . Amer. Chem. SOC. 1970,92 7536.l 5 J. H. Worrell and T. A. Jackman J. Amer. Chem. SOC. 1971,93 104 Mechanisms of Inorganic Reactions 495 cobalt(n1) occurs at a rate about lo3 times faster than that for cis-Co(en),Cl + under comparable conditions the effect considered being most marked when the two mutually cis thio-ether sulphur atoms are positioned trans to the bridging atom. Several studies have been made using uranium(II1) as a reductant. In the reactions with cobalt(Ir1) complexes,'6 CO(NH,)~X'+ + U3+ + 5H+ -+ Co2+ + U4+ + 5NH4+ + X-where X- = halide or pseudohalide the relative rates of reaction are strongly indicative of an inner-sphere mechanism where differing X groups stabilize the transition state to varying extents. Halide ions also catalyse the outer-sphere reduction of Co(NH,), + and in complexes with potentially reducible ligands, e.g.Co(NH3),NO2'+ and C O ( N H ~ ) N O ~ ~ + both the ligand and the metal centre undergo reduction. Chloride-ion catalysis of the reduction of Co(NH,),-(H20),,' has also been 0 b s e r ~ e d . l ~ In the reactions with the penta-aquo-chromium(II1) complexes (H20),CrX2 + (X- as above) there is amarked hydrogen-ion dependence of the rate the hydroxide ion being considered to act as an especially favourable bridging ligand in the inner-sphere mechanism. '* Prelimin-ary studies on the thiocyanate catalysis of the reaction between U"' and CrSCN2 + suggest that uranium(II1)-thiocyanate complexes may be more effective reductants than the hydrated ion. Reactions of indium(1) show it to be a fairly strong reductant with a redox potential for the In'/In"' couple similar to the chromium"/Cr"' value.The reduction of iron(m) has been examined in an ethylene atmosphere," the inner-sphere reaction being considered to involve the intermediate formation of indium@) the reaction rate being lo3 less than that for the corresponding chromium(I1) reduction. Iron(u1) has also been used as an oxidant in the reaction with the recently characterized dimeric molybdenum(r1) species Mo,,+(aq),,O the product in the presence of excess iron(II1) being molybdenum(v1). The mechanism of the reversible redox system truns-[Pt(NH,Me),Br,] + 2Fe3 + + 2Br- trans-[Pt(NH2Me),Br4] + 2Fe2+ involves two one-electron steps with the formation of a platinum(I1i) interme-diate,,' which is probably a five-co-ordinate species with one bromide ion attached.In the two-stage oxidation of plutonium(1v) by cerium(Iv),, there is evidence for a plutonium(v) intermediate. The reaction is markedly acidity-dependent strongly inhibited by sulphate ion but independent of nitrate ion. Kinetic studies have been made on the hydrogen dichromate-dichromate equilibrium in perchlorate media2 and the mechanisms of oxidation of a variety l 6 R. T. Wang and J. H. Espenson J . Amer. Chem. SOC. 1971,93 380. " J . D. White and T. W. Newton J . Phys. Chem. 1971,75,2117. '* R. T. Wang and J. H. Espenson J . Amer. Chem. SOC. 1971,93 1629. l 9 R. S. Taylor and A. G. Sykes J . Chem. SOC. ( A ) 1971 1628. 2o A. R. Bowen and H. Taube J . Amer. Chem. SOC. 1971,93,3287. 2 1 A. Peloso and M. Basato J .Chem. SOC. ( A ) 1971 725. 2 2 A. Ekstrom and A. B. McLaren J. Inorg. Nuclear Chem. 1971,33 351 1 . 2 3 J. R. Pladziewicz and J. H. Espenson Inorg. Chem. 1971 10 635 496 A . McAuley of transition-metal complexes by CrV1 have been reviewed.24 Although the nature of the intermediate oxidation states in these systems is still under discussion, Cr" is known to be a reactive species and reactions between Cr" and CrV1 have recently been described.25 In the reduction of CrV1 by hexachloroiridate(m), however,26 the rate data are consistent with the second step in the reduction of the chromium(v1) as the rate-determining process and more than one form of chromium(v) is postulated. There is here no evidence for dinuclear products nor for chloride-ion transfer the products being Cr(Hz0)63+ and IrC162-.The various forms of CrV postulated are considered to differ in co-ordination num-ber since it is known that the change in configuration in chromium(v1) redox reactions occurs at the CrV + Cr" step. In the oxidation of the tantalum cluster ion TasB1-12~' by chromium(v~),~' the first redox step is considered to proceed via two paths involving either hydrogen chromate or dichromate anions. The increase by a factor of about three in the rate for the corresponding chloro-complex is consistent with its stronger reducing properties. Several studies have been made on the iron(Ir)/(m) electron-exchange reaction. The variation in exchange rate measured in either sodium or lithium perchlorate-perchloric acid media is dependent on activity coefficients and on the participa-tion of hydrolysed complex species in the reaction.28 An attempt has been made to investigate the system using Mossbauer spectros~opy,~~ but in the reactant concentrations used (-0.13 M) the exchange between FeOH2+ and Fez+ was too rapid.There is however no evidence for fast exchange of the more highly hydrolysed species. A hydrogen-atom transfer of the Grotthus type is suggested as the mechanism for electron transfer in the mixed water and N-methylacetamide or NN-dimethylacetamide (L) solvent system.30 The reaction rates for the Fe"/Fe"' and Fe"/Fe"'L systems are similar indicating that the solvating role of L is less important than its complexing role. The catalytic effect of thiocyanate on the exchange in DMSO is due to the formation of FeNCS" and Fe(NCS),+ complexes and the thiocyanate group is considered to act as the bridging ligand in the electron tran~fer.~ Internal-reflectance spectroscopy may be used to investigate homogeneous electron-transfer reaction^.^ A variety of systems have been studied including the system T ~ ~ B I - ~ ' -I- Ta6BrlZ4+ 2Ta6Br123t The use of 36Cl- shows that Nb6Cl12'+ is inert to chloride-ion exchange at '' J.H. Espenson Accounts Chem. Res. 1970,3 247. 2 5 G. P. Haight T. J. Huang and B. Z . Shakashiri J . Znorg. Nuclear Chem. 1971 33, 2 6 J. P. Birk and J. W. Gasiewski Znorg. Chem. 1971 10 1587. 2 7 J. H. Espenson and R. J. Kinney Znorg. Chem. 1971 10 376. 2 8 W. J. Gelsema and H. A. Vink Rec. Trav. chim. 1971 90 165. 2 9 M. Komor A. Vertes I.Dezsi and I. Ruff Acta Chim. Acad. Sci. Hung. 1970 66, 285; Chem. Abs. l971,74,68384m; ibid. 1971,75 10861~. 30 G. Wada and R. Yoshihara Kogyo Kagaku Zasshi 1970 73 2309 (Chem. Abs. 1971, 75 10843q). 31 G. Wada N. Yoshizawa and Y. Sakamoto Bull. Chem. SOC. Japan 1971,44 1018. 32 N. Winoerad and T. Kuwana J . Amer. Chem. SOC. 1971,93,4343. 2169 Mechanisms of Inorganic Reactions 497 360 K.33 The ruthenium(]])-catalysed substitution of ruthenium(1n) complexes involves rapid electron transfer between RuX' and Ru3+ (X- = halide) subse-quent to the rate-determining formation of the ruthenium(r1) complex.34 Di-positive gold complexes have been shown to result from the Au'/Au"' electron-exchange reaction in the presence of the ligand cis-1,2-dicyanoethylenedithio-late.35 A tetrahedral Cul*/Cu' redox system has recently been investigated in the reduction of the copper@) dodecatungstocuprate [CuW 12040]6 - to the corre-sponding copper(1) species.36 In the latter complex where there is oxygen-co-ordination to the copper(I) the electron-transfer reaction to the higher oxidation state requires little stereochemical change and no prior dissociation of the multidentate ligand.Metal-ion Ligand Oxidations and Reductions.-The nature of the reactions of metal ions in hip? oxidation states with organic and inorganic substrates con-tinues to be investigated. In many redox reactions the mechanism involves a covalent-bond formation between the oxidant and the reductant and replace-ment as a pre-requisite for redox processes to occur has been discussed.37 From an examination of a large number of reaction types the covalent-bond mediation appears to provide a low-energy pathway for electron transfer.Bonded and non-bonded redox reactions in the oxidation of organic compounds by one-electron oxidants have also been reviewed.38 The '*O-transfer studies in the cobalt(III)-ion oxidation of water have been re~eated,~' the data being consistent with only monomeric ions in acidic media. In the corresponding oxidation of oxalic acid4' there is no direct evidence for complex formation but comparisons of the rate constants for the reactions involving CoOH2+ with those systems where complexes have been detected suggest that intermediate complex formation is in fact the rate-determining process. Complex formation in sulphate media is postulated in the reactions with other dicarboxylate~.~' In this study it is noted that the usual inverse hydrogen-ion dependence of reaction rate holds up to about 3M-H2S04.In more acidic solutions the rate is observed to increase. Similar results have been obtained in -3-8M-HCl0 in the oxidations of hydroxylamine chloride bromide and iodide.42 Under these conditions it is considered that the halides are oxidized via a mechanism involving the rapid reduction of an intermediate COX'' in the presence of excess halide. Complex formation in oxidations involving chromium(v1) have been reported. In the 3 3 J. E. Land H. H. Musgrove and J. E. Teggins J . Less-Common Metals 1971,23,307. 3 4 T. W. Kallen and J. E. Earley Inorg. Chem. 1971 10 1149.35 J. H. Waters T. J. Bergendahl and S. R. Lewis Chem. Comm. 1971 834. 36 D. R. Wexell and M. T. Pope Chem. Comm. 1971,886. 3 7 E. Chaffee and J. 0. Edwards Progr. Inorg. Chem. 1970 13 502. J. S. Littler 'Essays on Free-Radical Chemistry' Chemical Society Special Publica-tions No. 24 Chemical Society London 1970 p. 383. 3 9 R. K. Murmann Inorg. Chem. 1971 10,2070. 4 0 G. Davies and K. 0. Watkins Inorg. Chem. 1970 9 2735. 4 1 J. K. Sthapak and S. Gosh Indian J . Chem. 1971,48,231. 4 2 B. Sramkova J . Zyka and J. Dolezar J . Electroanalyt. Chem. Interfacial Electrochem., 1971 30 169 177 185 498 A . McAuley reaction with nitrous the rate-determining process is the decomposition of the intermediate to yield Cr" and NO3- in a two-electron process. Varying stoicheiometries have been observed in the oxidation of hydr~xylamine~~ depending on the reagent in excess although the reaction order with respect to substrate is always unity.A first-order dependence on oxidant at low concentra-tions is consistent with complex formation. Attempts have been made in a magnetochemical and spectral investigation of the oxidation of mandelic acid to characterize the intermediate oxidation state of the chromium4' and an experi-mental test has been applied to describe the role of Cr" in the reaction with isopropyl Two mechanistic sequences have been applied to describe these reactions and it has been shown that in 97 % acetic acid the rate of disap-pearance of CrV1 and that of the appearance of CrV are identical the initial steps in the mechanism, R2CHOH + HCr0,- + H+ R,CHOCr03H + H 2 0 R2CHOCr0,H '9 R2C=0 + Cr" being followed by rapid reactions involving unstable chromium intermediates and organic radicals.It has been suggested47 that addition of Ce" and Ce"' to reacting solutions of CrV' effectively removes the Cr" formed and so enables the investigation of solely CrV' oxidations. There is evidence for complex formation in the Ce" oxidation of diethylenetriaminepenta-acetic acid48 at [H'] < 1-3M, and intermediates involving both Mn3+ and MnOH2+ have been postulated in the manganese(II1) reaction with methan01.~' The oxidation of phosphorous acid by thallium(n1) in acid perchlorate involves the two-electron oxidation" T1"' + H3PO3 '3 TI' + H3P0 + 2H+ with the formation of a T11''-H3P0 species.The silver(r1) reaction with the same substrate however," takes place via two paths only one of which involves silver ion in the transition state. In the metal-ion-independent step a reactive interme-diate is generated having a lone pair of electrons on the phosphorus as a result of the dissociation of H+ from a P-H bond. Two studies have been presented on the reactions of metal ions with per-chlorate. In the reduction by ruthenium(II) the rate is limited by the slow substitution on the Ru" ion.52 The reaction with titanium(III) however is dependent on the presence of other anion^,'^ the data in sulphate media being 43 D. A. Durham L. Dozsa and M. T. Beck J . Inorg. Nuclear Chem. 1971,33,2971. 44 N. Hlasivcova and J. Novak Coil. Czech. Chem. Comm.1971,36 2027. 4 5 K. H. Heckner K. H. Grupe and R. Landsberg Z . phys. Chem. (Leipzig) 1971, 46 K. B. Wiberg and S. K. Mukherjee J . Amer. Chem. SOC. 1971,93 2545. 4 7 J. Rocek M. P. Doyle and R. J. Swedo J . Amer. Chem. SOC. 1970 92 7599. 48 S. B. Hanna and R. K. Hessley Inorg. Nuclear Chem. Letters 1971 7 83. 49 C. F. Wells and C. Barnes J . Chem. SOC. (A) 1971,430. 5 1 A. Viste D . A. Holm P. L. Wang and G. D. Veith Inorg. Chern. 1971 10 631. 5 2 T. W. Kallen and J. E. Earley Inorg. Chem. 1971 10 1152. '' E. Bishop and N. Evans Tufantu 1970 17 1125. 247 91. K. S. Gupta and Y. K. Gupta J. Chem. Sac. (A) 1971 1180 Mechanisms of Inorganic Reactions 499 more reproducible than those in chloride. Use may be made of the rate measure-ments in this system for the analysis of low concentrations of perchlorate ion.Hexachloroiridate(1v) is quantitatively reduced by tetraphenylborate in a one-electron outer-sphere reaction,54 with BPh radicals formed as intermediates. In the reaction of thiocyanate with pentacyanonitrosylferrate(I1) a blue complex is formed either by irradiation or when the mixture is made basic and re-acidified.55 The mechanism is considered to involve the formation of the species [(NC),Fe(NCS)I4- with oxidation of the nitrosyl to NO,- and a subsequent oxidation of the metal ion to the iron(II1) state. In the hexacyanoferrate(II1)-sulphite reaction,56 spectral changes on rapid mixing are indicative of an interme-diate of the type [(NC),Fe(CNSO3)I4- which is subsequently hydrolysed to [Fe(CN),I4- and SO4,-.Copper(I1) ions have a catalytic effect on this rea~tion.~' The mechanism in this case however is considered to involve a two-electron transfer in the .ternary complex [Cu"-SO -Fe(CN),I3 -. In the reduction of buta-1,3-diene by hexacyanonickelate(~),~* the rate-determining processes follow-ing complex formation involve the reduction of two cyano-nickel intermediates which contain a n-methylallyl and a n-buta- 1,3-diene ligand respectively. The spontaneous reduction of the 1,2,3-triaquodiethylenetriamrninecobalt(111) cation in aqueous perchlorate has been in~estigated,~~ the mechanism involving electron transfer from a co-ordinated nitrogen to the cobalt centre with the formation of a radical which decomposes to yield the methyliminium cation H2C=NH2. In the reaction between molybdovanadate(v) and ascorbic acid or hydrazine,' two electrons participate in the reduction of each mole of inorganic acid and two of the twelve molybdenum atoms are reduced to the + 5 state the central vanadium atom being in that oxidation state.Ammine(pyridine)ruthenium(III) complexes of the type (H,N),RuL3 + (L = pyridine pyrazine or 4-pyridinecarbinol) have been shown to disproportionate in alkaline solution giving the corresponding Ru" complexes,6 the other product being an Ru'" species which is derived from the Ru"' ion by loss of protons from co-ordinated ammonia. Hydroxide ion has been shown to be a reducing agent6, for the mixed ruthenium trimer [(H3N),RuORu(NH3),0Ru(NH,),17 + the initial oxygenated product being an 0' species which reverts to 0,.The mechanism suggested involves the rate-determining attack of hydroxide on the complex to yield a p-peroxo-intermediate. RuIV-hydroxo-complexes have been shown to catalyse the redox reactions of periodate and peroxide with amine~.,~ + 5 4 P. Abley and J. Halpern Chem. Comm. 1971 1238. 5 5 C. Andrade and J. H. Swinehart Inorg. Chim. Acta 1971 5 207. 5 6 J. M. Lancaster and R. S. Murray J . Chem. SOC. ( A ) 1971 2755. 5 i 5 8 D. Bingham and M. G. Burnett J . Chem. SOC. ( A ) 1971 1782. 5 9 P. Wilairat and C. S. Garner J . Inorg. Nuclear Chem. 1971 33 1833. 'O E. F. Tkach and N. A. Polotebnova Zhur. neorg. Khim. 1971 16,210. 6 1 6 2 J . E. Earley and T. Fealey Chem. Comm. 1971 331. '3 V. E. Kalinina R. P. Morozova K. B. Yarsimirskii and 0. N. Ignat'eva Zhur.neorg. M. Solc and J. Veprek-Siska Naturwiss. 1970 57 671. D. P. Rudd and H . Taube Inorg. Chem. 1971,10 1543. Khim. 1971 16 1097 500 A . McAuley In the oxidation of metal complexes of the type FeL32+ (L = bipyridyl or o-phenanthroline) by peroxodipho~phate,~~ there is no evidence for the outer-sphere path exhibited by the isoelectronic S2OS2 - ion the inner-sphere mechan-ism being considered to involve the rate-determining dissociation of the ligand with an approach of P20B4- to the vacant position followed by a fast oxidation step. In the reactions of alkali-metal hexacyanoferrates(rr) with per~ulphate,~ ion pairing has been shown to be important especially where M = K+ Rb', and Cs' the reactant species being MS,08- and Iv~F~(CN),~-. Iodine cations are postulated as intermediates in the oxidation of iodine to iodate by peroxo-disulphate.66 In the corresponding oxidation with isopolymolybdic acids in the presence of GelV or Pv an intermediate heteropolyacid is formed involving the GelV or Pv which reacts in a secondary step with the iodide.67 The formation of iodine bromide68 in sulphuric acid in the reaction I + Br S 2IBr has been shown to involve a concerted termolecular process in which three halogen molecules are involved with Br much less effective than I as a catalyst for the reaction.The oxidation by bromine of [Pt(CN),12- or [Pt(NH3)4]2 + is a two-step reaction6' in which there is first formed a Pt'" aquo-complex with subsequent anation to yield the trans-dibromo-species. The rates of decomposition of bromite7' and hypobromite ions71 have been examined, together with the oxidation of iodate and formate by the latter species.ClO,-, BrO,- and 1 0 - are oxidized to the corresponding perhalates by xenon di-fluoride in aqueous solution.72 Only iodate (at high concentrations) is oxidized directly by the difluoride the other ions reacting with an intermediate produced in the oxidation of water by XeF . Nickel(rr) cobalt(rr) and copper(rr) ions have been shown to catalyse the oxidation of Npv' by hypobromite stable NpV" species being formed whereas Ag' and Fe" have no effect on the rate.73 Similar effects are observed when the oxidant is peroxodi~ulphate,~~ the reaction rate being determined in weakly alkaline media by the rate of dissociation of S,0B2-.Pulse-radiolysis studies of cobalt-cyanide complexes have been carried out, the hydrated electrons produced reacting with the cobalt solutes with high (109-1010 1 mol- s- l) rate constants. In the case of [CO"(CN),]~-,~~ the inter-mediate characterized is the pentacyanocobaltate(1) ion [Co(CN),I4- which on 64 E. Chaffee I . I. Creaser and J. 0. Edwards Inorg. Nuclear Chem. Letters 1971 7 1. 6 5 6 6 F. Secco and S. Celsi J . Chem. Sac. ( A ) 1971 1092. 6 7 I. I. Alekseeva I. I. Nemzer and A. P. Ryser V.U.Z. Khim i khim Tekhnol. 1970 13, R. W. Chlebek and M. W. Lister Canad. J . Chem. 1971,49,2943. 1423 (Chem. Abs. 1971,74 57698r). P. Schweitzer and R. M. Noyes J . Amer. Chem. Soc. 1971,93 3561. W. R. Mason Inorg. Chem. 1971 10 1914. 70 A. Massagli A. Indelli and K.Pergola Inorg. Chim. Acta 1970,4 593. 7 1 M. W. Lister and P. E. McLeod Canad. J . Chem. 1971,49 1987. 72 E. H. Appelman Znorg. Chem. 1971 10 1881. 73 V. P. Shilov N. N . Krot and A. D. Gel'man Radiokhimiya 1970 12 896. 7 4 V. P. Shilov N . N. Krot and A. D. Gel'man Radiokhimiya 1971,13 9. 7 5 G. D. Venerable and J. Halpern J . Amer. Chem. SOC. 1971 93 2176 Mechanisms of Inorganic Reactions 501 reaction with water yields [CO"'(CN),H]~ -. Hydrated electrons react with cobalt(Ir1) complexes of the type [CO(CN),X]~ - the rate constants increasing monotonically' with decreasing ligand-field splitting-parameter A for the heteroligands X = CN H NO2 NCS OH N, C1 and I the mechanism involving an outer-sphere reaction. Tripositive copper ions are formed77 in radiolysed solutions via the reaction Cu" + OH -+ Cu"' and there appears to be acid hydrolysis of this ion (Kh - 9 x moll-').The effects of H202 NO2- Br- and methanol on the rate of disappearance of Cu"' have also been examined. The oxidation and reduction of [Ru(NH3),N2I2+ by y- and electron-pulse-radiolysis have been inve~tigated.~~ Reaction with hydroxyl radicals yields [Ru(NH,)~N~]~ + which rapidly aquates to form [Ru~"(NH,)~OH]~ +. With hydrated electrons however the ruthenium(1) species, [Ru(NH3),N2] + has been characterized as a short-lived intermediate which undergoes dismutation in a bimolecular reaction to yield the original Ru" complex and ruthenium metal. The oxygenation of nicke1(11)-~' and cobalt(II)-'' peptide complexes has been examined reaction proceeding via the formation of a metal-ion-ligand-02 complex and in the case of cobalt the dimeric cobalt(m)-oxygen adduct revert-ing to a hydroperoxo-bridged species.It is of interest however that a stable dimeric cobalt(1r) complex has been reported" in the reaction of molecular oxygen with NN'-bis[4-(5-imidazolylmethyl)-ethylenediamine]cobalt(11). The di-meric rhodium(I1) complexes [L(en),Rh -Rh(en),LI2+ are irreversibly oxidized in oxygen the rates following the order iodo > bromo > chloro for ligands L.82 When oxygen is passed through a solution containing hexammineruthenium(n1) and thiosulphate or thi~phosphate,'~ the product is the N-bonded sulphamato-peniammineruthenium(m) [Ru(NH,),NHSO,] + the reaction being considered to proceed via the transfer of sulphur to the co-ordinated ammonia with subse-quent oxidation by 02.The high pH used in the reaction is consistent with the prior dissociation of a proton from the co-ordinated ammonia so that displace-ment on the sulphur can take place. The reaction with sulphite is considerably slower reflecting the poorer donor properties of this ion. Linear free-energy relationships have been demonstrated between rates of formation and the stability constants of the dioxygen-complexes in the reversible reaction84 trans-[Ir(CO)Cl(R P)2] % [Ir(CO)Cl( 0 2 ) ( R 3 P)2] the rate of oxygen addition being greatly influenced by the group R. " G . D. Venerable Znorg. Chem. 1971,10 1999. '' D. Myerstein Inorg. Chem. 1971 10 639. " J. H. Baxendale and Q. G. Mulazzani J . Znorg.Nuclear Chem. 1971 33 823. 7 9 E. B. Paniago D. C. Weatherburn and D. W. Margerum Chem. Comm. 1971 1427. ' O R. D. Gillard and D. A. Phipps J . Chem. SOC. ( A ) 1971 1074. A. Zuberbuhler T. Kaden and F. Koechlin Helv. Chim. Acta 1971 54 1502. 8 2 R. D. Gillard B. T. Heaton and D. H. Vaughan J . Chem. SOC. ( A ) 1971,736. 8 3 J. N. Armor and H. Taube Znorg. Chem. 1971,10 1570. 84 L. Vaska and L. S. Chen Chem. Comm. 1971 1080 502 2 Substitution Reactions A . McAuley Solvent Exchange and Ligand Exchange.-Studies of water-exchange kinetics in labile aquo- and substituted-aquo- transition-metal ions using 1 7 0 n.m.r. have been reviewed,' particular emphasis being given to cobalt(r1) and nickel@) species. The role of the secondary co-ordination sphere of metal complexes in catalytic reactions has been discussed,86 with a sequence of ligand-exchange reactions envisaged between the inner and outer co-ordination-spheres.Dipolar n.m.r. shifts in paramagnetic complexes may be used to investigate the secondary sphere. A review has also been presented of solvent co-ordination-numbers of metal ions in solution in which mixed solvation of the inner co-ordination sphere is de~cribed.'~ I7O n.m.r. studies on the iron(I1) and nickel(I1) ions in aqueous solution confirm their six-co-ordination.88 Proton n.m.r. spectra are consistent with a co-ordination number of six for Al"' in solution between 233 and 262 Ks9 and for In"' at 173 K,90 although in high halide concentrations there is evidence for InX,- complexes in the latter case.The kinetics of water exchange between aquoammine- and malonato-cobalt(I1) complexes have been reported the labilizing effects of the ligands being compared." The data are suggestive of differing mechanisms for the reactions of cobalt(r1) and nickel(r1) in that four-co-ordinate cobalt may be involved. Ligand replacements in octahedral nickel(I1) complexes have been re~iewed,~' a dissoci-ative-interchange mechanism being favoured for uni- bi- and multi-dentate ligands with prior formation of an outer-sphere complex which yields an inner-sphere species. In the complex triaquo-tribenzo[bfj] [ 1,5,9]triazacyclododecine-nickel(r1) which involves a terdentate Schiff base,93 there is no significant effect of the fused-ring system on the water-exchange rate since no large changes in the bond angles at the nickel centre are involved on formation of the transition state.Evidence for an associative- interchange mechanism in the exchange between Cr(H20)63 + and solvent water is presented from l8O studies at differing pres-s u r e ~ . ~ ~ Exchange of all six water molecules was investigated with log kexch a linear function of pressure. The negative volume of activation is considered to derive mainly from the vacancy created when the incoming water molecule is transferred to the primary co-ordination sphere. Ligand-exchange kinetics of cobalt(r1)- and nickel(1r)-DMSO complexes95 have been examined in mixed solvents (DMSO-CH3N02 and DMSO-CH,Cl,) the independence of exchange parameters on solvent composition being consistent with an SN1 (dissociative) 8 5 J.P. Hunt Co-ordination Chem. Rev, 1971 7 1. 86 8 8 A. M. Chmelnick and D . Fiat J . Amer. Chem. SOC. 1971 93 2875. 89 J. W. Akitt J . Chem. SOC. ( A ) 1971 2865. 90 A. Fratiello D. D. Davis S. Peak and R. E. Schuster Znorg. Chem. 1971 10 1627. 9 1 P. E. Hoggard H. W. Dodgen and J. P. Hunt Inorg. Chem. 1971 10 959. 9 2 R. G. Wilkins Accounts Chem. Res. 1970 3 408. 9 3 J. E. Letter and R. B. Jordan J . Amer. Chem. SOC. 1971,93 864. 9 4 D. R. Stranks and T. W. Swaddle J . Amer. Chem. Soc. 1971,93 2783. 9 5 D. R. Eaton Adv. Chem. Ser. 1971 No. 100 p. 174. S. F. Lincoln Co-ordination Chem. Rev. 1971 6 309. L. S. Frankel Znorg. Chem. 1971 10 814 Mechanisms of Inorganic Reactions 503 mechanism. Studies of the Re04-H,0 exchange using l8O in methanol as solvent show a rate law similar to that which applies in water.96 Laser temperature-jump studies at high pressures9' on some reactions of nickel(1r) and cobalt(I1) with uncharged ligands in water yielded activation volumes AVs - 7-9 cm3 mol- in accord with a dissociative process with slight effects of solvent structure.A similar mechanism is considered to be operative in the formation of the copper(u)-L-dopa complex9' (dopa = 3,4-dihydroxyphenyl-alanine) although the presence of the hydroxy-groups may have a disorientating effect on the ligand's reactivity. In the reactions of substituted copper(I1) ions with bidentate ligands to yield ternary complexes however the rate constants are dependent on the relative positions of replaceable water m01ecules.~~ Inner-sphere effects on the reactions of nickel(I1) with ammonia have been examined in methanol-water mixtures,'00 the maximum rate for Ni(NH3)2+ complex-formation being at - 90 % MeOH.A detailed investigation of solvent effects in the reactions of Ni" and Co" with 2,2'-bipyridyl and 2,2',2"-terpyridyl has been undertaken." The mechanism of complex formation in water does not appear to be generally applicable to other solvents. Rates vary substantially with solvent and divergences of substitution rates from exchange rates have been related to such properties as fluidity and enthalpy of evaporation which are considered to reflect solvent structure. Large effects of solvent structure on the transition state are noted. When the enthalpy of activation is corrected for ligand-field activation-energy however a plot of AH:orr against ASs is linear for all reactions for which data are available in a variety of solvents the effect being discussed in terms of a solvent-modified dissociative process.Transition-metal Complexes.-The principle of hard and soft acids and bases has been related to metal-ion-assisted ligand-substitution processes.'02 A large number of examples are cited indicating that where a soft ligand is being dis-placed by a hard acid the reaction is catalysed by the addition of a (generally labile) soft acid co-ordinated to a harder base the reverse being true for the substitution of a ligand by a soft acid. Symmetry rules for nucleophilic displace-ment reactions have also been described.'03 A review of the reactions of chromium ammine-complexes has been presented.O4 The mechanism of substi-tution ofcomplexes [Cr(H20)5X]2+ (X = Br I or NO3) has been in~estigated,"~ the species of the type shown reacting via an associative interchange mechanism, whereas the corresponding conjugate bases [(H,O),(OH)CrX] + react via a dis-9h R. K. Murmann J. Amer. Chem. Soc. 1971,93,4184. 9 7 E. F. Caldin M. W. Grant and B. B. Hasinoff Chem. Comm. 1971 1351. 9 8 R. L. Karpel K. Kustin A. Kowalak and R. F. Pasternack J. Amer. Chem. SOC., 1971,93 1085. 9 9 M. A. Cobb and D. N . Hague Chem. Comm. 1971 192. l o o W. J . MacKellar and D. B. Rorabacher J. Amer. Chem. Soc. 1971 93,4379. ' O' H. P. Bennett0 and E. F. Caldin J . Chem. Soc. ( A ) 1971 2191 2198 2207 221 1 . lo' M. M. Jones and H .R. Clark J. Inorg. Nuclear Chem. 1971,33,413. l o ' R. G. Pearson Accounts Chem. Res. 1971,4 152. C. S. Garner and D. A. House in 'Transition Metal Chemistry' vol. 6 ed. R. L. Carlin Marcel Dekker Inc. New York 1970. lo' L. Carey W. E. Jones and T. W. Swaddle Inorg. Chem. 1971 10 1566 504 A . McAuIey sociative interchange path. The volume of activation for the aquation of the nitrato-complex is consistent with Cr -0 rather than N-0 bond-cleavage. The hydrolysis of the nitrito-complexes cis- and trans-[Cr(en),(ONO)X] + also in-volves Cr -0 bond-breaking.'06 A linear free-energy relationship has been demonstrated in the reactions of CrOH2+ with X-.'" The rates of aquation of [Cr(H20)sC1]2 + cis- and trans-[Cr(H20),C1,] + and ~is-[(NH~)~Cr(0H,)C11~ + are considerably increased by the presence of HN02 I o 8 the effect being due to nitrito-intermediate formation.The catalysis may however be restricted to complexes containing an aquo ligand in the position cis to the leaving group. Neighbouring-group effects are important in the interconversion of quadri-dentate and quinquedentate edta c~rnplexes,'~~ a high substitution rate being observed on replacement of a water molecule by a carboxylate group. These reactions are believed to have a substantial degree of SN2 character. Another substitution-labile' 'O chromium(II1) complex involves the ligand tetra@-sul-phonatopheny1)porphine where the rates of axial substitution are 103-104 faster than for 'normal' chromium(II1) complexes. In this system the porphyrin ring-system is considered to affect the electronic configuration of the metal centre.Carbon dioxide has been shown to catalyse the formation of edta complexes in the reaction'" (Y4- = edta4-) [(H,N),Cr0Hl2+ + H2YZ- + 4H+ -+ [Cr(Y)H,O]- + 5NH,+ Substitution reactions of octahedral cobalt(u1) complexes have been re-and the mechanisms of base hydrolyses of these species have been disc~ssed."~ Enthalpy data have been used as evidence for a dissociative mechanism in the hydrolysis of complexes of the type [(H3N)SCoX]2+ where X = C1 Br I or N03.'14 The heats of reaction were measured calorimetrically, and on correction for the entropy of activation a constant value was obtained (+ 32 kcal mol- ') for the enthalpy of the transition state. The leaving group X, is considered as essentially dissociated in the activated complex.The kinetics of Ti"'- and Hg"-catalysed aquations of [(H3N),CoC1I2 + and cis- and trans-[Co(en),CI,]+ have been investigated.' 's There is no evidence for complex formation between the cis-complex and Tl"' to yield dinuclear species as there is in the Hg" system. Hg" is also a more efficient catalyst than either T1"' or T10H2+. Aquations of these complexes have also been described in mixed aqueous sol-vents,' l6 in terms of the Grunwald-Winstein treatment the data indicating that for Co"' (and Rh"') species the mechanism involved is S,1 limiting. The rates of l o 6 W. W. Fee J. N. M. Harrowfield and C. S. Garner Inorg. Chem. 1971 10 290. lo' D. Thusius Znorg. Chem. 1971 10 1106. l o * T. C. Matts and P. Moore J .Chem. SOC. ( A ) 1971 1632. l o g R. N. F. Thorneley A. G. Sykes and P. Gans J . Chem. SOC. ( A ) 1971 1494. l l 0 E. B. Fleischer and M. Krishnamurty J . Amer. Chem. SOC. 1971 93 3784. J. E. Earley D. J. Surd L. Crone and D. Quane Chem. Comm. 1970 1401. 1 1 ' C. K. Poon Inorg. Chim. Acta Rev. 1970,4 123. l l J M. L. Tobe Accounts Chem. Res. 1970,3 377. 114 D. A. House and H. K. J. Powell Inorg. Chem. 1971,10 1583. S . W. Foong B. Kipling and A G. Sykes J. Chem. SOC. ( A ) 1971 118. J. Burgessand M. G. Price J . Chem. SOC. ( A ) 1971 3108 Mechanisms of Inorganic Reactions 505 formation and dissociation of complexes between aquo-cobalamin and SCN - , S 0 3 2 - S2032- NCO- N3- I- and Br- have been investigated using fast-reaction devices.' ' Whereas the formation rates vary over about an order of magnitude (1-7 x 102-2.3 x lo3 1 mol-' s-') dissociation rates span a range of lo7 the results being interpreted in terms of a transition state where entering and leaving groups are only loosely bound to the cobalt atom.An electrophilic S,2 reaction is postulated however in the de-alkylation of alkylcobaloxime complexes with rnercury(I1)' ' to yield alkylmercury(I1) species. Electric-field-relaxation methods have been used to study the kinetics of hydrolysis of iron(II1) in aqueous solutions.' ' Relaxation techniques have also been applied to the formation of monochelated complexes of this ion with substi-tuted malonic acids,'20 where the structure of the ligand does not greatly affect the formation rate. Two studies have been made of iron(II1) salicylato-com-plexes,' ' and in the formation of monothenoyltrifluoroacetone species' 22 there is no reaction with the keto-form of the ligand.Rather than the conventional loss of a water molecule from the metal ion it is considered that complex forma-tion is sterically controlled with proton loss from the ligand as an important factor in the rate-determining step. Protonation of the ligand is important in the acid-catalysed aquation of the sulphito-iron(II1) ion. ' A monomer-dimer equilibrium has been characterized in the tetra(psulphopheny1)porphine iron (111) system,' 24 the dimeric complex being 0x0-bridged. The exchange between lanthanide ions (M3') and the [La(edta)] - complex has been studied'25 using radiotracer techniques the rate data being consistent with a mechanism involving the protonation of [La(edta)] - followed by its dissociation with the rapid formation of [M(edta)]-.Complex formation of the NdS0,' cation has been investigated in D20 to evaluate the Eigen mechanism,'26 the reduction in formation rate and the acceleration of the dissociation compared with H 2 0 suggesting that in the lanthanides the cation-solvent exchange may not be the only slow process. The formation of BeSO, however does conform to the two-step me~hanism.'~ Temperature-jump studies on the reactions of molybdate and tungstate with 8-hydroxyquinolines have been carried out,128 the mono-protonated species (M030H)- being the main reactants the reactions of Mod2 - being much slower. In general the rates for D. Thusius J .Amer. Chem. SOC. 1971,93,2629. A. Adin and J. H. Espenson Chem. Comm. 1971 653. P. Hemmes L. D. Rich D. L. Cole and E. M. Eyring J . Phys. Chem. 1971,75 929. 1 2 * F. P. Cavasino and E. Di Dio J . Chem. SOC. ( A ) 1971,3176. 1 2 1 G . Saini and E. Mentasti Znorg. Chim. Acta 1970 4 585; P. G . T. Fogg and R. J. 1 2 2 M. R. Jaffe D . P. Fay M. Cefola and N. Sutin J . Amer. Chem. SOC. 1971,93 2878. 1 2 3 D. W. Carlyle Znorg. Chem. 1971 10 761. 1 2 4 E. B. Fleischer J. M. Palmer T. S. Srivastava and A. Chatterjee J . Amer. Chem. SOC., 1 2 5 W. D'Oliesager and G. R. Choppin J . Znorg. Nuclear Chern. 1971,33 127. 1 2 6 H. B. Silber Chem. Comm. 1971 731. ''' P. Brumm and H. Ruepell Ber. Bunsengesellschaft phys. Chem. 1971 75 102. ''* H. Diebler and R. E. Timms J .Chem. SOC. ( A ) 1971,273. Hall J . Chem. SOC. ( A ) 1971 1365. 1971,93 3162 506 A . McAuley tungstate are an order of magnitude greater than those of molybdate. The effect of 8-quinolinol on the rate of decomposition of polynuclear hydroxy-aluminium cations has also been ~tudied.'~' Substitution reactions of the seven-co-ordinate niobium(v) complex with benzoylphenylhydroxylamine (BPHA) NbO(BPHA), have been de~cribed.'~' BPHA may be replaced by 8-quinolinol and its derivatives and by tropolone the two-term rate law involving one pathway which involves dissociation of the seven-co-ordinated species, whereas in the other pathway complex formation with the entering ligand is postulated. The reactions of mercury(1r)-bovine serum albumin with various ligands have been studied using stopped-flow 35Cl n.m.r.13 The mechanism of displacement of thioethers co-ordinated to platinum(I1) complexes has been in~estigated,'~~ the rate of reaction being dependent on the degree of bond-making between the nucleophile and the metal centre.Some stereoelectric hindrance is considered to derive from the interference between the non-bonded electron pairs on the sulphur atom and the charge distribution on the complex. The kinetics of the ring opening in complexes Pd(PhSCH2CH2-SPh)X (X = Cl Br SCN or N3) by amines have been followed in 1,2-dimethoxy-ethane. 1 3 3 The trans-effect sequence is observed and the anomalous cis-effect order of anionic ligands which was observed previously in systems containing sulphides and attributed to stereoelectric hindrance almost disappears in the present ligand system.The cleavage of halogen-bridged dinuclear complexes of Pt" by olefins has been studied.' 34 With mono-olefins the reaction products are of the type [Pt(olefin)Br,] - whereas with 1,5-cyclo-octadiene unsymmetrical cleav-age is observed. With amines however diamine-bridged species are obtained. The influence of steric and electronic effects of ligands on the activity and specificity of transition-metal catalysts has been de~cribed,'~ and the metal-ion control of chemical reactions has been d i s c ~ s s e d . ' ~ ~ The metal ion may alter the character of the medium by change in ionic strength or in prior association with the substrate may yield an intermediate which subsequently undergoes reaction.Homogeneous catalytic processes are considered to be multi-step rather than single chemical reactions. The mechanisms of incorporation of metal ions into porphyrin systems have been reviewed together with substitution and electron-transfer proce~ses.'~~ In the reaction of Zn" and Cd" with such systems,13* it is considered that the differences in the rate of introduction of the metal-ion into the ring system in porphyrins and N-methylporphyrins may be due to a transition state where there is non-planarity of the porphyrin as well as to statistical and basicity effects. The metal-ion catalysis of ethyl oxalate ' 2 9 I 3 O R. C. Johnson and A. Syamal J . Inorg. Nuclear Chem. 1971,33,2547. 1 3 ' 1 3 2 L. Cattalini G. Marangoni S. Degetto and M. Brunelli Inorg.Chem. 1971 10 1545. 1 3 3 L. Cattalini G. Marangoni J. S. Coe M. Vidaei and M. Martelli J . Chem. Soc. ( A ) , ' 34 M. M. Muir and E. M. Cancio fnorg. Chim. Acta 1971,4 565 568. 1 3 5 G . Henrici-Olive and S . Olive Angew. Chem. Internat Edn. 1971 10 105. 1 3 6 1 3 ' 1 3 * B. Shah B. Shears and P. Hambright fnorg. Chem. 1971 10 1829. R. C. Turner and W. Sulaiman Canad. J . Chem. 1971,49 1683. J. L. Sudmeier and J. J . Pesek fnorg. Chem. 1971 10 860. 1971 593. D. H. Busch Science 1971 171 241. P. Hambright Co-ordination Chem. Reti. 1971 6 247 Mechanisms of Inorganic Reactions 507 hydrolysis has been examined,'39 the rates decreasing in the order Cu" > Pb" > Zn" > Ni" > Co" > Mg" the data being interpreted in terms of complex formation followed by slow attack of the hydroxide ion.The base hydrolysis of L-( +)-histidine methyl ester is also metal-ion (Cu" Ni") cataly~ed.'~' The rate of decarboxylation of 3-oxoglutaric acid is greatly accelerated in the presence of Cu" Ni" and especially Mn" and has been suggested as a model system for an enzymic rea~tion.'~' It is of interest that n-bonding of the manga-nese(I1) to 2,2'-bipyridyl increases the catalytic activity by a factor of ten whereas the effect is less marked (twofold) for the other metal ions. Non-metal Systems.-Kinetic studies have been made on the acid-catalysed hydrolysis of nitrilotriphenoxysilanes (ntpSiX) which contain a five-co-ordinate silicon atom. 142 Although the same reaction product (nitrilotriphenol) is observed in all cases the mechanism is dependent on substituent X.When X = Me Ph or p-tolyl the rate-determining process involves the rupture of a protonated Si-0 bond. When X = C1 however an ion-pair intermediate is postulated (ntpSif . . . C1-) which is considered to be stabilized by (p-d) n-bond-ing in the siliconium ion. Kinetic evidence has been presented for a six-co-ordinate silicon intermediate in the racemization of chloroethyl-cc-naphthyl-phenyl~ilane'~~ where two solvent molecules are co-ordinated in a symmetrical octahedral species. Although bimolecular substitutions at two-co-ordinate sulphur have been considered to be synchronous &2 processes an investigation of substitution reactions of 2,4-dichloroaniline with various arylsulphenani-l i d e ~ ' ~ ~ shows substantial substituent electronic effects requiring modification of this view.An interpretation may be that the ground state is stabilized relative to the transition state by interaction between the nitrogen and the sulphur. The exchange of a t-butyl group by an ethyl in the reaction : (Bu'O)~P + EtI Bu'I + (Bu'O),P(OEt) has been studied 14' conductometrically in acetonitrile. Investigations have been made into nucleophilic substitution at tetrahedral boron.'46 Trialkylamine-boranes (alkyl = Et or Me) react with tri-n-butylphosphine to yield tri-n-butylphosphine-borane and the corresponding amine. Reactions are overall second-order and an S,2-B mechanism is proposed with slow nucleophilic attack of the phosphine at the boron centre. Similar results are observed with B-alkyl-and B-aryl-substituted trimethylamine-boranes with the exception of trimethyl-amine-t-butylborane where a predominantly first order SN1 -B reaction occurs. The same mechanism involving a first-order dissociation is observed with methylamine-diarylborane substrates. 1 3 ' ) G. L. Johnson and R. J . Angelici J. Amer. Chem. Soc. 1971,93 1106. 14' 1 4 2 1 4 3 1 4 4 F. A. Davis S. Divald and A. H. Confer Chem. Camm. 1971 294. 1 4 5 J . M. Cachaza M. A. Herraez and A. Varela Anales de Quim. 1970 66 993. 1 4 6 W. L. Budde and M. F. Hawthorne J. Amer. Chem. SOC. 1971 93 3147; D. E. Walmsley W. L. Budde and M. F. Hawthorne ibid. p. 3150; F. J. Lalor T. Paxson, and M. F. Hawthorne ibid. p. 3156. R. W. Hay and P. J. Morris J . Chem. SOC. ( A ) 1971 1524. R. W. Hay and K. N. Leong J. Chem. Sac. ( A ) 1971 3639. R. E. Timms J. Chem. Soc. ( A ) 1971 1969. R. J. P. Corriu and M. Leard Chem. Comm. 1971 1086

ISSN:0069-3022    

DOI:10.1039/GR9716800493

出版商:RSC    

年代:1971

数据来源: RSC

摘要:

508 ERRATA Volume 67A 1WO Page 401 second paragraph line 2: Page 444 third line from foot of main text : for “aqueous bipyridyl” read “ethanolic bipyridyl”. for “Ph,PPt(CO) (SnC1,)Cl” read “(Ph,P),Pt(CO) (SnCI,),”

ISSN:0069-3022    

DOI:10.1039/GR9716800508

出版商:RSC    

年代:1971

数据来源: RSC

摘要:

AUTHOR INDEX Abel E. W. 277 420 463, Aberg M. 372. Abley P. 275 392 499. Ablordeppey V. K. 34. Abraham M. H. 102 104, Abrahams S. C. 306 360. Abrahamson E. W. 154, 156 164. Absar I. 318. Abu Shady A. I. 233. Ackerman R. A. 165. Ackermann T. A. 91 103. Ackermann M. N. 407. Ackley S. 338. Acuna A. U. 137. Adair T. W. 33 34. Adams C. J. 334 353. Adams D. B. 182 420, 459. Adams D. M. 47 52 53, 57 58 59. Adams G. P. 309. Adams R. 106. Adams R. M. 261 284. Adams W. A. 338. Adams W. J. 359. Adamson G. W. 476. Addison C. C. 252 253, 254 41 1. Adin A. 505. Adler D. 241. Adler E. L. 44. Adler S. E. 354. Adlfinger K. H. 339. Adzamli K. 462. Agnes G. 445. Agrawal M. C. 388. Aguiar A. M. 488. Ahlberg P. 102. Ahmed I. Y. 292.Ahrens M. L. 103. Aiello R. 200. Aigueperse J. 236. Ainscough E. W. 446, Aires B. E. 396. Airey W. 306. Aiyar L. 108. Aizawa M. 339. Akerlof G. 98. Akimova G. S. 312. Akins D. L. 155. 481. 105. 448 489. Akitt J. W. 89 288 502. Aksartov M. M. 272. Alais P. 44. Albano V. G. 422. Albinati A. 466. Aleksandrov G. G. 442, Aleksandrov Yu. A. 311, Aleksanyan V. T. 467. Alekseeva I. I. 500. Alexander L. E. 334 353, Alexander M. N. 284. Alford K. J. 276. Ali S. I. 306. Alich A, 420. Aliev S. S. 32 37 42. Allan D. E. 212. Allcock H. R. 328. Allegra G. 267 442. Allegra J. 34. Allen E. A. 413. Allen F. H. 313. Allen G. C. 11 406. Allen J. F. 387. Allen L. C. 10,21 22 336, Allenstein E. 296. Allred A. L 302 31 1. Almenningen.A. 285,286. Al-Obaidi K. H. 484. Alper H. 423. Alpert S. S. 44. Al-Sader B. H. 185. Altenburg H. 329. Altham J. A. 235. Altmann S. L. 56. Al’tshuler 0. V. 217. Alyea E. C. 406. Amberger E. 259. Ambs W. J. 205. Amenomiya Y. 248. Amin K. 110. Amme R. C. 29. Amphlett J. C. 177. Anand S. K. 478. Anand S. P. 469. Anatskaya N. I. 367. Andal R. K. 488. Andets U. 425. Anderson A. S. 472. Anderson B. 44. Anderson D. G. 301. 470. 316 333. 405. 338 339. Anderson G. A. 283 286. Anderson J. E. 48. Anderson J. S. 314. Anderson J. W. 285 299, Anderson L. R. 277 297. Anderson P. W. 15. Anderson R. 129. Anderson R. H. 331. Anderson R. L. 440. Anderson S. N. 444. Anderson W. A. 399. Anderson S. 333. Andrade C.499. Andre J. M. 17 18 19. Andreeta A. 435. Andreev E. A. 154. Andrew J. E. 77. Andrews L. 340 359. Andrews L. J. 154 164, Andrews S. B. 301. Andrianov K. A. 305. Andrist A. H. 188. Ang H. G. 331. Angelici R. J. 485 489, Angell C. L. 208. Angelone L. 309. Anisimov M. A. 35. Anker M. W. 431. Anorova G. A. 272. Anselmi C. 325. Anson F. C. 479. Anthony R. G. 316. Anton A. 88. Antoshin G. V. 247. Aoki T. 3 1. Appel R. 323 349. Appelman E. H. 251 339, 360,363 500. Aquino D. C. 395. Arai Y . 203. Arakawa K. 33 337. Arbus A. 257. Archer M. K. 368. Archer R. D. 380. Archie W. C. 187. Archila A. 115. Ardoin N. 301. Arefiev I. M. 35. Aresta M. 448 478 483. Arey W. F. jun. 195,207. Arghiropoulas B. 236. 300 312. 166.507 5 10 Author Index Armitage I. 368. Armor J. N. 389,415 501. Armstrong D. R. 278. Armstrong G. T. 359. Arnett E. M. 255. Arnold R. T. 44. Aron B. M. 351. Arora C. L. 342 343 350. Arpe H. J. 353. Arrington D. E. 350. Arshadi M. 86 88. Aruldhas G. 356. Ase K. 351. Ashby E. C. 256,257,277, 283 285. Ashcroft B. W. C. 279. Ashcroft S. J. 467. Ashe A. J. 259 320. Ashton D. S . 181. h t r o m A. 333. Atkins T. J. 456 457. Atkinson G. 35 38 89. Atkinson J. G. 447. Atkinson L. K. 381. Atkinson R. 191. Atovmyan L. O. 308 381. Atwood J. L. 256 286. Aubke F. 313 346 358, Audette R. J. 387. Audrieth L. F. 343. Auger Y . 345 346. Aumann R. 464. Austin W. K. jun. 298. Avitabile G. 282 398. Avramenko V. N. 38. Awasthi 0.N. 34. Awasthi S. K. 372. Aymad H. 209. Azada T. 132. Aziz R. A. 30. 361. Babaeva V. P. 330. Babb B. E. 275. Babb D. P. 317. Babyak A. G. 323. Back R. A. 182. Bacon J. 11 333. Badcock C. C. 168. Baddley W. H. 462. Bader F. 38. Bader R. F. W. 22 24. Badiali D. J. P. 86. Badley E. M. 438 440. Baechler R. D. 321. Baenziger N. C. 408. Baer M. 192. Baer T. 190. Barnighausen H. 296. Bagg J. W. 177. Bagus P. S. 22. Baiamonte V. D. 141 336. Bailey F. P. 116. Bailey J. 37. Bailey N. A. 452. Bair E. J. 141. Baird M. C. 399 458,462. Baird R. M. 300. Baisley V. C. 164. Bajpai K. K. 294. Bakeeva S. S. 351. Baker K. A. 24. Baker R. J. 398. Baker R. R. 184. Baker R. T. K. 191. Baker W. A. jun. 79. Balahura R. J. 493.Balakrishnan P. V. 469. Balch A. L. 438. Baldwin D. A. 373. Baldwin J. E. 187 188. Baldwin R. R. 184. Balfour W. J. 138 256. Balitactac H. 42. Ball J. J. 335. Ball P. W. 61. Ballard D. H. 444. Ballhausen C. J. 71. Ballmark P. 155 156. Bgloiu L. M. 401. Bambushek I. Y. 323. Ban K. 310. Bancroft G. M. 386. Band S. J. 178 181. Bandoli G. 313 372. Bandurco V. T. 407. Banerjee S. 65. Banister A. J. 342. Bannister M. J. 372. Bannister W. D. 450. Barabanova A. S. 353. Baram V. 252. Baranski A. 239. Barat F. 360. Barbarella G. 117. Barbe A, 343. Barbeau C. 429. Barber M. 330 420 473. Barbieri R. 31 1. Barefield E. K. 61. Barile C. A. 152. Barinov I. V. 447. Barker C . 358. Barker G. K. 307. Barker J. R. 125. Barker S.L. 379. Barlex D. M. 454. Barlow A. J. 41 43. Barlow G. A. 96. Barmby D. S. 216. Ramard. P. F. B 55. Barnes C. 498. Barnes J. A. 74 75 77. Barnes J. C. 368. Barnes P. 339. Barnes P. A. 400. Barnes R. G. 284. Barnes W. C. 74. Barnett W. J. 110. Baronnet F. 185. Barr J. 350. Barraclough C. G. 73 80. Barrau J. 308. Barrer R. M. 196 198, Barrett J. 315. Barrett P. B. 374. Barrick J. C. 341, Barrie J. A. 338. Barrow M. J. 473 477. Barrow R. F. 354. Bart J. C. J. 476. Bartell L. S. 359 363. Barth C. A. 137. Barthel J. 86. Barthomeuf D. 206. Bartlett P. D. 186. Bartlett R. J. 15. Barton A. F. M. 356. Barton C. J. 280. Barton L. 273. Barton S. C. 190. Barua A. K. 30. Basato M. 495. Basch H. 21 183 362. Basco N.138 155 156, 168 171 173 177 359. Bascom W. D. 338. Basi J. S. 406. Basnich B. 404. Basolo F. 392 397 488, Bass A. M. 134 149 155, Bass H. E. 28. Bassett P. J. 278 298. Bassi I. W. 442. Bassindale A. R. 302. Bates D. R. 135. Bathelt W. 431. Batsanov S. S. 315. Batty C. J 366. Raudler. M . . 318 3.30. 452. Bauer H. J. 28 38. Bauer S. H. 190 262. Bauer W. 188. Baughman R. H. 272. Baukov Y. I. 305. Baulch D. L. 124. Bauld T. J. 40. Baumann R. 335. 200. 494. 168 183 Author Zndes 51 1 Baumgartner E. K. 35. Baxendale J . H . 501. Baybarz R. D. 370. Bayliss W. E. 132. Bayreuther H. 296. Bazulin P. 38. Beach R. G. 256,285. Beachley 0. T. 283. Beagley B. 298 325. Beak P. 116. Beale J. P. 397. Beall H. 266. Beam R .J. 331. Bear C. A. 400. Bear I. J. 375. Beattie I. R. 50 52 351, Beattie J. K. 397 403, Beauchamp J . L. 318. Beaud. P. 119. Beaudet R. A. 268 269, Beaumont A. G. 415. Beaumont R. 206. Beck G. R. 425. Beck H . - J . 440. Beck M . T. 498. Beck W. 295 414 422, 437 452 455 485 487. Becke-Goehring M. 362, 328 331. Becker G. 43 1. Becker K. H. 137 141. Becker W. 414. Beckham T. M. 445. Beckley R. S. 455. Beddall P. M. 24. Beddoe P. G. 404. Bednarski M. 293. Beecher R. 212. Beenakker J. J. M. 30. Beer D. C. 271. Begland R. W. 296. Begum A. 299 319 330. Behar D. 340. Behnen S. W. 29. Behrens H. 491. Behret H. 86. Beitelschmidt W. 319. Belford R. L. 73. Belik P. I. 272. Bell A. P. 450 489. Bell J. A. 183.Bell J. T. 337. Bell J. W. 56. Bell R. P. 104 11 1 112, 113 120. Bell S. A. 402. Bell T. N. 181. Bellama J. M. 279 307, 353. 404 494. 340. 310. Bellamy L. J. 337. Bellisio J . A. 129. Bellitto C. 383. Bellon P. L. 400 488. Belluco U. 419. Bellut H. 281. Belousova E. M. 309. Belov N. V. 306. Belov V. Z. 365. Belyi A. A. 483. Benda H. 305. Bendazzoli G. L. 340. Bender C. F. 183. Bender M. L. 101. Bendle S. 445. Benedetti E. 267. Benedict J. J. 438. Benesovsky F. 284. Benkeser R. A. 299. Ben-Naim A. 337. Bennett J. M. 198 199. Bennett L. E. 493. Bennett M. A. 443 444, Bennett M. J. 410 488. Bennett R. L. 490. Bennetto H. P. 106 503. Ben-Shoshan R. 468. Benson S. W. 175 176, 177 182 186 189 190. Ben Taarit Y.206 215, 218. Bentham J. E. 299,482. Bentley F. F. 57 331. Bentley R. B. 69. Bentrude W. G. 322. Berberian J. G. 41. Bercaw. J . E 43.5. 469. Berces T. 185. Berdyer A. A, 44. Beres J. 261. Bergendahl T. J. 292 401, Bergerud J. R. 302. Bergman N. A. 112. Berka L. H. 409. Berkley R. 18 1 . Berkowitz J. 354 355, Berlin A. A. 252 410. Berliner E. M. 309. Bernal I. 383. Bernasconi C. F. 120. Berndt M. 300. Berniaz A. F. 292. Bernstein H. J. 357. Bernstein J . L. 306 360. Bernstein M. D. 265. Bernstein P. A. 297. Bernstein R. B. 354. Berry M. J. 173. Berry R. S. 355. 449 462 497. 361 362. Berson J . A. 188. Bertie J. E. 56. Bertin F. 256. Bertini I. 41 1 . Bertrand J. A. 76 390, Bertrand R. D. 322. Beste K.W. 28. Beveridge D. L. 10. Bew M. J. 73. Beyer K. D. 155. Beyer R. T. 27. Beyl V. 296. Bezman S. A. 460 480. Bhagavantam S. 56. Bhatia A. B. 44. Bhatnagar V. M. 316. Bhattacharyya S. K. 243. Bhuiyan A. L. 287. Biallas M. J. 279. Bickel A. F. 109. Bickelhaupt F. 281. Bickley R. I. 228. Biczo G. 17. Biddlestone M. 328. Bied-Charreton C. 445. Biedenkapp D. 141. Biedermann G . 97. Biederrnann J . M. 286. Bielariski A. 228 229. Bieller U. 326 328. Bierenbaum H. S. 204. Bigorgne M. 452 474. Bigotto A. 419. Bilevich A. V. 31. Billingsley F. P. 13. Billingsley J. 155. Billo E. J. 120. Bilofsky H. S. 266. Binder C. F. 22. Binder H. 326 327. Bingham D. 499. Biran C. 301. Birchall T. 270 307 315. Bird B. D. 404. Bird R.B. 154. Bird S. R. A. 315 481. Birk J . P. 496. Birnbot R. 366. Biryukov B. P. 490. Bishop E. 498. Bishop E. O. 276. Bishop J. J. 437. Bishop W. P. 126. Bissert G. 258. Bister K. 257. Bjorklund C. 483. Black G. 136 140 142, Blackborow J. R. 283. Blackmore J. E. 283. Blackmore T. 454. 394. 155 5 12 Blades A. T. 190. Blair E. J. 336. Blair L. K. 104. Blais N. C. 355. Blake A. B. 77. Blake D. M. 452 488. Blanchard J. 357. Blanchard M. 247. Blanco S. G. 278. Blandamer M. J. 35 39, Blaser B. 323. Blaschette A. 344 349. Bleaney B. 7 1. Bleekrode R. 133. Bleidelis Y. Y. 308. Blend H. 31. Bless P. W. 309. Blick K. E. 344. Blizzard A. C. 11. Bloch R. 339. Blomquist R. 33. Bloom H. 316. Bloom M. B. D. 383. Bloor J.E. 11 13. Bloxsidge J. 121. Blumstein C. 187. Blundell T. L. 490. Boak D. S. 181. Boal D. 351 363. Board R. D. 338. Bochkareva V. A. 382. Bock B. 252 41 1. Bock H. 276 282 319. Bockris J. O. 8 1. Boden J. C. 155 182. Bodner B. M. 265 266, Boeck A. 294. Bohme H. 319. Boenig I. A. 283. Bonnemann H. 465. Boer F. P. 310 314 396. Boersma M. A. M. 188. Bottinger P. 300. Bowing W. G. 325. Boeyens J. C. A. 368. Bogdanov V. S. 277. Boggs J. E. 322. Bogomolov V. I. 209,212. BohaCkova V. 81. Bohl R. D. 267. Bohlander R. A. 337. Bohme D. K. 104. Bohn G. T. 273. Bohn M. D. 272. Bohn R. K. 272. Bokii N. G. 314 470. Boldyreva 0. G. 281. Boleslawski M. 287. Bolton A. P.,208,210,217. Bombieri G. 398 448. 337. 271. BonaCiC V.25. Bonamico M. 74 376, Bonati F. 479. Bond A. 282,454. Bond A. M. 94,414. Bond G. C. 195. Bonds W. D. jun. 380. Bondybey V. 358. Bonnelle J. P. 240. Bonner 0. D. 337. Bonnett R. 407. Bonnette A. K. jun. 387. Boon J. P. 33. Boone L. 42. Boon-Hian Loo. 356. Boorman P. M. 380. Booth B. L. 437,450,453. Booth J. 452. Bor G. 420 424. Borch R. F. 265. Bordwell F. G. 106 113. Boreskov G. K. 247. Borgoyakov V. A. 352. Bories M. T. 290. Borisenko A. A. 31 8. Borisova V. P. 353. Bornatsch W. 257. Bornmann J. A. 280. Borodina N. N. 371. Boronina N. N. 446. Borodko Yu. G. 408,483. Bos A. 314. Boschetto D. J. 458. Boschi T. 462 466. Bose K. S. 394. Bose R. 43. Bosman A. J. 241. Bossa M. 11. Bosselaar R. 378. Bothner-by A.A. 322. Bott J. F. 29 345. Bottomley F. 389 408, Boucher L. J. 383. Bouchoux A. M. 166. Boudart M. 229. Boudreaux E. A. 72. Bougon R. 358 359 360. Bowden K. 108 109. Bowen A. R. 381,495. Bowen D. E. 34. Bowen J. R. 154. Bowen L. H. 333. Bowen R. E. 92. Bowers D. M. 408. Bowers K. D. 71. Bowker K. W. 106. Bowler D. 290. Bowles A. J. 181. Bowrey M. 184. Bowser R. J. 244. 414. 484. Author Index Boyce C. B. C. 329. Boyd D. 357. Boylan M. J. 78 42 1. Boyle E. A. 104. Boyle W. J. jun. 106 1 13. Bozak R. E. 469. Bozon-Verduraz F. 236. Brabetz H. 459 485. Brackett G. C. 385. Brackman R. T. 127. Bradford C. W. 426. Bradley D. C. 406 407. Bradley E. B. 344. Bradley J. N. 184. Bradley R. H. 359. Bradspies J.I. 339. Brainina E. M. 470. Braitsch D. M. 477. Braterman P. S. 420 421, 423 430 457 490 491. Brauman J. I. 104 186, 187. Braun L. M. 261. Braun R. 303. Braun R. A, 261 284. Braun W. 126 127 134, 140 149 155 168 183, 342. Braunagel B. 300. Bray L. S. 425. Breazale M. A. 44. Breck D. W. 196 200. Breckenridge W. H. 133, Breen J. J. 322. Bregadze V. I. 272. Brehm B. 362. Brehm H. P. 423. Breit G. 127. Breitinger D. 319. Breitmaier E. 487. Breitschwerdt K. G. 85. Brener L. 455. Bressan M. 414 437. Bressel B. 344. Brett C. L. 119. Breuer S. W. 262. Brewer L. 98 152. Brice M. D. 426. Bridges D. M. 430. Bridoux M. 50. Brier P. N. 359. Briggs A. G. 155 156. Briggs D. 459. Briggs G. 351. Briggs P. R. 298. Bright A.435 446. Bright D. 461 463. Bright W. M. 346. Brignole A. 385. Brill R. 265. Brill T. B. 473. 145 Author Index 513 Brinzinger H. H. 469,470. Brisseau L. 256. Britt C. O. 322. Brittain A. H. 317. Brittain E. F. H. 282. Broadbent T. 168. Broadhead J. 39. Brocklehurst B. 136. Brodhead D. C. 129. Brodie A. M. 489. Broida H. P. 156. Broitman M. O. 408 483. Brokaw M. L. 109. Brokenshire J. L. 182. Bromilow R. H. 107. Brook A. G. 301. Brookhart M. 478. Brooks C. T. 186. Brooks E. H. 480. Brooks E. J. 338. Broom A. 104. Brown A. 186. Brown C. K. 451,465. Brown D. 370 371. Brown D. A. 420. Brown D. B. 388. Brown D. C. 284. Brown D. H. 323. Brown E. 191. Brown H. C. 261 273, 274 277 299. Brown J. 359. Brown J.M. 187 465. Brown L. M. 289. Brown R. D. 7 9 10 11. Brown T. L. 254,430,444, Browning J. 477. Brownlee G. S. 313. Brubaker G. R. 395. Bruce M. I. 282,428,444, 446 454 489,490. Brunvoli J. 58. Bruser W. 442. Bruice T. C. 107. Brumm P. 505. Brummer S. B. 339. Brundle C. R. 361 362. Brune F. 442. Brune H. A. 468. Brunel L. C. 357. Brunelli M. 506. Brunner H. 419,487. Brunton G. 375. Brunvoll J. 477. Brus L. E. 128 356. Bryan P. S. 276 320. Bryan R. F. 314,422. Bryant J. T. 176. Buback M. 357. Bubnov Yu. N. 275. Bucaro J. A. 86. 461. Buchholz R. F. 110. Buchkremer J. 467. Buchler J. W. 415. Buchwald H. E. 120. Budde W. L. 261 507. Budenz R. 340 344. Budesinsky B. W. 352. Budnik R. A. 478. Bultjer U. 304.Buenker R. J. 22. Biinzli J. C. 377. Burger H. 290 349 406, Bufe U. A. 371. Buglass A. J. 110. Buist G. J. 120. Bukalov S. S. 467. Buketov E. A. 351. Bulkowski J. E. 307. Bull H. 11 5. Bull W. E. 402. Bullen G. J. 277 326. Bullock G. E. 155 180. Bullock R. J. 369. Bulmer R. S. 121. Bulten E. J. 308. Bulychev B. M. 285. Buncel E. 108. Bundy F. P. 396. Bunel S. 41 1. Bunker D. L. 192 193. Bunker P. R. 56 357. Bunnell C. A. 451. Bunton C. A. 120. Burbank R. D. 362. Burbidge B. W. 204. Burcat A. 181 190. Burczyk K. 349. Burden F. R. 7 10. Burdett J. K. 393 421, Burg A. B. 263 321. Burger K. 455. Burgess J. 106 380 504. Burke A. R. 271. Burlamacchi L. 382. Burlitch J. M. 287 473. Burmeister J. L. 379 412, Burnelle L.22. Burnett J. L. 370. Burnett M. G. 94 436, Burnett R. E. 488. Burns G. 150 359. Burns J. H. 370. Bursian N. R. 204. Burton P. G. 11. Burton R. E. 90. Burundukov K. M. 37, Busch D. H. 61 506. 481. 483. 449. 499. 44. Busetto L. 485. Bushweller C. H. 266. Buslaev Yu. A. 315 377, Butin K. P. 272. Butler K. D. 78. Butler K. R. 378. Butler M. M. 113 114. Butter E. 368. Buzina N. A. 424 436. Byberg J. 93. Byrd J. E. 452,455. 382 405. Cabana A. 91. Cachaza J. M. 507. Cachet H. 86. Cade P. E. 24. Cadioli B. 340. Cadman P. 149 180 182. Cady G. H. 345. Caglioti L. 448. Caich S. 156. Cairncross A. 296 459. Cairns E. J. 258. Cala F. R. 177. Calabrese J. C. 263. Calais J.-L. 20. Calas R. 300 301. Calderazzo F.374. Calderon J. L. 470 472, Caldin E. F. 106 114 119, Caldow G. L. 457. Callahan K. P. 270. Callear A. B. 29 124 130, 131 132 133 135 138, 144 147 155 160 161, 168 171 177. Calligaris M. 444. Calvert J. G. 130 168, Calvin M. 257. Calvo C. 341. Cameron A. F. 325 401. Cameron R. 109. Cameron T. S. 321 322, Camia M. 425. Campbell I. M. 136. Campbell J. M. 132. Campbell M. M. 188. Camus A. 479. Cancio E. M. 506. Candau S. J. 43. Candela G. A. 474. Cannas M. 412. Cannemeijer F. 3 1. Canterford J. H. 384. 484. 121 503. 245. 326 491 5 14 Author Index Canziani F. 447 469. Capestan M. 257. Carbonaro A. 467. Cardaci G. 429. Cardin A. D. 263. Cardin D. J. 441. Carey C. 28. Carey L. 503. Carey P. R. 276. Cariati F.400 479 488. Carless H. A. J. 189. Carlisle G. O. 75. Carloe C. 127. Carlson G. A. 173. Carlyle D. W. 505. Carnevale E. H. 28. Carney G. P. 28. Carpenter D. A. 390. Carr R. W. 183. Carrera S. M. 278. Carrington A. 69. Carrington T. 127 140. Carroll H. F. 191. Carruthers J. D. 249. Carta G. 412. Carter H. A. 346 358. Carter J. C. 265. Carter V. B. 396. Carturan G. 343. Carty A. J. 399. Carunchio V. 315. Casas F. 177. Case B. 83. Case D. A. 289. Casey A. T. 77. Casey C. P. 440 451 459. Casey E. J. 336. Casey M. 482 490. Cashman D. 471. Casilio L. M. 111. Casper J. M. 331. Cassar L. 429 455. Castleman A. W. jun., Cataliotti R. 429. Cattalini L. 397 448 506. Catterall R. 254. Cattrall R. W. 76. Caughey W.S . 385. Caughlan C. N. 369. Caulton K. G. 392. Cavasino F. P. 505. Cavaleiro J. A. S. 294. Cavell R. G. 168 323,324. Cayley G. R. 120. Ceasar G. P. 54. Cefalu R. 31 1. Cefola M. 120 505. Celsi S. 344 500. Cenini S. 452 486 489. Centofanti L. F. 330. Cerf R. 38. 338. Cernik M. 351. Cesari M. 477. Cetini G. 426. Cetinkaya B. 276 407, Chadha S. L. 344. Chaffee E. 497 500. Chaikin A. M. 356. Chaivanov B. B. 362. Chakravarty N. C. 65. Chamberlain A. T. 55. Chamberlain G. A. 177, Chambers R. D. 11. Chambers W. J. 420. Chan A. S. K. 423. Chan L. Y. Y. 432,483. Chan S . C. 176. Chandra S. C. 31 1. Chang B. C. 329. Chang C. J. 109. Chang T. Y. 183. Chao J. 336. Charcossett H. 395. Charley L. M. 485. Charlton T. L.323. Charpin P. 359. Charters P. E. 336. Chasanov M. G. 33. Chase C. E. 33. Chasteen N. D. 73. Chatalie A. 156. Chatt J. 383 385 413, 41 5 438 457 487. Chattanathan N. 108. Chatterjee A. 410 505. Che M. 247. Cheetham N. 351. Chekanova V. D. 294. Chekun A. L. 323 Chelnokov L. P. 365. Chen E. 92. Chen H. 91 344. Chen H. L. 31 106. Chen L. S. 488 501. Chen Y.-N. 161. Cheney A. J. 448 449. Cheney B. V. 23. Cheng Wan. 473. Cherkasova T. G. 424. Cherry I. 339. Cherwinski W. J . 453. Chesick J. P. 23. Cheung C. S. 269. Cheung K. K. 476. Chevalier P. 3 1. Chew K. F. 317. Chiang Y. 104 106 110. Chick B. B. 27. Chien J. C. W. 377. Chiesi Villa A. 351. Chini P. 447 469. 441 486. 179. Chiocola G. 442. Chiramongkol S.204. Chisholm M. H. 406 440, 449 453 462. Chivers T. 328. Chizhikov D. M. 350. Chlebek R. W. 500. Chmelnick A. M. 91 502. Chojnacki H. 91 339. Cholod M. S. 108. Chon H. 245. Choo K. Y. 299. Choppin G. R. 505. Cho Shi Thuong. 203. Chou S. S. 192. Chow Y. M. 311. Christau H.-J. 321. Christe K. O. 358 359, Christensen J. J. 91 255. Christie M. I. 149. Christian D. F. 438. Christian P. A. 409. Christoffersen M. R. 94. Christoffersen R. E. 23, Christol H. 321. Christophiiemk P. 324. Christov S. G. 112. ChruSciel R. 221 223. Chu C. K. 312. Chu S. Y. 23. Chu W. K. C. 109. Chua K. L. 377. Chun-che Tsai 375. Chung C. H. 44. Chupka W. A. 354 355, 361 362. Churchill M. R. 270 271, 282 343 385 413 425, 441 460 480 489.Churchill R. G. 58. Chvalovsky V. 302. Ciani G. 422. Ciapetta F. G. 195. Cichon J. 290. Ciechanowicz M. 392. Claassen H. H. 49 58, 361 362 363 384. Clack D. W. 11 90. Claeys E. G. 421. Clardy J. L. 320. Claridge R. F. C. 13 I 132. Clark A. H. 256 360. Clark D. T. 11 182 420, Clark G. M. 261 287. Clark G. R. 488. Clark H. C. 440 449 453, 462 479 488. Clark H. R. 330,403 503. Clark I. D. 165. 360. 24. 459 Author Index 5 15 Clark 3. D. 179. Clark P. A. 11. Clark R. J. H. 373 377, Clark T. C. 178 181. Clark W. D. 186. Clark W. G. 191. Clarke A. G. 150. Clausen C. A. tert. 388, Claxton T. A. 25. Cleare M. J. 392. Clegg W. 491. Cleland A. J. 427 482. Clemens J. 486. Clemente D. A. 313 372. Clementi E. 7 19 21 23.Clements W. R. 382. Clemmit A. F. 482. Clevenger E. N. 263. Clifford P. R. 461. Clough P. N. 191. Clough S. A. 336. Clyne M. A. A. 136 150, Coan C. R. 297. Coates G. E. 256. Cobb C. C. 58 362. Cobb M. A. 120,503. Cocevar C. 445,479. Cockerill A. F. 108. Cocks A. T. 188 189 190, Codell M. 247. Coe J. S. 397 506. Coggon P. 76 379. Cohen A. D. 313. Cohen H. 494. Cohen N. 29. Cohen S. C. 452. Cohen T. 114. Cohn K. 325 331. Colcough A. R. 44. Cole D. L. 505. Cole R. H. 41. Coles M. 442. Coles M. A. 257. Colin M. 294. Colin R. 156. Collie C. H. 97. Collier M. R. 407 486. Collin R. L. 329. Collingwood J. C. 404. Collins D. M. 375. Collins P. J. 395. Collins R. L. 388. Collman J. P. 390 484, Colton R. 43 1. Colussi A.J. 346. Come G. M. 185. Comes F. J. 128. 405 442. 389. 152 156 165 166. 274. 489. Cone C. 277. Confer A. H. 507. Connelly N. G. 474 491. Conner W. C. 236. Connolly J. W. D. 14. Connor J. 138 147 171. Connor J. A. 145 330, Conrow K. 92. Conroy A. P. 255. Considine J. L. 286. Conti F. 489. Contreras G. 292. Conville J. J. 422. Cook C. D. 459. Cook C. L. 315. Cook D. B. 7 8 18 24. Cook R. S. 108 109. Cooke J. 413. Cooke M. 464. Cookson P. G. 453. Cooper R. 155 180. Cooper W. F. 340. Copley D. B. 74. Copperthwaite R. G. 406. Corain B. 414 437. Corbett J. D. 334 350. Cordes L W . 330. Cordes E. H. 115. Corfield R. W. R. 398. Cormack D. 243,244. Cornford A. B. 11,340. Corriu R. J. P. 301 308, Corsaro R.D. 38. Cosgrove J. G. 388. Cosgrove R. K. 111. Coskran K. J. 321,430. Costa G. 413 419 444, Costanzo R. 413. Cotton F. A, 84 328 385, 389 392 470,472,484. Cotton S. A. 387. Cottrell C. E. 257. Couch T. W. 68. Coucouvanis D. 387. Coulson C. A. 11 135. Countryman R. 370 375, Court T. L. 357 406. Courtot P. 188. Coutts R. S. P. 419. Couzi M. 357. Covington A. K. 91. Cowan D. O. 473,474. Cowley A. H. 332. Cox A. P. 3 17. Cox B. G. 107 112 113, Cox R. H. 298 301. Coxon J. A. 150 165 166. 420,422. 507. 445. 454. 120. Coyle B. A. 362,484. Coyle T. D. 279 305. Crabtree R. H. 472. Cradock S. 298 299 482. Cradwick M. E. 396. Cradwick P. D. 292 480. Cragg R. H. 331. Craig P.-J. 452. Craik A. R. M. 446. Cram D. J.117. Crampton M. R. 105 110. Crawford J. R. 389,484. Crawford R. J. 182 185. Creaser 1. I. 500. Creffield G. K. 253. Creighton J. A. 252 298. Crevecoueur C. 24 1. Crisci P. 356. Criss C. M. 83. Crissman H. R. 261. Cristy S. S. 358. Critchlow J. E. 104. Croatto U. G. 372. Crociani B. 462 466. Cromer D. T. 13. Crone L. 504. Cronenwatt W. T. 254. Crook K. R. 36 37. Crooks J. E. 119. Cros C. 254. Crosbie K. D. 323. Cross J. B. 355. Cross N. E. 213. Cross R. J. 397 457 476, Crossing P. F. 430. Crow J. P. 429,432,433. Cruickshank D. W. J. 360. Cruse H. W. 152 156 165. Csicsery S. M. 210 21 1. Cucinella S. 285. Culbertson R. 277. Cullen D. L. 314. Cullen W. R. 308 429, 432 433,48 I 487. Cummins C. P. R. 186. Cundy C.S. 279,477,480. Cunningham B. B. 373. Cunningham J. A. 415. Cupitt L. T. 335. Curran C. 31 1. Curran R. 415. Currie C. L. 17 1. Curtis E. C. 358 360. Cutiss C. F. 154. Cusmano F. 468. Cvetanovic R. J. 239. Cyvin B. N. 477. Cyvin S. J. 58 260 340, Czaya Von R. 258. Czizmadia I. G. 22. 480. 477 516 Author Index Dacre P. D. 8. Dahl A. J. 262. Dahl L. F. 263 325 422, 427,428,474,488,491. Dahlen B. 321. Dahler J. S. 183. Dahlhoff W. V. 78 412. Dahms G. 297. Dahn H. 119. Dakternicks D. R. 77. Dalby F. W. 168. Dalley N. K. 372. Daly J. 90 95. Daly J. D. 443. Daly J. J. 320 476. Daly N. J. 190. Damiani A. 11. Damien D. 371. Damon E. K. 168. Damrauer R. 301. Danno S. 451. Danon N. 156. D’Antonio P. 351. Darbari G.S. 39 42 97. Darensbourg D. J. 421, Darensbourg M. Y. 422, D’Arrigo G. 35 36. Darwent B. de B. 131,185. Das M. K. 281 327. D’Ascenzo G. 315. Das Gupta A. 30. Dasgupta T. P. 120. Daskalova K. 351. Dass N. 336. Davenport J. 163. Davenport J. M. 32,44. David E. R. 478. Davidovits P. 129. Davidson G. 298 477. Davidson I. M. T. 178, 181 184 185 299 300, 305. 422,439 483. 439. Davidson. J. M. 491. Davidson R. B. 21 22 339. Davies A. G. 182 273, Davies B. R. 389. Davies C. G. 402. Davies C. W. 94. Davies D. A. 367. Davies G. 391 497. Davies G. R. 442 490. Davies J. 88. Davies J. A. 198 200. Davies J. E. 342. Davies M. 43 86. Davis B. R. 483. Davis C. M. 33 34. Davis D. D. 134 147 149, 254 290 301 310 502. 274 312.Davis F. A. 507. Davis J. 260. Davis R. 484. Davis R. E. 338 425,454, Davison A. 41 3 430,437. Davydov A. A. 247. Davytan 0. K. 242. Dawson J. H. J. 378. Day P. 404. Deacon G. B. 290 314, 453. Dean P. A. W. 315 332, 333 334 402. Deb D. M. 11. De Beer J. A. 433. De Boer B. G. 484. de Boer E. 255 387. de Boer J. H. 228 233. de Boer J. J. 46 1. de Bolster M. W. G. 41 1. Debye N. W. G. 313. De Carlo V. J. 155. Decinti A. 41 1. Deck J. S. 132. De Corpo J. J. 355. Dedieu A. 22. Deeming A. J. 428 450, Deeney F. A. 78. Dees K. 184 191. Deganello G. 419. Degetto S. 506. De Graff B. A. 184. de Groot M. S. 37. De Haan J. W. 188. Dehnicke K. 287 316, Deichman E. N. 294. Dejachy G. 355. De Jaegar R. 346. De Kock C.W. 367. De Kock R. L. 294 420, Delawarde E. 253. Delbaere L. T. J. 382. Delbeke F. T. 421. del Bene J. E. 22 183 336, Delhaye M. 50 355. de Liefde Meijer H. J. 471, Dellaca R. J. 426: Delmas M. 313. Del Re G. 17. De Marco R. A. 317. De Mare G. R. 190. De Mauduit Y. 343. Demazeau G. 378. de Meester P. 74. Dement’ev A. P. 356. Dempf D. 478. 486. 460. 411. 421 423. 357. 478. Dempsey E. 21 5. Demtroder W. 155. Demuynck J. 21. Demykina T. K. 305. Deneux M. 334. Denisov N. 366. Denisovich L. I. 474,476. Dennenberg R. J. 422. Denney D. B. 329. Denning R. G. 404. Dent A. L. 236,239. Deorani S. C. 34 35. de Pasquale R. J. 463. DePaz M. 338. Deprun C. 366. Derbyshire W. 317. Derderian C. 328. Deren J. 221 222 223, Dergunov Y.I. 31 1. Derkach G. I. 323. Dernier P. D. 368. Derwent R. G. 154 155. Derynck J. 353. de Santos R. 1 1 1. de Sorgo M. 156. Dessy G. 74 376 414. Destriau M. 232. Deubzer B. 490. Devaquet A. 22. Devarajan V. 260. de Vasconcelos M. H. 31. Devaud M. 313. Deverell C. 89. Devi A. 279. de Villiers J. P. R. 368. de Vries A. E. 30 3 1. de Vries J. L. K. F. 387. Dewar M. J. S. 7 10 182, 186 187 277 281 285. Dewkett W. J. 266. Dexter A. R. 41,43. Dey K. 312. Dezsi I. 496. Dhamelincourt P. 355. Dharmawardena K. G., Dhingra A. K. 183. Dias A. R. 472 491. Dickens D. 187. Dickson D. R. 171. Dickson R. S. 285 486. Dickson S. J. 103. Di Dio E. 505. Diebler H. 120 505. Diehl L. 309. Diemann E. 380. Diemert K.324. Diercksen G. H. F. 22, Dierks H. 265. Diesen R. W. 354 358. 225 228. 386. 336 Author Index 517 Dietrich H. 265. Dietz E. A. jun. 319. Dijkstra G. 320. Dillard C. R. 313. Dillard J. G. 345. Di Lonardo G. 344. Dilworth J. R. 385. Di Martino A. 469. Dimitrov C. 213. Dinsmore L. A. 322. Dinu A. 245. DiSalvo F. J. 378. Distrian M. 247. Ditchfield R. 22. Ditta G. S. 269. Ditter W. 337. Divald S. 507. Dix D. T. 257. Dixon J. E. 107. Dixon R. N. 10 155 168, Djordevic C. 378. Dmitrienko G. I. 188. Do J. 191. Dobbie R. C. 168 324, Dobbs B. 452. Dobosh P. A. 10. Dobson G. R. 423,481. Dobson J. E. 447. Dodd D. 31 1 445 458. Dodd J. N. 133. Dodds A. 261. Dodds J. L. 8. Dodgen H. W. 502. Dodonov A. F. 356. Dodson R.W. 293. Dodwell C. 180 182. Doedens R. J. 73 444. Doemeny P. A. 366. Dogra S. K. 156 359. Doi Y. 247. Do Kim Tuong 36 1. Dolcetti G. 390 484. Dolezar J. 497. D’Oliesager W. 505. Dollimore D. 249. Dolman D. 108. Domanov V. P. 365. Domka F. 356. Donald D. S. 296. Donaldson J. D. 3 15,481. Donaldson P. B. 410 488. Donini J. C. 79. Donohue J. 331. Donovan R. J. 124 140, 142 144 145 148 149, 152 155 156. Doorakian G. A. 310. Dorer F. H. 191. Doretti L. 469. Dorfman L. 126. 171. 431. Dorgelo G. J. H. 249. Dorm E. 402. Dornberger E. 469. Dorokhov V. A. 281,284. Doron V. 315 374. Dorosinskii A. L. 285. Dosser R. J. 55. Dostal K. 351. Douglas A. E. 138. Douglas W. E. 491. Douglas W. M. 432. Dove M. F. A. 357,406.Dowd P. 189. Dowell C. A. 340. Downey G. D. 363. Downs A. J. 334 353. Doyennette L. 30. Doyle M. P. 498. Doyle W. T. 338. Dozsa L. 498. Drager M. 297. Drake J. E. 260 285 298, 299 300 307 312. Dresdner R. D. 255. Drew M. G. B. 322 380, Drifford M. 358. Drost-Hansen W. 338. Drozd G. I. 319. Druce P. M. 279. Drullinger L. F. 345. Drummond I. 270 307. Druzhkov 0. N. 290. Drysdale D. D. 124. Dubinin M. M. 204. Dubois I. 168. Dubov S. S. 319. Dudkin V. A. 129. Dudley R. J. 73. Duesler E. N. 45 1. Duff J. M. 301. Duffaut N. 301. Duke A. J. 22. Duke B. J., 15. Dumler J. T. 480. Dumora D. 405. Dunbar R. C. 260. Duncan C . K. 164. Duncan L. C. 345. Dunks G. B. 273. Dunlop A. N. 177 185. Dunmur R. E. 327. Dunn F.40. Dunn J. G. 485. Dunn L. 96. Dunn P. 31 1. Dunning J. E. 264. Dunning T. H. 21 25. Dunogues J. 300 301. Dunsmore G. 368. Duong K. N. V. 445. Dupin J. P. 300. 382 43 1. du Preez A. L. 275,415. Durham D. A. 498. Durham W. 315 374. Durig J. R. 279 331. Durland W. 390. Durmaz S. 163. Durney M. T. 490. Durst H. D. 265. Duxbury G. 168 171. Duyckaerts G. 372. Dvolaitzky M. 445. Dvofak J. 8 1. Dybina P. V. 355. Dyer A. 218. Dyrek K. 229. Dyro J. F. 40. Dzidzic I. 86. Dzierzinski M. 185. Eaborn C. 11 6. Eachus R. S. 361. Eagers R. Y. 354. Eames T. B. 279. Earley J. E. 493 497 498, Earnshaw A. 75. Easey J. F. 371. Eastmond G. B. M. 184. Eaton D. R. 187,377,502. Eaton P. E. 455. Eaton S. S. 401. Eatough D.J. 91. Ebeling W. 82 96. Eberly P. 212. Eberly P. E. jun. 202,204. Eberson L. E. 107. Ebsworth E. A. V. 298, 299 431 482. Eccleston G. 37. Edelstein S. A. 129. Eden D. 36. Eder T. W. 183. Edge R. A. 306. Edmonds J. W. 340. Edmonds P. D. 40. Edmondson R. C. 313. Edwards A. J. 334 356, Edwards D. A. 485. Edwards J. O. 339 497, Edwards L. M. 449. Edwards W. T. 409. Efimov 0 366. Efraty A. 319. Egan W. 321. Egger K. W. 177 187,189, 274 290. Egland R. J. 254. 499 504. 358 383. 500 518 Author Index Ehrenson S. 22 192. Ehrl W. 43 1. Eichler B. 295 316. Eick H. A. 258. Eigen M. 39. Einstein A. 3 1. Einstein F. W. B. 292,375, 432 435 483 486. Eisch J. J. 286 287. Eisenberg R. 381 390, 413 415 484. Eisenhut M.329 332. Eisenstadt A. 468. Ekert H.-D. 320. Ekstrom A. 495. Elbanowski M. 156. Elbaum C. 27. Elder M. 8. El Ghariani M. A. 110. Eller P. G. 398. Ellermann J. 432. Elliott N. 383. Ellis J. E. 430. Ellis P. D. 263. Ellis R. L. 11. Elmes P. S. 433. Elpiner I. E. 40. Else M. J. 437. El Shobaky G. 228 231, Elvidge J. A. 116 121. Emerson M. F. 84. Emsley J. 255 326. Encina M. V. 181 274. Endicott J. F. 391 392. Endo H. 35 85. Endrenyi L. 183. Enemark J. H. 438. Engelbrecht A. 354. Engelmann H. 485. Engelmann T. R. 271,474. Englert M. 488. Ennan A. A. 306. Enrione R. E. 279. Entine G. 339. Enwall E. 375. Epstein I. R. 259. Erasmus C. S. 368. Erginsav A. 41. Erhard K. H. L. 135. Erlich R. H. 408. Ermolaev M. I.370. Ermolenko N. F. 214. Ernst C. R. 469 474. Erokhin E. V. 382. Esafov V. I. 257. Eskola K. 365. Eskola P. 365. Espenson J. H. 495 496, Esser J. 184. Estes W. E. 79. 232. 505. Etienne J. 368. Ettore R. 428. Evans D. F. 257 441. Evans E. A. 116 121. Evans J. A. 446 454,460. Evans N. 498. Evans W. J. 270. Ewing G. E. 335. Eyges L. 13. Eyles M. K. 204. Eyre J. A. 126. Eyring E. M. 120 505. Eysel H. H. 296. Ezhov A. I. 367. Fabelinskii I. L. 35 44. Faber G. C. 485. Fahey J. A. 370. Fahim R. B. 233. Fahrenfort J. 249. Fair R. W. 144 145 156. Falconer W. E. 179 405. Faleschini S. 469. Falius H. H. 303 330. Falkenhagen H. 82 96. Faller J. W. 463 466 472. Fallon G. D. 314. Fanelli A. 39. Fanning J. C. 61. Fantucci P.447. Faraglia G. 469. Faraone F. 468. Faraone G. 449. Fares V. 376. Farnell L. F. 422. Farnham P. 390,484. Farnham W. B. 321. Farrar T. C. 361. Farrell F. J. 400. Farrimond M. S. 11 90. Fateley W. G. 57. Faucher J. P. 325. Faust J. P. 360. Fava A. 117. Fave G. 356. Favero G. 414 437. Fay D. P. 120 505. Fay E. 309. Fay R. C. 374. Fayos J. 406. Fazakerley G. V. 257,441. Fealey T. 499. Fedorov L. A. 272,463. Fedoseeva A. S. 327. Fee W. W. 504. Feher F. 299 307 341. Fehlhammer W. P. 455. Fehlner T. P. 189 260. Fehsenfield F. C. 338,345. Feilner H. D. 491. Felder P. W. 314. Feldl K. 295 422. Feldman E. V. 345. Felkin H. 321. Fell D. S. 368. Fenderl K. 422 429 487. Fendler E. J. 11 1. Fendler J. H. 110 111.Fengor J. 388. Fennessey J. P. 413. Fensham P. J. 233,234. Fenske R. F. 420 423. Fenton D. E. 255 313. Fenwick J. T. 289. Fereday P. L. 403. Fereday R. J. 73. Ferguson J. 66. Ferguson J. A. 434 474. Ferguson K. C. 177. Fergusson E. E. 338. Fergusson J. E. 396. Fernandez-Prini R. 89. Fernando Q. 376. Fernandopulle M. E. 294. Ferrari G. E. 435. Ferrari R. P. 426. Ferraro J. R. 47 363 393. Ferris L. M. 370. Ferroni E. 382. Ferry J. D. 27. Feser M. F. 348. Fessenden R. W. 340. Fialkov A. S. 294. Fiat D. 91 502. Fidenzi R. 11. Fieggen W. 289. Field D. S. 313 489. Fieldhouse S. A. 427 482. Fields R. 437. Fields R. O. 292. Figgins R. 44. Figgis B. N. 61 62 66 69, Figurova G. N. 333. Filler R. 362. Filseth S. V. 142 144 163, Finch A.84 331. Findlay D. M. 188. Fine J. 13 1 . Fink E. H. 155. Finkel’shtein A. I. 296. Finney J. L. 339. Finnigan D. J. 317. Fischer E. O. 423 431, 439 440 469 477. Fischer H. P. 1 18. Fischer M. S. 257. Fischer R. D. 439. 71. 164 Author Index 5 19 Fisher A. 116. Fisher H. F. 88 337. Fisher I. Z. 337. Fisher K. J. 407. Fisher L. R. 339. Fisher R. D. 115. Fitch J. W. 461. Fite W. L. 127. Fittipaldi F. 39. Fitzgerald P. H. 104. Fitzpatrick N. J. 420. Fitzsimmons B. W. 276, Fixman M. 36. Flank W. H. 205. Flatau K. 252 41 1. Fleischer E. B. 394 410, Fleischmann R. 436. Flesch G. D. 422. Fletcher E. A. 355. Fletcher R. 25. Fleury P. A. 33. Flid R. M. 451. Flinn J. M. 34. Flint C. D. 406. Flint W.L. 88. Flockhart B. D. 213 346. Flood T. C. 301. Flores D. P. 461. Flowers M. C. 175 187. Fluck E. 326. Flygare W. H. 345. Flynn J. J. 314. FOB M. 429. Foester R. 331. Fogelman J. 461. Fogg P. G. T. 505. Fokina Z. A. 352. Folkers J. B. 67. Foner S. 80. Fong C. W. 310. Font J. 190. Fontaine C. 445. Foong S. W. 504. Foot K. G. 274. Ford B. F. E. 313. Ford G. H. 78,412. Ford N. C. 35. Ford P. C. 265 415. Foresti-Serantoni E. 329. Forgaard F. R. 286. Forrest K. P. 476. Forsberg J. H. 369. Forsellini E. 398 448. Forsen S. 355. Forst W. 176. Forster D. 425. Forster L. S. 71. Fortunatov N. S. 352. Foss O. 352. Foss W. 276. 406. 504 505. Foster M. J. 35. Fouassier C. 405. Fournier J. 257. Fournier M. T. 257.Foust A. S . 427 473. Fowler F. W. 105. Fowles G. W. A. 373 380, Fox M. 102. Fox M. F. 90. Fox W. B. 277 297 329, Fraenkel G. 257. Frainnet E. 300. Frais P. W. 384. Franchuk T. M. 336. Francis B. R. 256 472. Francis J. N. 270. Franck E. U. 357. Frank H. S. 88 106. Frankel L. S. 502. Franklin J. L. 355. Franz D. A. 268. Fraser G. W. 323 354. Fratiello A. 290 372 502. Frazier D. 374. Freeburger M. E. 298. Freedman H. H. 310. Freeland B. H. 427 482. Freeman C. G. 131 132. Freeman J. M. 306 325, Frend M. A. 184. Frensdorff H. K. 255. Frenzel C. A. 344. Freude D. 219. Freund R. S. 335. Frey H. M. 177 183 185, Frey R. A. 358. Fricker H. S. 15. Fridmann S. A. 189 260. Friedman A. M. 366. Friedman H. L. 84 85 90, Friedman R.M. 334. Friedrich A. 188. Frilette V. J. 200. Fripiat J. J. 214. Fritz G. 300. Fritz H. P. 293. Frohlich H. 300. Frolov S. I. 275. Frommer M. A. 339. Frost A. A. 23. Frost D. C. 11 298 340. Frye C. L. 305. Frye R. S. 334. Funfschilling O. 38. Fuger J. 372. Fujii S. 209. Fujimoto T. 176. 441. 331. 430. 187 188 189 190. 94 96 105. Fujita H. 18. Fujita Y. 331. Fujiwara F. Y. 358. Fujiwara S. 398. Fujiwara Y. 451. Fullarton A. 421. Funabiki T. 464. Funderburk L. H. 118. Fung B. M. 478. Fung H. L. 107. Fuoss R. M. 95. Furlani C. 376 383. Furness A. R. 489. Fursenko I. V. 320. Fursov P. D. 40. Furrer J. 48 1. Furukawa J. 301. Fuss W. 282. Gabe M. K. 338. Gadaibaev U. 42. Gafner G. 348. Gafney H.D. 399. Gafurov K. M. 244. Gaidis J. M. 298 Gaines D. F. 263. Gajewski J. J. 187. Galasiewicz Z. M. 361. Galembeck F. 491. Galich P. N. 209 210. Galkin N. P. 345 404. Gallagher J. J. 336. Gallagher M. J. 319. Gallazi M. C. 466. Gallezot P. 218. Galloway G . L. 267. Galwey A. K. 395. Gambino O. 426. Gamble F. R. 378. Gan L. H. 110. Ganelina E. Sh. 352. Gangi R. A. 22. Ganguli K. K. 75. Ganis P. 282 398. Gans P. 57 504. Gar T. K. 309. Garanin V. I. 195 212. Garber H. K. 383. Garbesi A. 117. Garbett K. 385. Garcia de la Banda J. F., Garcia-Fernandez H. 341. Gard J. A. 199 200. Gardes D. 366. Gardiner D. J. 340 359. Gardiner R. G. 338 387. Gardner A. W. 94. Gardner C. L. 336. 244 520 Author Index Gardner E. R.106. Gardner P. J. 84. Gardner R. F. G. 243, Garland C. W. 36. Garland F. 35 39. Garland J. K. 193. Garner C. D. 252 41 1. Garner C. S. 379 499, Garrett P. M. 269 272. Garrou P. E. 333. Garstang R. H. 142 154. Gasiewski J. W. 496. Gaspar P. P. 134 299. Gasparrin F. 448. Gassman P. G. 456 457. Gatehouse B. M. 382. Gates P. N. 331. Gatteschi D. 41 1. Gattow G. 297. Gaudemer A. 445. Gausmann H. 412. Gauthier M. 164. Gauvin H. 366. Gavrilenko V. V. 285,290. Gaylor J. R. 397. Gebala A. E. 394. Gebbie H. A. 337. Gedeon A. 129. Gedynin V. V. 272. Gee R. J. D. 482. Geibel K. 320 451. Geier G. 368. Geiger W. E. 270. Gel’fman M. I. 461. Gelius U. 21 459. Gel’man A. D. 500. Gelsema W. J. 496. Gencher S. A. 267. Gennari E.41 1. Genson D. W. 23. Genthe D. 339. Gentien E. P. 127. Geoffroy M. 346. Georgakakos J. H. 179, George C. 35 1. George J. E. 461. George T. A. 483. George 2. M. 212. Georgiev Z. L. 112. Georgiou D. 451. Gerding H. 289. Gerega V. F. 3 11. Gerlach D. H. 488. Gerloch M. 61 62 64 65, 66 67 68,69,70 78 369, 411. 244. 503 504. 191. Gerlock J. L. 106 255. Gerschler L. 303. Gershenzon Yu. M. 356. Gersmann H. R. 109. Gerson F. 319. Gerval P. 300. Geske K. 319. Gettins R. B. 218. Gewurtz S. 32. Ghiorso A. 365. Giannocaro P. 478. Giannotti C. 445. Gibb J. 179. Gibb T. C. 389. Gibbons A. R. 187. Gibson D. H. 464. Gibson J. A. 305. Gibson J. F. 387. Gick W. 323. Gielen M. 313. Gieren A. 370. Giering W. P.475. Giese K. 86. Giese R. F. jun. 254. Giesen K. P. 303 330. Gigli S. 11. Gil-Av E. 460. Gilbert A. S. 338. Gilbert J. C. 187. Gilchrist A. B. 486. Giles N. 277. Gill D. S. 479. Gill J. B. 416. Gillard R. D. 392 404, 415 449 501. Gillardeau J. 355. Gillespie J. 109. Gilles L. 360. Gillespie P. 324. Gillespie R. J. 315 332, 333 334 340 350 356, 362. 402. Gilliam 0. R. 356. Gillier-Pandraud H. 258. Gilligan M. F. 190. Gillson J. L. 396. Gil’manshin G. G. 265. Gilmore C. J. 455. Gilpatrick L. O. 280. Gilpin R. 142 336. Gilson T. R. 52 35 1. Gimarc B. M. 259. Gimyatullin N. G. 265. Ginderow D. 294. Gingerich K. A. 284. Ginns I. S. 3 16. Ginsberg A. P. 76,77,394, 414 488 489. Ginsberg H. 104. Girard C. 432. Girshkov A.Ya. 336. Gislason J. 292. Gisquet E. 232. Gisser H. 247. Gitis M. B. 34. Gitter A. 118. Glass G. P. 335. Glebov V. A. 371. Glemser O. 3 18 328 348, 349 350 382. Glentworth P. 369. Glew D. N. 337. Glick M. D. 286 368. Glidewell C. 299,302 306, Glinka K. 341. Glockling F. 259 482. Glogowski M. E. 275. Glonek T. 329. Glover G. M. 42. Glucckauf E. 89 94. Glyde R. W. 452. Goates J. R. 253. Goddard N. 299. Gohausen H. J. 304. Goel A, 336. Goel R. G. 313 315 332. Goetz G. 334. Goetze U. 290. Goffin N. 313. Gold K. 270. Gold V. 105 116 118, Goldberg S. Z. 451. Golde G. 177. Golden D. M. 176 177, Golden R. 277 281. Goldfinger P. 190. Golding B. T. 465. Goldschmied E. 410. Goldstein M. 43 3 14 31 5. Goldstein M.S. 203. Golik G. A, 323. Gollogly J. R. 404. Golz K. 305. Gombler W. 340 344. Gomm P. S. 396 397. Gondal S. K. 45 1. Good M. L. 388 389. Goodacre G. W. 322. Goodall B. L. 444 446. Goodall D. C. 4 16. Goodfellow R. J. 464. Goodgame D. M. L. 73, Goodman B. A. 311,481. Goodman H. 176. Gorbachevskaya V. V., Gordimer G. 494. Gordon A. S. 190. Gordon J. E. 355. Gordon J. G. 289. Gordon R. G. 161. Gorenbein E. Ya. 358. Goring G. E. 31. 307 317. 119. 182. 74 77 376. 442 Author Index Gornall W. S. 32. Gornowicz G. A. 254, Gosavi R. K. 156. Gosh S. 497. Gosling K. 287. Gottardi W. 295 296. Gotthardt B. 342. Goubeau J. 281. Govil G. 11. Gowenlock B. G. 181. Grace M. 266. Graham D. 306. Graham D. M. 179. Graham M.A. 421. Graham R. C. 120. Graham W. A. G. 425, 452 473 476 481. Grahn R. 90. Grant D. M. 322. Grant M. W. 119 503. Grasdalen H. 288. Grassino S. L 280. Gravelle. P. C. 228. 231, Graves G. E. 326. Gray C. E. 254. Gray C. G. 357. Gray H. B. 54 79 394, Gray N. A. B. 12. Gray P. 176 179. Gray T. J. 246. Graziani M. 343 485. Graziani R. 398 448. Greatrex R. 388 389,433, Greco A. 454 467. Green J. A. 132. Green M. 282 433 454, 460 464 477 486 494. Green M. L. H. 321 440, 447 457 463 464 471, 472 477 479 490 491. 304. 232. 249. 421 473 474 479. 434 48 1. Green P. J. 430. Green S. 22. Greene P. T. 314 422. Greenwood N. N. 264, 285 288 311 369 387, 388 389 433 434 481. Gregory V. A. 444. Gregson A. K. 75. Greig G.133 147 156. Greiner N. R. 155 180. Greiss G. 281 476. Grellier P. L. 102. Grevels F.-W. 467. Grey I. E. 75 384. Gridasova R. K. 367. Griffith N. P. 392. Griffith W. P. 252 367. Griffiths J. E. 345. Grigor’eva V. S. 3 15. Griller D. 274. Grimes R. N. 268 269. Grimm F. A, 155. Grimm L. F. 325. Grimmelmann E. K. 23. Grinblat M. P. 312 328. Grisdale P. J. 275. Grist S. 105 116. Grobe J. 319. Groeneveld W. L. 41 1. Gromov V. V. 351. Gropen E. 11. Groszek E. 268. Grotens A. M. 255. Grotewold J. 177 181, Groth W. 137 141 161. Grover J. L. 358. Groves D. 253. Groz P. 361. Gruen D. N. 367. Grundke H. 273. Grunwald E. 103 105. Grupe K. H. 498. Gsell R. A. 310. Guastalla G. 435. Gubin S. P. 474 476. Gubnitskaya E.S. 323. Gueilleron. J 284. Guelton M 240. Guengart L. 35. Giinther T. 300. Guerchais J.-E. 376. Guertin J. P. 358. Giisewill D. 33. Guest A. 384. Guest M. F. 330. Guggenheim E. A. 97. Guillery R. 299. Guillory W. A. 307. Gumboldt A. 419. Gunning H. E. 144 156, Gupta K. S. 293 498. Gupta P. N. 33. Gupta R. R. 298. Gupta S. K. 261,273,277, Gupta V. D. 385. Gupta Y. K. 293 356, Gurevich M. Z. 367. Gurikov Yu. V. 337. Gusev Yu. K. 363. Guss J. M. 446. Guthrie D. J. S. 466. Guthrie R. D. 115. Gutman D. 355. Gutmann V. 252. 273 274. 181. 344. 498. 52 1 Gutschick V. P. 36. Guyon P. M. 354 362. Gvishi M. 241. Gysling H. 419. Gyulai J. 227. Haag A. 320. Haaijman P. W. 228. Haake M. 348. Haaland A. 256 285 286.Haas A, 296 297. Haas C. K. 298. Haberfield P. 104. Habgood H. W. 212. Hadii D. 333. Hadicke E. 45 1. Hassler H. 38. Hagelberg M. P. 33. Hagenmuller P. 254 378, Hagihara N. 451. Hagiwara E. 248. Hague D. N. 101 120, Hahn H. 254. Haigh I. 380. Haight G. P. j u n . 378, Haim A. 493. Haines L. M. 488. Haines R. J. 275,433,434, Hair N. J. 325. Hajdu J. 258. Hakin V. A. 361. Halasa A. F. 254. Hale P. K. 404. Hall D. 276 375 396. Hall J. R. 476. Hall L. 34. Hall L. D. 368. Hall R. E. 115 283. Hall R. J. 505. Hall W. K. 213. Halle M. 168. Hallgren J. E. 426. Halpern J. 275 392 419, 424 435 444 452 455, 499 500. 405. 503. 496. 475. Halvorsen S. 285 Ham F. S. 65. Hamada S. 342. Hamann S. D. 387. Hambright P.252 410, Hamelin J. 182. Hamilton A. 415. Hamilton W. C. 380. Hammer G. P. 207. 506 522 Hammes G. G. 40. Hammond B. 399. Hammond G. S. 421. Hammond P. R. 345. Hamrin C. E. jun. 345. Hamrin K. 459. Hamson R. E. jun. 144. Han P. Z. 329. Hanazaki I. 396. Handler V. 476. Handy L. B. 325,422. Hankin D. 21 91 362. Hanlon T. L. 466. Hanna E. M. 95. Hanna S. B. 498. Hanousek F. 265. Hansen A. E. 71. Hansen H.-J. 188. Hansford R. C. 210. Haque F. 473. Hara N. 209 21 1. Haraguchi H. 398. Hardin C. V. 297. Harding M. J. 404. Hargittai I. 382. Hargittai M. 382. Harlem M. 356. Harman J. S. 325 326. Harmony M. D. 316. Harned H. S. 98. Harreld C. S. 315. Harris C. M. 77. Harris F. E. 8 19. Harris G. M. 120.Harris H. H. 193. Harris J. 365. Harris J. M. 1 1 5. Harris R. R. 24. Harrison J. F. 183. Harrison P. G. 281 309, Harrison W. 290 326 435. Harrison W. B. 301. Harriss M. G. 297. Harrod J. F 374. Harrowfield J. N . Mac B., 404. 504. Hart B. T. 7. Hart F. A. 257 369. Hart-Davis A.-J. 452,481. Hartley D. 56. Hartley F. R. 419. Hartmann V. 340. Hartshorn L. G. 141 336. Hartter D. R. 296. Harvey K. B. 265. Hasalbach E. 7. Hase W. L. 185. Haselbach E. 182. Hasinoff B. B. 119 503. Hassel R. L. 412. Hasted J. B. 97 339. 3 12 327. Hastie J. W. 369 405. Haszeldine R. N. 306, 437 450 453. Hatfield W. E. 61 68 73, 74 75 77 78 79 390, 404. Hathaway B. J. 73 77. Hathaway E. J. 258. Hathorn F. G. M. 149, Hatzenbuhler D. A.156. Haubold W. 277. Hauffe K. 229 244. Hauge R. H. 369 405. Hauge S. 351. Haugen G. R. 176 189. Haupt H. J. 294. Haus J. W. 32. Hautecloque S . 179. Hawkins C. J. 403 404. Hawley S. 34. Haworth D. T. 283. Hawthorne M. F. 261, 269 270 271 272 273, 455 507. 171 173. Hay J. N. 286. Hay R. W. 507. Hayata S. 214. Hayek E. 258. Haymore B. L. 255. Hazony Y . 361. Heal G. R. 249. Heal H. G. 341. Healey P. C. 386. Healy J. D. 322. Heath C. 406. Heath D. C. 57. Heath G. A. 413 414. Heaton B. T. 392 501. Hebecker C. 315. Heck R. F. 459. Heckl B. 439. Heckner K. H. 498. Hedberg K. 265. Hedgeland R. 328. Hedges R. E. M. 132 155. Hehre W. J. 22. Heil H. F. 281 476. Heil T. G. 22. Heimgartner H. 188. Heinsen H.-H.380. Heinz D. 329. Heitz C. 363. Helling J. F. 477. Hemingway J. D. 366. Hemmes P. 39 505. Hemmings R. T. 307. Hempel H.-U. 487. Hempel J. C. 79. Henderson W. G. 318. Hendrickson D. N. 79, 473 474. Author Index Henfling D. 187. Hengge E. 299 302. Henrici-Olive G. 376,419, Henry P. M. 458. Henry R. P. 376. Henzel R. P. 455 456. Hepler L. G. 375. Herber R. H. 31 1 361. Herbert A. P. 92. Heberhold M. 439 459, 485. Herberich G. E. 275 281, 468 475 476. Herlinger A. W. 444. Herman F. 13. Hermanek S. 265. Hernandez J. 273. Herod A. A. 179. Herold A. 294. Herraez M. A. 507. Herring F. G. 11 72 298, Herrmann E. 326. Herron J. T. 124. Hersh K. A, 313. Hertel H. 324. Hertz H. G. 82 83 85. Herzberg G. 155 168 Hess R.E. 298. Hesse K.-F. 306. Hessett B. 283 373. Hessley R. K. 498. Hester R. E. 91. Heumann W. R. 254. Hevesi I. 227. Hewitt T. G. 298. Hewson M. J. C. 325. Heyman M. 407. Heyns A. M. 265. Hibbert F. 11 3. Hickel B. 360. Hickson D. A. 210. Hidai M. 447. Highberger G. 88. Highsmith R. E. 302. Higson B. M. 78. Higuchi T. 107. Hikida T. 126. Hill H. A. O. 396 445. Hill J. O. 375. Hill M. N. S. 484. Hill N. J. 73. Hill R. E. E. 367. Hill R. J. 97. Hillier I. H. 21 260 330, 340 420. Hills G. J. 81 92. Hine J. 107 108. Hinkley R. K. 21. Hinshaw W. S. 279. 506. 340 429. 172 183 Author Index Hirabayashi T. 288. Hiraishi J. 59. Hirota Y. 491. Hirsch. W. 92. Hirschfelder J. O. 154. Hirschler A. E. 201. Hirst D.M. 11 15. Hitch R. R. 451. Hitchcock P. B. 449. Hitchman M. A. 77. Hlasivcova N. 498. Ho H. F. 331. Hoard J. L. 375. Hoare R. J. 446. Hobbs M. E. 121. Hobday M. D. 315. Hobdell M. R. 254. Hoberg H. 288. Ho Chi Thanh. 203. Hodges R. H. 455. Hodgson D. J. 77 404. Hodgson K. O. 478. Hofer R. 350. Hofler M. 431. Hoehle T. 343. Hoekstra P. 338. Hoering T. C. 345. Hoffman B. M. 279. Hoffman D. C. 366. Hoffman M. Z. 391. Hoffmann E. 252. Hoffmann P. 324. Hoffmann R. 18,182 186. Hogarth M. J. 102. Hogfeldt E. 109. Hogg J. H. C. 290. Hoggard P. E. 502. Hohnstedt L. F. 276. Hohorst F. A. 297. Holbrook K. A. 265. Holding A. F. Le C. 481. Holland R. J. 479. Hollebone B. R. 403. Holleman G. W. 171. Holliday A. K. 273 279.Holliday R. I. 245. Hollis P. C. 7. Hollister C. 21 362. Holloway C. E. 374 461, 484. Holloway J. H. 311 338, 352 354 358 361 362, 384 405. Hollyhead W. B. 109. Holm D. A. 498. Holm R. H. 252,289,401. Holmberg R. W. 297. Holt S. L. 267. Holton G. 34. Holtz D. 318. Holtzer A. 84. Holywell G. C. 325 430. Homer G. D. 301. Honig J. M. 241. Hoogland J. G. 344. Hooper M. A. 53 59. Hooper P. G. 286. Hooper T. R. 342. Hooton K. A. 491. Hope H. 358. Hopkins D. E. 184. Hopkins R. G. 188. Hoppe R. 252 314 397, Hoppe W. 370,451. Hopper J. R. 212. Hordis C. K. 287. Horlbeck G. 468. Hornback C. J. 21 24. Horne D. G. 124 155, Horne R. A. 336. Homer S. M. 331. Horrocks W. De W. jun., 367 378 386. Horsfield A. 474. Horsley J.A. 21. Hosaka A. 193, Hosegood E. A. 379. Hoshi M. 372. Hoskins K. 449. Hota N. K. 272. Hou F. L. 432. House D. A. 503 504. Howarth D. T. 396. Howatson J. 256. Howe A. T. 387. Howe D. V. 271. Howell B. F. 338. Howell J. A. S. 376. Howie R. C. 289. Howlett K. D. 322 326. Hoxmeier R. 490. Hoyano J. K. 473. Hrycyshyn. E. S 128. Hsia K. L. 95. Hsieh A. T. T. 291 292, 427 480 491. Hsu K. 22. Huang T. J. 378 496. Hubbard P. S. 279. Hubberstey P. 253. Huber H. 49. Huber M. 432. Hudson A. 181 384. Hudson B. E. 287. Hudson H. R. 323. Hudson K. 110. Huebel J. 345 346. Hiiber H. 351. Huetz-Aubert M. 3 1. Huffman R. E. 164. Huggins M. L. 252 278, 400. 156 171. 336. 523 Hughes M. N. 316. Hughes R. E. 287 309, Hughes R.P. 466. Hull S. E. 452. Hulme R. 332. Hulscher J. B. 320. Hume D. N. 280 Hummer D. G. 127. Humphreys D. A. 332. Hunston D. L. 121. Hunt A. H. 121. Hunt G. W. 330. Hunt J. P. 502. Hunten D. M. 137. Hunter B. K. 405. Hunter D. H. 462. Hunter F. D. 198 205. Hunter G. 292 294. Hunter J. L. 32 44. Hunter T. F. 90. Huntziker H. E. 132. H u q F 443. 491. Hurst G. S. 131. Hursthouse M. B. 331, Hurtubise F. G. 131. Husain D. 124 134 135, 136 137 140 142 144, 145 148 149 152 154, 155 156. 473. 406. Hush N. S. 84. Hussey M. 40. Hussonois M. 365. Huston J. L. 58 363. Hutchings M. G. 261,275. Hutchins R. O. 265. Hutchinson B. 380 487. Hutchinson J. R. 289. Huttner G. 477 480. Hutton R. S. 183. Huybrechts G.190. Hyde C. L. 483. Hyman H. H. 359 362. Hyne J. B. 103. Hynes. T. V. 284. Ibekwe S. D. 443 444. Ibers J. A. 389 450 483, Ibrahim E. M. H. 322, Ichikawa K. 293 356. Ignat’eva 0. N. 499. Ikeda S. 458 483. Ikeda Y. 293. Ikeuchi I. 447. Ilgunas V. 44. Ilin E. G. 405. 484 485 486. 326 524 Author Index Llyukhin V. V. 306. Imamura A. 18. Imanaka T. 217. Imelik B. 213 218. Imhof R. E. 161. Immirzi A. 465. Inamoto N. 324. Indelli A. 11 1 360 500. Inel Y. 179. Ingold K . U. 273. Inhoffen H. H. 415. Inman G. W. jun. 77 78. Innes R. A. 236. Insley H. 280. Interrante L. V. 396. Ionescu A. 245. Ionescu M. 245. Ionova T. I. 424. Iordanov N. 351. Iorns T. V. 263. Iqbal M. Z. 444 446. Irish D. E. 91 344. Isabel R.J. 307. Isabey J. 360. Isaeva G. G. 119. Isakov Ya. I. 195 209. Isakova N. B. 31. Isakova T. 212. Ishida K. A. 11. Ishii Y. 288 331 333,482. Ishikawa M. I. 300. Isida T. 310. Isobe K. 41 1. Issleib K. 319. Isupov V. K. 363. Ito M. 339. Ito T. 332. Itoh K. 488. Ivanova Z. M. 323. Ivanov-Emin B. N. 367. Ivashin S. A. 352. Ivin K. J. 119 346. Ivin S. Z. 319 325. Iyengar R. D. 247. Iyer R. S. 193. Izatt R. M. 91 255. Izod T. P. J. 178 181. Jache A. W. 360. Jackman T. A. 494. Jackopin L. G. 86. Jackson G. E. 168. Jackson P. C. 182. Jackson P. T. 156. Jackson R. A. 181. Jackson R. B. 381. Jacob E. 355. Jacob E. L. 363. Jacob S. W. 101. Jacobs P. 205. Jacobson R. A. 320 334. Jacobus J. 332. Jacot-Guillarmod A.442. Jacox M. E. 297,3 18,343, Jacubowski E. 181. Jaffe H. H. 1 1 . Jaffe M. R. 120 505. Jagur-Grodzinski J. 106. Jain B. D. 469 478. Jakubetz W. 11. Jakubowski A. 463,472. Jakubowski E. 191. James B. D. 259 265. James B. H. 11. James B. R. 412,419,435. James D. G. L. 171 177, James F. C. 171. James T. A. 472. James T. L. 187. Janin J. 166. Janousek Z. 295. Jansen W. 303. Janssen E. 328 475. Janz G. J. 91. Janzen A. F. 305. Janzen E. G. 301. Jaques D. 109. Jarczewski A. 114. Jardine F. H. 399. Jarvis J. A. J. 255 442. Jarzynski J. 34. Jaselskis B. 363. Jaura K. L. 3 1 1. Jaworski K. 287. Jayaraman S. 352. Jeans J. 82. Jellinek F. 330 471. Jen J. 120. Jenkins I. D. 319. Jenkins R. L. 299. Jennings K. R. 136.Jensen B. N. 39. Jensen F. R. 301 310. Jensen J. H. 108. Jensen R. J. 171. Jensen S. J. K. 93. Jernigan R. T. 481. Jesaitis R. G. 12. Jesson J. P. 479 488. Jeter D. Y. 75 79 390. Jetz W. 481. Jezowska-Trzebiatowska, Jha N. K. 361. Jindal V. K. 388. Jargensen C. K. 366 368. Johans A. W. 431. Johansen H. 21. Johansson G. 459. Johari D. P. 179. 358. 186. B. 61. Johari G . P. 43. Johns J. W. C. 155 168, Johnson A. W. 410,415. Johnson B. F. G. 420, 428 432 434 460 484. Johnson C. E. 406. Johnson G. D. 92. Johnson G. L. 507. Johnson H. D. 264. Johnson J. S. 97. Johnson K. H. 13 14. Johnson M. D. 444 445, Johnson N. P. 413. Johnson R. C. 506. Johnson S. E. 156. Johnson S. N. 191. Johnston D. L. 378 386. Johnston G.F. 105. Johnston H. S. 124 156, Johnston R. D. 434 488. Johnstone R. A. W. 273. Jola M. 177. Jolicoeur C. 90 91. Jolly P. W. 447 465 488. Jolly W. L. 104 310 342. Jonas K. 447. Jonassen H. B. 61,74,459. Jonathan N. 140 165, 335 342. Jones A. 179. Jones C. E. 321 430. Jones C. H. W. 352. Jones C. J. 271. Jones D. E. H. 289. Jones E. M. 422. Jones E. R. jun. 75 78. Jones G. R. 356 361 362, Jones I. T. N. 164 165. Jones J. R. 104 109 116, Jones L. H. 59. Jones M. M. 330 403, Jones P. R. 297. Jones R. D. G. 292,435. Jones R. P. 173. Jones W. E. 503. Jonkman R. M. 30. Joo W. C. 304. Joos K. 485. Jordan P. C. 138. Jordan R. B. 411 493, Jorgensen W. L. 22. Joshi B. K. 110. Joshi K. K. 490. Jotham R. W. 72 268, 354.458. 166 168. 405. 121. 503. 502. 368 452 Author Index Jouve P. 343. Jove J. 371. Jud W. 137 141. Jung G. 487. Junge H. 55 252 41 1. Jungen M. 23. Junkes P. 330. Jurado B. 289. Jursa A. 136. Justice J. C. 95. Kaatze U. 86. Kachapina L. M. 408, Kaden T. 501. Kadibelban T. 321. Kadonaga M. 463. Kaduk B. A. 298. Kaenzig W. 335. Kaesz H. D. 428,435,490. Kaganovich V. S. 424. Kahl W. 489. Kai Y. 288. Kaizu Y. 390. Kakudo M. 288. Kaldor A. 260. Kalidas C. 108. Kalinin V. N. 119 272. Kalinina V. E. 499. Kalinnikov V. T. 470. Kaliya 0. L. 451. Kallen T. W. 497 498. Kalman A. 347 360. Kalman B. L. 24. Kaloustian M. K. 270. Kalsotra. B. L. 469 478. Kalyanaraman A. R. 390. Kamb B. 339. Kambanis S. M.186. Kambe K. 70. Kaminski W. 177. Kammel G. 348. Kammer W. E. 22. Kamp D. A. 379. Kanazirev V. 21 1. Kane A. R. 266,480,488. Kane J. 280. Kanekar C. R. 473. Kaneko M. 155. Kanellakopulos B. 469. Kang J. W. 479. Kano T. 321 448. Kantrowitz E. R. 391. Kapila V. P. 340. Kaplan M. S. 187. Kaplan R. I. 76 394. Kapoor P. N. 319. 483. Kapovits I. 347. Kapralova G. A. 356. Kapsomenos G. S. 19. Karabadzhak F. I. 304. Karaksin Yu. N. 290. Karapet M. Kh. 351. Karasawa Y. 105. Karayannis N. M. 315, Kari R. E. 22 25. Karle J. 351. Karlen U. 368, Karlin A. V. 305. Karlsson H. 319. Karpas Z. 384. Karpel R. L. 503. Karpinskaya N. M. 461. Karraker D. G. 80 369. Kartha C. G. 36. Karyakin N. V. 351. Kasai N. 288 463. Kashiwagi T.447. Kaspi P. 388 389. Kassal T. 29. Katabe K. 342. Katayama M. 31. Katcoff S. 366. Katkov N. A, 483. Kato A, 214. Kato E. 32. Kato H. 1 1 461. Kato M. 61. Kato S. 38. Katovic V. 378. Katrib A. 298. Katritsky A. R. 105. Kats B. M. 306. Katsuta M. 209. Katz L. 467. Katz T. J. 320. Katzer J. R. 216. Katzui L. I. 408. Kauffman G. M. 117. Kaufman F. 124,136,140, Kaulgud M. V. 33. Kawabata N. 301. Kawaguchi S. 41 1. Kawakami S. 209. Kawamura T. 3 10. Kawasaki K. 36. Kay A. 382. Kazanskii V. B. 218 247. Kazantsev A. V. 272. Keable H. R. 487. Kearns D. R. 155 164. Keat R. 340. Keats S. 332. Kebarle P. 86 88. Keen I. M 204. Keeton M. 410 449. 324. 474. 525 Keijser R. A. J. 30. Keil D. G. 125. Keiner V.423. Kelby G. 85. Keller P. C. 261. Keller R. N. 493. Kelly F. W. 188. Kelly H. C. 267. Kelly T. L. 392. Kelly W. S. J. 78 412. Kemball C. 213 218. Kemme A. A. 308. Kemmitt R. D. W. 397, Kemp K. A. 34 36. Kennedy M. J. de G. 384. Kennedy T. 330. Kenny N. C. 340. Kenworthy J. G. 470. Kermarec J. 213. Kern F. 437. Kerr C. M. L. 330. Kerr C. W. 160. Kerr G. T. 199 205. Kerr I. S. 200. Kerr J. A. 179 187. Kertes A. S. 252. Kesavuiu V. 239. Kesmarky S. 108. Kessel H. 303. Kessenikh A. V. 277. Kessler Yu. M. 82. Kettle S. F. A, 15 65 72, Keve E. T. 360. Key D. L. 409. Khabibullaev P. K. 32, 37 38 42. Khaliulin M. G. 32. Khalkin V. A. 361. Khamidov A. Y. 244. Khan H. A. 110. Khan S. A. 107. Khanagov A. A.338. Khand I. U. 427. Khare G. P. 413. Kharlamov V. 212. Khetrapal G. L. 473. Khidir Aljibury A. L. 358. Khuz Z. 229. Kibblewhite J. F. J. 355. Kiefer W. 352 405. Kiesewetter W. 258. Kilbourn B. T. 442 444, Kilby B. J. L. 440. Kilcast D. 11 319. Killean R. C. G. 322. Killpack D. R. 116, Kilner M. 486 487. Kilvington A. L. 366. 454. 452. 490 526 Kim H. 58. Kim M. G. 34. Kim T. S. 339. Kim Y. H. 258. Kimberlin C. N.,jun. 202. Kimura B. Y . 254. Kimura E. 392. King A. D. jun. 297. King G. H. 276. King K. D. 177. King P. W. I 1 1 . King R. B. 319 420 430. King R. C. 359. King S. T. 295. King T. C. 93. King T. J. 385. Kingham J. D. 338. Kinney R. J. 496. Kipling B. 504. Kirby A. J. 107. Kireev V. V. 326. Kirin I.S. 363. Kirkwood C. E. 76 394. Kirkwood J. G. 94. Kirsch L. J. 134 136 140, 142 145 155. Kirsch P. 42 1, Kirschner S. 182. Kisch H. 423. Kiseleva N. V. 424. Kishore J. 342 344. Kisin A. V. 309. Kislovskii L. D. 337. Kistemaker P. G. 30. Kistenmacher T. J. 67, 374. Kistiakowsky G. B. 136, 178 181 184. Kitazume S. 483. Kitching W. 310. Kite K. 449. Kiyohara O. 33. Kjekshus A. 343 360. Klaning U. K. 93. Klanica A. J. 360. Klasterbaer D. H. 155. Klebanskii A. L. 328. Klein H. F. 408 450 479, Kleinstuck R. 323. Klemann L. P. 442. Klemm R. M. 147. Klemperer W. 155. Kley D. 155 161. Klimov V. D. 345. Klimova A. I. 272. Klimova T. P. 272. Klimova T. V. 272. Klimchuk G. S. 266 328. Klinksiek G. 324. 204. 212.486 488. Kloosterziel H. 188. Klopman G. 10. Klosowski J. M. 305. Klotz I. M. 121. Kloubek J. 383. Klug W. 297. Kluess C. 406. Klusaceck H. 324. Klyuchnikov N. G. 304. Knaap H. F. P. 30. Knapp P. S. 88. Knauss L. 439. Knebel W. J. 438. Kneen W. R. 449. Kneipp K. G. 113. Knight J. 425 427 428, Knobler C. 358. Knoll F. 295. Knoth W. H. 271. Knowles P. J. 472. Knox G. R. 427,446. Knox S. A. R. 428 435. Knyazev Yu. D. 371. Knyazeva N. N. 424. KO E. C. F. 1 IS. Kobayashi H. 390. Kobayashi-Tamura H . , Kobelt D. 353. Kobrinsky P. C. 177. Koch W. 349. Kochanski E. 21. Kocheshkov K. A. 287. Kochi J. 459. Kochi J. K. 181 187 310. Kocman V. 442. Koczorowski Z. 83. Koda S. 41 1. Kodama G. 264. Kodama M 121. Koechlin F.501. Kohler F. H. 293. Kohler H. 295 316. Koehn W. 190. Konig E. 55 61 367 379, 386 412. Kopf H. 489. Koepke J. W. 428. Koeppl G. W. 91 102, Koerner von Gustorf E., Koffler R. L. 201. Kohl J. 41 1. Kohlmaier G. 191. Kokes R. J. 236 239. Koketsu J. 33 I 333. Kokot E. 78. Koksharova A. A. 275. Kokunov Yu. V. 382. Kolchin 1. K. 214. 463. 423. 115. 467. Author Index Koldtiz L. 334 405. Kolesnikov G. S. 326. Kollman P. A. 336 338, Kollmar H 1 1 . Kollmeier H. J. 439. Kolloch B. 405. Kolm H. 221. Kolobova N. E. 470. Kolodriejczyk A. 405. Kolomnikov I. S. 442. Kominar R. J. 177. Komissarova L. N. 367. Komor M. 496. Kompa K. L. 150. Kornson R. C. 72. Konar R. S. 179. Konasewich D. E. 106. Koningsberger D.C. 350. Konishi H. 22. Koob R. D. 183. Koola J. 313. Kopanev V. D. 405. Kopelman R. 56. Kopp H. 307. Kopp I. 155. Kopp J. P. 284. Kor S. K. 34. Korenowski T. F. 430. Kornegay R. 21. Korobeinikova S. A. 275. Korotkin Yu. S. 365. Kortbeek A. G. T. G. 474. Koryta J. 8 1. Kosa-Somogyui I. 339. Koser G. F. 455. Kosky C. A. 282. Kosower E. M. 258. Koster R. 281. Kostin M. D. 192. Kostiner E. 309. Kotsev N. 235. Koubek E. 77. Koutecky J. 25 244. Kouwenhoven H. W. 212. Kovar R. A. 277,283,285. Kovredov A. I. 272. Kowalak A. 503. Koyano I. 127. Kozima S. 310. Kozmutza K 362. Kraihanzel C. S 422. Kramar M. 345. Kramer P. A. 468. Krantz A. 177. Kranz H. I. 451. Krasochka 0. N. 381. Krauhs S. W. 450. Krause L.128 132. Krauss H. 339. Krausse J. 443. Krebs B. 309. 339 Author Index 527 Krebs M. 257. Kreevoy M. M. 106. Kreiter C. G. 439 440. Kremer S. 386. Kresge A. J. 91 102 104, 106 110 115. Kreuger R. H. 363. Kreuzberg G. 314. Kricheldorf H. R. 304, Kreig B. 480. Kreig V. 33 1 . Krieger J. K. 459. Krishnamurthy S. S. 276. Krishnamurty M. 504. Krishnan C. V. 84 105. Krishnan K. S. 65. Kristoff J. S. 420. Krohmer P. 281. Krohn K. A. 193. Krohn N. A. 337. Kroll W. R. 287 480. Kroon J. 320. Kroschwitz H. 326. Krot N. N. 500. Kroto H. W. 155 168. Kruck T. 487. Kriiger C. 447 467. Krueger G. J. 348. Kruger T. L. 109. Kruglova A. V. 241. Krumgals B. S. 89. Krumholz P. 409 491. Krumm U. 295. Kruse W. 293. Krusic P. J.181 187. Krutkina M. N. 405. Krylova G. P. 351. Krylova I. V. 248 249. Kryzhanovski B. P. 241. Kubasov A. A. 21 1. Kubasova L. V. 329. Kubilyunene O. 44. Kubo V. 372. Kubota M. 452. Kuc T. A. 460. Kuchen W. 324. Kuck V. J. 183. Kuckertz H. 353. Kuczkowski R. L. 276, Kudryavtsev R. V. 483. Kuhl G. H. 208. Kuhlman D. P. 451. Kuhlmey J. 43 1 . Kuhr M. 252 41 1 . Kuita Y. 218. Kulasingham G. C . 55. Kulishov V. I. 470. Kumada M. 300 482. Kumar K. 37. Kumar L. 19. 346. 3 18 320. Kumar Das V. G. 315. Kummer D. 309,481. Kundu K. 108. Kunsitis-Swyt C. R. 32. Kuntz I. D. 104. Kuntz P. J. 192. Kuntz R. R. 179. Kunwar A. C. 473. Kunze U. 313. Kuppermann A. 1 1 1. Kurimoto R. K. 379. Kurimura Y. 494. Kurosawa H. 294 479.Kuroya H. 41 1 . Kurylo M. J. 126 342. Kurzel R. B. 156. Kustin K. 503. Kustodina V. A. 355. Kutschinski J. L. 301. Kuwana T. 496. Kuzin V. I. 361. Kuznetsov N. T. 266 328. Kvasnitka V. 12. Kvasova L. E. 32. Kvite G. 142. Kvlividse V. I. 388. Kwan T. 240 245 331. Kwart H. 114. Kyachenko Y. F. 35. Labarre J. F. 330. Labarre M.-C. 325. Labes M. M. 315 324. La Bonville P. 363. Labrone D. 435. Lacey M. J. 395. Lachance A. 293. Lachi M. P. 425. Lacout-Loustalet M. B., Ladd J. A. 254. Ladenburg R. 132. Ladik J. 17. Lagenaur C. 115. Lagercrantz C. 3 19. Lagowski J. J 283 316. Lahet G. 284. Lahournere J. C. 300. Laidler K. J. 182 184. Lakeman M. 206. Lakhuary M. E. 247. Lakshmanan S. 97. Lalancette J. M. 293.Lalancette R. 383. Lallemand P. 44. Lalor F. J. 261 471 486, Lalonde A. C . 185. Lam E. Y. Y. 134,299. 300. 507. La Macchia J. T. 43. La Mar G. N. 379. Lamb J. 37 41 43. Lambert C. A. 178 185, Lambert J. D. 29 124. Lamberton H. M. 155, La Monica G. 452 486, Lamont A. M. 187. Lamper J. E. 108. Lan C. 345. Lancaster J. 338. Lancaster J. C. 402. Lancaster J. M. 388. 499. Land J. E. 497. Landa B. 72 362. Landau L. 135. Landau M. A. 319. Landesberg J. M. 467. Landis P. S. 195 217. Landsberg R. 498. Lane B. C. 392. Lane C. F. 274. Lane R. H. 493. Lanewala M. A. 208. 210. Lang G. 385. Lang J. 40. Lang W. H. 215. Lange S. 477. Langley K. F. 141 142. Langley K. N. 35. Langlois G. E. 207. Langs D. A. 346. Lanshina L.V. 32 38. Lanthier G. F. 276 280. Lapouyade P. 301. Lappert M. F. 276 279. 302 407 441 486 400. Large N. R. 369. Larin G. M. 470. Larkin G. A. 438. Larkin R. H. 353. Larking I. 382. Larkins F. P. 233,234. Larkworthy L. F. 78 377, Larmande M. T. 44. Larrabee J. C. 164. Larsen J. W. 110. Larson C. W. 179. Larson E. V. 33 34. Larson G. 28. Larsson R. 404. Laruelle P. 368. Lascelles K. 378. Lascombe J. 357. Lassman E. 349. Latham W. A. 22. Latimore M. C. 114. Latta J. C 395. 300. 168. 489. 409 Author Index Lattimer R. P. 316. Laube B. L. 252. Laubereau P. G. 469. Lauder W. 331. Laufer A. H. 335. Laulicht I. 56. Laver W. 332. Lavercomb B. L. 30. Lavrenova L. G. 355. Lavrinovich L. I. 284. Lavroskaya G.K. 356. Lawless E. W. 334. Lawrence F. O. 366. Lawrence G. M. 155. Lawrence J. L. 322. Lawrence N. J. 340. Lawrie S. H. 404. Lawson D. F. 106 255. Lawson D. R. 183. Lawson T. 247. Lawton S. L. 334. Leach H. F. 213 218. Leach J. B. 268. Leard M. 301 507. Leatham M. J. 262. Leathard D. A. 181. Lebedev E. P. 304. Lebedeva N. E. 367. Le Beyec Y. 366. Le Blanc F. 136. Le Diraison M. 247. Ledoux W. A. 268. Le Duff Y. 343. Lee A. G. 293,294. Lee C. C. 376. Lee C. L. 360. Lee D. G. 109. Lee E. K . C. 189 192. Lee H. B. 479. Lee H. K. 171. Lee J. D. 322. Lee J. R. 118. Lee L. 106. Lee P. S. T. 183. Lee V. J. 244. Leffek K. T. 114 115. Lefohn A. S. 50 168. Lefort M. 366. Legasov V. A. 362. Legendre J.-J. 432. Leggett C.182. Legrand P. 346. Legzdins P. L. 389. Lehmann. H.-A. 326. Lehmkuhl H . 475. Lehn J. M. 21 255. Lehnen A. J. 358. Leibowitz L. 33. Leigh G. J. 385 413 415, Leinfelder K. 339. Leites L. A. 467. 483. Leith I. R. 218. Lekae V. A. 371. Leli R. 11. Lemarechal P. 38. Lenfant. P 249. Lenzi F. 356. Lenzi M. 126 155. Leong K. N. 507. Lepore U. 398. Lerbscher J. A, 313. Leroi G. E. 156. Le Roy D. J. 183. Leroy G. 18 19. Leroy J. F. 334. Le Roy R. J. 354. Lesaar H. 381. Lesbre M. 308. Lesigne B. 360. Leskovec R. A. 44. Lesley S. M. 279. Lestas C. N. 324. Lester G. D. 288. Lestrade J. C. 86. Letcher S. V. 27 34 36. Letelier. R. J 357. Letter J. E. jun. 41 1 502. Leuchte W. 475. Leung C. 339. Leung K. L. 31 1.Leung P. S. 85. Levchuk L. E. 361. Levenson R. A. 54. Lever A. B. P. 79 410. Leverett P. 433. Levin G. 105 120. Levina S. A. 214. Levine S. 91 93. Levison J. J. 446. Levitin 1. Ya. 445 446. Lewandos G. S. 457. Lewin A. H. 398. Lewis,E.S. 113 114 118. Lewis J. 61 62 65 66 68, 69 72 75 76 41 1 420, 428 434 460. Lewis S. R. 401 497. Leyendekkers J. V. 96. Leyland L. M. 179. Lezhnev I. B. 44. Li N. C. 121. Liberman D. 13. Liberts L. 304. Lichtenstein M. 336. Liebau F. 306. Liebmann. S. P. 21. 22. Liem B. J. 257. Lifshitz A. 181 190. Lifton J. F. 3 16. Lii R. R. 110. Liler M. 101. Lilley D. M. J. 1 1 . Lilley T. H. 91. Lim H. S. 479. Lin C.-L. 136. Lin M. C. 356. Lin Y. N. 176. Lincoln S. F. 502. Lind W. 291.Lindell W. E. 414. Lindenberg B. 485. Lindgren B. 156. Lindman B. 355. Lindner E. 252 313 320, Lindoy L. F. 414. Lindqvist O. 352. Lindsell W. E. 488 489. Lines M. E. 71. Lingafelter E. C. 66. Ling Chwang T. 254. Lingertat H. 339. Linke K.-H. 257 304. Linnett J. W. 57 136. Linsen B. G. 233. Linton M. 387. Lintvedt R. L. 399. Liorber B. G. 323. Lipp S. A. 342. Lippard S. J. 387, Lipscomb W. N. 256,259, Lischka H. 11. Lissi E. A. 177 181 273, Lister M. W. 360 500. Litovchenko L. E. 272. Litovitz T. A. 34 42 43, Little D. J. 156. Little J. L. 265. Little R. G. 444. Littler J. G. F. 135. Littler J. S. 497. Litzow M. R. 279. Liu B. 22 361. Liu C . S. 302. Livingston K. M. 351. Livington M. E. 15. Lloyd A. C. 124 355.Lloyd D. J. 382. Lloyd D. R. 278,280,282, 346,412,451,491. 266. 274. 86. 298. Lloyd J.-P. 422. Lloyd M. H. 53 292. Loader P. L. 450. Lobanov A. M. 44. Lobeeva T. S. 442. Lobikov E. A. 345. Lobkovskii E. B. 285. Lock C. J. L. 384. Lockhart J. C. 283. Loebel E. 339. Lohmar K. 296. Loehr T. M. 332 Author Index 529 Loscher J. 307. Lowdin P. O. 20 36. Logan N. 252 290 317, Lokshin B. V. 272. Lombardo E. A. 213. Long C. A. 335. Long F. A. 89 113. Long G. G. 333,473. Long G. J. 79. Long T. V. jun. 332 333, Longequeue A. M. 44. Longoni C. 447. Longuet G. 247. Longuet-Higgins H. C., Lonsdale K. 65. Loos K. 393. Lorberth J. 308 3 16. Lorenz I. P. 252 412, Lorshunov B. G. 353. Lory E. R. 262 278. Los J. M.83. Losev V. B. 304. Losi S. A. 374. Loskot S. 487. Louick D. J. 121. Louw R. 186. Lowery M. 246. Lowman D. W. 263. Lowrey A. L. 351. Lubovich A. A. 474. Luck W. A. P. 337. I ucken E. A. C. 346. Ludi A. 383. Lugli G. 477. Lukas J. 461 468. Luke M. O. 447. Lukevics E. 304. Lumb J. T. 457. Lund T. 374. Lundgren J. O. 357. Lunenok-Burmakina, Lupina M. I. 38. Lustig M. 305 326. Lutsenko I. F. 305 318, Lutz B. L. 155. Lux F. 371. Luz z. 343. Lynaugh N. 280 282. Lynd R 287. Lynde. R. A . 334. Lynton H. 358. Lyons A. R. 299 319. Lyons J. E. 435. Lyons J. R. 415. 385 41 1. 379 380. 56. V. A. 336. 323. Maas G. 103. Mabbs F. E. 62 72 76, McAlduff E. J. 191. McAllister W. A. 421. McAloon B. J. 18 90 McArdle P.490. McAvoy J. S. 268. McCabe W. 88. McCabee W. C. 337. McCartney M. E. 326. Macchia B. 325. Macchia F. 325. McClellan A. L. 91. McCleverty J. A. 422,472. McClintock M. 155. McClure G. L. 462. Maccoll A. 188. McConnell J. F. 395. McCormick C. J. 307. McCoy L. L. 120. McCreadie T. 455. McCubbin W. L. 18. McCullough D. W. 141, McCullough J. D. 358. McDaniel C. V. 205. McDevit W. F. 89. McDevitt N. T. 57. MacDiarmid A. G. 302, MacDonald C. G. 395. Macdonald D. D. 103. McDonald J. W. 392. Macdonald R. G. 336. McDonald R. S. 104. McDonald W. S. 370,479. McDowell C. A. 11. Macedo P. B. 43. McElroy M. B. 137. McEwan M. J. 127 131, McEwen G. K. 323. McFarland C. W. 3 18. McFarlane W. 3 12 382. McGarvey J. J. 119. McGee H.A, jun. 318. McGinn G. 15. McGinn J. M. 395. McGinnety J. A. 264. McGrath W. D. 141 142, McGraw G. E. 168. MacGregor R. A. 457. McGurk J. C. 130. Machin D. J. 79. MacInnes D. 378. McIntyre J. A. 358. Mackay D. J. 369. MacKellar W. J. 503. McKennon D. W. 305, 379. 155. 481. 132. 155. 326. McKenzie E. D. 78 409. Mackey D. J. 70. McKiernan J. E. 464. McKinley S. V. 310. MacKinven R. 176. McKnight C. F. 193. McKown G. L. 268. McKown M. M. 273. McLachlan A. D. 69. McLachlan V. N. 76. Maclagan R. G. A. R., McLain J. H. 235. McLaren A. B. 495. McLaughlin E. 260. McLean D. 120. McLean R. A. N. 298. McLean R. R. 406. McLean S. 188. McLeod P. E. 500. McLoughlin L. 213. McMeeking J. 407. McMeeking M. 486.Macmillan D. W. 289. McMillen D. F. 177. McMullan R. K. 350. McNesby J. R. 127 155. MacPeek D. L. 287. McPhail A. T. 72 76 322, McQuade T. J. V. 1 1 . McQuaker N. R. 265. MacQuarrie R. A. 109. McQuillan G. P. 31 1. McQuillin F. J. 446 448. McRae J. A. 369. McVay T. N. 280. McVicker G. B. 287 480. McWeeny R. 7 25. McWhinnie W. R. 55, 402 409 415. Maddock A. G. 388. Madeja K. 5 5 . Madiposky. W. M. 35 3 3 8 . Maeda T. 291. Maekawa T. 358. Magennis I. M. 322. Maggiora G. M. 23. Magill J. H. 42. Magnusson L. B. 278, Magrupov M. A. 244. Mague J. T. 453. Mahan B. H. 160. Mahanti P. 243. Maher P. K. 205. Mahmood Ali M. 239. Mailen J. C. 370. Maire J. C. 313. Maitlis P. M. 451 469, 340. 379. 337. 475 477 479 489 5 30 Author Index Majer J.R. 179. Majid A. 406. Makatun V. N. 351. Makhija R. C. 254. Maksic Z. B. 11. Malcharek F. 341. Malherbe R. 119. Malhotra K. C. 318 331, 340 342 343 344 346, 350. Malinowski E. R. 88. Malmberg M. S. 361. Malone J. F. 446. Malyesh V. I. 129. Malyutin S. A. 351. Malzahn R. 405. Mamanov T. 42. Mamantov G. 289 358. Manassero M. 400 422, Mandel N. 331. Mango F. D. 457. Mani N. V. 326. Mann B. E. 401,432,435, 436 448 449 462 467, 477. Mann C. D. M. 427,482, Mann J. B. 366. Manna A. 30. Manne R. 12 18. Mannella G. G. 136. Manners J. P. 294. Manning A. R. 482 490. Manning P. G. 338. Manning R. 193. Manoharan P. T. 488. ManojloviC- Muir L. 38 3, Mansfield W. W. 338,339. Mantovani E. 79.Manzer L. E. 440,449. Mappes G. W. 189. Marangoni G. 397 506. Marchand J. 166. Marchessault J. 39. Marciniec B. 356. Marconi W. 285 477. Marcus E. 287. Marcus R. A. 84. Marcus Y. 252. Mares F. 478. Marezio M. 368. Margerum D. W. 120, Margetts W. G. 216. Margolina E. M. 356. Margolis E. Y. 214. Margrave J. L. 305 306, 307 309 369 405. Marianelli R. S. 490. Marinov A, 366. Markham L. D. 435. 488. 441. 501. Marks T. J. 420. Marmur L. Z. 318. Marongiu G. 412. Maroni V. A. 258. Marquarding D. 324. Marquardt F. H. 120. Marre W. 43 1. Marsh R. E. 479. Marsh W. C. 326 398. Marshall A. G. 368. Marshall W. L. 96. Marsham D. F. 73,77. Marston A. L. 421. Martelli M. 397 506. Martin D. 358. Martin F. D. 44. Martin J.S. 358. Martin R. 185. Martin R. L. 61 71 73, 76 80 394 413 414. Martineau E. 251 297. Martinez N. 484. Martini G. 382. Martinot L. 372. Marty G. 232. Martynov M. S. 37. Marvich R. H. 470 Maryanoff B. E. 265. Marynick D. S. 256. Maryott A. A. 307 361. Marzilli L. G. 444. Marzilli P. A. 444. Masai H. 45 1. Masamune S. 456. Masaracchia J. 190. Maschenko A. I. 247. Maseles F. 277. MaSek J. 429. M a s h D. N. 285. Mason R. 438 446 449, Mason S. A. 295. Mason S. F. 403 404. Mason W. R. 500. Massagli A. 360 500. Massey A. G. 280 452. Massol M. 308. Masters C. 435 436 479. Mastin S. H. 334. Mastroianni M. J. 83. Mataboni R. J. 155. Mather D. S. 366. Matheson A. J. 27,41 42, Matheson T. W. 426. Mathews C. W. 168. Mathieu M.206. Matschiner H. 295. Matsumoto H. 209. Matsumura Y. 332 333. Matteson D. S. 272. Mattina M. J. 466. 485. 43,44. Matts T. C. 504. Matuschke R. 295, Matushek E. S. 283. Matyusha A. G. 323. Mawby A. H. 381. Mawby R. J. 452 471, Mayer E. 260. Mayfield H. G. jun. 402. Maylor R. 416. Mays M. J. 292 425 428, Mays R. L. 208. Mazdiyasni K. S. 289. Mazerolles P. 308. Mazhar-UI-Haque 369. Mazzei A, 285. Mazziotti A. 15. Meaburn G. M. 134. Meakin P. 479. Meany J. E. 107. Medema D. 466. Medvedev A. S. 351. Medvedev A. V. 272. Meeks E. L. 44. Mehl J. 21. Meier G. H. 236. Meier K. 339. Meier W. M. 197 199. Meira L. G. 137. Melander L. 112. Melashevich L. N. 214. Melekh B. T. 315. Melton L. A. 155. Menes F.338. Menghani G. D. 110. Menil F. 387. Mentall J. E. 127. Mentasti E. 505. Menzinger M. 362. Merbach A. 377. Mercer M. 476. Merello R. 41 1. Merer A. J. 171. Meriaudeau P. 247. Merlin J. C. 355. Merrill J. C. 193. Mersecchi R. 488. Mertschenk B. 429. Messina A. 31 5. Messing A. W. 301. Messmer R. P. 396. Mestroni G. 413,419,445, Metcalfe J. 187. Metras F. 300. Mette H. D. 168. Metz B. 255 257. Mewherter J. L. 366. Mews R. 318 349. Meyer B. 342. Meyer E. F. jun. 314. 472. 480 491. 479 A u tho r Index 53 1 Meyer H. 1 I . Meyer J. A. 155. Meyers T. C. 329. Meyer T. J. 434 474. Meyerstein D. 398 494, M’Hirsi A. 35. Miale J. N. 207. Michael J. V. 125. Michael K. W. 301. Michaeli I. 120. Michelson C. E. 315.Michl J. 281. Michl R. J. 398. Midcalf C. 486. Middaugh R. L. 266. Middlehurst J. 339. Midland M. M. 273. Mieras R. 378. Mikhailik S. K. 323. Mikhailov B. M. 272,275, Mikhailov I. G. 34. Mikhailyuchenko N. K., Mikheiken. I . D 218. 247. Mikovsky R. J. 215. Mikulski C. M. 324. Mileshkevich V. P. 305. Milewski C. A. 265. Milham P. J. 77. Milicev S. 333. Millard M. M. 310. Miller C. D. 281. Miller D. J. 28. Miller G. E. 193. Miller J. 438. Miller J. D. 415. Miller J. R. 64 420. Miller J. M. 276 396. Miller R. G. 447 451. Miller S. I. 110. Miller W. H. 22. Miller W. T. 454. Millero F. J. 89. Millier P. 21. Milligan D. E. 297 318, 343 358. Millikan R. C. 28. Mills J. L. 332. Mills 0. S. 446 463 473, Milne G.S. 123. Milne J. B. 251 297. Milstein R. 355. Milton R. M. 195. Minachev Kh. M. 195, 209 212 247. Minami K. 448. Minchev K. 21 1. Minet J. J. 356. 501. 28 1 284. 323. 477. Mingos D. M. P. 485. Minichelli D. 444. Mironov V. F. 309. Mirzabekova N. V. 209. Mishchenko K. P. 82 89. Mishin V. Ya. 363. Mishra A. K. 315. Mishra F. B. 263. Mislow K. 321. Misra B. 313. Missavage R. J. 73. Mistura L. 36. Misyuk E. T. 242. Mital R. L. 298. Mitchard L. C. 440 463, Mitchell P. C. H. 376. Mitchell R. C. 168 171. Mitchell R. W. 389. Mitchell S. J. 405. Mitra S. 75 80. Mitschke K.-H. 333. Miyahara Y. 38. Miyajima K. 90. Miyazawa T. 59. Mo Y. K. 301. Mobius K. 177. Mochalov K. N 265. Mochida I. 214. Moeller T. 350. Moiler U.319. Moers F. G. 434. Mossbauer R. L. 252,367. Mohr R. 35. Mok K. 391. Moklyak V. I. 38. Molinari E. 245. M oh-Case J. 3 92. Molnar I. 340. Molyavko L. I. 323. Monaghan J. J. 298. Moncrief J. W. 377. Monkhorst H. J. 8 19. Montague D. C. 184. Montgomery K. C. 375. Monti L. 325. Montrose C. J. 43. Mooberry E. S. 424. Mooney E. F. 354. Mooney K. R. 287. Moore C. B. 31 155. Moore C. E. 136. Moore J. 326. Moore J. W. 286. Moore M. C. 493. Moore P. 504. Moore R. E. 341. Moorhouse S. 463 481. Mootz D. 329 406. Morabito A. J. 261. Morallee K. G. 294. Moras D. 255 257. 477. Morawetz H. 494. Moreau J. J. E. 308. Moreland C. G. 277 33 1. Morell A, 315. More O’Ferrall R. A. 102, Moretto H. 306. Morf W. E. 83.Morgan C. E. 91. Morgan G . L. 256. Morgan L. O. 391. Morgan T. F. 168. Morgan T. R. 203. Mori Y. 155 336. Moriarty R. M. 121. Moriarty T. C. 255. Morita Y. 209. Moritani I. 451. Morley C. 155. Morokuma K. 18 19 22, Morooka Y. 249. Morosi G. 18. Morosin B. 66 256. Moroz E. M. 315. Morozov I. I. 356. Morozova R. P. 499. Morris A. 140 165 335, Morris B. S. 77. Morris D. G. 325. Morris D. M. 375. Morris E. D. 156 166, Morris E. D. jun. 179. Morris H. 37. Morris J. H. 283 373. Morris M. D. 333. Morris P. J. 507. Morrison J. M. 488. Morrison R. J. 436 Morrison S. R. 226 240. Morrow B. 156. Morrow B. A. 279. Morrow C. J. 488. Morse F. A. 136. Morse R. D. 171. Mortimer C. T. 467. Mortimer G. A. 458. Morton M. J.356. Moscou L. 206. Moseley K. 451 489. Moser G. A. 439. Moser H. C. 131. Mosesman M. 338. Moskowitz J. 21. Moskowitz J. W. 21 22, Moslehi H. 21 1. Moss K. C. 376 380. Moss R. L. 243 244. Motoo Shiro. 376. 115. 336. 385. 180. 24 91 362 5 32 Moulton M. C. 358. Mountain R. D. 34 35. Mowat W. 443,465,491. Moyes D. A. 315. Moynihan C. T. 42. Mu-Chang Shieh 342. Miiller A. 324 380. Miiller B. 397. Mueller D. 219. Mueller H. 356. Muller H. 275 347 468. Muller J. 281 331 422, 429 43 1 439 476 487. Mueller M. H. 372. Muller U. 296. Miiller W. 254. Muetterties E. L. 266, 479 480 488. Mugnoli A. 74. Muir K. W. 326 383 441, Muir M. M. 506. Muir W. R. 458. Mukherjee N. 25. Mukherjee R. 121. Mukherjee S. K. 498.Mukhopadhyay P. 30. Mulazzani Q. G. 501. Mulkay P. 214. Mulliken R. S. 12 24. Mullins F. P. 313. Multani R. K. 469 478. Mumme W. G. 316 375. Munakata H. 479. Munkelwitz H. E. 338. Murahashi S. 461. Muratova A. A. 315. Murdoch J. D. 307. Murgia S. M. 429. Murmann R. K. 497 503. Murphy C. B. 279. Murphy W. F. 357. Murray J. D. 312. Murray K. S. 76 78. Murray R. K. jun. 321. Murray R. S. 388 499. Murrell J. N. 163 176. Murrill E. 106. Murthy A. S. N. 336. Murthy M. K. 309. Murty D. S. 388. Musco A. 459. Musgrave W. K. R. 11. Musgrove H. H. 497. Mushkin Y. I. 311. Mushran S. P. 388. Musina A. A. 315. Musso H. 55 252 41 1. Muthusubramanian P., Muto M. 412. Muto Y. 74. 481. 359. Muzykantov V. S. 247. Myatt J. 443 470.Myers G. H. 164. Myers V. G. 392. Myerson A. L. 126. Naccache C. 206 215, 218 247 335. Nachbaur E. 296. Nagakura S. 396. Nagao S. 284. Nagel A. 340. Nagy G. A. 361. Naik D. V. 31 1. Naito S. 248. Nakagawa I. 59. Nakagawa K. 448. Nakahara M. 379. Nakamoto K. 55 56,255, 380 393 487. Nakamura A. 321 448. 464,466. Nakamura Y. 41 1. Nakanishi K. 357. Nakano T. 293. Nakatsuji H. 1 1 . Nakayama S. 324. Nalbandyan A. B. 356. Naldini L. 400 488. Nancollas G. H. 92 252, Napier,I. M. 168 171 315. Naqvi R. R. 329. Narasimham A. V. 34. Nardelli M. 351. Nardini G. 444. Naruyana D. 239. Nasielski J. 421. Nassiff P. J. 68. Nassimbeni L. R. 430. Nasta M. A. 481. Natile G. 377 424. Naugle D. G. 33 34. Naumov V. A.322. Nave C. 255. Nayer V. U. 356. Nechvatal A. 182. Neese H.-J. 406 481. Nefedov V. D. 361. Negishi E. 261. Negita H. 116. Negoiu D. 401. Negrebetsky V. V. 277. Neikam W. C. 218. Nekaeva I. M. 483. Nelson D. P. 255. Nelson G. L. 188. 367. Author Index Nelson J. 341. Nelson J. H. 459. Nelson R. P. 44. Nelson S. M. 61 78 412, Nelson Wright A. 136. Nemeth E. M. 192. Nemiroff M. 282. Nemzer I. I. 500. Nesmeyanov A. N. 424. Neuman D. 21. Neumann F. 294. Neumann W. P. 302. Neville A. F. 273. Newing C. W. 406. Newlands M. J. 313 461, Newman R. H. 132. Newton D. C. 52 53 57. Newton G. W. A. 366. Newton M. D. 22. Newton T. W. 495. Nicholas K. 425. Nichols A. L. 369. Nichols W. H. 32. Nicholson J. K. 446. Nickerson R.F. 278. Nicklin H. G. 316. Niclause M. 185. Nicolaon G. A. 232. Nicolet M. 336. Niecke E. 328. Niedenzu K. 283. Niederreuther U. 43 1 . Niemeyer H. N. 109. Nifant’ev E. E. 320. Niinisto L. 341. Niki H. 164 179 180. Nikitin E. E. 154. Nikitin I. V. 354. Nikolov G. S. 351. Nilsson J. L. G. 119. Nisel’son L. A. 353. Nishii N. 333. Nishikawa S. 38 121. Nishimura J. 301. Nixon E. R. 336. Nixon J. F. 326 408 486. Niyazov S. 34. Ng C. F 73. Nguyen-H uy-Dung 368. Nobile C. F. 483. Noble A. M. 382. Noble P. M. 358. Noel S. 346. Nolle D. 284. Noth H. 273 277 279, 466. 487 489. 284 312 464 480. Noftle R. E. 349. Nolte C. R. 434. Noltes J. G. 308 309. Nomoto O. 35 85 Author Index 533 Nomura H. 38. Nomura T. 379.Norbury A. H. 317,412. Norden B. 404. Nordling C. 459. Nordmeyer F. R. 494. Norman A. D. 263 265, Norman J . G 389 392. Norman R. 0. C. 340. Norris A. R. 110 11 1. Norris C. 494. Norris T. H. 343. Norrish R. G. W. 130, 135 155 156 168 171. Norseev Yu. V. 361. Norstrom R. J. 171. North A. M. 37. North B. 475. North P. P. 310 314. Northey H. L. 337. Norton R. B. 137. Novak J. 498. Nowicka-Jankowska T., Nowotny H. 284 309. Nowotny J. 221 222 223, Noxon J. F. 136 142. Noyes R. M. 358 500. Nozakura S. 461. Nozdrev V. F. 35 37. Nudelman A. 104. Nugent L. J. 370 469. Nunokawa H. 121. Nurmia M. 365. Nuttall R. H. 401. Nyburg S. C. 313 398. Nyholm (Sir) R. S. 403, 299 3 12. 252. 225. 426 448 449. Oakley R. T. 326.Oberhammer. H 349. O’Brian R. J. 164. O’Brien C. 1 16. O’Brien D. E. 154. O’Brien R. J. 286 427, O’Brien W. D. 40. O’Brien W. J. 339. Ochiai E. 412. O’Connor C. J. 110. O’Connor M. F. 400. O’Connor M. J. 252. Oda Y. 345. O’Deen L. A. 183. O’Dell. M. S. 185. Odenthal R.-H. 400. 442 482. Odom J. D. 263,279. O’Donnell D. 119. O’Donnell T. A. 384,404. Odum R. A. 192. O’Dwyer M. F. 11. Ohrn Y. 15. Oelkrug D. 406. Osterberg O. 39. Ofele K 439. O’Ferral R. A. M. 91. Ogawa K. 423. Ogawa M. 155. Ogawa T. 173. Ogden J. S. 314 421. Ogilvie J. F. 171 461. Ogren P. J. 395. Ogrin T. 362. O’Hare P. A. G. 22 166, Ohashi K. 494. Ohashi Y. 396. Ohtaki H. 97. Ohtsuki T. 494. Okabe H. 144 155 335. Okabe T. 342. Okamoto Y.217. Okano M. 293. Okawara R. 291,294,332, Okazaki R. 324. O’Keefe M. 241. Okhlobystin 0. Yu. 272. Okinoshima H. 300 482. Okubo T. 356. Okumiya M. 289. Olah G. A. 116 301 318, Oldershaw G. A. 155 156, Oldfield D. 31 1 . Oldman R. J. 133 135, O’Leary B. 10. Olechowski J. R. 437. Olive S. 376 419 506. Oliver A. J. 476. Oliver B. G. 91. Oliver J. D. 486. Oliver J. G. 289 291. Oliver J. P 286. Ollis C. R. 390. Olsen B. A. 341. Olsen F. P. 341. Olsen R. R. 268. Olson D. C. 393 397. Olson D. H. 197 198,215. Olsson E. 459. Omura H. 459. Onada T. 436. Onak T. 268. O’Neal H. E. 175 177, 359. 333. 461. 352. 138. 185 186 187 189. O’Neil S. V. 22. Ong T. E. 260. Onishi T. 248. Ono S. 289. Ono Y. 203. Onoue H.448. Onsager L. 94. Ooi S. 41 1. Oommen T. V. 342. Oosterhout G. W. 228. Opie M. C. 116. Opperman M. 261. Oppermann H. 382. Orchard D. G. 422. Oref I. 176. O’Reilly D. E. 90. Orenberg J. B. 333. Orio A. A. 479. Orioli P. L. 391. Orlova L. V. 272. Ormondroyd S. 88. Ornstein M. H. 128. Orville-Thomas W. J. 36, Osaki K. 282. Osborn C. L. 190. Osborn J. A. 460 480, Osborn R. S. 314. Osborne D. T. 125. Osborne D. W. 359. Osborne M. J. 147. Osburn C. M. 234 235. O’Shea S. 19. Osiecki J. H. 378. Osinga T. J. 233. Ossa E. 190. Ostrovskii. V. E 235. Otouma H. 203. Otsuka A 90. Otsuka K. 168. Otsuka O. 475. Otsuka S. 321 408 423, 448 464 466 486. Ott J. B. 253. Ottinger Ch. 155 159. Ottley R. P. 279. Ouellette T.J. 3 17. Ouillon R. 343. Overbeek J. T. G. 339. Overend W. R. 41 5. Owen B. B. 98. Owen D. A, 272,273,455. Owen J. 63. Owen J. D. 264. Owens C. 3 15. Owens F. J. 356. Owens P. H. 109. Owston P. G. 255. Oyama N. 121. Ozaki A. 247 248 249. Ozbirn W. P. 320. 37. 484 534 Author Index Ozias Y. 340. Ozin G. A. 49 52 252, 286 351 352 363. Pace E. L. 357. Packer K. J. 103. Paddock N. L. 326 328. Padmini A. R. K. L. 36. Padwa A. 190. Patzmann H. 326. Paetzold P. I. 273. Paiaro G. 459. Paige H. L. 277. Pajares J. A. 245. Pakhomov V. I. 272. Palazzi A. 485. Palenik G. J. 399. Paliani G. 429. Palino G. F. 192. Palmer J. M. 410 505. Palmieri P. 7 340. Palumbo R. 459. Panattoni C. 3 13 Panckhurst M. H. 93. Paniago E.B. 501. Pankowski M. 452. Pannetier G. 156. Panov G. I. 247. Pantaleo D. C. 377. Pantini G. 465. Paphitis A. C. 28. Papic M. M. 182. Paquette L. A. 455 456, Pardoe G. W. F. 337. Parfitt G. D. 249. Paris R. A. 284. Park J. 473. Parker G. 464. Parker J. 254. Parker J. H. 150. Parker L. M. 286. Parker R. M. 187. Parkes D. A. 140. Parkes D. D. 136. Parks N. J. 193. Parks-Smith D. G. 29. Parpiev K. 32 37 42. Parravano G. 229. Parris G. E. 257. Parrott J. C. 290. Parry R. W. 264,319,330, Parshall G. W. 47 1 488. Pascal J. L. 360. Pashinkin A. S. 351. Pasinski J. P. 318. Passmore J. 340 345 358. Pasternack R. F. 503. 457. 419. Pasynkiewicz S. 287. Pasynskii A. A. 470. Patel C. C. 394. Patel K. C. 78 377. Patmore D.J. 487. Pattengill M. D. 192. Patterson D. B. 285. Pattison S. 121. Paukert T. T 168. Paul I. C. 73 350. Paul K. K. 331 346. Paul R. C. 318 331 340, 342 343 344 346 350, 371. Pauling L. 80. Paulus E. F. 353. Pauly H. 40. Pauncz R. 20. Pauson P. L. 427 446, 473 486. Pavia A. 360. Pavlath A. E. 358. Pavlou S. P. 176. Pavlycheva A. V. 3 11. Pawson D. 392. Paxson T. E. 261 272, Payne D. A. 249. Payne M. A. 106. Peach M. E. 316. Peacock R. D. 354 368, Peacock S. J. 186. Peak S. 290 502. Peake S. C. 325. Pearce C. 179. Pearson P. S. 352 353. Pearson R. G. 101 392, 458 488 503. Peart B. J. 404. Pebler J. 41 1. Pechkovskii V. V. 351. Pedersen L. 336, Pedley J. B. 276 279 302. Pedone C. 267. Pedrotti U. 477.Peel T. E. 109. Peerdeman A. F. 320. Pelliger G. 419. Peloso A. 495. Pelter A. 261 275. Penchev V. 21 1. Pendygraft G. W. 1 15. Penfold B. R. 426 454. Penland A. D. 290. Pennella F. 478. Penneman R. A. 366 369. Penney G. J. 330. Penrose D. J. B. 379. Penzes S. 132. Penzhorn R. D. 357. Peone J. jun. 436 489. 507. 380 397. Perchard J. P. 357. Perepechko 1. I. 44. Pergola F. 360. Pergola K. 500. Perkins I. 453. Perkins P. G. 11 18 90, 278 283 373 467. Perlman M. L. 366. Perlmutter-Hayman B., Perlstein J. H. 242. Perner D. 134. Perona M. J. 189. Perram J. W. 91. Perrot M. 357. Peruzzo V. 313. Peschel G. 339. Pesek J. J. 506. Peshev O. 244 248. Petcher J. J. 370. Peter J. 366. Peters M. J. 179. Peters R. D.44. Petersen R. B. 287 473. Petersen S. 339. Peterson E. M. 90. Peterson J. R. 370. Peterson L. K. 276 322. Peterson N. C. 126 342. Peterson S. W. 362. Pethica B. A. 338. Pethrick R. A. 37. Pethybridge A. D. 81 95. Petrosyants S. P. 315. Petrov E. S. 352. Petrovich J. P. 461. Petrovskii P. V. 424. Petrucci S. 39 42 85 97. Pettit L. D. 252. Pettit R. 425 455 457, Petukhov G. G. 275. Peverill K. I. 76. Peyerimhoff S. D. 22. Peyron M. 357. Pez G. P. 350. Pezdic J. 345. Pfaifer Z. 467. Pfohl S. 324. Pham-Van-Huong 357. Phavanantha P. 77. Phillips C. 488. Phillips D. J. 78 377. Phillips G. G. 68. Phillips L. F. 10 127 131, Phillips R. F. 441. Phillips R. K. 396. Phillips T. T. 192. Philoche-Levisalles M., Phipps D.A. 501. 111. 468. 132. 258 Author Index 535 Picard J. P. 301. Pickel H. H. 304. Pickert P. E. 208 210. Pickett R. C. 129. Pierpont C. G. 381 390, Pietropaolo R. 419 467, Piguzova L. I. 204. Pihl H. 277. Pikal M. J. 94. Pike W. T. 338. Pilbrow J. R. 374. Pilbrow M. E. 449. Pilipovich D. 358 360. Pilling M. J. 147 155 168, Pilot J. F. 324. Pimentel G. C. 50 91, 150 168 171 173 317, 356 358. Pince R. 421. Pincelli U. 340. Pinchas S. 56. Pine A. S. 32. Pings C. J. 36. Pink R. C. 213 346. Pinkerton A. A. 324. Pinnavaia T. J. 289 382. Pinnow D. A. 43. Pioli A. J. P. 442. Piovesana O. 376. Pitaevskaya L. L. 3 1. Pitman I. N. 107. Pitre J. 132. Pitt M. 245. Pitts E. 95. Pitts J. N. 130 165. Pitzer K. S . 98.Pladziewicz J. R. 495. Planck C. J. 202. Plass K. G. 38. Plato V. 265. Platt A. E. 181. Platt R. H. 491. Plattner G. 313. Plazek D. J. 42. Planogna G. 313. Plekhov V. P. 315. Plesek. J. 265. Pleskov W. A. 83. Plichta P. 299 307. Plurien P. 360. Pocker Y. 107 110. Podlaha J. 383. Podrick T. D. 356. Pohl S. 309. Poilblanc R. 421 435. Poise] H. 341. Polanyi J. C. 149 191, 484. 468. 183. 192 336. Poletti A. 429. Poliakoff M. 421. Policec S. 408. Polikarpova M. A. 377. Politzer P. 24. Pollack M. E. 337. Polotebnova N. A. 499. Polovnyak V. K. 265. Polston. W. C. 261. Polyachenok 0. G. 351. Ponsionen R. 352. Pope B. M. 187. Pope M. T. 399,497. Pople J. A. 9 10 18 22, 336 357. Popov A. I. 359 408. Popp G. 271.Poppe W. 155. Poon C. K. 391 504. Poore M. C. 334. Porcham W. 354. Porri L. 465 466. Porta P. 376. Porter E. J. 332. Porter G. 171. Porter J. K. 72. Porter R. F. 155 260,262, Portier J. 31 5 . Potapova G. F. 336 344. Potapova T. V. 272. Potier A. 290 360. Potoratskii G. M. 82. Pottel R. 86. Potts A. W. 355. Potts D. 308. Poublan J. 247. Pouchard M. 254 378. Poutsma M. L. 195. Powell H. K. J. 504. Powell H. M. 482 490. Powell J. 446 466. Powell K. G. 446 448. Powell M. J. D. 25. Powell P. 282. Powell R. L. 329. Powell W. B. 340. Pozett R. W. 260. Pozzo A. 338. Prados R. A. 388 389. Prangsma G. J. 30. Prasad H. S. 315. Prasad R. 35. Prater C. D. 245. Pratt C. S. 484. Pratt G. L. 176 184. Pratt G. W. 221.Pratt J. M. 452 457. Praud L. 21. Preer J. R. 394. Pregaglia G. F. 435. Preiss H. 331 332 333. 278 282. Prest M. L. 214. Preuss H.-W. 22. Previtali C. 177. Prewett C. T. 396. PribaniC M. 424. Piibil R. jun. 429. Price K. A. 74. Price M. G. 504. Price R. 487. Price S. J. W. 177 185, Price W. C. 355. Prince D. J. 350. Prins R. 474. Pritchard G. O. 177 189. Prokof’eva E. N. 204. Prons V. N. 328. Proskurnina M. V. 318, Prout C. K. 322 326 382, Prue J. E. 81 84 89 92, Prusakov V. N. 361 362. Pryor W. A. 113. Pscheidl H. 244. Pszonka H. 287. Pu L. S. 483. Puar M. S. 105. Pucci A. 484. Puchelt H. 345. Puchkov V. V. 337. Puddephatt R. J. 449. Pudjaatmaka A. H. 109. Pudovik A. N. 315. Puentes M. J. 185. Pulham R. J.253 254. Pupp M. 424. Puppe L. 415. Puri J. K. 318 331 340, Purnell J. H. 181 184. Purser J. M. 259. Puskaric E. 346. Puxeddu A. 413,419,444. Pytlewski L. L. 315 324. 186. 323. 490 49 1. 94 95 376. 346. Quail J. W. 387. Quane D. 302 504. Quarta A. 469. Quaterman L. A. 359. Quattrochi A. 393. Quentin J. P. 347. Quested P. N. 66 68 69. Quick L. M. 181. Quid L. D. 322. Quinn H. W. 461. Qureshi A. M. 346 361 536 Author Index Rabe B. R. 168. Rabenau A. 352. Rabet F. 303. Rabinovitch B. S. 175, 176 177 179 184 191. Rabo J. A. 195 208. Racanelli P. 465. Radeck D. 329. Radom L. 22. Radonovich L. J. 368. Raff L. M. 30. Ragsdale R. O. 279 315. Rahlin M. Ya. 381. Rahman A. 337. Rai G. 34. Rainey K. C. 121. Rajagopalan S.33. Rakov A. A, 336 344. Ralph E. K. 103. Ramakrishna R. S. 294. Ramanathan P. S. 96. Ramaswamy A. V. 242. Ramaswamy K. 392 359. Ramirez F. 324. Ramsay D. A. 168 171. Ramunni G. 11. Randaccio L. 444. Randall E. W. 422. Randall G. L. P. 452. Randall R. S. 313. Ranganathan T. N. 328. Rangarajan S. K. 97. Rankin D. W. H. 307,317, Ranney S. J. 379. Rao C. N. R. 336. Rao K. V. S. 355. Rao M. G. S. 33. Rao T. N. 168. Rao V. V. K. 324. Raper G. 479. Rapp D. 29. Rapp R. A. 236. Raseev G. 218. Rasing J. 35 39. Ratajczak E. 124 175. Ratcliffe C. T. 297. Rath N. S. 337. Ratnasamy F. 242. Ratov A. N. 21 1. Rau H. 352. Rausch M. D. 439 442. Ravez J. 405. Rawlinson S. R. M. 420. Ray J. 257. Raymond J. I. 166 340, Raymond K.N. 394,45 1, Rayner-Canham G. W., Raynor. J. B. 383. 325 430. 359. 478. 486. Raziere J. 290. Razumov A. I. 323. Razumovskii V. V. 461. Razuvaev G. A. 333. Read A. J. 84. Read A. W. 30. Read F. H. 161. Reade W. 27;. Reardon J. D. 179. Reddy A. N. 81. Redhouse A. D. 489. Redington R. L. 358. Reed C. A. 488,489. Reeder R. R. 376. Reedijk J. 408. Reeke G. N. 310. Rees G. V. 490 491. Rees L. V. C. 198. Rees R. 191. Rees R. G. 323. Reeves C. M. 25. Reeves L. W. 11. Regnet W. 277. Rehder-Stirnweiss W., Reich C. 468. Reichenbach G. 429. Reifsneider S. B. 27. Reikhsfel’d V. O. 304. Reilly P. J. 96 98. Reimann G. W. 408. Reimann R. H. 430. Reimer K. J. 380. Reinhardt G. W. 168. Reis A . H. jun. 271 282, Reisenhofer E.419 444. Remeika J. P. 368. Remmer G. 326. Rempel G. I. 412. Rempel G. L. 389. Rendall I. F. 407. Renk 1. W. 423 487. Renoe B. W. 462. Rentzepis P. M. 173. Reuveni A. 343. Reynard L. 340. Reynolds D. J. 15 268, Reynolds W. L. 346. Rheault F. 44. Rhine W. 253. Rhyne T. C. 345. Ricci J. S. 450. Rice D. A. 373 380 441. Rice D. P. 460. Ricevuto V. 449. Rich L. D. 120 505. Richelson M. R. 42. Richey W. M. 245. Richard J. P. 185. Richard Y. 313. 436. 385. 351. Richards A, 76 379. Richards L. W. 168. Richards P. L. 385. Richards R. E. 89. Richards R. L. 367 438, Richards W. G. 21. Richardson A. E. 193. Richardson F. S. 403. Richardson J. T. 203,215. Richardson W. H. 177, Rickard C. E. F. 371 375.Rickborn B. 262. Ricroche M.-N. 445. Riddle C. 307. Ridley D. R. 313 332. Riebling R. W. 340. Rieck R. 414. Rieder K. 383. Rieger P. H. 376. Riekens R. 300. Rienitz H. 329. Riesel L. 326. Rieter P. C. U. 350. Rietz G. 307. Rietz R. R. 269. Riley E. M. 477. Ring D. F. 184. Ring M. A. 185 299 300. Rinze P. V. 464. Ripoll M. M. 278. Rippen D. M. 405. Ritson D. M. 97 262. Ritter G. 412. Ritter J. J. 279. Rix C. J. 43 1. Robb J. C. 179 286. Roberts P. B. 40 182,273, Roberts G. G. 463 472. Roberts N. K. 337. Roberts P. J. 434. Robertson G. B. 443,444, Robertson I. C. 467. Robiette A. G. 306 317, Robinson B. H. 119 426, Robinson E. A. 109 351. Robinson K. 155 156, Robinson P. J. 306. Robinson P. W. 420. Robinson R.A. 96 98. Robinson S. D. 446 448, Robinson V. J. 366. Robinson W. R. 292,480. Robinson W. T. 485. Robson H. E. 207. 440. 189. 274. 449 462. 359. 478. 352. 487 Author Index 537 Roby K. R. 7 9 10. Rocek J. 498. Rochester C. H. 101 11 1. Rockstroh C. 319. Rodenburg W. W. 356. Rodgers A. S. 177. Rodgers J. 261 322. Rodina 1. A. 248 249. Rodionov A. N. 287. Rodriguez J. A. 349. Roe D. M. 475. Roesky H. W. 311 317, 325 326 328 347 349. Rogers D. 77 314. Rogers D. B. 396. Rogers M. T. 361. Roginskaya T. N. 296. Roginskii S. Z. 217 245. Rogl P. 284. Rohbock K. 41 5. Rohrbaugh W. L. 386. Roitman J. N. 117. Rolfe N. 380. Romanov V. P. 35. Romeijn F. C. 228. Romeo G. 84. Romeo R. 449. Romm R. 104. Rona P.277. Roos B. 2 1 340. Root J. W. 192 193. Root K. D. J. 383. Roothaan C. C. J. 25. Roper W. R. 438 488, Rorabacher D. B. 503. Ros R. 343 414. Rose M. C. 107. Rose P. D. 422. Rosenbaum E. E. 101. Rosenbaum I. J. 33. Rosenberg E. 422. Rosenblum M. 475. Rosenstein G. 352. Rosenthal R. I. 165. Rosmus P. 11 12. Rosolovskaya E. N. 203. Rosolovskii V. Y. 257, Ross D. S. 178 311 340. Ross E. P. 423 481. Ross I. G. 72. Ross K. J. 140 165 335, Rosseinsky D. R. 83 93, Rosser R. W. 374. Rossi M. 478 483 484. Rossknecht H. 318. Rossotti F. J. C. 92. Rossotti H. S. 92 102, 489. 330 354. 342. 96 97 449. 339. Roth W. R. 188. Rothgery E. F. 276. Rothwell H. L. 29. Rouchaud J. 214. Roundhill D. M. 292,462, Rourke F. M.366. Rouschias G. 440. Rousseau D. L. 338. Rouxel J. 256. Rowland F. S. 183 184, Rowley J. K. 93. Rowlinson J. S. 33. Roy R. S. 149. Royston L. K. 72. Rozenberg L. D. 27. Rozenthal D. K. 93. Rubenstein P. A. 109. Rubezhov A. Z. 467. Rucci G. 425. Rucklidge J. C. 442. Rudd D. P. 499. Ruddick J. D. 389,441. Rudler H. 483. Ruedenberg K. 12. Rudorff W. 294. Ruegg M. 383. Ruepell H. 505. Ruff E. L. 104. Ruff I. 496. Ruff J. K. 325 422 428, 432 45 1. Rugheimer J. H. 280. Rumfeldt R. C. 345. Rumin R. 188. Ruppel H. 120. Rush J. J. 318. Rush R. M. 97. Rusholme G. A. 485. Russell D. R. 334 444, 446 449 454 460. Russell G. A. 106 255. Russell J. 257. Russell R. L. 183. Rustembekov K. G. 351. Rutherford D. 105. Rutherford J.S. 326. Ruttinck P. J. A. 12. Ryan F. J. 331. Ryan J. L. 370 371. Ryan R. R. 334 369. Ryang M. 491. Rybin L. V. 424. Rybinskaya M. I. 424. Ryder G. A. 78. Rydh R. 155. Rynbrandt J. N. 175 191. Ryschkewitsch G. E. 262. Ryser A. P. 500. Rytting J. H. 255. 480. 192 193. Sabels B. R. 345. Sabin J. R. 342. Sacco A. 478 483 484. Sachs W. H. 102 11 1. Sachtler W. M. H. 249. Sadri G. 330. Sadykhova S. K. 40. Safari H. 349. Safarik I. 181. Safafik. L. 254. Safford G. J. 85. Safonov V. V. 353. Sagatys D. S. 106. Sage M. L. 70. Sahl K. 316. Sahm K. F. 28. Sahuri S. 328. Saillant R. B. 428. Saini G. 505. Saito H. 284. Saito S. 342. Saito T. 257 479. Saji Y. 32. Sakai M. 456. Sakai S. 482. Sakakibara M.4d2. ' Sakakibara T. 288. Sakamoto Y. 496, Sakk Z. G. 257. Sakurai K. 156. Salahub D. R. 11. Salama A. 343. Salama S. B. 343. Sala-Pala J. 376. Salem L. 22 186. Sales K. D. 406. Salewski R. 295 316. Salmon J. E. 409. Salomaa. P. 115. Salomon M 84 181. Salomon M. F. 458. Salzmann J. J. 64. Samplavskaya K. K. 35 1. Sams J. R. 313 429 481, Samuel E. 474. Sancier K. M. 240. Sand L. B. 204. Sanders D. A. 286. Sanders J. R. 471. Sanders J. V. 233 234. Sandhu H . S. 132 181, Sandhu S. S. 402. Sandorfy C. 11. Sandoval H. L. 357. Sandyman D. J. 308. Sanger A. R. 490. Sanhueza E. 171,274. Sannikov A. P. 119. San Roman E. A. 359. 487. 190 191 538 Author Index Sansoni M. 400 488. Santo W. 442. Santry D. P. 9 1 1 19.Sanz F. 320 443. Saran A. 1 I . Saran H. 349. Sarapu A. C. 420. Sardle W. J. 133. Sarel S. 468. Sarkisov 0. M. 356. Sarneski J. E. 404. Sartori P. 358. Sas T. M. 367. Sasaki K. 337. Sasaki Y. 341 491. Sastry G. S. 36. Satge J. 308. Sato M. 218 331. Satterfield C. N. 216. Sattlegger H. 254. Sauer M. C. V. 339. Saumagne P. 337. Saunders J. E. 279. Saunders V. R. 21 260, 330 340 420. Sauvage J. P. 255. Saverly J. D. 288. Savory C. G. 263 268. Saxena J. P. 110. Scaiano J. C. 18 1 274. Scaife D. E. 402. Scandola F. 474. Scantlin W. M. 263 299. Scaramuzza L. 376. Scarborough J. 86. Scatchard G. 97. Schaaffs W. 33. Schachtschneider J. H., Schack C. J. 360. Schafer H. 252 254 367, Schaefer H. F. 22 183, Schafer L.58 477. Schafer W. 441. Schaeffer C. D. jun. 298. Schaeffer R. 269 277. Schaper B. J. 289. Schastlivyi V. P. 350. Schaumburg K. 11. Schder F. R. 425. Schechner P. 190. Scheer M. D. 131. Scheffler K. 308. Schegolev V. A. 365. Scheidt W. R. 375. Schenck R. 298. Schenk A 353. Scherer 0. J. 303 304* 323. Scherr P. A. 286. 457. 378 381. 361. Scherzer J. 198 205. Scheuermann W. 265. Schiff H. I. 142 336. Schipperijn A. J. 461. Schiwy W. 309. Schlemper E. O. 315. Schlesinger G. 366. Schleyer P. von R. 10 1 1 5. Schlientz W. J. 451. Schlosser M. 321. Schmeissner F. 33. Schmid G. 480. Schmid G. H. 104. Schmid H. 188. Schmid J. 33. Schmidbaur H. 252 288, 303 304 333 348 441, 450 488. Schmidpeter A. 318 323, 328. Schmidt A.326 333. Schmidt M. 319 341. Schmidt P. 306. Schmidt U. 341. Schmidt W. 334 494. Schmidtke H. H. 64. Schmiedel H. 219. Schmithals F. 86. Schmitz-DuMont O. 303. Schmulbach C. D. 252, 292 328. Schmutzler R. 324 325, 327 329 332,430. Schneer-Erdey A. 362. Schneider M. E. 112. Schneider R. J. J. 470. Schnell E. 258. Schnitzler M. 431. Schodl G. 443. Schoeller W. 186. Schofield K. 124. Scholer F. R. 265. Schomaker V. 208. Schorpp K. 437,487. Schott G. 305. Schotter R. 28. Schram E. P. 283. Schrauzer G. N . 366,445, Schreiber G. 399. Schreiner F. 359. Schrieke R . R. 287 473. Schrobilgen G. J. 362. Schrock R. R. 460. Schroder H. H. J. 319. Schroeder L. W. 318. Schrodter K. 257. Schroter D. 326. Schrotter H.W. 405. Schuetzle D. 176. Schuierer E. 422. 479. Schulman J. M. 24. Schultz A. J. 413. Schultz R. J. 408. Schulze M. 306. Schumacher H. J. 346, Schumann H. 305,431. Schurath U. 161. Schurig V. 460. Schussler D. P. 292 480. Schuster P. 11 22. Schuster R. E. 290 372, Schutte C. J. H. 265. Schwab G.-M. 235. Schwabe K. 90. Schwalbe C. H. 266. Schwan H. P. 40. Schwartz K. 14. Schwartz L. D. 261. Schwartz R. D. 256. Schwartz S. E. 168. Schwarzenbach G. 92. Schwarzer J. 475. Schwarzhans K. E. 367. Schwarzl F. R. 42. Schweig A. 11. Schweighardt F. K. 12 1. Schweitzer P. 358 500. Schwerdtfeger C. F. 72. Scordamaglia R. 442. Scott A. 402. Scott B. F. 338. Scott J. M. 467. Scovell W. M. 450. Scroggie J. G. 375. Searles S.K. 86. Sears C. T. 451. Secco F. 344 500. Seel F. 319 340 344. Sefcik M. D. 300. Segal E. 245. Segal G . A. 9 18. Segal J. A. 432. Segre A. 489. Seibold C. D. 483. Seifert B. 295. Seifert W. 368. Seifullina I. I. 309. Seip H. M. 11 443. Seip R. 443. Seitter H. 344. Seiyama T. 214. Selander H. 119. Seleznev V. A. 217. Selig H. 359 361 384. Selke A. 360. Selte K. 343. Semashko V. N. 322. Semenenko K. N. 285. Sen B. 291. 359. 502 Author Index 539 Senges S. 325. Senghaphan W. 33. Senior B. J. 48 1. Senior J. B. 358. Senoff C. V. 397. Senor L. E. 265. Sentek A. E. 374. Seppelt K. 304 349 407. Serafini A. 330. Seregin P. P. 315. Serpone N. 313. Serre J. 21. Sessa P. A. 318. Setaka M. 240. Setser,D.W. 124 155 184, Sette D. 32 35. Seyferth D. 301 426 462. Shagova E. A. 272. Shah B. 506. Shahid M. S. 341. Shakhashiri B. Z. 378, Shakhnazaryan A. A. 294. Shalayevsky M. R. 365. Shamsuzzoha M. 198. Shannon J. S. 395. Shannon R. D. 396. Shannon T. W. 298. Shapiro J. 127. Shapiro S. A. 110. Shapley J. R. 460. Sharma B. D. 346. Sharma D. N. 356. Sharma K. K. 31 1 . Sharma K. M. 478. Sharma R. D. 160 331. Sharp D. W. A. 323 325, 326 338 340 352 354, 358 406. 191 297. 496. Sharp K. G. 305 306. Sharrocks D. N. 282. Sharts C. M. 187. Shatenshtein A. I. 119. Shavandin Yu. A. 204. Shaver A. 328. Shaw B. L. 435 436 440, 446 448 449 450 457, 460 462 467 479. Shaw C. F. 302. Shaw G. 428,467. Shaw K. N. 11. Shaw M. J. 362.Shaw R. 178. Shaw R. A. 321 322 326, Shchekochikhim U. M., Shcherbakov V. I. 290, Shea C. 493. Shearer H. M. 288. Shears B. 506. 328. 247. Sheena H. H. 168. Sheldrick G. M. 302 306, 317 330 332. Sheline R. K. 423 424. Sheluchenko V. V. 319. Shenkin P. S. 474. Shenoda F. B. 33. Shepp A, 177. Sheppard N. 338. Sheppard W. A. 296,459. Sherle A. I. 252 410. Sherry H. S. 198. Sherwood P. J. 282. Sherwood P. M. A. 295, Sherwood R. C. 76 394. Shestakova N. A. 315. Shevelev S. A. 252. Sheverdina N. I. 287. Sheyanov N. G. 316. Shibaeva R. P. 308. Shields F. D. 28 44. Shields L. 406. Shigehara Y. 247. Shilov A. 366. Shilov A. E. 408 483. Shilov V. P. 500. Shilova A. 366. Shimanouchi T. 59. Shimizu H. 248. Shimoda H.357. Shimoji M. 356. Shimonis I. V. 355. Shin H. K. 29 30. Shindo M. 333. Shiner V. J. jun. 115. Shiotani A. 441 450. Shipatov V. T. 315. Shirado T. 41 1. Shirai T. 342. Shirk J. S. 49. Shlyapnikov D. S. 257. Shobatake K. 55 255. Shokol V. A. 323. Shoosmith J. 172. Shopov D. 235. Shore S. G. 264. Shoroshev Y. G. 32. Shortland A. 443. Shou J. K. 345. Shporer M. 339. Shreeve J. M. 317. 349. Shriver D. F. 276 420. Shtan’ko V. F. 351. Shu P Z - 9 Shul’man ’. 355. Shur V. B. 4b-Shurvell H. F. 405. Shustorovich E. M. 382. Shuvalov N. 366. Shuvalova N. 366. Shvets V. A. 21 8. 317 360. Sidebottom H. W. 168, Sidorenko Y. N. 209 210. Sidorova A. I. 337. Siebert H. 360. Siedle A. R. 266 271. Siefert E. E. 191. Siegbahn H.459. Siegbahn K. 459. Siegbahn P. 21 340. Siekierska K. E. 388. Silber H. B. 505. Silbert M. 191. Sill G. A. 213. Sills R. J. C. 358. Silver B. L. 56 343. Silver J. 315. Silverthorn W. E. 463, 477 483. Silverton J. V. 346. Silverwood R. 182. Silvestri A. J. 21 5. Sim W. 323. Simmons E. L. 119. Simmons J. D. 134. Simmons J. H. 43. Simon F. 363. Simon W. 83. Simonetta M. 18. Simons G. 15. Simons J. P. 155 168 171. Simons J. W. 185 191. Simonsen S. H. 372. Simpson J. 302. Simpson K. A. 396. Simpson W. I. 285. Sinanoglu O. 7. Sinclair R. S. 330. Sing K. S. W. 232 233, Singal S. P. 32. Singer R. J. 332. Singh B. K. 35. Singh D. 344. Singh G. 371. Singh H. 402. Singh M. 371. Singh M. M. 436. Singh O.336. Singleton E. 430 488. Sinha A. I. P. 317. Sinha S. C. 33. Sinitsyna S. M. 377. Sinn E. 61 74 77. Sinyagin V. I. 377. Sirota A. M. 336. Sisido K. 310. Skalkina. L. V 214. Skapski A . C 74.78. 392, Skelton B. W. 488. Skillman L. 13. 179. 249. 443 49 1 540 Author Index Skougstad M. W. 336. Slade R. C. 65 66 67 68, Slade R. M. 435 448. Sladky F. O. 362. Slagle 0. D. 44. Slanger T. G. 136 140, Slater J. A. 265. Slater J. C. 13 16. Slater J. H. 276. Slater J. L. 424. Slivnik J. 345 362. Slocum D. W. 469 474. Sloczynski J. 229. Slutsky L. J. 121. Smail T. 192 193. Smail W. R. 69 72. Small R. 119. Smardzewski R. R. 53. Smart J. C. 272. Smart M. L. 73. Smedal H. S. 485. Smeggil J. G. 258. Smid J. 255. Smirnova S.A. 474 476. Smit W. 344. Smit W. M. A. 320. Smith A. 187. Smith A. J. 370. Smith B. C. 326. Smith B. E. 265 476. Smith C. F. 453. Smith C. L. 117. Smith C. P. 324. Smith D. 119. Smith D. C. 381. Smith D. E. 270. Smith D. J. 140 165 335, Smith D. W. 378. Smith F. C. jun. 14. Smith G. F. 120. Smith G. G. 188. Smith G. J. 397. Smith G. L. 267. Smith H. O. 1 1 . Smith I. W. M. 141 149, Smith J. A. S. 278. Smith J. D. 276 287 473. Smith J. E. 325. Smith J. V. 198. Smith K. 261 275. Smith K. M. 294. Smith K. W. 114. Smith L. 312. Smith M. D. 103. Smith M. J. 321,447,464, Smith N. A. 25. Smith N. E 377. 73 77. 142 155. 342. 155. 465. Smith P. J. 31 1 3 12 387. Smith P. W. 75 394. Smith S. A. 452. Smith T.D. 315 374. Smith W. H. 163. Smutek M. 339. Snaith R. 288. Sneeden R. P. A. 443,458. Snelling D. R. 164. Snow M. R. 378,430. Snyder D. A. 484. Snyder J. P. 407. Snyder L. C. 2 1. Sobeir M. 343. Sohma K. 293. Sohn Y. S. 79 473 474. Sokolov V. B. 361 362. Sokolova J. A. 381. Solc M. 499. Solly R. K. 176 177 182, Solo R. B. 152. Solodar J. 461. Solomon J. J 282. Solovyev. V . A, 35. Soltys J. F. 179. Somers J. H. 322. Somieski R. 326. Sommer K. 331 332. Sommer L. H. 301. Somorjai G. A. 54. Somsen G. 83. Sondengam L. 214. Sonin V. I. 351. Sonnichsen G. 109. Sonoda T. 21 8. Sonogashira K. 45 1. Soriano J. 359. Sorokin V. E. 44. Sorokin V. N. 129. Southern J. F. 477. Spalding T. R. 102 279, Spanninger P. A. 281.Spencer A. 389. Spencer J. L. 426 478. Sperber G. 20. Spialter L. 298. Spicer L. D. 176. Spielvogel B. F. 259. Spiess H. W. 423. Spinney H. G 316. Spiridonov V. P. 382. Spiro T. G. 394 400. Spitsyn V. I. 351. Spittler J. M. 363. Spohn R. J. 426. Spohr R. 354 362. Spratt R. 466. Springer C. S. 289. Spurlock L. A. 27. Squire D. A. 413. 190. 302. Squire R. 11. Sramkova B. 497. Srinivasan L. 409. Srinivasan R. 187. Srivastava F. N. 313. Srivastava S. C. 256. Srivastava T. N. 294. Srivastava T. S. 410 505. Stacey V. 128. Stadelmann W. 324. Stainbank R. E. 435 436, Stairs R. A. 254. Stallard J. M. 33. Stamires D. N. 218. Stamper J. G. 354. Standlest R. 217. Stanko J . A. 379 424. Stanko V. I. 272. Staples P.J. 109. Stark F. O. 301. Starkey B. J. 413. Starunov V. S. 44. Starz E. 299. St. Clair D. 270. Steadman C. J. 84. Stebbings R. F. 127. Stechemesser R. 244. Stedman D. H. 124. 179. Steele J. C. H. jun. 322. Steer I. A. 331. Steer R. P. 165. Stefani L. 419. Stegeman G. I. A,. 32. Stegmann H. B. 308. Steinbach F. 245. Steinborn D. 334. Steiner E. 3. Steinfeld J. I. 155 156, Steinfink H. 309 384. Steinhoff G. 321. Stelzer O. 324 430 43 I . Stenson J. P. 438. Stephens M. 282. Stephens P. J. 340. Stephens R. S. 279. Stephens R. W. B. 30. Stephenson I. L. 178. Stephenson J. C. 3 1 . Stephenson L. M. 186. Stephenson N. C. 397, Stepin B. D. 367. Stern M. J. 112. Stetter K. H. 487. Steudel R. 298. Stevens K. W. H 63. Stevens R.M. 22. 259. Stevenson C. D 149 152. Stevenson R. L 219. 450 479. 171. 410. 155 Author Index 54 1 Stewart J . J. 278. Stewart P. A. M. 44. Stewart R. 108. Stewart R. F. 340. Stewart R. P. 425. Stewner F. 278 314. Stezowski J. J. 287 374, Sthapak J. K. 497. Stibr B. 265. Stich H. 451. Stidham H. D. 353. Stief L. J. 155. Stillinger F. H. 91 337. Stillings M. 340. St. John G. A. 136 142. Stobart S. R. 481. Stocco G. C. 450. Stocks J. 397. Stocker F. 308. Stoessinger R. 394. Stohrer W.-D. 186. Stoicheff B. P. 32. Stoll K. 328. Stomberg R. 375 382. Stone A. J. 12 386. Stone F. G. A. 282 420, 428 444 446 454 477, 486. 490. Stone F. S. 228 244, 400. Stone H. H. 280. Stone R. G. 345. Storace A. P. 413.Storch W. 273. Storey P. M. 340. Storhoff B. N. 27 1 . Storr A. 287 288 290. Stothers J. B. 449. Stotz R. W. 400. Stoufer R. C. 400. Strachan P. M. 156. Strafford R. G. 259. Stranks D. R. 502. Stratton W. J. 395. Strausz 0. P. 132 133, 138 144 145 147 156, 181 190 191. Strehlke B. 182. Strehlow H. 120. Streib W. E. 381. Streitwieser A. jun. 109, Stretton J. L. 29. Strobel D. F. 137. Strocko M. J. 324. Strohmeier w. 436. Strope J . H. 295. Strouse C. E. 484. Struchkov Yu. T. 314, 442 470 490. Struik L. C. E. 42. 473. 478. Strukl J. S. 410. Strukov 0. G. 325. Stryker L. J. 249. Stucky I;. D. 67 253.257, Studier M. H. 251 339. Stuehr J. 107. Stufkens D. J. 352 353. Stuhl F. 142 164. Stungis G. E. 280. Sturm J.E. 167 422. Stynes D. V. 310. Su S. R. 433. Suart R. D.,,171 177. Subrahmanyam V. S. 239. Subramanian S. 330 337, Suchy H. 277. Sudmeier J. L. 506. Siili A. 227. Suhara M. 345. Sulaiman W. 506. Sullivan J. F. 79. Sullivan R. F. 207. Sun K. K. 454. Sunder W. A. 179. Sundermeyer W. 304,349, Surd D. J. 504. Surles T. 359. Susa K. 309. Sustmann R. 10. Susz B. P. 374. Sutcliffe B. T. 25. Sutcliffe G. D. 285. Sutherland H. H. 290. Sutin N. 93 120 505. Sutton D. 375 486. Suzuki S. 339. Svec iI. J. 422. Svec J. 352. Svehla R. A. 30. Svensson I.-B. 375. Svensson. L. A 107. Swaddle T. W. 502 503. Swannick M . G. 440. Swanson B. 159,276.484. Swede R. J. 498. Sweet F. 243. Swerdloff M. D. 114. Swierczewski G. 321. Swift D.R. 394. Swift P. 473. Swindell R. F. 317 349. Swinehart J. H. 494,499. Swinzow G. 338. Switkes E. 259. Switkes E. S. 41 3. Swoboda P. 295 422. Syamal A. 376 506. Sykes A. G. 292,494,495, 374. 361. 407. 504. Symon D. A. 474. Symons E. A. 108. Symons M. C. R. 88,254, 293 299 316 319 330, 337 340 355 360 361, 383 470. Syrnikov Yu. P. 337. Sytnyk W. 171. Szalkowski F. J. 54. Szasz L. 15. Szilagyi I. 185. Szwarc M. 105 106 120. Szymanski J. T. 313 398. Tabacchi R. 442. Tabor B. F. 95. Tabuchi D. 3 1. Tachikawa E. 192. Tada H. 291. .Tamer C. 487. Taft R. W. 318. Tagliavini G. 313. Taguchi R. T. 191. Taira Z. 282. Tait J. M. 200. Takahashi H. 203 217. Takahashi S. 335. Takahashi Y. 482. Takanashi A. 342.Takanashi S. 209. Takano T. 491. Takats J. 470. Takayasu M. 209. Takechi H. 107. Takemoto J. 56 380 487. Taketomi T. 475. Tal’rose V. L. 356. Tamain B. 366. Tamaru K. 248. Tamborski C. 453. Tamm K. 39. Tamura M. 459. Tanaka H. 116. Tanaka I. 127 155 336. Tanaka K. 248,294 314. Tanaka T. 314. Tanaka Y. 136. Tananaev I. V. 294. Tandon K. N. 315. Tandon U. S. 35. Tanfield P. J. 479. Tang I. N. 338. Tang S. C. 379. Tang Y.-N. 192. Tango W. J. 156. Tanguy B. 3 15. Tanhauser R. S 241 542 Author index Tani H. 288. Tani K. 321,448,464,466. Tannaka Y. 37. Tanner D. W. 243. Tapping R. L. 429. Taqui Khan M. M. 488. Tarabarina A. P. 305. Tarama K. 464. Tarasov V. P. 405. Tarsekar V. K. 33. Tartaglia P. 35 36. Tashmukhamedov F.35. Taskoprulu N. S. 43. Tatsumoto N. 38 121. Tatsuno Y. 408 486. Taube H. 297 381 389, 391 402 415 494 495, 499 501. Taubert R. 257. Tauzher G. 413 419. Taylor D. W. 401. Taylor E. W. 44. Taylor G. W. 191 297. Taylor H. 120. Taylor H. F. W. 306. Taylor J. C. 372. Taylor J. E. 29. Taylor K. 374. Taylor M. R. 409. Taylor P. 334. Taylor R. 116. Taylor R. C. 262. Taylor R. S. 292,494,495. Taylor S. H. 460. Tebbe F. N. 471 479. Tedder J. M. 179 181, Teggins J. E. 497. Teichner S. J. 228 231, 232 236 249. Tellinghuisen J. B. 152. Temkin 0. N. 451. Tempere J. F. 213. Templeton D. H. 257, Tench A. J. 247 355. Teodorescu M. 245. Teranishi S. 217. Terzis A. 394. Tewari K. C. 121. Thackeray J. R. 77. Thakur C.P. 326. Thakur S. N. 345. Tham W. S. 426. Thamm H. 328. Thankarajam N. 415. The N. D. 91. Theriot L. J. 75 376. Thevenot F. 284. Thiebault A. 356. Thiede K. 293. Thiel W. 316. 182. 270. Thiele K. H. 441 442. Thistlethwaite P. J. 156. Thoen J. 33 35. Thomas B. S. 285 287, Thomas C. K. 424. Thomas C. L. 216. Thomas G. 256. Thomas H. C. 98. Thomas J. H. 182. Thomas K. M. 298. Thomas T. W. 396. Thompson D. T. 430. Thompson D. W. 374, Thompson H. B. 359,363. Thompson J. A. J. 481. Thompson J. C . 302. Thompson J. F. 305. Thompson K. R. 294. Thompson L. K. 487. Thompson M. L. 269. Thompson R. C. 72 360. Thompson W. K. 338. Thomsen M. E. 466. Thomson C. 3 19. Thomson J. 458. Thorneley R. N. F. 504. Thornley A.S. 379. Thornley J. H. M. 63. Thorpe F. G. 262. Thorpe P. L. 31. Thrush B. A. 124 136, 149 154 155 156 191. Thusius D. 504 505. Thynne J. C. J. 182. Tieghi G. 466. Tietze W. 132. Tigelaar H. L. 345. Tillett J. G 110. Timimi B. A. 120. Timlin D. M. 179. Timms R. E. 298. 505, Timoshchenko N. 352. Ting C. T. 192 193. Tinsley S. W. 287. Tisley D. G. 384. Titov S. S. 326. Titus D. D. 479. Tkach E. F. 499. Tkachev V. V. 381. Tkatchenko I. 465. Tobe M. L. 504. Tobias R. S. 295 450. Tobiasz T. 229. Toby S. 177. Todd L. J. 265 266 271. Todd S. M. 328. Tok G. C. 315. Tolman C. A. 465. Tom A. 30. 288. 411. 507. Tomalsky R. E. 167. Tomasek M. 244. tom Dieck H. 423 487. Tomishko A. G. 336. Tomkins I. B. 431 444.Tomlinson A. A. G. 383. Tomlinson D. J. 103. Tomlinson C. 116. Tomus E. J. 83. Tondello E. 414. Toney J. 257. Tong D. A. 278. Tong E. 44. Tonnet M. L. 72. Topart J. 3 13. Topchieva K. V. 203 2 1 I . Topor M. G. 183. Topp M. R. 173. Torii A. 423. Torii Y. 390. Torki M. R. 378. Toropova M. A. 361. Torsi G. 289. Tossell J. A. 259. Toth L. M. 371. Toth M. 190. Touhara H. 357. Tournayan L. 395. Towl A. D. C. 11,449. Townsend R. P. 218. Toy M. S. 340. Tsang W. 185 190. Tsao P. 58 362. Tsay Y. H. 447 467. Tseung A. C. C. 235. Tsibris J. C. M 413. Tsitovskaya I. L. 217. Tsolis E. A. 324. Tsuboi M. 59. Tsutsui M. 419. Tsutsumi K. 203 217. Tsutsumi S. 491. Traber D. G. 89. Trambouze Y. 206. Tranter R. L. 1 1 I 120.Trautwein W.-P. 322. Travers N. F. 264 270. Traverso O. 474. Trecker D. J. 190. Treichel P. M. 438. Tremillon B. 353. Trenwith A. B. 185. Tret’yakova K. V. 353. Treushnikov E. N. 306. Tricker M. J. 481. Trinh-Toan 488. Tripathy P. B. 462. Tripodi R. 30. Trofimchuk A. K. 358. Trofimenko S. 259,448. Trombetti A. 316 344. Trooster. J. M. 387 Author Index 543 Trotman-Dickenson A. F., 123 124 175 180 182, 187. Trotter J. 290 313 326, 398 434 435. Troughton P. G. H. 73. Trovati A, 428. Trozzi M. 449. Truell R. 27. Truhlor D. G. 1 1 1 . Truter M. R. 255 324. Trysberg L. 382. Tuck D. G. 292. Tucker N. I. 462. Tucker P. A. 326. Tudor R. 273. Tuggle R. M. 463. Tumanov Yu. N. 345, Tung S. E. 218. Turco A. 414 437.Turcotte J. 429. Turkevich J. 195 203, Turley J . W. 396. Turnbloom E. W. 320. Turner G. E. 369. Turner J. J. 295 340 360, 393 42 I 483. Turner R. C. 506. Tursi A. J. 336. Tusch R. 85. Twist P. J. 265. Tyerman W. J. R. 147, 155 168. Tyson J. 58. 404. 218. Tytko K.-H. 382. Uchida N. 351. Uchida Y. 447. Udovich C. 56 393. Udy P. B. 326. Ueda S. 466. Uegaki E. 293. Ueno K. 372. Uernura S. 293. Ugi I. 324. Ugo R. 404,435,452,479, 486 489. Ugorets M. Z. 35 1 . Uguagliati P. 419 428, Uhlenbrock W. 304. Uhlig D. 491. Ukhin L. Yu. 408 483. Ukihashi H. 203 345. Ulbricht H. 85. Uller W. 432. Ullmann R. 43. 462. Ulrich S. E. 313. Ummat P. K. 340 350, Underhill A. E. 396 397. Ungermann C. 268. Unsworth W. D.314. Urbach F. L. 404. Urch D. 192. Urch D. S. 252. Urland W. 41 1. Urushiyama A. 379. Urusova M. A. 96. Urwin D. 249. Ushio M. 284. Ustynyuk Yu. A. 447. Uttley M. F. 487. Utyanskaya E. Z. 119. Uytterhoeven J . B. 205. 402. Vaciago A. 74. Vaglio G. A. 426. Vahrenkamp H. 275,43 1, Vaidya 0. C. 340 350. Valade J. 300. Valentine D. jun. 390, Valentine J. S. 390 489. Valigi M. 241. Val’karsel G. 367. Vallauri M. E. 338. van Benthem W. 133. Van Dael W. 33 35. van der Bergen A. 412, van der Bergh H. E. 171, Van der Bogaerde J. 156, van den Ven L. J. M. 188. van der Heyden B. G. 378, van der Kelen G. P. 421. Vander Sluis K. L. 469. Van Derveer D. G. 390. Van der Veer W. 330. Van der Voet A. 49 351, Vanderzee C. E. 356.van Duijnen P. Th. 24. Van Dyke C. H. 307. Vangeel E. 33 35. Van Gilder R. L. 461. Van Hecke G . R 379. van Helden R. 466. van Leeuwen P. W. N. M., Van Nice R. 369. van Oven H. O. 478. 432. 489. 445. 177. 168. 352. 419. Van Remoortere F. B., Van Roodselaar A. 145. Van Sickle D. E. 214. van Tamelen E. E. 483. Van Veen R. 28 1 . Van Wazer J. R. 318 329. Van Wolput J. H. M. C., Van Zijill Langhout W. C., Varela A. 507. Varetti E. L. 317. Varshavskii Yu. S. 424, Varughese P. 355. Vas S. 363. Vasile M. J. 405. Vasil’eva T. V. 305. Vasilevskis J. 393 397. Vasilyus I. 44. Vasini E. J. 358. Vaska L. 436 488 489, Vasudev P. 352. Vaughan D. H. 392 501. Vaughan J. 116. Vedejs E. 458. Vedeneev V. I. 356. Vedrine J.247. Vegard L. 142. Veillard A. 21 22 330. Veith G. D. 498. Veith M. 304. Velasco R. 155 159. Velleman K.-D. 319. Venerable G. D. 500 501. Venkateswarlu T. 56. Venuto P. B. 195 199, 200 207 208 217. Veprek-Siska J. 499. Verkade J. G. 261 322, Verma R. D. 168. Vernon G. A. 380. Versmold H. 85. Vertes A. 369 496. Verwey E. J. W. 228. Veselovski V. I. 344. Vest R. W. 234 235. Viana C. A. N. 92. Vickery B. L. 255. Vickroy D. G. 358. Vickroy V. V. 458. Victor R. 468. Vidaei M. 506. Vidali M. 372 397. Vidoni Tani M. E. 351. Viehe H. G. 295. Vieth W. R. 216. Vietzke E. 144. Vigato. P. A. 372. 448. 310 314. 350. 212. 436. 501. 323 544 Author Index Vijh A. K. 249. Vikis I. C. 13 I . Villa J. F. 68 73 74 75.Villiger H. 200. Vincent A. T. 320. Vincenti W. G. 30. Vink H. A. 496. Vinogradova 0. M. 217. Vinot G. 21 330. Virmani R. N. 350. Vishnevskaya L. M. 21 1. Visser J. P. 461. Viste A. 498. Viswanathan N. 307. Vitulli G. 466. Vitzthum V. 252,346,412. Vleek A. A. 429. Vollenkle H. 309. Voelter W. 487. Vogel P. C. 112. Vogrin F. J. 88. Vohra A. G. 399. Voisey M. A. 187. Vojtik J. 12. Volkenburgh G. V. 127, Volkova L. G. 446 45 1. Vollmer H. 326. Volodin A. A. 326. Volpi G. G. 136. Vol’pin M. E. 442 445, Volterra V. 32 86. Volynskii N. P. 342. von Ammon R. 469. von der Muhll R. 405. Von Dreele R. B. 309,374. von Halasz S . P. 348 349. von Goldhammer E. 85. Vonnahme R. L. 464. von Niessen W. 21. von Schnering H. G.381, Voorhies A. 212. Voorhoeve R. J. H. 249. Voronel A. V. 35. Voronkov M. G. 304,318. Voronov V. P. 35. Vostokov I. A. 31 1. Voyevodskaya T. I. 447. Vrieze K. 419. 155. 446 483. 405. Waage E. V. 176 177. Waber J. T. 13. Wada G. 496. Waddan D. Y. 415. Waddell B. V. 13 1. Waddington D. 35 39, 337. Waddington T. C. 474. Wade K. 259 276 277, Waggett S. V. 77 376. Wagner A. J. 326. Wagner C. 249. Wagner E. L. 11. Wagner H. G. 124 335, Wahl A. C. 22 166 359. Wahlgren V. 2 1. Wahr J. C. 354. Wai C. M. 192. Wailes P. C. 419,450,470, Waite D. W. 264. Wakatsuki Y. 461. Waldman M. C. 308. Walker A. 308 313. Walker D. J. 277. Walker R. W. 184. Walker S. 37. Walker T. E. H. 21. Wall D. H. 11. Wallace W. J. 423. Wallart F.346 355. Wallbridge M. G. H. 263, 268 338 352 354 358, 438. Wallwork S. C. 252 385, 411. Walmsley D. E. 261 507. Walrafen G. E. 91 337. Walsh B. 37. Walsh E. J. 328. Walsh H. C. 263. Walsh R. 177 182 183, Walter J. L. 410. Walters E. A. 113. Walther B. 293. Walton A. W. 121. Walton D. R. M. 302. Walton J. C. 179. Walton R. A. 384. Wampler F. B. 179. Wan C. 287. Wan J. K. S . 171. Wan K. Y. 459. Wanczek K. P. 344. Wandiga S. O. 307. Wang J. T. 393. Wang P. L. 498. Wang R. T. 495. Wannagat U. 290 303, Ward B. 17 1. Ward J. S. 468. Ward J. W. 202 210. Wardell J. L. 3 1 1. Wardle R. 397 476. Ware M. J. 56. 288. 340. 489. 185 187. 306. Waring C. E. 179. Warnatz J. 340. Warnqvist B. 293 391. Warren J.L. 352. Warren K. D. 406. Warren L. F. 270. Wartel M. 345. Washburne S. S. 301. Washida N. 336. Wasii S. 343. Wasserman E. 183. Wassermann A. 474. Watanabe H. 239. Watanabe N. 357. Watanabe T. 423. Waterman H. 73. Waters J. A. 458. Waters J. H. 401 497. Waters J. M. 400 484. Waters T. N. 375 400, Waterworth L. 291. Wathen C. A. 369. Watkins K. O. 497. Watkins K. W. 183. Watkins P. M. 354. Watson J. K. G. 56. Watson R. E. 13. Watson R. N. 116. Watson R. T. 152. Watt R. 443. Watt W. S. 126. Watts J. B. 415. Watts J. H. 292. Watts W. E. 427. Wauchop T. S. 127. Waugh A. B. 384. Wayne R. P. 155 164, Weatherburn D. C. 501. Weaver D. L. 463,484. . Weaver J. 468. Webb G. A. 61 62 367. Webb S. B. 329. Weber H.419. Weber J. H. 445. Webster B. C. 340. Webster D. E. 455. Webster J. R. 310. Webster 0. W. 296. Webster W. 332. Wedd A. G. 487. Wedd R. W. J. 313. Weeda L. 83. Weekes J. E. 323. Weeks R. W. jun. 193. Wei I. Y. 478. Weichmann H. 319. Weidlein J. 33 1. Weigold H. 450 489. Wed J. A. 362. Weil J. L. 366. 488. 165 Author Index 545 Weiler R. 43. Weingard C. 328. Weinreich G. H. 343. Weisberg J. 247. Weiss A. 254. Weiss A. H. 204. Weiss R. 255 257 485. Weiss S. 120. Weisz P. B. 195 200 207. Welch M. J. 316. Welge K. H. 142 144 155, 163 164 336. Weller F. 287 316. Wells C. F. 498. Wells D.,,475. Wells P. B. 455. Wells P. R. 315. Wells R. L. 277. Welsh A. G. 29. Weltner W. jun. 294. Wen W. Y. 90 106. Wendlandt W.W. 315. Wennerstrom H. 355. Wenning U. 128. Wentrup C. 342. Wentworth W. E. 92. Werner G. K. 469. Werner H. 439 476. Wesley R. D. 367. West B. O. 78 412 433, West R. 254 304 308, Westberg H. H. 456. Westlake D. J. 433. Weston R. E. 192. Weston R. V. 125. Westwood N. P. C. 298, Wexell D. R. 399 497. Wharton E. J. 490. Wheatley P. J. 320 329, Wheeler B. R. 395. Whewell R. J. 92. Whimp P. O. 443 444, White A. F. 166. White A. H. 386. White A. J. 180 182. White C. 471 477 479. White D. A. 416 460. White D. L. 462. White D. W. 261 322, White G. 291. White J. C. B. 295. White J. D. 391 495. White J. W. 85 428. White R. D. 121. White R. P. jun. 428. Whitear. B. R. D. 457. 445. 476. 299. 491. 462. 329.Whitehurst P. W. 121. Whitesides G. M. 458, Whitesides T. H. 478. Whiting F. L. 335. Whitlock H. W. jun.,468. Whitlock R. F. 256. Whitlow S. H. 338. Whitney E. D. 254. Whitt C. D. 256 286. Whitten J. L. 21. Whittle E. 177 179 181. Whittle K. R. 484. Whittle M. J. 359. Whyman R. 61 74 75. Whyte T. E. jun. 199,207, Whytock D. A. 179. Wiberg E. 259. Wiberg K. B. 498. Wiberg N. 304. Wickham G. R. 102. Wieghardt G. 360. Wiersema R. J. 266 270. Wiersma S. J. 355. Wies R. 303. Wiesenfeld J. R. 136 137, Wiest R. 485. Wiezer H. 3 1 1. Wiggen J. P. 447. Wiggins J. W. 273. Wilairat P. 499. Wilder R. L. 379. Wilhelm E. 341. Wilhite D. L. 21. Wilhoit R. C. 336. Wilke G. 465 488. Wilkie C. A. 286. Wilkins J. D. 373 441.Wilkins R. G. 394 502. Wilkinson G. 389 441, 443,451 465 491. Wilkinson J. G. 340. Wilkinson W. 413. Willemsens L. C. 316. Willey S. R. 271. Williams A. G. 452. Williams B. C. 294. Williams D. J. 290. Williams D. L. 305. Williams F. 330. Williams F. J. 456. Williams F. R. 445. Williams G. J. 130 132. Williams G. R. 10. Williams H. J. 77. Williams I. G. 434. Williams J. E. 10. Williams J. L. R. 275. Williams J. M. 90 362. 459. 208. 271. 148 149 154 156. Williams R. 54. Williams R. E. 267. Williams R. J. P. 294 385, Williams R. L. 193. Williamson S. M. 317. Willing R. I. 338. Willis C. J. 405. Willis M. 329. Wilputte-Steinert L. 421. Wilson G. L. 276 322. Wilson I. L. 287. Wilson J. W. 289. Wilson L. J. 41 1.Wilson P. W. 305 307, Wilson S. E. 455 456. Wilson S. T. 484. Wilson T. M. 13. Wilson V. A. 490 491. Wilson W. E. 163. Wilson W. E. jun. 180. Winfield J. M. 382 406. Wingfield J. N. 277. Winkler C. A. 136. Winograd N. 496. Winstein S. 468. Winter G. 316. Winter N. W. 21 25. Winter T. G. 23 30. Winterton N. 458. Winton K. D. R. 179. Wipff G. 21. Wirl A. 489. Wise W. B. 121. Wiseman T. J. 249. Wismar H. J. 290 303. Wittmann A. 309. Woessner W. D. 468. Wojcicki A. 433. Wojciechowski W. 61. Wold S. 102. Wolf A. P. 134 299. Wolfgang R. 19 1 192 193. Wolfrum J. 124 335. Wolfsberger W. 288 303, Wolkenstein F. F. 242. Wolkenstein Th. 244. Wolters A. P. 431. Wong A. C. 265. Wong C. S. 392. Wong G. T. F. 268. Wong S.M. 118. Wong S. R. 171. Wong W. H. 192. Wood D. C. 101. Wood J. H. 13. Wood J. L. 289. Wood J. S. 63. Wood P. M. 130 131 160, 445. 309. 304. 161 168 546 A u th or Index Wood R. E. 3 1. Wood R. H. 96 98. Wood S. E. 262. Woodhouse E. J. 343. Woods M. 321 326. Woodward P. 455 468. Woodward R. B. 182,186. Woody R. W. 413. Woon-Fat A. R. 150. Wooten C. W. 331. Wormald J. 343 41 3 425, Worrall I. J. 289 291. Worrell J. H. 494. Worsley I. G. 375. Worthington B. N. 338. Wozniak B. 441. Wray K. L. 345. Wright C. J. 428. Wright G. J. 116. Wright S. 472. Wrighton M. 421. Wristers J. 455. Wu E. L. 199 207 208. Wudl F. 340. Wulfsberg G. 476. Wyn-Jones E. 36 37. Wynne K. J. 352 353. 480 489. Yablokov V. A. 305. Yablokova N.V. 305. Yager W. A, 183. Yagupsky G. 465. Yakovleva E. A. 119. Yale H. L. 281. Yamada O. 289. Yamada S. 72. Yamaguchi G. 289. Yamaguchi H. 456. Yamaguchi M. 412. Yamamoto A. 458 483. Yamamoto J. 286. Yamamoto K. 300 482, Yamamoto T. 398 458. Yamazaki H. 434. Yamazaki K. 209. Yamdagni R. 86. Yanagita M. 331. Yandell J. K. 293. Yardley J. T. 171. Yarkova E. G. 315. Yarsimirskii K. B. 499. 494. Yarwood A. J. 155. Yashima T. 209 21 1. Yasuda H. 288. Yasuda K. 291. Yasufuku K. 434. Yasunaga T. 38 121. Yasuoka N. 288,463. Yates K. 109. Yawney D. R. W. 73. Yeager E. 86. Yeager Y. E. 39. Yeats P. A. 313. Yeatts L. B. 96. Yeddanapalli L. M. 242. Yee K. C. 322. Yee K. K. 138 155 156, Yeh C. 125. Yen Chu M.183. Yesinowski J. P. 461. Yevitz M. 379. Yip S. 44. Yoder C. H. 298. Yokoyama N. 178. Yoneda H. 412. Yonezawa T. 1 1. Yoshida T. 408 423 462, Yoshifuji M. 324. Yoshihara R. 496. Yoshimitsu T. 314. Yoshizawa N. 496. Young A. T. 115. Young D. A. T. 271,272. Young D. E. 277 329, Young L. B. 104. Young M. K. 292. Young P. J. 133 138 156. Young R. A. 127 136, 142 155. Younger D. 342. Yu S. 257. Yurkevich A. M. 446. Yurzhenko T. I. 323. 168. 486. 331. Zaborowski L. M. 317, Zadorojny C. 107. Zahorszky U. I. 468. Zahrobsky R. F. 309. Zaitsev B. E. 367. Zakharkin L. I. 119 272, 349. 285. 290. Zak Z. 35 1. Zakharova G. N. 314. Zakorska I. 83. Zalewski K. 135. Zalivchii V. N. 38. Zalkin A. 257 270. Zambonelli L.74. Zamora V. A. 327. Zana R. 40. Zanella P. 469. Zanganeh R. 299. Zanzoterra C. 425. Zare R. N. 128 155 156, Zaripov N. M. 322. Zarkadas A. 318. Zarlin P. M. 327. Zazzeta A. 477. Zdunneck P. 442. Zeck. 0 328. Zegzhda T. V. 355. Zeiss H. H. 443 458. Zeiss W. 323. Zeleznik F. J. 30. Zelonka R. A. 399 462. Zeltman A. H. 391. Zemva B. 362. Zener C. 135. Zentil M. 325. Zerina G. V. 287. Zetzsch C. 340. Zhigareva G. C. 272. Zhil’tsov S. F. 275 290. Zhukovskii A. P. 337. Zia A. 144 164. Ziehn K.-D. 323. Zimmerman G. O. 33. Zingales F. 428. Ziolkowski J. 223. Zipf E. C. 142. Zisman W. A. 221. Zisserman D. 133. Zocchi M. 408 466. Zolla A. 86. Zoltewicz J. A. 117. Zorina 0. M. 40. Zorn C. 362. Zuberbiihler A.501. Zubieta J. A. 387. Zuckerman J. J. 281 309, 310 313 327. Zupan J. 362. Zvara I. 365. Zwanzig R. 89. Zweifel G. 261 287. Zwolinski B. J. 336. Zyka J. 497. Zykova T. V. 323. 159

ISSN:0069-3022    

DOI:10.1039/GR9716800509

出版商:RSC    

年代:1971

数据来源: RSC