INORGANIC CHEMISTRY1. INTRODUCTIONTHE emphasis, noted in last year’s Report, on the chemistry of boron, silicon,phosphorus, and organometallic compounds has been maintained during1961, and these subjects again occupy a large proportion of the Report.There has, fortunately, been only a slight increase in the number of paperspublished in the inorganic field, and overall coverage has therefore againbeen possible. Since a report on crystallography is now to be publishedevery year, mention has been made of only a few structure determinationsof outstanding chemical interest.and organo-metallic compounds,2 the first volume of a revised edition of Brauer’sHandbook,3 and second editions of two textbooks on ~ a l e n c y . ~ A newabstract journal devoted to organometallics has a~peared.~ General ’reviews have been published on bond lengths and angles in inorganic com-pounds,6 valency-bond structures and hybridization in compounds of first-row elements,’ the structures of eight-co-ordination compounds, * thedimerization of inorganic free radical^,^ synthetic gemstones, lo and nuclearfission.l1New books include A.C.S. Monographs on perchloratesMany other reviews are mentioned elsewhere.D. W. A. S.A. G. S.2. TYPICAL ELEMENTSGroup 1.-The alkali-metal polyfluorides, reported to be obtained bythe action of fluorine on alkali-metal chlorides, have been shown to be fluoro-chlorites of formula MClF,, analogous to the well-known fluorobromites ;they react violently with water, and are decomposed by heat into the metalfluoride and chlorine trifluoride.A mass-spectrometric study of ethyl-lithium vapour suggests that the1 “ Perchlorates,” ed.V. Sauchelli, Reinhold Publ. Corp., New York, 1960.“ Organometallic Chemistry,” ed. H. Zeiss, Reinhold Publ. Corp., New York,1960.“ Handbuch der Praparativen anorganischen Chemie,” ed. G. Brauer, FerdinandEnke Verlag, Stuttgart, Vol. I, 1960.4 E. Cartmell and G. W. A. Fowles, “ Valency and Molecular Structure,” Butter-worths, London, 2nd edn., 1961; C. A. Coulson, “ Valence,” Oxford Univ. Press, 2ndedn., 1961.5 “ Organometallic Compounds,” Translation and Tech. Infn. Services, London.6R. J. Gillespie, J . Amer. Chem. SOC., 1960, 82, 5978; Canad. J . Chem., 1961,* R’. J. Gillespie, Canad. J . Chem., 1961, 39, 2336.See also, however, J. L. Hoard,9M. Green and J. W. Linnett, J., 1960, 4959.39, 318.G. L. Glen, and J. V. Silverton, J . Amer. Chem. Xoc., 1961, 83, 4293.H. A. Bent, Chem. Rev., 1961, 61, 275.loE. A. D. White, Quart. Rev., 1961, 15, 1.l1 G. N. Walton, Quart. Rev., 1961, 15, 71.____.______ _ _ -~IH. Bode and E. Klesper, 2. anorg. Chem., 1951, 267, 97.2L. B. Asprey, J. L. Margrave, and M. E. Silverthorn, J . Amer. Chem. SOC., 1961,83, 295580 INORGANIC CHEMISTRYpredominant species are the hexamer and tetramer;3 it seems probable thatthe bonding in these compounds is of the multicentre electron-deficient typethat occurs in beryllium and aluminium a l k y l ~ . ~ Potassium reacts withcyclo-octatetraene in tetrahydrofuran to yield an unstable white compoundK2CsHs,THF ; physicochemical evidence indicates the presence of a planarCsHs2- ion.The thermal stabilities of addition compounds of lithium boro-hydride and ethers decrease along the series tetrabydrofuran > dimethylether > diethyl ether > di-isopropyl ether, which suggests that the strengthof the ether as an electron-donor is the most important factor in determiningstability. Evidence has been obtained for the existence of an adduct con-taining two molecules of tetrahydrofuran. The various compounds formedwhen alkali metals dissolve in methanol have been thoroughly examined:lithium forms only LiOMe (which has a structure similar to that of lithiumhydroxide) ; sodium forms NaOMe and NaOMe,SMeOH ; potassium formsKOMe, KOMe,MeOH, and KOMe,3MeOH.' Other systems investigatedinclude those of potassium, rubidium or caesium, and antimony or bismuth,and pot assium-arsenic .Group II.-Basic beryllium nitrate, Be40(N03)s, is obtained as a volatileproduct of the decomposition of the anhydrous nitrate; this has been madeby the action of dinitrogen tetroxide on beryllium chloride in the presenceof ethyl acetate and subsequent decomposition of the adduct Be(NO3),,2N,O4.The similarity of its formula to that of the well-known basic acetate suggeststhat the nitrate groups are acting as bidentate ligand~.~ Several colouredcomplexes of 2,2'-bipyridyl or o-phenanthroline and beryllium alkyls orhalides have been described, and it is suggested that the colour arises fromthe transfer of an electron from the beryllium-containing molecule to thelowest unoccupied orbital of the organic compound; in the series bipyBeX,,where X = C1, Br, or I, decrease in the electronegative character of Xresults in an increase in the extinction coefficient.1° Macrocyclic 8-di-carbonyl beryllium chelates have been made by heating the correspondinglow molecular weight polymers; they inturn polymerise, on being heated abovetheir melting points, with the production oflinear chelate polymers, such as (l), whichare soluble in aromatic solvents.11Diethylmagnesium made from pure mag-nesium reacts with diborane to form the compounds MgH,(BH,Et), andMgH,Et(BHEt), for which hydrogen-bridged structures are suggested.l2Organomagnesium halides have been made in hydrocarbon media by re-& ; ; d o g - \ 0('I3 J.Berkowitz, D. A. Bafus, and T. L. Brown, J . Phys. Chem., 1961, 65, 1380.4 R. West and W. Glaze, J . Amer. Chem. SOC., 1961, 83, 3580.5H. P. Fritz and H. Keller, 2. Naturforsch., 1961, 16b, 231.6 T . L. Kolski and G. W. Schaeffer, J . Phys. Chem., 1960, 64, 1696.7P. J. Wheatley, J . , 1960, 4270.8G. Gnutzmann and W. Klemm, 2. anorg. Chem., 1961, 309, 181; F. W. Dornand W. Klemm, ibid., p. 189; F. W. Dorn, W. Klemm, and S. Lohmeyer, ibid., p. 204.9 C. C. Addison and A. Walker, Proc. Chem. SOC., 1961, 242.10G. E. Coates and S. I. E. Green, PTOC. Chem. SOC., 1961, 376.11R. W. Kluiber and J. W. Lewis, J. Amer. Chem. SOC., 1960, 82, 5777.14 R. Bauer, 2.Naturforsch., 1961, 16b, 557SHARPE: TYPICAL ELEMENTS 81actions between various alkyl and aryl halides and magnesium in theabsence of the usual ethereal catalysts, and it is noteworthy that theirempirical formulz approximate not to RMgX but to R,Mg2X; they maycontain both alkyl and halogen bridges. Unlike ethereal Grignard reagents,they react with titanium halides to form olefinpolymerisation catalysts. l3The chemistry of the alkaline-earth metal phosphates has been reviewed.14Cyclopentadienyl derivatives of these metals have been obtained by theaction of cyclopentadiene on the hydrides at 260-400" or, in the case ofcalcium and strontium, on the metals in the presence of tetrahydrofuranor dimethylformamide.15Group 1II.-Boron. Two new methods for the preparation of diboranehave been described: good yields are obtained by heating stannous chloridewith sodium borohydride a t 200-250°,16 and hydrogenation of alkylboronstakes place in the presence of the usual catalysts a t 150O.l' The success ofthe latter process depends upon the action of the hydrogen present at highpressure in inhibiting the pyrolysis of diborane.The exchange of deuteriumbetween diborane and dimethylaminodiborane is of order 0.5 and 1 withrespect to these reactants, suggesting the participation of borane radicalsin the rate-determining stage.l*Sodium borohydride can be made by the interaction of sodium, hydrogen,and dehydrated borax in the presence of quartz sand;l9 three reviews of thereactions of borohydrides have been published.19-21 Sodium borohydrideis not attacked by bromine in hexane or benzene at 80°, but iodine reacts,forming boron tri-iodide, sodium iodide, hydrogen iodide, and hydrogen ;with hydrogen iodide, sodium iodide, diborane, and hydrogen result.22Thiocyanogen in ether reacts with lithium or sodium borohydride to forma compound of formula MBH(NCS)3.23The '' diammoniate " of tetraborane has been re-examined and shownto have the structure [H2B(NH3),][B3H,],24 and the tetramethylammoniumsalt containing the same anion has been obtained by the sequence 25Et,S MeOH Me,N.OH MeOHB,,H,, + (Et,S),B,,H,, + Et,SB,H,, - Me,NB,H,, __+ Me,NB,H,.Tetraborane reacts with pyridiiie at 0" to form BH3,py and B2H4,py.26The passage of the hydride B,H, in an atmosphere of hydrogen through13D.Bryce-Smith and G. F. Cox, J . , 1961, 1175.l*R. TV. Murray and M. A. Aia, Chem. Rev., 1961, 61, 433.15E. 0. Fischer and G. Stolzle, Ber., 1961, 94, 2187.l6 W. Jeffers, Chem. and Ind., 1961, 431.l7 R. Klein, A. Bliss, L. Schoen, and H. G. Nadeau, J . Amer. Chem. SOC., 1961,l8 J. S. Rigden and W. S . Koski, J. Amer. Chem. SOC., 1961, 83, 552.l9 F. Schubert and K. Lang, Angew. Chem., 1960, 72, 994.zoH. Noth, Angew. Chem., 1961, 73, 371.21 H. C. Brown, Tetrahedron, 1961, 12, 117.2zF. Klanberg and H. W. Kohlschutter, Ber., 1961, 94, 786.2sF. Klanberg, Proc. Chem. SOC., 1961, 203.24 G. Kodama and R. W. Parry, J . Amer. Chem. SOC., 1960, 82, 6250.26V. I. Mikheeva and V. Y. Markina, Zhur. neorg. Khim., 1960, 5, 1977 [963].*83, 4131.B.M. Graybill, J. K. Ruff, and M. F. Hawthorne, J . Amer. Chem. SOC., 1961, 83,2669.*Page numbers in brackets refer to the English translation82 INORGANIC CHEMISTRYan electric glow discharge between copper electrodes results in the formationof a new hydride, B10H16, in which two B,H, units (each consisting of apentagonal pyramid of five boron atoms, with those in the basal planejoined by hydrogen bridges and carrying one unbridged hydrogen atom)joined by a B-B bond.,, Many new amine-substituted decaboranes havebeen reported.2s Other substitution products of the same hydride includethose in which the donor group is a sulphide, sulphoxide, phosphine oxide,amide, or thioamide ; 29 displacement reactions 30 show that the strengthof the bonding increases along the series Me,S < MeCN < Et,N*CN <HCO-NlVte, = AcNMe, < Et3N = py = Ph3P.Diborane, tetraborane, and decaborane react with sodium cyanideto form substituted borohydrides Na(H,BCNBH,), NaB,H,.CN, andNaBloHl,-CN, generally isolated as etherates. Diborane and ammoniumcyanide initially form a substituted borohydride, but hydrogen is then lostand the final product is the ammonia adduct of B,H5*CN.31 Friedel-Crafts methylation of decaborane takes place mainly in the 2- and 4-positions,to a less extent in the 1- and 3-positions; in nucleophilic attack by lithiumalkyls, however, 6-substitution predominates.When decaborane reactswith Grignard reagents two processes take place, formation of the deca-boranyl Grignard reagent and the hydrocarbon and, to a smaller extent,formation of the 6-aIkyl-de~aborane.~~The compound NaBEt, is obtained by the interaction of ethylsodiumand triethylboron, or ethyl chloride and triethylboron in the presence ofsodium, or ethylene and the sodium salt NaBHEt,; it is stable towardswater but is decomposed by acids; several homologues have also been pre-pared.33 Alkylboranes can be made from aluminium alkyls, lithium boro-hydride, and hydrogen halides or boron halides at atmospheric pressure andtemperatures in the range 100-175", and also by the action of hydrogenunder pressure on boron trialkyls (e.g., 2BR, + 5H, +P B,H5R + 5RH).34When B,B,Me, reacts with ethylene at room temperature the main pro-ducts are Me,BEt, MeBEt,, and BMe,; with 3,3,3-trifluoropropene the mainproducts are trimethylboron and dimethyl-3,3,3-trifluoropropylboron,(CF,*CH2*CH2-BMe,).35 I n the presence of 2,6-lutidine, 1 -alkylpenta-boranes-9 rearrange to the 2-alkyl compounds.36 Mass spectra of somelower boron alkyls have been reported.37The compound N,H,,BH, is obtained by the action of hydrazinium27 R. Grimes, F. E. Wang, R. Lewh, and W. N. Lipscomb, Proc. Nut. Acad. Sci.,28 H. C. Beachell and B. F. Dietrich, J . Amer. Chem. SOC., 1961, 83, 1347; B. M.SQ W. H. Knoth and E. L. Muetterties, J . Inorg. Nuclear Chem., 1961, 20, 66.30R. J. Pace, J. Williams, and R. L. Williams, J., 1961, 2196.31V. D. Aftandilian, H. C. Miller, and E. L. Muetterties, J . Amer. Chem.SOC.,32R. L. Williams, I. Dunstan, and N. J. Blay, J., 1960, 5006, 5012, 5016.33 J. B. Honeycutt and J. R. Riddle, J . Amer. Chem. Xoc., 1961, 83, 369.34 L. H. Long and A. C . Sanhueze, Chem. and Ind., 1961, 588; R. Koster, G. Bruno,35 J. M. Birchall, R. N. Haszeldine, and J. F. Marsh, Chern. and Ind., 1961, 1080.36T. P. Onak, J . Amer. Chem. Xoc., 1961, 83, 2584.37 D. Henneberg, H. Damen, and R. Koster, Annalen, 1961, 640, 52.U.S.A., 1961, 47, 996.Graybill and M. F. Hawthorne, ibid., p. 2673.1961, 83, 2471.and P. Binger, Annalen, 1961, 644, 1SHARPE: TYPICAL ELEMENTS 83sulphate on sodium borohydride in tetrahydrofuran ; its pyrolysis undercontrolled conditions leads to the formation of H,B-NH*NH*BH,, obtainedits a crystalline polymer stable to water and acids.38 Hydrazine and tri-methylboron give 1 : 2 (unstable) and 1 : 1 (stable) adducts. At 25" di-borane displaces trimethylboron from the 1 : 1 compound, forming 1,l-di-methyldiborane, hydrogen, ethylene, and a heterogeneous solid.39 At 100"hydrazine and tetra-alkyldiboranes react according to the equation 4OB,H,R4 +- K2H4 --+ R,B*NH*NH.BR, + 2H,.Several aminodiarylboranes , Ar,B*NR,, have been prepared by reac-tions such as2Ph2BC1 + SPU'H, + BNEt, + (Ph,B*NH,), + 2Et,NHClAr,BCl + LiNR, + Ar,B*NR, + LiCl2ArMgBr + Cl,B.NR, + Ar2B*NR, + MgC1, + MgBr,.When R = H the compound is dimeric in benzene or nitrobenzene; theother compounds are monomeric in both solvents.The correspondingphosphino- and arsino-boranes can be obtained by analogous routes; theyare much more stable to hydrolysis than the amino-~ompounds.~1 A com-parative study of the proton magnetic resonance spectra of compounds suchas Me,B*NMePh, PhClBONMe,, and PhB(NMe,), suggests that p , - p , B-Nbonding is largely responsible for the hindered rotation about the B-N bondin these substances. 4 2 Tri( alkylamino) boranes, di(alkylamino)arylboranes,and borazoles undergo a general transaminafion reaction with primary orsecondary mono- and poly-amines : 43)R*NR, + HNR', + )B-NR', + HNR,.Tetrakisdimethylaminodiborane, (Me,N),B*B(NMe,),, has been obtained bythe interaction of (Me,N),BCl and highly dispersed molten sodium ; it reactswith many amines in the same way as do monoborane derivatives, and isconverted by alcohols or phenols into esters of hypoboric acid.44The chemistry of borazoles has been reviewed with special reference toRussian work.45 Some exchange reactions of borazole have been studied:ND,, DC1, and DCN exchange deuterium for hydrogen attached to nitrogena t a rate comparable with the rate of addition of these compounds; D,, B,D,,and NaBD, exchange deuterium for hydrogen attached to boron; no ex-change is observed with D,S, C,D,, or PD,.46 Hexahydroborazole has beenprepared by reduction of the hydrogen chloride adduct of borazole with38 J.Goubeau and E. Ricker, 2. anorg. Chem., 1961, 310, 123.39 W. G. Paterson and M. Onyszchuk, Canad. J . Chem., 1961, 39, 2324.40H. Noth, 2. Naturforsch., 1961, 16b, 471.41G. E. Coates and J.G. Livingstone, J., 1961, 1000.4aG. E. Ryschkewitsch, W. S. Brey, and A. Saji, J . Amer. Chem. SOC., 1961, 83,1010; P. A. Barfield, M. F. Lappert, and J. Lee, Proc. Chem. SOC., 1961, 421.43 W. D. English, A. L. McCloskey, and H. Steinberg, J . Amer. Chem. SOC., 1961,83, 2122; H. Noth, 2. Naturforsch., 1961, 16b, 470.44 B. J. Brotherton, A. L. McCloskey, L. L. Petterson, and H. Steinberg, J . Amer.Chem. SOC., 1960, 82, 6242; B. J. Brotherton, A. L. McCloskey, J. L. Boom, and H. M.Manasevit, ibid., p. 6245; H. Noth and W. Meister, Ber., 1961, 94, 609.46B. M. Mikhailov, Uspelchi Khim., 1960, 29, 972 [459].46 G. H. Dahl and R. Schaeffer, J . Amer. Chem. SOC., 1961, 83, 303484 IN 0 RG AN1 C CHE iM IS TR Ysodium borohydride; it is a non-volatile solid stable in the ordinary atmo-sphere, and is insoluble in benzene but soluble in several more polar organicsolvents.47 Condensation of borazole by pyrolytic dehydrogenation leadsto the formation of B5N,H8 (m.p. 27-30') and B6N,Hl, (m.p. 59-60"),the B-N analogues of naphthalene and biphenyl, and several other com-pounds. 48BBB-Trialkylborazoles can be made by the interaction of trimethyl-amine, alkylboranes, and excess of ammonia in diethylene glycol dimethylether a t 100-150"; the reaction is catalysed by ammonium chloride.49Hexamethylborazole forms a n-complex with tetracyanoethylene. 5O Con-ditions for the convenient large-scale laboratory preparation of BBB-tri-chloroborazole from boron trichloride and ammonium chloride have beendescribed ; this compound is converted into cyano- and thiocyanato-com-pounds by treatment with silver cyanide and potassium thiocyanate, andindications of the formation of nitro- and nitrato-compounds have beenobtained in a study of its reactions with silver nitrite and nitrate.51 Borontrichloride, phosphoryl chloride, alcohols, and NN-dimethylhydrazine reactwith B-aminoborazoles to give B-chloro-, B-alkoxy-, and B-hydrazino-compounds. BBB-Triamino-NNN-triethylborazole, [*B(NH,)*NEt*],, isobtained in low yield when BBB-trichloro-NNN-triethylborazole reactswith ammonia in benzene.All reactants must be of high purity; the pro-duct, though not especially unstable towards heat, is highly sensitive tohydrolytic de~omposition.~2 Several unsymmetrically substituted bor-azoles have been obtained by displacement reactions, e.g., BBB-trisdiethyl-a,mino-NNN-triethylborazole reacts with ethylamine with displacement ofone diethylamino-gro~p.~3Boron trifluoride and hydrazine form a 1 : 1 adduct, but in tetrahydro-furan the 2 : 1 compound is also obtained; thermal decomposition of theformer yields nitrogen, ammonia, ammonium fluoroborate, and boronnitride,5* The compound CF,*BF, has been obtained by the action of borontrifluoride on the product of the interaction of potassium di-n-butylboronand trifluoroiodomethane in ether, and also (as an etherate) by the actionof CF3*SC1 on diborane. Trimethylamine displaces the ether, but borontrifluoride does not react, indicating that, as would be expected, CF,*BP2is a stronger Lewis acid than BF3.55 The perfluorovinyl compounds(CF,:CF)BF,, CF,:CF*BCl,, (CF,:CF),BCl, and (CF,:CF),B have been obtainedby the use of dimethylbisperfluorovinyltin for the introduction of theorganic groups.56 The compound formerly described as Et,NH*BP, is47G.H. Dahl and R. Schaeffer, J . Amer. Chem. SOC., 1961, 83, 3032.48A. W. Laubengayer, P. C. Moews, and R. F. Porter, J . Amer. Chem. Soc., 1961,49M. F. Hawthorne, J . Amer. Chem. Soc., 1961, 83, 831. 833.50N. G. S. Champion, R. Foster, and R. K. Rlackie, J . , 1961, 5060.51 G. L. Brennan, G. H. Dahl, and R. Schaeffer, J . Amer. Chem. SOC., 1960, 82,52 I<. Niedenzu, D. H. Harrelson, and J. W. Dawson, Ber., 1961, 94, 671.53M. F. Lappert and M. K. Majumdar, Proc. Chem.Soc., 1961, 425.54 W. G. Paterson and M. Onyszchuk, Canad. J . Chem., 1961, 39, 986.55T. D. Parsons, E. D. Baker, A. B. Burg, and G. L. Juvinall, J . Amer. Chem.6 6 s . L. Stafford and F. G. A. Stone, J . Amer. Chm. SOC., 1960, 82, 6238.83, 1337.6248.SOC., 1961, 83, 250SHARPE: TYPICAL ELEMENTS 85actually the salt Et,NH,+ BF4-; the adduct has now been described andshown to resemble the numerous other compounds of boron trifluoride withamines.57 The oxfluoride B303F3 has been shown to have a cyclicstructure. 58Diboron tetrachloride can be obtained by the action of boron trichlorideon the oxide (BO), at 230°;59 details of its reactions with amines, nitriles,ethylene oxide, oxygen, and hydrazine have been described. With nitricoxide, a 1 : 1 adduct is formed; this decomposes at -40°, yielding a com-pound B,(NO),,BCI, from which the boron trichloride can be removed bypumping or by the action of trimethylamine; the solid residue of composi-tion B2N303 is thermally stable.60 With naphthalene, the compoundCl,H,,2B2C1,, which appears to contain four BCl, groups added to the samering, is produced; with benzene, an unstable product which quickly decom-poses to form phenylboron dichloride is obtained.s1 Evidence for theexistence of the B2ClG2- ion has been obtained in the conductimetric titra-tion of diboron tetrachloride in liquid hydrogen chloride with tetramethyl-ammonium chloride and the isolation of the compound (Me4N),B,Cl,.62Tetra-chloro- and -brorno-borates of diazonium and other large organiccations have been described.63Alkali and alkaline-earth metals and their nitrides have been found tobe effective catalysts for the conversion of hexagonal boron nitride intothe cubic form.64 When boron nitride is heated with lithium or calciumnitride or barium amide a t 700-1000 O , ternary nitrides Li3BN,, Ca3B,N4,and Ba3B2N4 are obtained ; these compounds are decomposed by wateror acids, and their infrared spectra suggest that they contain N=B=N3-ions.65The hypoborate NaOBH,, which Stock reported to be formed by theaction of diborane on aqueous alkali, appears to have consisted mainly ofthe borohydride.s6 Hydrated sodium peroxoborate has been shown to con-tain two peroxo-bridges per anion, and its formula should be writtenNa2[B2( %(OH)41,6H20-67Aluminium. The preparation of lithium and sodium aluminiumhydrides from metal hydrides, aluminium, and hydrogen in tetrahydrofuranhas been described, and the properties and uses of these compounds havebeen reviewed.68 Lithium aluminium hydride in benzene or ether reacts571.G. Ryss and D. B. Donskaya, Zhur. neorg. Khim., 1960, 5 , 2251 [1090].68H. D. Fischer, W. J. Lehmann, and I. Shapiro, J. Chem. Phys., 1961, 65,59 A. L. McCloskey, J. L. Boone, and R. J. Brotherton, J. Amer. Chem. SOC., 1961,6 o A. K. Holliday and A. G. Massey, J., 1961, 1893, 3348; J . Inorg. Nuclear Chem.,61 W. B. Fox and T. Wartik, J. Amer. Chem. SOC., 1961, 83, 498.62A. K. Holliday, M. E. Peach, and T. C. Waddington, Proc. Chem. SOC., 1961,63 K.M. Harman and A. B. Harmon, J. Amer. Chem. SOC., 1961, 83, 865; G. A.64R. H. Wentorf, J. Chem. Phys., 1961, 34, 809.65 J. Goubeau and W. Anselment, 2. anorg. Chem., 1961, 310, 248.6aR. E. Davis and J. A. Gottbrath, Chern. and Ind., 1961, 1961. .67A. Hansson, Acta Chem. Scand., 1961, 15, 934.'j8H. Clasen, Angew. Chem., 1961, 73, 322.1166.83, 1766.1961, 18, 108.220.Olbh and W. S. Tolgyesi, J. Org. Chem., 1961, 26, 231986 INORGANIC CHEMISTRYwith bromine or iodine and with hydrogen iodide according to the equa-tions 692LiAlH, + 4X2 + LiA12X, + LiX + 4H2BLiAlH, + 8HI + LiAl,I, + LiH + SH,.Indications of the existence in benzene solution of 2 : 1 complexes of tertiaryamines and aluminium hydride have been obtainede70 The latter com-pound reacts with isopropyl borate according to the equation4A1H3 + 3B(OR), -+ A1H3,3BH,,3Al(OR),.The product is a reducing agent comparable in power to aluminium boro-hydride (of which it may well be the aluminium isopropoxide adduct) andcan be used in a wide range of organic solvents.71It has been pointed out that the Raman spectra of Al,Me,Cl, andAI,Me,Cl,, which have been written with methyl bridges, are also compatiblewith the formulations Me,Al+ AlC1,- and Me2Al+ Me,AlC12- ; the equivalenceof all the methyl groups in these compounds, which is apparent in the nuclearmagnetic resonance spectra, could then arise by chlorine exchange.72Amines react with alkylaluminiums or alkylaluminium chlorides, giving1 : 1 adducts; when these are pyrolysed, intermolecuIar condensation occurswith the formation of alkanes and A1-N bridged polymers.73 Organomercuryand organolithium compounds have been used to prepare alkyl and vinylderivatives from lithium aluminium hydride [e.g., LiAl( CH=CH,),], amineadducts of aluminium hydride (e.g., Bu,Al,NMe,), and several other com-p0unds.7~ Dialliylamino-derivatives of aluminium have been made by thereactions 75AlH,,NR, + 3HNR’, + Al(NR’,), $.3H2 + NR,andCryoscopy in benzene shows that most of them are associated in this solvent.Boron trichloride decomposes the compounds, e.g.,2BCl, + (Me,N),Al-+ 2Me,N*BCl2 + Me,N*AlCl,.The cyclopentadienyl compound (C,H,)AlEt, has been prepared fromdiethylaluminium chloride and cyclopentadienylpotassium ; it reacts withtitanium(m) chloride to form (C,H,),TiCl,*AlEf,.76The compounds MRAlCl,, where M = Li, Nay or K and R = Me or Et,have been obtained by heating alkali-metal chlorides and alkylaluminium&chlorides; they are solids stable up to 300°, but they react with atmo-spheric oxygen, alcohols, or ethers. 77Al(NR’,), + AlCl, -+ Al(KR’,),Cl + Al(NR’,)Cl,.69F. Klanberg and H. W. Kohlschiitter, Ber., 1961, 94, 781.70R. K. Ruff and M. F. Hawthorne, J . Amer. Chem. SOC., 1961, 83, 535.71 J. Kollonitsch, Nature, 1961, 189, 1005.V2R. E. Glick and A. Zwickel, J . Inorg. Nuclear Chem., 1961, 16, 149.7 3 A. W. Laubengayer, J. D. Smith, and G. G. Ehrlich, J . Amer. Chem. SOC., 1961,83, 542.74 J. K. Ruff, J . Amer. Chem. SOC., 1961, 83, 1798; F.M. Peters and B. Bartocha,Chem. and I n d . , 1961, 1271; B. Bartocha, A. J. Bilbo, D. E. Bublitz, and M. Y. Gray,2. Naturforsch., 1961, 16b, 357; B. Bartocha and A. J. Bilbo, J . Amer. Chem. SOC.,1961, 83, 2202.76 J. K. Ruff, J . Amer. Chem. SOC., 1961, 83, 2835.7sU. Giannini and S. Cesca, Gazzetta, 1961, 91, 597.77G. J. Sleddon, Chem. and I d . , 1961, 1492SHARPE: TYPICAL ELEMENTS 8'7An X-ray study of the complex Al2Br6,C6H6 suggests that the com-ponents are held together only by van der Waals bonding, though the pos-sibility of charge-transfer interaction between the n-electrons of the ringand the bridge bromine atoms of the inorganic moiety cannot be entirelyexcluded. 78Gallium, indium, and thallium. When gallium dissolves in 1 hf-per-chloric acid, Ga+ appears to be formed as an intermediate species.79Trivinylgallium, a liquid which is hydrolysed by water or acid and whichpolymerises above 70", is obtained by the action of divinylmercury on galliumat room temperature.Group IV.--Carbon.The reduction of mercuric salts in aqueous solutionby carbon monoxide appears to proceed by the mechanism(fast)(fast)-Hg2+OH2 + CO + [-Hg-CO,H]+ + H+ (Slow)[-Hg-CO,H]+ -+ Hg + CO, + H+Hg + Hg2+ -+ HgZ2+Carbon monoxide also reduces permanganate, and the reaction is stronglycatalysed by Ag+ or Hg2+ (but not by Cu2+, Fe3+, Cd2+, or T13+); forcatalysis by mercuric ion, intermediates such as [-HgCO,MnO,] aresuggested.81The C0,- ion has been shown from a study of its electron spin resonancespectrum to be bent, the LOCO being about 134".s2 The compound oftriethylphosphine and carbon disulphide is a zwitterion Et,P +-CSS -.83When finely divided sodium hydrogen carbonate dispersed in ether is cooledto -30" and treated with hydrogen chloride in ether, no evolution of gastakes place, and by cooling to -78" snow-white crystals of H,CO,,Et,Ocan be isolated.The solution is stable at -30" but the crystals decomposerapidly a t - 10". The dietherate of thiocarbonic acid, an orange-colouredoil, is similarly obtained by decomposing a solution of barium thiocarbonatein ether with gaseous hydrogen chloride.88Reviews have been given of silanes and their derivative^,^^the synthesis and reactions of organo-silicon, -germanium, and -tin com-pounds, 86 and compounds containing Si-N bonds.87Active silicon is obtained by the action of one mol.of chlorine on calciumdisilicide suspended in carbon tetrachloride a t 2 0 4 0 " ; by the furtheraction of another mol. of chlorine the red subchloride Sic1 is produced.Both compounds react violently with water or methanol.88 Silylpotas-sium, KSiH,, is prepared from silane and potassium in 1,2-dimethoxyefhaneSilicon.D. Eley, J. H. Taylor, and S. C. Wallwork, J., 1961, 3867.79K. Schug and A. Sadowski, J. Arner. Chem. SOC., 1961, 83, 3538.J. P. Oliver and L. G. Stevem, J . Inorg. Nuclear Chem., 1961, 19, 378.slA. C. Harkness and J. Halpern, J . Amer. Chem. SOC., 1961, 83, 1258.82D. W. Ovenall and D. H. Whiffen, Mol. Phys., 1961, 4, 135.a3 T.N. Margulis and D. H. Templeton, J . Amer. Chem. SOC., 1961, 83, 995.84 A. G. Galinos and A. A. Carotti, J . Amer. Chem. SOC., 1961,83,752; A. G. Galinos85A. G. MacDiarmid, Adv. Inorg. Chem. and Radiochem., 1961, 3, 207.8sA. D. Petrov and V. F. Mironov, Angew. Chern., 1961, 73, 59.R. Fessenden and J. S. Fessenden, Chem. Rev., 1961, 61, 361.8 e E . Bonitz, Ber, 1961, 94, 220.Bull. SOC. chirn. France, 1961, 141588 IN 0 RG ANIC C H E Ril: I S T R Yor from potassium and disilane; it reacts with water, hydrogen chloride,diborane, and methyl chloride. No disilane is formed in its reaction withsilyl bromide. If the expected adduct K+H,B*SiH,- is formed in thereaction with diborane, it disproportionates, and potassium borohydride isproduced.89 The preparation of silyl and arylsilyl halides by reactionssuch asPhSiH, + HX -3 PhH + SiH,XPhSiH,X + HX + PhH + SiH,X,(X = Br or I)(X = C1 or Br)(X = Br or I)has now been described in detail.g0 Mixed halides, e.g.SiH,BrI, dispro-portionate readily.Catenated silicon compounds which have recently been prepared includeC1SiPh,*SiPh2*SiPh2*SiPh2Cl (from cyclic Si,Ph8 and mercuric chloride), andMe,Si*SiMe,*SiMe,*SiMe, (from sodium-potassium alloy and Me,Si*SiMe,Cl). 91The pyrolysis of tetramethylsilane results in the formation of thecompound Me,Si:CH*SiMe,, the first well-defined compound reported tocontain a silicon-carbon double bond. Bromine is added, formingMe,SiBr*CHBr*SiMe, ; hydrogen bromide reacts to form Me,SiBr*CH,SiMe,.92Disiloxane does not form stable adducts with boron trifluoride; even at-78" cleavage of the Si-0 bond occurs:Ph,SiH, + HX+ PhH + PhSiH,S(SiH,),O + BF, + SiH,F + SiH,*OBF,.Siloxyboron dichloride is stable at room temperature, but the difluoride dis-proportionates into silyl fluoride, boron trifluoride, and boron trioxide.Disilthian does not react with boron trifluoride at all, sulphur attached totwo silicon atoms showing, as in other compounds, no electron-donatingproper ties.The liquid dimethylsiloxane heptamer has been shown to be very stabletowards attack by active nitrogen, but a slow reaction leading to the pro-duction of hydrogen cyanide and ammonia has been dete~ted.9~ Whensilane reacts with methanol at room temperature, a mixture of methoxy-silanes results, but the monosubstituted silane is not among them.Thiscompound can, however, be made from methanol and the trimethylamineadduct of silyl iodide; towards diborane it is found to be, as would be ex-pected, a weaker Lewis base than dimethyl ether.95 The compounds(Me,SiSe),, (Me,SiSe),, (Me,GeSe),, and (Me,SnSe), have been obtained bythe general reactionMe2MCl, + Na,Se + Me,MSe + 2NaClin dry benzene ; trimethylchlorosilane reacts similarly to give hexamethyl-disilyl selenide, and triphenylchlorostannane gives the analogous tin com-8sM. A. Ring and D. M. Ritter, J . Amer. Chem. SOC., 1961, 83, 802.G. Fritz and D. Kummer, Ber., 19b1, 94, 1143; 2. anorg. Chem., 1961, 310, 327.slH. Gilman and A. W. P. Jarvie, Chem.and In&., 1960, 965; G. R. Wilson andOZG. Fritz and J. Grobe, 2. anorg. Chem., 1961, 311, 325.ssM. Onyszchuk, Canad. J . Chem., 1961, 39, 808.J. L. Weininger, J . Amer. Chem. SOC., 1961, 83, 3388.OsB. Sternbach and A. G. MacDiarmid, J . Amer. Chem. SOC., 1961, 83, 3384.A. G. Smith, J . Org. Chem., 1961, 26, 557SHARPE: TYPICAL ELEMENTS 89Salts containing the triphenylsilyltriphenylborate anion or its pound.96germanium analogue are obtained by the reactionPh,MLi + Ph,B +- Li(Ph,M*BPh,).Both anions are very readily hydrolysed, but they are stable enough inmethanolic solution for precipitations with large inorganic and organiccations to be carriedTrends in the strengths of the compounds Ph,M*OH as hydrogen-bonddonors and acceptors suggest that dative n-bonding from oxygen to M isstrong when M is silicon, weaker when M is germanium, and negligible whenM is carbon, tin, or lead.98Trimethylgermanyl trimethylsilyl sulphate is obtained by the reactions(Me,GeO),SO, + ZLiO*SiMe, --+ Li,SO, + 2Me,Ge*O*SiMe,The chromate, selenate, and arsenate can be prepared similarly.The sd-phate disproportionates when it is heated; the chromate explodes.99 Themixed oxide, which has also been made by the reaction Me,GeCl +LiO-SiMe, --j. LiCl + Me,Ge*O*SiMe,, is cleaved by aluminium chlorideaccording to the equation looMe,Ge.O-SiMe, + AlCl, -+ Me,GeCl + Me,Si*O*AlCl,.Trimethylsilyl esters of the type R*CO,SiMe, react with trimethylsilyl-amines to form hexamethyldisiloxane and an organic amide, and the reac-tion is catalysed by acids.101Dimethylaminobromosilanes are obtained by the action of dimethyl-amine on silicon tetrabromide ; the corresponding fluorosilanes may be madefrom dimethylainine and chloro- or bromo-fluorosilanes, the latter com-pounds being obtained by cleavage of dimethylaminohalogenosilanes withboron trifluoride.lo2Silyl-substituted alkali-metal amides can be made from bistrialkylsilyl-amines and phenyl-lithium, sodamide, or metallic potassium; they aresoluble in nonpolar organic solvents, form adducts with ethers and withpyridine, and readily react with chlorosilanes, e.g.(Me,Si),NLi + ClSiMe, + (Me,Si),N.SiMe, + LiClThe tris-silylamines so obtained are waxy solids of low melting point whichcan be distilled in vucuo without decomposition and are resistant to hydro-lysis.lo3 Several silyl-substituted hydrazines have been made by thereactionsR,Si*NH*NH.SiR, + LiPh + R’,SiCl + (R’,Si)(R,Si)NNH*SiR, + LiCl + PhHPh,SiCl, + 4RR’N.NH2 +- B(RR’N*NH,)Cl + RR’N*NH*SiPh,-NH*NRR’.Me,Ge*O*SiMe, + SO, -+ Me,Ge*O*SO,*O*SiMe,.__ - _ _ ~ _______~~BsM.Schmidt and H. Ruf, Angew. Chem., 1961, 73, 64.O7 D. Seyferth, G. Raab, and S. 0. Grim, J . Org. Chem., 1961, 26, 3034.seR. West, R. H. Baney, and D. L. Powell, J . Amer. Chem. SOC., 1960, 82, 6269.OBH. Schmidbaur and M. Schmidt, Ber., 1961, 94, 2137, 2451.looH. Schmidbaur and M. Schmidt, Ber., 1961, 94, 1138, 1349.lolR. M. Pike, Rec. Trav. chim., 1961, 80, 819.loaG. Schott and G. Gastmeier, 2. Chem., 1961, 1, 123; H.Grosse-Ruyken andlo3U. Wannagat and H. Niederpriim, Ber., 1961, 94, 1540; Z. anorg. Chem., 1961,R. Kleeaaat, 2. anorg. Chem., 1961, 308, 123.308, 33790 INORGANIC CHEMISTRYIn the latter case R = R' = Me or R = H, R' = Ph, and the products arevery sensitive to decomposition by water and readily undergo condensationinto cyclic compounds.104 Trimethylchlorosilane reacts with urea at 300"to form trimet hylsil yl is0 cyanat e .I05Many examples of the cleavage of silicon-nitrogen bonds by boron, alu-minium, or phosphorus trihalides have been reported, e.g.106(Me,Si),NH + BF, --+ Me,SiF + Me,Si-NH*BF,Me,Si*NMe, + BC1, -+ Me,SiCl + Me,N*BCl,.The imide Si,(NH), is the only silicon-containing product of the decom-position of disilicon hexachloride by ammonia; it is hydrolysed by waterto ammonia, hydrogen, and silica, and undergoes a complex thermaldecomposition into ammonia and a mononitride.lo7 Disilylcyanamide,(SiH,),N.CN, which has been made by the action of silyl iodide on silvercyanamide, forms an unstable adduct with boron trifluoride, and is decom-posed into diaminomethylene &chloride andmonochlorosilane by hydrogen chloride.108 The I I first four-membered cyclic silicon - nitrogenMe3Si'N-SiMe2 (2) systeni (2) has been obtained by the actionof dimethyldichlorosilane on the dilithiumderivative of the amine Me3Si*NH*SiiMe,*NH-SiMe3.109Silicon tetrafluoride reacts with silicon disulphide at 1000" to form thecompound F,Si*S,*SiF,, which on cooling slowly reverts to the startingmaterials.l o Silicon, tin, or boron halides usually form addition compoundswith sulphoxides, but occasionally a chloro-substituted sulphide results,e.g.lll2Me,SO + SiCI, -+ 2MeS.CH2C1 + SiO, + 2HC1.The preparation of the chloride Si5Cll, by the action of trimethylamine ondisilicon hexachloride has been described in detail, and it is suggested thatthe compound may have the neopentyl structure. 112 Cyclic chlorosil-oxanes [SiOCl,], with n = 3, 4, or 5, and lower open-chain compoundsSi,O,,-,,CI,,,+,, are obtained from the interaction of oxygen and silicontetrachloride at 1000 O . 1 1 3 Silicon tetrachloride in ether reacts with silvernitrate in acetonitrile at -40" to yield silver chloride and a solution-fromwhich pyridine precipitates the compound Si(N03)4,2py.114Further work on the mechanism of substitution in silicon compoundshas been reported, and it has been shown that substitution at an asymmetricsilicon atom may be accompanied by inversion or retention of codigura-104U.Wannagat and H. Niederpriim, 2. anorg. Chem., 1961, 310, 32; 1961, 311,105 J. Goubeau and D. Paulin, Ber., 1960, 93, 1111.106 M. Becke-Goehring and H. Krill, Ber., 1961,94, 1059; H. Noth, 2. Naturfwsch.,107 M. Billy, Bull. SOC. chim. Prance, 1961, 1550.lo*E. A. V. Ebsworth and M. J. Mays, J., 1961, 4879.lo9 W. Fink, Angew. Chem., 1961, 73, 736.1lOV. Gutmann, P. Heilmayer, and K. Utvary, Monatsh., 1961, 92, 942.111M. F. Lappert and J. K. Smith, J., 1961, 3224.112 A. Kaczmarczyk, M. Millard, and G.Urry, J . Inorg. Nuclear Chem., 1961,17, 188.1laD. W. S. Chambers and C. J. Wilkins, J., 1960, 5088.l141. R. Beattie and G. J. Leigh, J., 1961, 4249.Me2S i - N.S i Me.3270.1961, 16b, 618SHARPE: TYPICAL ELEMENTS 91tion.l15 Evidence has also been presented which suggests that the reactionMe,SiCH,*CH,*Cl + RON + Me,Si*OR + C,H, + HCl(where R = H or Et) takes place by a limiting siliconium-ion mechanism.116Yields of germane and stannane in the boro-hydride reduction of germanium and tin compounds can be improved some-what by dropping an alkaline solution of sodium borohydride and germaniteor stannite into dilute acid; however, it should be noted that no silane isobtained by a similar reaction with sodium ~i1icate.l~' Passage of mono-germane a t 0.5 atm.and -78" through a silent electric discharge resultsin the formation of hydrides containing up to eight atoms of germanium.l18Germanium difluoride, a white solid melting at 110", is obtained byreduction of the tetrafluoride with the element. It is immediately hydro-lysed by water, and is converted by selenium tetrafluoride into the com-pound GeF4,2SeF,.119 Monofluorogermane has been made by the action ofargentous fluoride on the bromo-compound; it forms a 1 : 2 adduct withammonia, but the product is unstable at 25" and is converted into ammoniaand a 1 : 1 adduct for which the structure GeH,*NH,+ F- is suggested.Monofluorogermane readily disproportionates into the difluoro-compoundand germane.120 Hexachlorogermanates are formed only by rubidium,czsium, and large organic cations ;121 several complexes of germanium tetra-chloride and heterocyclic bases have been described.122Trimethylchlorogermane can be obtained by the action of methyl-lithium or methylmagnesium iodide on the dimethyldichloro-compound,123or by the interaction of tetramethylgermane, hydrogen chloride, and alu-minium ~hloride.12~ It reacts with silver carbonate to form silver chloride,carbon dioxide, and hexamethyldigermoxane, (Me,Ge),O, which does notform a stable complex with boron trifluoride but undergoes cleavage accord-ing to the equationGermanium, tin, und lead.3(Me,Ge),O + ZBF, -+ 6Me,GeF 4 B,O,.Attempts to make digermoxane, (GeH,),O, have been unsuccessful. Meth-oxytrimethylgermane, which is made by the reactionMe,GeBr + NaOMe + Me,GeOMe + NaBr,does, however, form a stable 1 : 1 adduct with boron trifluoride; evidentlyd, - p , bonding, if it occurs here, does not appreciably alter the donorpr0perties.12~ Trimethylchlorogermane reacts with silver vanadate, chrom-ate, selenate, or perrhenate to form esters; the same compounds can alsol15L.H. Sornmer, C. L. Frye, M. C. Musolf, G. A. Parker, P. G. Rodewald, K. Wll6L. H. Sommer and G. A. Baughtman, J . Amer. Chem. SOC., 1961, 83, 3346.11' W. L. Jolly, J . Amer. Chern. Soc., 1961, 83, 335.11* J. E. Drake and W. L. Jolly, Proc. Chem. SOC., 1961, 379.lloN. Bartlett and K. C. Yu, Canad. J . Chem., 1961, 39, 80.laoT. N. Srivastava and M. Onyszchuk, Proc. Chem. Soc., 1961, 205.lalV.V. Udovenko and Y. A. Fialkov, Zhur. nemg. Khim., 1960, 5, 1502 [728].laaV. G. Lebedev and V. G. Tronev, Zhur. newg. Khim., 1960, 5, 1725 [837].1aJM. Schmidt and I. Ruidisch, 2. anorg. Chem., 1961, 311, 331.114 J. E. GriEths and M. Onyszchuk, Canad. J . Chem., 1961, 39, 339.Michael, Y. Okaya, and R. Pepinsky, J . Amer. Chem. Soc., 1961, 83, 221292 INORGANIC CHEMISTRYbe made by the action of the appropriate oxide on hexamethyldi-germoxane.Dichlorogermanium phthalocyanine has been made from the tetra-chloride and phthalocyanine in quinoline a t 240°, and by replacement of thechlorine atoms the dihydroxy-compound has been prepared.126The Raman and infrared spectra of the trimethyltin halides show thatonly the fluoride has an ionic lattice; there is a planar distribution of valen-cies round the tin in the Me3Sn+ cation.The other halides are associatedby means of halogen bridging.12' The sodium salt NaSnMe, reacts withtrimethylborane-ammonia in liquid ammonia, forming hexamethyldi-stannane. This compound is catalytically decomposed by boron tduoridein ether, giving methyltin polymers and tetramethyltin; the latter compoundthen reacts with the boron trifluoride, forming methylboron difiuoride andtrimethyltin tetrafluoroborate. The decomposition of hexamethyldistan-nane, like that of trimethylstannane, is also catalysed by diborane.128When triphenyltin chloride reacts with magnesium in tetrahydrofuran, ethylbromide being added as an initiator, the compound (Ph,Sn),Mg is formed(hexaphenyldistannane is an intermediate) ; .ammonium chloride solutionhydrolyses the compound to triphenylstannane and magnesium hydrox-ide.129 Tri-n-butylstannyl-lithium reacts with trimethylchlorosilane andwith carbon dioxide as if it contained butyl-lithium in equilibrium withdibutyltin.Triphenylstannylsodium, which can be made from sodiumnaphthenide and tetraphenyltin or triphenyltin bromide, reacts normallywith ethyl bromide but as a reducing agent with benzophenone, oxygen,carbon dioxide, and sulphur dioxide. The interaction of trimethyl-stannylsodium and chloroform gives not Me,Sn*CH:CHBnMe,, as reportedearlier, but Me3Sn.CH2*SnMe3. l 3 l The preparation of some new modifica-tions, and several new reactions, of diphenyltin have been r e p ~ r t e d , l ~ ~ andit has been shown that di-n-butylchlorostannane can be made by interactionof the dihydride and the dichloro-compound at room temperature.133Several compounds containing Sn-0-Si linkages have been obtained bythe co-hydrolysis of a dialkyltin dichloride and trimethylchlorosilane or byreactions of the typeMe&-OLi + Me3SnC1 + LiCl + Me,Si*O.SnMe,.The second method can be modified for use in the preparation of Pb-O-Sicompounds ; both the tin and the lead compound show considerable thermalstability, but the vapour of the lead compound explodes with oxygen attemperatures above 150°.134125M.Schmidt, H. Schmidbaur, I. Ruidisch, and P. Bornmann, Angew. Chem.,1961, 73, 408; M. Schmidt, I. Ruidisch, and H. Schmidbaur, Ber., 1961, 94, 2451.126 R.D. Joyner and M. E. Kenney, J . Amer. Chem. SOC., 1960, 82, 5790.1 2 7 H . Kriegsmann and S. Pischtschan, 2. anorg. Chem., 1961, 308, 212.128 A. B. Burg and J. R. Spielman, J . Amer. Chem. SOC., 1961, 83, 2667.129 C. Tamborski and E. J. Soloski, J . Amer. Chem. SOC., 1961, 83, 3734.130D. Blake, G. E. Coates, and J. M. Tate, J., 1961, 618.131 H. D. Kaesz, J . Amer. Chem. Soc., 1961, 83, 1514.1*2H. G. Kuivila, A. K. Sawyer, and A. G. Armour, J . Org. Chern., 1961, 26, 1426;133 A. K. Sawyer and H. G. Kuivila, Chem. and Ind., 1961, 260.134 R. Okawara, D. G. White, K. Fujitani, and H. Sato, J . Amer. Chem. SOC., 1961,H. G. Kuivila and E. R. Jakusik, ibid., p. 1430.83, 1342; H. Schmidbaur and M. Schmidt, ibid., p.2963SHARPE: TYPICAL ELEMENTS 93The nuclear magnetic resonance spectra of mixtures of stannic chloride,bromide, and iodide show that all possible mixed halides are pre~ent.1~5The infrared spectra of the 2 : 1 complexes of esters and stannic chlorideshow the acyl-oxygen atom to be the donor.136Further work on perfluoroalkyl and perfluorovinyl derivatives has beendescribed ;I37 the ease of cleavage of organic groups from tin by protonic acidsis perfluorovinyl M phenyl > vinyl > alkyl > perfluoroalkyl. Organotinhalides can be perfluorovinylated by addition of bromotrifluoroethylene andthe organotin compound in tetrahydrofuran to magnesium turnings a t-10"; cleavage of the perfluorovinyl group from the products can beeEected by alcohol, acetic acid, hydrogen bromide, iodine, or sodium eth-The oxychloride, SnOCl,, can be made by the interaction of stannicchloride and, chlorine monoxide; it is a very hygroscopic solid which formsaddition compounds with phosphorus oxychloride and with pyridine.139 AnX-ray examination of the complex K,SnC1,,H20 shows that it contains C1-and pyramidal SnC1,- i0ns.1~0 The compounds formerly reported as tetra-alkyldihalogenodistannanes and made by the action of amines on dialkyltindihalides are, in fact, complexes of dialkyltin dihalides and dialkyltinoxides.141 It has been shown that the composition of " stannous hydroxide "is best represented by the formula Sn50,(OH)4; it is dehydrated in onestage at temperatures above 120" to give an orange modification ofstannous 0xide.142 Of the various basic stannous nitrates reported, onlySn3(OH)4(N03)2 can be obtained in a pure state from aqueous solutions, andit is interesting to note that this substance is a high exp10sive.l~~ A basicstannous phosphate Sn,(PO,),(OH),,H,O has been shown to be formed inthe reaction between some stannous salts and hydro~yapatite.1~4Di- and tri-alkylplumbanes can be made by reduction of the correspond-ing chlorides with potassium borohydride in liquid ammonia or lithium alu-minium hydride in dimethyl ether. Trimethylplumbane adds ethylene toform ethyltrimethylplumbane, and ammonia to form the green compoundNH4PbMe,, which decomposes via the red salt NH4Pb,Me5 into lead, tetra-methylplumbane, methane, and hydrogen, and reacts with trimethylchloro-plumbane in liquid ammonia to give he~amethyldiplumbane.~~~ The infra-red spectra of trimethyl-lead carboxylates suggest that these compoundscontain Me3Pb+ ions, with a planar configuration round the lead.146135 J.J. Burke and P. C. Lauterbur, J . Amer. Chem. SOC., 1961, 83, 326.1361\1. F. Lappert, J., 1961, 817.13' H. D. Kaesz, J. R. Phillips, and F. G. A. Stone, J . Amer. Chenz. SOC., 1960, 82,6228; H. D. Kaesz, S. L. Stafford, and F. G. A. Stone, ibid., p. 6232; R. D. Chambers,H. C. Clark, and C. J. Wilkins, Canad. J . Chem., 1961, 39, 131.lSsD. Seyferth, G. Raab, and K. A. Brlindle, J . Org. Chem., 1961, 26, 2934.13@K. Dehnicke, 2. anorg. Chem., 1961, 308, 72.laOD. Grdenic and B. Kamenar, Proc. Chem.SOC., 1961, 304.141 D. L. Alleston and A. G. Davies, Chem. and I d . , 1961, 949.142 J. D. Donaldson and W. Moser, J., 1961, 835; J. D. Donaldson, W. Moser, and143 J. D. Donaldson and W. Moser, J., 1961, 1996.R. Collins, W. Nebergall, and H. Langer, J . Amer. Chem. Soc., 1961, 83, 3725.146 W. E. Becker and S. E. Cook, J . Amer. Chem. SOC., 1960, 83, 6264; R. Duffy14"R. Okawara and H. Sato, J . Inorg. Nuclear Chem., 1961, 16, 204.W. B. Simpson, J., 1961, 839.and A. K. Holliday, J., 1961, 167994 INORGANIC CHEMISTRYTriphenyl-lead azide has been made by the action of hydrazoic acid onthe hydroxide in ethanol-chloroform, and shows no explosive pr0perties.1~7Lead chloride or bromide reacts rapidly with phenyl-lithium or phenyl- ormesityl-magnesium bromide in tetrahydrofuran at -40 O ; the deeplycoloured solutions which result involve the equilibria 148PbAr, + ArLi + Ar,PbLior PbAr, + ArMgBr + Ar,PbJIgBr.Group V.-Nitrogen. When ammonium fluoride is subjected to 3800 atm.pressure at room temperature? a cubic form is produced with a diminutionin volume of about 28%; no work on the structure of this phase has yet beenreported, but the result strongly suggests the formation of a sodium orcssium chloride form.149 A study of the NH,HF,-HF system has con-firmed earlier reports of the existence of NH,H,F4 and NH4H,F,, but notNitrogen trifluoride reacts with trifluoroacetonitrile when the two arepassed over czesium fluoride at 520°, forming the compounds CF,NF,,(CF,),NF, CF,*NCF,, and ( CNF),.With perfluoropropene over the samecatalyst at 320", very little C3F8 is formed, and the major products are(CF,),CF*CF(CF,),, (CF,),CF*NF,, and (CF3),C:NF.151 More work on thefluoride N,F4 has been described, and it has been shown to exist in equi-librium with NF,* radicals? these being responsible for the colour of theordinary p r 0 d ~ c t . l ~ ~ Under the influence of ultraviolet light it convertschlorine into chlorodifluoramine, ClNF,, hexaphenylethane into Ph,C*NF2,a-diketones into NN-difluoro-amides, and alkyl iodides into NN-difluoro-alk~1amines.l~~ The interesting debate on the structure of the higher-boiling isomer of N2F2 has been continued; all that can be said is that a firmdecision between cis-FNNF and F2N=N is not yet possible.154 The proper-ties of the thiofluorides NSF and NSF, have now been described in detail, andthe preparation of monomeric NSCl by the action of chlorine on the mono-fluoro-compound has been r e ~ 0 r t e d .l ~ ~The yellow solid formed by addition of excess of sodium nitrite to a solu-tion of sodium in liquid ammonia is mainly Na,N,O,, but its electron-spinresonance spectrum confirms that Na,NO, is a minor ~0nstituent.l~~ Nitricacid is extracted from 6--16~-aqueous solution into benzene or toluene asthe hemihydrate, for which a structure intermediate between (3) and (4)is suggested.15' Salts and esters of the acid P(O)(OH),*NN*P(O)(OH), haveof147E. Lieber and F. M. Keane, Chem. and Ind., 1961, 747.14*F. Glockling, K. Horton, and D.Kingston, J . , 1961, 4405.lasR. Stevenson, J . Chem. Phys., 1961, 34, 346.150R. D. Euler and E. F. Westrum, J . Phys. Chem., 1961, 65, 1291.R. D. Dresdner, F. N. Tlumac, and J. A. Young, J . Amer. Chern. Soc., 1960, 82,152F. A. Johnston and C. B. Colburn, J . Amer. Chem SOC., 1961, 83, 3043.163 R. C. Petry and J. P. Freeman, J. Amer. Chem. SOC., 1961,83,3912; J. W. Frazer,16*R. Ettinger, F. A. Johnson, and C. B. Colburn, J . Chem. Phys., 1961, 34, 2187;1650. Glemser and H. Richert, 2. anorg. Chem., 1960, 307, 313, 328; 0. Glemser166 H. C. Clark, A. Horsfield, and M. C. R. Symons, J . , 1961, 7.157 C. J. Hardy, B. F. Greenfield, and D. Scargill, J., 1961, 90.6831.J. Inorg. Nuclear Chem., 1961, 16, 63.R. H. Sanborn, ibid., p. 2188.and H.Perl, NaturwisS., 1961, 48, 620SHARPE: TYPICAL ELEMENTS 95been obtained by oxidation of the corresponding derivatives of hydrazine,e.g. K,N,H,P,O,, with hydrogen peroxide, mercuric oxide, or N-bromosuc-cinimide; the potassium salt is decomposed by heat or by acids accordingto the equations 15*KZO,P.N:N.P03K, + N, + K4P20,2K203P.N:N*PO,Kz + 4KZO -+ N, + NzH, + 4KzHPO4.Di-imide, N2H2, previously postulated as an intermediate in certainoxidations of hydrazine, has been shown to possess a finite lifetime, and itsapplication to the reduction of organic compounds has been ~tudied.1~9The compound HCP has been obtained by passing phos-phine through a low-intensity rotating arc struck between graphite elec-trodes, and quenching the gaseous products at -196".It is a very reactivecolourless gas stable only at temperatures below its triple point (-1.24');it polymerises rapidly at -78" to a black solid, and combines with hydrogenchloride, yielding methyldichlorophosphine.160 Tetraphenylphosphoniurnborohydride has been made from the hydroxide (prepared by ion-exchange)and potassium borohydride ; its thermal decomposition gives benzene andPh3P*BH,.161 Attempts to make phosphine oxide, PH,O, by the action oflithium hydride or lithium aluminium hydride on phosphoryl chloride orbromide show that the compound is highly unstable, decomposing even at-115" to water and a polymeric monohydride of phosphorus.162 The rela-tive strengths of some alkylphosphines as bases towards trimethylboron havebeen compared, and the chemistry of methylenetriphenylphosphorane,Ph,P:CH,, has been studied extensively : l 6 3 the compound adds trimethyl-bromosilane to give [ Ph,P*CH,*SiMe,]Br and boron trifluoride to givePh,P +*CH,*BF3-. Tetramethyldiphosphine combines with ethylene below300", forming mostly Me,P*CH,*CH,*PMe,, which forms mono- and di-borane adducts ; tetramethyldiphosphine itself combines with diboraneforming H,B*PMe,*PMe,*BH,, which is converted by heat into (Me,P*BH,),,Phosphorus.15* H.Bock and G. Rudolph, Ber., 1961, 94, 1457.15# E. J. Corey, W. L. Mock, and D. J. Pasto, Tetrahedron Letters, 1961, No. 11,lsoT. E. Gier, J . Arner. Chem. SOC., 1961, 83, 1769.161€€. G. Heal, J . Inorg. Nuclear Chem., 1961, 16, 208.laa E. Wiberg and G. Miiller-Schiedmayer, 2.anorg. Chem., 1961, 308, 352.347; J . Amer. Chem. Xoc., 1961,83, 2957; E. E. van Tamelen, R. S. Dewey, M. F. Lease,and W. H. Pirkle, &bid., p. 4302.H. D. Krtesz and F. G. A. Stone, J . Amer. Chem. SOC., 1960, 82, 6213; D. Sey-ferth and S. 0. Grim, ibid., 1961, 83, 1610, 161396 INORGANIC CHEMISTRYwhere n = 3 or 4.16& The compounds P,(NMe2)4 and P,(NMe,), [i.e.,(Me,N) ,POP( NMe, ) *P(NMe, ) 2] are obtained when bisdimet hylaminochlor o -phosphine is treated with sodium, and many reactions of the former com-pound have been described. Bromine converts it into (Me,N),PBr, oxygenforms a diphosphine oxide, diborane yields (Me,N),( H,B)P*P( BH,) (NMe2)2,, and hydrogen chloride, which forms a salt at low temperature, cleavesthe P-P bond and gives dimethylammonium chloride and a mixture ofphosphorus chlorides.165The chemistry of the halides of phosphorus, arsenic, antimony, andbismuth has been reviewed. 166 Phosphorus tri- and penta-fluorides areboth obtained in high yield by the action of calcium fluoride on the corre-sponding chloride at 300--400". The trifluoride has negligible acceptorproperties, but itsreactions with alkali-metal fluorides (which lead to the for-mation of hexafluorophosphates and phosphorus) may involve tetrafluoro-phosphites of the type MPF, as intermediates. The pentafluoride, on theother hand, is a very good electron-acceptor, and forms complexes withamines, ethers, nitriles, and sulphoxides, and is a good catalyst for ionicpolymer is at ion^.^^^ Tetrasulphur tetranitride reacts with phosphorus tri-chloride to form compound NP,Cl, which as the solid and in nitrobenzeneappears to be PC14+ PNCl,-.lsg With silver cyanide and with methylaminethe trichloride gives the compounds P(CN), and P4(NMe)6, respectively;169the latter compound is probably an analogue of P406.The cyclic compounds(PCF,), and (PCF,), react easily and reversibly with trimethylphosphine ortrimethylamine to form Me,P*PCF, or Me,N*PCF, ; traces of trimethyl-phosphine thus catalyse the interconversion of tetramer and pentamer, buthigher (PCF,), polymers do not appear to be formed.170Much further work on the phosphorus oxychloride and related solventsystems has been reported 171 and interpreted in terms of chloride-ion trans-fer. Serious doubts on the validity of this interpretation have, however,been expressed, and it has recently been shown that anhydrous ferric chloridein triethyl phosphate forms a solution very similar t o that in phosphorusoxychloride, the equilibriaFeCl, + Y3P0 + [FeCl,OPY,] + [FeCl(y-,)(OPk',)(l+~)]~+ + xFeC1,-+ [Fe(OPY3),I3+ +- 3FeC1,-,where Y = C1 or OEt, describing both systems.This mechanism is con-164 A. B. Burg, J . Anzer. Chem. SOC., 1961, 83, 2226.16sH. Noth and H.-J. Vetter, Ber., 1961, 94, 1505.166D. S. Payne, Quart. Rev., 1961, 15, 173.167E. L. Muetterties, T. A. Bither, M. W. Farlow, and D. D. Coffman, J . Irwrg.Nuclear Chem., 1961, 16, 52.168 0. Glemser and E. Wyszomirski, Nuturwiss., 1961, 48, 25.169 J.Goubeau, H. Haeberle, and H. Ulmer, 2. anorg. Chem., 1961, 311, 110;R. R. Holmes, J . Amer. Chem. Soc., 1961, 83, 1334.170A. B. Burg and W. Mahler, J . Amer. Chem. SOC., 1961, 83, 2388.171M. Baaz, V. Gutmann, and L. Hubner, Monatsh., 1961, 92, 135, 272, 707; M.Baaz, V. Gutmann, M. Y. A. Talaat, and T. S. West, ibid., pp. 150,164,714; M. Baaz,V. Gutmann, and J. R. Masaguer, ibid., pp. 582, 590; V. Gutmann and F. Mairinger,{bid., p. 720; M. Baaz, V. Gutmann, and L. Hubner, J . Inorg. Nuclear Chem., 1961,18, 276.17aD. W. Meek and R. S. Drago, J . dmer. Chem. SOC., 1961, 83, 4322SHARPE: TYPICAL ELEMENTS 97sistent with X-ray, Raman, and infrared spectral work, and the status ofthe phosphorus oxychloride, and indeed other oxyhalide, solvent systems hasclearly been severely challenged.A rapid preparation of sodium hypophosphate decahydrate from redphosphorus and bleaching powder has been described, and evidence has beenpresented to show that the crude oxidation product contains the calciumsalt of a new acid H,P407; a study of vibrational spectra shows the P,O,4-and S,0G2- ions to be isostru~tural.~~~ The esters CF,*P(OMe), andCF,*PO,C,H, have been made from trifluoromethyldichlorophosphine andmethanol and ethylene glycol, respectively, higher polymers also beingformed in the latter reaction.Neither ester shows any tendency to re-arrange, but the free acid (obtained by the action of hydrogen bromide onthe ester) exists almost entirely as the dimer of CF,*PH(0)*OH.174Another review of the chemistry of the phosphonitrilic halide polymershas been p~blished.1~~ The conversion of the chlorides into fluorides bythe action of argentous fluoride, sodium fluoride, and potassium fluoro-sulphinate, KSO,F, hqs been further de~cribed;l'~ it has been shown thatwhen the last reagent is used a PFCl group is more susceptible to halogenexchange than a PCl, group.Further work has also been reported on thealcoholysis 177 and aminolysis 178 of the chlorides. Some alkoxy-compoundsrearrange to give N-alkyl derivatives when they are heated at 200°, e.g.(5)-+(6) 179The synthesis of some tris-alkyl and -aryl derivatives of the trimer has beendescribed : (PhClPN), from the products of the interaction of phenyltetra-chlorophosphorane and ammonium chlorideY1*0 and (MeClPN), by the reac-tion sequence 181MeMgBr HClN,P,Cl,(NMe,), I___+ N,P,Me,(NMe,), d N,P,Me,Cl, + Me,NH.The shape of the eight-membered P-N ring in the tetramers is now seen to173 W.G. Palmer, J . , 1961, 1079, 1552.17*A. B. Burg and J. E. Griffiths, J . Arner. Chenz. SOC., 1961, 83, 4333.1 7 5 1 . A. Gribova and U. Ban-yuan, Uspekhi Khim., 1961, 30, 3 [l].1'6 R. Ratz and C. Grundmann, J . Inorg. Nuclear Chem., 1961, 16, 60; T. Moeller,K. John, and F. Tsang, Chem. and Ind., 1961, 347; A. C. Chapman, D. H. Paine, H. T.Searle, D. R. Smith, and R. F. M. White, J . , 1961, 1768.177B. W. Fitzsimmons and R. A. Shaw, Chem. and Ind., 1961, 109.178 S. I<. Ray and R. A. Shaw, J., 1961, 872; K. John, T. Moeller, and L.F. Audrieth,J . Amer. Chem. SOC., 1961, 83, 2608; S. G. Kokalis, K. John, T. Moeller, and L. F.Audrieth, J . Inorg. Nuclear Chem., 1961, 19, 191.I;leB. W. Fitzsimmons and R. A. Shaw, Proc. Chem. SOC., 1961, 258.leoF. S. Humiec and I. I. Bezman, J . Amer. Chem. SOC., 1961, 83, 2210.la1 G. Tesi and P. J. Slota, Proc. Chem. SOC. 1960 404.98 INORGANIC CHEMISTRYdepend on the nature of the substituents, being planar in (PNF,), andpuckered in (PNCl,), and [PN(NMe,),],.182The compound Cl,P:N*P(O)Cl, is obtained by the interaction of phos-phorus trichloride and dinitrogen tetroxide or phosphoric amides and pbos-phorus pentachloride or hydroxylammonium salts and phosphorus tri- orpenta-chloride. From the thioamide PS(NH,), and the pentachloride thecompound Cl,P(N:PCl,), results.Both acid chlorides are extremely reac-tive. 183 When methylammonium chloride is heated with phosphorus penta-chloride in tetrachloroethane the compound (MeWPCl,), is formed ; infraredspectroscopy suggests that this contains a four-membered planar ring inwhich the nitrogen and phosphorus atoms are, severally, positively andnegatively charged. lS4Tetraphosphorus triselenide reacts with liquid ammonia to form(NH4),[P4Se,(NH,),], thermally degraded successively into (NH,),(P,Se3NH),(NH,)(P,Se,NH,), and P,Se,.ls5Arsenic, antimony, and bismuth. The arsonium ion has been identifiedby its infrared spectrum in the products of the interaction of arsine andhydrogen chloride, bromide, or iodide at low temperature. No similarevidence for the existence of the stibonium ion was found.186 Conducti-metric titration of a solution of sodium in liquid ammonia with arsine orstibine shows that the salts MHNa, and MH,Na are formed; phosphine givesonly PH,Na.Alkali-metal derivatives of diphenylarsine have beenobtained from the metals and diphenylarsine in dioxan; their reactions withiodine and trimethylchlorosilane give the compounds Ph,As-AsPh, andPh,As*SiMe,, respectively. Trimethylfluorosilane reacts similarly with thepotassium derivative of arsine, forming (Me,Si),AsH and (Me,Si),As ; similarcompounds containing trimethylsilyl or trimethylstannyl groups bonded tophosphorus are obtained by analogous inethods.188 Arsenobenzene hasbeen shown to contain As,Ph, units, the arsenic atoms forming a six-membered ring in the << chair '' form.189In mixtures of hydrogen fluoride and antimony pentafluoride the ionsH2F+ and sbF,- are f0rmed.1~0 Arsenic trichloride reacts with dimethyl-amine to form the compound As,(NMe), analogous to the phosphorusderivative described ab0ve.1~1 The compound SbC1,+SbF6-, an isomer ofthe fluorination catalyst SbF3Cl2, has been prepared by the action of chlorineon antimony trifluoride.192 Esters of arsenic acid, readily obtained bylS2 G.J. Bullen., Proc. Chem. Xoc., 1960,425; H. McD. McGeachin and F. R. Tromans,J., 1961, 4777.183 1LI. Becke-Goehring, T. Mann, and H. D. Euler, Ber., 1961, 94, 193; 31. Becke-Goehring, A. Debo, E. Fluck, and W. Goetze, ibid., p. 1383.184 A.C. Chapman, W. S. Holmes, N. L. Paddock, and H. T. Searle, J., 1961, 1825.185H. Behrens and G. Haschka, Ber., 1961, 94, 1191.186 A. Heinemann, Naturwiss., 1961, 17, 568.1 8 7 H. J. Emelbus and K. MacKay, J., 1961, 2676.188K. Issleib and A. Tzschach, Angew. Chem., 1961, 73, 26; A. B. Bruker, L. D.189 S. E. Rasmussen and J. Danielsen, A4cta C'heru. Scand., 1960, 14, 1862; K.19oH. H. Hyman, L. A. Quartermain, &l. Kilpatriek. and J. J. Katz., J. Phys.191 H. Noth and H. J. Vetter, Naturuiss., 1961, 16, 553.192L. Kolditz and W. von der Leith, 2. anory. G'heitL., 1961, 310, 236.Balashova, and L. Z. Soborovskii, Doklady ,41;ad. Nauk S.S.S.R., 1960, 135, 843.Hedberg, E. W. Hughes, and J. Waser, Acta Cryst., 1961, 14, 369.Chem., 1961. 65, 123SHARPE : TYPIC-4L ELEMENTS 99oxidation of alkyl arsenites with bromine, react with hydrogen fluoride orarsenic trifluoride to yield esters of monofluoroarsenic acid ; these combinewith a further molecule of alcohol to give esters of formula l?As(OH)(OR),which dissociate in polar solvents, ions such as [As(OH)(OR),] + and[As( OH)(0R),Fz] - being formed.193 The compounds Ph,AsX, andPh,AsX,, where X = Br or I, are also good conductors in polar solvents, andthe structures Ph,AsX +X - and Ph,AsX+X,- have been suggested.lg4Several monomers and polymers containing Si-0-As and Sn-O-As link-ages have been made by methods of which the following illustrations arerepre~entative.1~3Ph3SiC1 + Ag,AsO, -+ (Ph,SiO),AsO4NH, + 2Ph,Si(OH), + 2PhAs1, + 4NHJ + PhAs([O*SiPh,*O],)AsPhMe,SnCl, + 2AsPhO(OH), -+ 2HC1 + SnMe,(O*AsPhO*OH),.The reduction of alkylbismuth chlorides or bromides by lithium alu-minium hydride at - 110 O in dimethyl ether leads to the formation of alkyl-bismuth hydrides.These substances slowly disproportionate at tempera-tures above -50" into trimet,hylbismuth and the unstable bismuthane, BiH,(extrapolated b.p. 17 ').I96Group V1.-A new fluoride of oxygen, 04F2, is obtained by the actionof an electrical discharge on a mixture of oxygen and fluorine at 60-77 O K ;it is a red-brown solid decomposing even at 90-110" K into trioxygendifluoride and oxygen.197An induced isotopic exchange of oxygen between hydrogen peroxide andwater has been observed during the interaction of hydrogen peroxide andOC1-, 104-, Mn04-, Fez+, Fe3+, and Ce4+ ions, and is attributed to theformation of peroxy-complexes. The exchange is much faster in nitric acidsolution than in solutions of sulphuric or perchloric acid, and it is suggestedthat it proceeds by the formation of N,05 and pernitric acid.The HO,radical is certainly formed during the peroxide-ceric ion reaction, butwhether this is compleved is ~nkn0~11.198Reviews of six- and eight-membered ring systems in sulphur chemistry lg9and of compounds containing sulphur-fluorine bonds 200 have been published.Sulphur reacts with lithium borohydride in ether, forming hydrogen,lithium sulphide, and a salt of formula LiB3S,H,; it is suggested that thiscompound contains an anion of structure ( 7 ) :Ig3L.Kolditz and D. Wass, 2. anurg. Chem., 1960, 307, 290, 304.lg4 G. S. Harris, Proc. Chem. Sue., 1961, 65.lS5 B. L. Chamberland and A. G. MacDiarmid, J., 1961, 445; J. Airier. Cfzein. SOC.,1961, 83, 549.lg6 E. Amberger, Ber., 1961, 94, 1447.lg7A. V. Grosse, A. G. Streng, and -4. D. Kirshenbaum, J . Amer. Chem. Suc., 1961,83, 1004.lgaM. Anbar, J . Anzer. Clzeni. SOC., 1961, 83, 2031; N. Anbar and S. Guttmann,ibid., p. 2035; E. Saito and B. H. J. Bielski, ibid., p. 4467.ls9 M. Becke-Goehring, Angew. Chem., 1961, 73, 589.200H. L. Roberts, Quart. Rev., 1961, 15, 30100 INORGANIC CHEMISTRYIn the absence of solvent, reaction takes place above 200°, and hydrogen andlithium dithioborate, LiBS,, are formed.201Sulphur tetrafluoride has been shown to be a very useful fluorinatingagent, converting mixtures of alkali metal or silver or thallous fluorides andmetal oxides, sulphides, or carbonyls into complex fluorides.202 It is alsouseful for the fluorination of uranium and plutonium oxides.,03 Adductsformed by sulphur tetrafluoride and boron trifluoride, arsenic pentafluoride,or antimony pentafluoride have been further described ; selenium tetra-fluoride displaces the sulphur compound from such adducts, and alsodisplaces bromine trifluoride from the adducts which the last compoundforms with auric fluoride and platinum tetrafl~oride.~~~ Man additionreactions of sulphur chloride pentafluoride to olefins and fluoro-olefinshave been described ; 205 reactions of fluoro-olefins with sulphur trioxidehave also been studied.206 Trifluoromethyl hypofluorite, CF,OF, reactswith sulphur trioxide at 250 O, forming trifluoromethyl peroxyfluorosulphon-ate, CF,-O*O-SO,F ; with sulphur dioxide, several products are formed,amongst them CP,*O*SO,F, CF,*O*SO,*O*CF,, CF,*O*SO,~O*SO,F, andCF3*O*S0,*O*S02*O*CF,, all of which are decomposed by aqueous allCali,though at markedly different rates.207 The peroxy-compound SFF*O*O+3F5is made by the interaction of SF,*OF and SOP, or SOP,, or by ultravioletirradiation of the first compound; it reacts only slowly with bases or withpotassium iodide (from which it liberates iodine). A wide range of physicalevidence supports the peroxy-formulation. 208 Disulphur dichloride ionisesvery slightly into S2C1+ and C1- ions and has been studied as a solventsystem. 209Disulphuryl fluoride reacts with ammonia at low temperatures accordingto the equationS,O,F, + 2NH, + F.SO,*NH, + NH,*SO,F.Analogous reactions take place with amines.210 Tetrasulphuryl fluoride,S4011F2, has been isolated from the products of the interaction of boron tri-fluoride and oleum, and polysulphuryl fluorides up to S,0,,F2, all havingacyclic structures, have been shown to be present.211 Boiling sulphur tri-oxide reacts with potassium cyanide to yield, in addition to a potassiumpolysulphate, sulphur dioxide, and paracyanogen, disulphuryl isocyanate,and a new compound (CN),,2S03; for the last, which can be made also bydirect combination of cyanogen and sulphur trioxide, the structure-O,S*N+iC*CiN +*SO,- is postulated.212 A large number of adducts of201H.Noth and G. Mikulaschek, 2. unorg. Chew., 1961, 311, 241.2oaR. D. W. Kemmitt and D. W. A. Sharp, J., 1961, 2496.203 C. E. Johnson, J. Fischer, and M. J. Steindler, J. Amer. Chem. SOC., 1961,83, 1620.204N. Bartlett and P. L. Robinson, J., 1961, 3417, 3549.205 J. R. Case, N. H. Ray, and H. L. Roberts, J., 1961, 2066, 2070.206D. C. England, M. A. Dietrich, and R. V. Lindsey, J. Amer. Chem. SOC., 1960,207 W. P. van Meter and G. H. Cady, J . Amer. Chem. SOC., 1960, 82, 6005.208C. I. Merrill and G. H. Cady, J. Amer. Chem. SOC., 1961, 83, 298.zoaH. Spandau and H. Hattwig, 2. unorg. Chem., 1961, 311, 32.210R. Appel and G. Eisenhauer, 2. unorg. Chem., 1961, 310, 90.211A. Simon and R.Lehmann, 2. anorg. Chem., 1961, 311, 224; R. J. Gillespie,212 H.-A. Lehmann, L. Riesel, K. Hohne, and E. Maier, 2. aizorg. Chem., 1961,310,298.82, 6181.J. T’. Oubridge, and E. A. Robinson, Proc. Chem. SOC., 1961, 428SHARPE: TYPICAL ELEMENTS 101sulphur trioxide and tertiary phenyl and cyclohexyl derivatives of Group Velements have also been reported.213 X-Irradiation of dithionites resultsin the formation of SO2- radical-ions which remain trapped in the lattice.ls8Tertiary phosphines react with tetrasulphur tetranitride according to theequationDiselenium dichloride reacts forming ( SeS2N2)C1,, 215 and potassium indimethoxyethane gives successively the S4N4-, S4N42-, S4NP3-, and S4N44-ions.216 The imide S7NH gives a substitution product S7N*BC12 on treat-ment with boron trichloride in carbon disulphide at -40°.217The decomposition of the oxyfluoride Se02P2 by ammonia yields a mix-ture of ammonium salts of cyclic triselenimide and of a series of poly(imid0-selenic acids) (e.g.the acid HO*Se02*NH*Se02*NH*Se02*OH) ; several othersalts have also been prepared.218Group VII.-Recent reviews have dealt with molecular complexes ofthe halogens, 219 the structures of interhalogen compounds and polyhalides,220halogen nitrates,221 polyfluoroalkyl compounds of metalloids and non-metals,222 and the physical and chemical properties of chlorine t r i f l ~ o r i d e . ~ ~ ~Work on liquid hydrogen halides as solvents has been continued,62* 224and it has been shown that Ph,N, Ph,As, Me20, Me2S, Ph,CCl, Ph,P, andPh,As can function as bases towards boron trichloride or methanesulphonicacid in liquid hydrogen chloride.By the action of bromine trifluoride on dinitrogen pentoxide in a Freonsolvent at low temperatures, bromine trinitrate, &(NO,),, is obtained;iodine reduces it to the mononitrate, which can also be obtained by the inter-action of bromine chloride and chlorine nitrate.Ozone converts it into thecompound BrO,*NO,, which is in turn converted by nitryl fluoride into theoxy!luoride Br0,F and dinitrogen ~ e n t o x i d e . ~ ~ ~ Some new compounds ofbromine, iodine, binary interhalogens, or positive halogen compounds witharomatic and heterocyclic bases have been prepared, and their infraredspectra have been studied.226 New polybromides of cobaltammines havealso been reported.227 Mixtures of stoicheiometric proportions of iodineRJ? + S,N, + R$'NIS, + S.213M.Becke-Goehring and H. Thielemann, 2. anorg. Chem., 1961, 308, 33,214H.-L. Krauss and H. Jung, 2. Naturforsch., 1961, 16b, 624.H. Garcia-Fernandez, Bull. Soc. chim. France, 1961, 1021.%lsD. Chapman, R. 31. Golding, A. G. Massey, and J. T. Moelwyn-Hughes, Proc.217H. G. Heal, J. Inorg. Nuclear Chem., 1961, 20, 165.218A. Engelbrecht and F. Clementi, Monatsh., 1961, 92, 555, 570.219 L. J. Andrews and R. M. Keefer, Adv. Inorg. Chem. Radiochem., 1961, 3, 91.220 E. H. Wiebenga, E. E. Havinga, and K. H. Boswijk, Adv. Inorg. Chem. Radio-221 M. Schmeisser and K. Brandle, Angew. Chena., 1961, 73, 388.222 R.E. Banks and R. N. Haszeldine, Adv. Inorg. Chem. Radiochem., 1961, 3, 338.223Y. D. Shishkov and A. A. Opalovskii, Uspekhi Khim., 1960, 29, 760 [357].224M. E. Peach and T. C. Waddington, J., 1961, 1238; F. Klanberg and H. W.Kohlschiitter, 2. Naturforsch., 1961, 16b, 69.225 hl. Schmeisser and L. Taglinger, Ber., 1961, 94, 1533.226 R. A. Zingaro and W. B. Witmer, J. Phys. Chem., 1960, 64, 1705; R. D. Whit-aker, J. R. Ambrose, and C. W. Hickman, J. Inorg. Nuclear Chem., 1961, 17, 254;A. I. Popov, J. C. Marshall, F. B. Stute, and W. B. Person, J. Amer. Chem. SOC., 1961,83, 3586.227 N. I. Lobanov and 0. S. Konovalenko, Zhur. neorg. h-hini., 1960, 5, 847 [407].Chem. Soc., 1961, 377.chem., 1961, 3, 133; R. E. Rundle, Acta Cryst., 1961, 14, 685102 INORGANIC CHEMISTRYpentafluoride and iodine, or bromine trifluoride and bromine, act as sources ofthe monofluorides for addition to fluoro-olefhs.228New molecular complexes of iodine which have been reported includethose with hydrogen ~ u l p h i d e , ~ ~ ~ amides, diethyl sulphide, and diethyl di- 'sulphide.230 The monosulphide is a much better donor than the disulphide,an order analogous to that obtained for diethyl ether and di-t-butyl per-oxide.The infrared and Raman spectra for some of the simpler polyhalideions have been presented and force constants have been calculated. Fortrihalide ions the stretching force constants are only about one half of thosein the free halogens, and it is concluded that the rather weak bonds in theseions are best considered as involving only p orbitals.231 The complex py,212has been shown to contain centrosymmetric, almost planar py21+ ions; theanion I,- is a loose complex of I,- and Z12.232 A wide range of evidenceleads to the conclusion that the blue solutions obtained when iodine or iodinemonochloride is dissolved in 65% oleum, lOOyo sulphuric acid, or fluoro-sulphonic acid contain I+ ions.The effective magnetic moment of 1-5 B.M.per gram-atom of iodine is attributed to the possession of the electronicstructure 5s25p4 by the cation, with a large crystal field stabilisation andsplitting of the electronic levels by the surrounding solvent.233The stabilities of the 1,Cl- and E l 2 - ions in aqueous media have beeninvestigated, and the latter has been shown to be much the more stable.When iodine trichloride is dissolved in aqueous hydrochloric acid, the ICI, -ion is not formed, and the reaction2IC1, + 3H,O --+ 10,- + IC1,- + 4C1- + 6H+takes pla~e.23~ Alkaline solutions of iodine have been shown to containthe &OH- i0n:235 k for the reactionI, + H20 -+ 1,OH- + H+is estimated as one hundred times greater than that forI, + H,O--+HOI + I- + H+.The salt NHiCrIO,, obtained from iodic acid and ammonium dichromate,contains a CrI0,- ion consisting of a CrO, tetrahedron sharing one oxygenatom with a IO, pyramid.236The preparation of astatine from the products of the action of high-energy protons on thorium has been described; it is said that, contrary toearlier statements, sulphur dioxide reduces oxidised forms of astatine onlyto the element.237 The existence of polyhalide ions containing astatine228R. D.Chambers, W. K. R. Musgrave, and J. Savory, Proc. Chem. SOC., 1961,229 J. Jander and G. Turk, Angew. Chem., 1961, 73, 63.2 3 0 H . Tsubomura and R. P. Lang, J. Amer. Chem. SOC., 1961, 83, 2085.231W. B. Person, G. R. Anderson, J. N. Fordemwalt, H. Stammreich, and R.2 3 2 0 . Hassel and H. Hope, Acta Chem. Scand., 1961, 15, 407.233 J. Arotsky, H. C. Mishra, and M. C . R. Symons, J., 1961, 12.234D. L. Cason and H. M. Neumann, J . Amer. Chem. SOC., 1961, 83, 1823.235 J. Sigilla, J . Chim. phys., 1961, 58, 002.236K. Wilhelmi and P. Lofgren, Acta Chem. Scand., 1961, 15, 1413.237 M. Lefort, G. Simonoff, and X. Tarrago, Bull.SOC. chim. France, 1960, 1726.113; J., 1961, 3779.Forneris, J . Chem. Phys., 1961, 35, 908SHARP: THE TRANSITION ELEMENTS 103(e.9. At1,-, AtIBr-, AtC1, --) has been dem~nstrated,~~s and the solutionchemistry of astatine has been expressed in a new potential diagram 239At--At- HOAt(?)- AtO,- H,AtO,( ?)-0-3 -1.0 - 1.5 < -1.6 VA. G. S.3. THE TRANSITION ELEMENTSTHE transition elements will be considered in an order similar to that adoptedlast year. General reviews published during the year include articles onthe borides and silicides of the transition elements,l on the dissociationenergies of gaseous metal dioxides,2 and on the uses of electron-spinresonance as applied to crystalline transition-metal compounds. In ageneral paper, the Kapustinskii formula has been used to calculate thelattice energies and enthalpies of formation of the transition-metal halidesMX, MX,, and MX, from scandium to zinc.It is shown that, from thethermodynamic viewpoint, several hitherto unknown halides should becapable of existence.An extremely important new book gives themathematical approach to the theory of transition-metal ions, and thequalitative applications are dealt with in two other books,6 one of whichis designed as an introductory text for students.‘ The Tilden lecture ofthe Chemical Society has dealt with the electronic configurations and struc-tures of transition-metal complexes * and there has been a general review onthe complexing of metallic cation^.^ More specialised reviews have dealtwith the chemistry of inner complexes,10 oxalato-complexes,ll complexesof biguanides and guanylureas,12 and with polymeric chelate compounds.l3Current experimental work suggests that greater emphasis must be givento n bonding when all types of complex are being considered. A study ofthe stability constants of some chromium(n) and vanadium(=) complexeshas been interpreted as showing that n bonding has a greater influence onthe stabiLity of complexes derived from cations in the first half of the firstComplexes.-( a) General.23*E. H. Appelman, J. Phys. Chem. 1961, 05, 325.239 E. H. Appelman, J . Amer. Chem. SOC., 1961, 83, 805.IB. Aronsson, ArEiv Kemi, 1961, 16, 379.eL. Brewer and G. M. Rosenblatt, Chem. Rev., 1961, 61, 257.3A. Carrington and H.C. Longuet-Higgins, Quart. Rev., 1960, 14, 427.*M. Barber, J. W. Linnett, and N. H. Taylor, J., 1961, 3323.ti J. S. GrifEth, “ The Theory of Transition Metal Ions,” Cambridge Univ. Press,L. E. Orgel, “ An Introduction t o Transition Metal Chemistry,” Rlethuen,7 D. P. Graddon, “ An Introduction to Co-ordination Chemistry,” Pergamon,sR. S. Nyholm, Proc. Chem. SOC., 1961, 273.London, 1961.London, 1960.London, 19G1.G. Schwarzenbach, Adv. Inorg. Chem. Radicchem., 1961, 3, 257.lo B. 0. West, Rev. Pure Appl. Chem. (Australia), 1960, 10, 207.l1 R. V. Krishnamurty and G. M. Harris, Chem. Rev., 1961, 61, 213.l2P. Rgy, Chem. Rev., 1961, 61, 313.laA. A. Berlin and N. G. Matveeva, Uspekhi Khim., 1960, 29, 277 [119].** The page number of the English translation of Russian chemical journals is givenin brackets104 INORUANIC CHEMISTRYrow of the transition series than from those in the second half (manganese tozinc).An immediate consequence of this is that the stability sequence forhigh-spin dipositive complexes of the first part of the transition series isligand-dependent . l4 The interpretation of absorption spectra of copper( II),copper(r), and iron(=) complexes requires a relative emphasis of the effectsof n and cr bonding Merent from that for the interpretation of stabilitydata.l5 The influence of crystal-field stabilisation is considered to have aneffect on adsorption a t a surface. The adsorption of oxygen on nickel oxidecompletes the octahedral field for the surface nickel atoms, and the oxygen isphotodesorbed on irradiation with light of a wavelength corresponding tothe chi! transitions in nickel oxide.The photodesorption is believed to pro-ceed by excitation of the nickel atom, desorption, and assumption of a tetra-hedral configuration with greater crystal field stabilisation.16 Further physi-cal studies have been made on the trans-effect in planar complexes. Nuclearmagnetic resonance shifts for the 18 protons in pyridine-platinum complexescan be interpreted in terms of n bonding between the metal and the halogenin the transposition relative to the pyridine, but kinetic studies of thedisplacement of halogen in complexes [MClR(PR’,),] (M = Ni, Pd, Pt;R = R’ = alkyl, aryl; R = hydrogen) can only be interpreted in terms ofboth polarisation and n b0nding.l‘ A study has been made of the thermo-dynamics of co-ordination at the sixth position in di(pentane-2,4-diono)oxo-vanadium(rv). The entropy change is greater than that measured for com-parable processes in solution but is considered to be a true entropy of co-ordination; it bears little relation to the chemical properties of the ligand.18Previous studies on the exchange of [ 15N]ammonia between aqueous ammo-nia and the ligands in metal ammines have indicated slow exchange, butrecent work on copper, silver, nickel, and aluminium ammines has indicatedrapid exchange with half-lives for the exchanges varying between 0.3 and3 sec.19 An extensive survey of the compounds MX,py, (X = halogen,py = pyridine) by various physical methods has shown that the co-ordina-tion about the metal may be tetrahedral, octahedral, or square planar; theinfrared spectra of these and other pyridine complexes are considered toindicate considerable back bonding from the metal to the pyridine.20 Theoxidation-reduction potentials of Cu(~)-Cu(n) complexes of substitutedderivatives of 2,2’-bipyridyl and o-phenanthroline are not related to theacid dissociation constants of the protonated ligands but to the co-ordinationnumber of the metal which is, in turn, related t o the bulk of the ligand.21The reduction of aryl nitro-derivatives by sodium borohydride is strongly14 J.M. Crabtree, D. W. Marsh, J. C. Tomkinson, R. J. P. Williams, and W. C.Fernelius, Proc. Chem.SOC., 1961, 336.15B. R. James, M, Parris, and R. J. P. Williams, J., 1960, 4630.l6 J. Haber and F. S. Stone, Proc. Chem. SOC., 1961, 424.1’A. D. Westland and L. Westland, Canad. J . Chem., 1961, 39, 324; F. Basolo,18R. T. Claunch, T. W. Martin, and M. 31. Jones, J . Amer. Chenz. Soc., 1961, 83,10 J. R. Sutter and J. P. Hunt, J . Amer. Chem. SOC., 1060, 82, 6420.20N. S. Gill, R. S. Nyholm, G. A. Barclay, T. I. Christie, and P. J. Pauling, J.Inorg. Nuclear Chem., 1961,18, 88; N . S. Gill, R. H. Nuttall, D. E. Scaife, and D. W. A.Sharp, ibid., p. 79.J. Chatt, H. B. Gray, R. G. Pearson, and B. L. Shaw, J., 1961, 2207.1073.21B. R. James and R. J. P. Williams, J . , 1961, 2007SHARP: THE TRANSITION ELEMENTS 105catalysed by transition-metal derivatives.When [Cobipy,13 + (bipy = 2,2'-bipyridyl) is acting as catalyst it is considered that [Cobipy,] + is the effectivereducing agent.22 In a series of octahedral complexes the degeneracy ofthe tzg orbitals can be removed in certain circumstances by the effect ofstrong n bonding and the diamagnetism of [Tiphen,1° (phen = o-phen-anthroline) is due to this orbital ~plitting.,~ Malonaldehyde (1) and formyl-R,acetone (2) complexes of chromium(rn) have been prepared by what ap-pears to be the general method of adding a mixture of chromium(=) andchromium(m) salts to a donor solvent containing an ionic salt of the ligand.Malonaldehydato-complexes are the simplest members of the series of,!Miketone complexes.24 The magnetic properties of many series of saltshave been systematically studied and of particular importance is the workon d3, d4, and tgg c0mplexes.2~ The magnetic susceptibilities of bi-nuclear complexes of iron and chromium with one, two, or three bridginggroups have been interpreted in terms of magnetic exchange between thepairs of metal atoms.26 From a study of infrared spectra it is concludedthat there is as much back bonding in isocyanide complexes as in carbonyls;for complexes of zero-positive metals this effect is so great that the isocyanidegroup becomes bent.27 Complexes have now been prepared for which infra-red spectra indicate bidentate sulphito- and sulphato-groups. The com-plexes [Co en,SO,]X (en = ethylenediamine; X = ClO,, NO,, I, SCN) and[ Co en2S04]X (X = Br, C10,) contain the bidentate ligands but in complexesof the types [Co en,(SO,)(H,O)]+ and [Co en,(SO,)X]+ the sulphato- andsulphito groups are unidentate (for a further example of a bidentate sulphategroup see ref.27a).28 Infrared spectra can also be used to distinguishbetween the various types of bonding possible with a perchlorate group.Most perchlorato- complexes contain the unidentate ligand but anhydrouscupric and ferric perchlorates may contain bidentate perchlorate groupings.29The infrared spectra of a number of metal acetylacetonates have been studiedin detail but it has proved difficult to come to conclusions about the natureof the metal-oxygen bonds because of the coupling of the M-0 vibrationswith the other vibrations in the molecule.Crystal-structure studies of theisomorphous aluminium, chromium, and cobalt derivatives show that.22 A. A. VlEek and A. Rusina, Proc. Chem. Soc., 1961, 161.23 L. E. Orgel, J., 1961, 3683; R. Perthel, 2. phys. Chem. (Leipxig), 1959, 211, 74.24 J. P. Collman and E. T. Kittleman, J. Amer. Chern. SOC., 1961, 83, 3529.25 A. Earnshaw, B. N. Figgis, J. Lewis, and R. D. Peacock, J . , 1961, 3132; B. N.Figgis, J. Lewis, and F. E. Mabbs, J., 1961, 3138; B. N. Figgis, Trans. Paraday SOC.,1961, 5'7, 204.z s A . Earnshaw and J. Lewis, J., 1961, 396.27 F. A. Cot,ton and F. Zingales, J . Arner. Chem. SOC., 1961, 83, 351.zsaC. K. Prout and H. M. Powell, J., 1961, 4177.28 C. G. Barraclough and M. L. Tobe, J., 1961, 1993; M. E. Baldwin, J . , 1961, 3123.2s B.J. Hathaway and A. E. Underhill, J., 1961, 3091; cf. 33. M. Jones, E. 9.Jones, D. F. Harmon, and R. T. Semmes, J . Anzer. Chem. Soc., 1961, 83, 2038106 INORGANIC CHEMISTRYthere are very similar atomic separations in all of these complexes and arenot in favour of theories which would relate the electron density inthe chelate ring to the number of d-electrons present or the number ofd-orbitals available on the metal atoms.30 Trends in the infrared spectraof complex chlorides run parallel to those observed for other metal-ligandvibrations.31Substitution reactionshave been reviewed 32 and the full report has been published of a FaradaySociety Discussion on oxidation-reduction processes in ionising solvents. 33The reactions of the reducing agent V2faq.with oxidising agents RL(R = Co111(NH3),; L = OH,, NH,, C1) have been found to proceed throughan outer-sphere complex rather than a bridged complex as is found whenCr2+aq. is used as the reducing agent. This difference in mechanism isrelated to the fact that in the case of V2+ it is a t2, electron which is beingtransferred and that the orbital can overlap with an orbital of the oxidant;in the case of Cr2+ the electron to be transferred is in an eg orbital whichis poorly situated for overlap with a receiving orbital and the electron mustbe transferred by way of a bridge.34 When the reducing agent is Crz-taq.and L is a half-ester, the attack is on the adjacent carboxyl group in allcases except for the hydrogen fumarate and methyl fumarate (half ester) andthe terephthalate where the ligand contains a conjugated double bond.Inthese cases there is 'attack at the remote end and a simultaneous protonattack on the near carboxyl group which aids conjugation in the ligand;ester hydrolysis occurs at the same time as the oxidation-reduction process.When L is hydrogen or methyl maleate there is isomerisation t o fumaricacid ; the ester hydrolysis occurs through alkyl-oxygen fission rather thanby acyl-oxygen fission as is more normally observed in ester hydrolysis.Replacement of the methylene hydrogens by ethyl groups shows that forthe (hydrogen maleato) -complex the methylene hydrogens are dissociatedin the intermediate state; this dissociation gives rise to more ready charge-transfer through the ligand.35 The rate of hydrolysis of halogenopentam-minechromium(m) ions is increased by the presence of sodium salts of weakacids and it is suggested that ion-pair formation with partial charge-transferhelps to maintain an octahedral configuration in the transition state.36Direct oxygenation of Cr2+ in ammoniacal solution to give binuclear species[ (NH3),Cr*O*Cr(NH3),1* + occurs by way of the peroxy-bridged complex[ (NH3),Cr*02*Cr(NH3),]*+ and the chromium(Iv) ion [ (NH3),Cr1v(OH)]3 +.37Acid cleavage of tetra-t-butoxychromium(1v) is of the Cr-0 bond; this(b) Mechanisms of reactions of inorganic complexes.'3O J.P. Dismukes, L. H. Jones, and J. C. Bailar, jun., J. Phys. Chem., 1961, 65,792; K. Nakamoto, P. J. McCarthy, A.Ruby, and A. E. Martell, J . Amer. Chem. SOC.,1961, 83, 1066; E. A. Shugam and L. M. Shkol'nikova, Doklady Akad. Nauk S.S.S.R.,1960, 133, 386.31D. M. Adains, Proc. Chem. SOC., 1961, 335.32 F. Basolo and R. G. Pearson, Adv. Inorg. Chem Radiochem., 1961, 3, 1.33 Discuss. Paraday SOC., 1960, 29.34A. Zwickel and H. Taube, J. Amer. Chem. Soc., 1961, 83, 793.35 D. K. Sebera and H. Taube, J. Amer. Chern. SOC., 1961,83, 1785; R. T. M. Fraser36T. P. Jones, W. E. Harris, and W. J. Wallace, Canad. J. Chem., 1961, 39, 2371.37 T. B. Joyner and W. K. Wilmarth, J. Amer. Chein. SOC., 1961, 83, 516.and H. Taube, ibid., pp. 2239, 2242; G. Svatos and H. Taube, ibid., p. 4172SHARP: THE TRANSITION ELEMENTS 107agrees with the postulated mechanism for the oxidation by chromium(v1)of organic derivatives as proceeding through a chromium(1v) alkoxide withretention of configuration.38 The initial step in the oxidation of manga-nate( VI) to permanganate(m) by hypochlorite is disproportionation tomanganate(v) and permanganate( VII) ; the subsequent oxidation of manga-nate(v) to permanganate(vr1) is slow.39 Ligands in which oxygen is bondedto the metal increase the rate of uptake of molecular oxygen by iron(n)solutions whilst nitrogen-containing ligands have no such effect.It ispostulated that n bonding in the former complexes increases the electrondensity in the iron(n) tzs orbitals and favours electron transfer to a co-ordinated dioxygen molecule but that such n bonding does not occur inthe nitrogen c~mplexes.~O Since the rate of oxidation of iron(@ ions byiron(m) complexes of substituted o-phenanthroline, 2,2'-bipyridyl, and2,2,2"-terpyridine derivatives is related only to the basicity of the ligandsand is not influenced by steric effects it is suggested that electron transferdoes not take place with the reducing agent at the periphery of the iron(nr)complex but that the iron@) must penetrate between the ligands and makealmost direct contact with the iron(m), a mechanism similar to that envisagedfor the reductions by V2 +aq.mentioned above. 41 The propylenediamine-tetra-acetatocobaltates(n and 111) both exist almost exchsively in the formof one enantiomer and electron transfer between the two species takes placewith complete retention of configuration for both species.Substitution ofother chelating agents into et hy lenediamine - and prop y lenediamine - t etr a -acetato-complexes also occurs with retention of c0nfiguration.4~ Thephotochemically initiated redox and substitution reactions of some cobalt(II1)and chromium(m) complexes have been discussed in terms of two mechan-isms. The first is activation by electronic excitation and the second involvescharge transfer in and subsequent fission of a metal-ligand bond. Thelatter theory is favoured by experiments with light of different energies;for light of short wavelengths both aquation and reduction should takeplace with high quantum yield but long-wavelength radiation should giveonly ionic dissociation ; both predications are in accord with ob~ervation.~~Substitution of nitrite into chloroplatinum(1v) ammines occurs by way ofa slow reduction of platinum(1v) to platinum(I1) followed by a two-electronoxidation involving a bridged intermediate.The necessity for the bridgedintermediate can be used to explain the impossibility of substituting morethan five nitro-groups into the PtClG2- The exchange reaction be-tween mercury aryls and alkyls, HgRR', and mercuric halides, HgX,, is38K. B. Wiberg and G. Foster, Chem. and Ind., 1961, 108.39 M. W. Lister and Y. Yoshino, Canad. J. Chem., 1961, 39, 96.40T. Kaden and S. Fallat, Helv. Chim. A d a , 1961, 44, 714.41M. H. Ford-Smith and N. Sutin, J. Amer. Chem. Xoc., 1961, 83, 1830.42 F. P. Dwyer and F. L. Garvan, J.Amer. Chem. SOC., 1961, 83, 2610; Y. A. Imand D. H. Busch, ibid., p. 3362; H. Irving and R. D. Gillard, J., 1960, 5266; 1961,2249; cf. S. Kirschner, Y.-K. Wei, and J. C. Bailar, jun., J. Smer. Chem. Xoc., 1957, '79,5877.43 H. L. Schlafer, 2. Elektrochem., 1960, 64, 887; A. W. Adamson, Discuss. FaradaySOC., 1960, 29, 163; Z. Simon, Canad. J. Chem., 1960, 38, 2373.44H. R. Ellison, F. Basolo, and R. G. Pearson, J. Amer. C'irem. SOC., 1961, 83,3943; I. I. Chernyaev, L. A. Nazarova, and A. S. Mironova, Zhur. neorg. Khim., 1959,4, 747 [340]108 INORGANIC CHEMISTRYbelieved to take place through an intermediate (e.g., 3) in which mercury istaking part in two three-centre bonds.45(c) Curbonyls. Technetium carbonyl, Tc,(CO),,, hasnow been prepared by the action of carbon monoxide on\ / Tc20,; it reacts with iodine to give [Tc(CO,)I], whichSomenew reducing agents have been described which are claimedto be effective in reductive carbonylation reactions ; sodium in diethyleneglycol dimethyl ether (diglyme) and zinc dust in ether or dichloroethane areeffective in producing Group VI ~arbonyls.~' The elusive Mn2(C0),, can beprepared in good yield by the action of carbon monoxide and sodium indiglyme on n-methylcyclopentadienylmanganese tricarbonyl.,* The ex-change reactions of metal carbonyl derivatives have been examined in somedetail.Group VI hexacarbonyls do not undergo exchange with labelled car-bon monoxide in the dark but there is rapid exchange under the influence ofultraviolet light.The exchange appears to occur by wa.y of dissociationto give M(CO), intermediates ; the interaction of these intermediates withother ligands is an ideal method for the preparation of substituted car-bonyls.,g Nickel and cobalt carbonyls also undergo exchange of carbonmonoxide by dissociative mechanisms : for dicobalt octacarbonyl all of thecarbonyl groups are equivalent with respect to exchange. Mn(CO),Xderivatives undergo exchange of both carbon monoxide and X by flxlmechanisms but Fe(CO),I, exchanges carbon monoxide by an XNl mechan-ism and iodine by an 8,2 mechanism. n-Cyclopentadienylmetal carbonylsgenerally undergo exchange of carbon monoxide by EX2 mechanisms. 5OSome reactions of vanadium hexacarbonyl have now been reported.With triphenyl-phospine , -arsine, and -stibine it gives substituted complexesL2V( CO), ; the phosphine complex is reduced to the [V-l(CO),(Ph,P>] -anion by sodium amalgam.Nitrogen and oxygen bases cause dispropor-tionation to give salts [V11L,][V-1(CO)6], (n = 4 or 6); on acidification theanions give the hydrides V(CO),H and V(CO),(Ph,P)H.51 The salts[Nadiglyme,][M(CO),] (M = V, Nb, Ta) are prepared in good yield by theaction of carbon monoxide and excess of sodium in diethylene glycoldimethylether on the metal pentahalides. Phosphoric acid converts the hexacar-bonylvanadate( -I) t,o vanadium hexacarbonyl in good yield but niobiumand tantalum carbonyls have yet to be isolated. 52 Iodopentacarbonyl-CIEt / Hg\phc , Hg (3) gives Tc(CO),I with excess of carbon rn~noxide.~,45 R.E. Dessy, Y. K. Lee, and J.-Y. Kim, J . Amer. Chem. SOC., 1961, 83, 1163;0. A. Reutov and G. M. Ostapchuk, Zhur. obshchei Khim., 1959, 29, 1614 [1588].46 J. C. Hileman, D. K. Huggins, and H. D. Kaesz, J . Amer. Chem. Soc., 1961, 83,2953; cf. W. Hieber and C. Herget, Angew. Chem., 1961, 73, 579.47 H. E. Podall, H. B. Prestridge, and H. Shapiro, J . Amer. Chem. SOC., 1961, 83,2057; V. L. Volkov, E. P. Mikheev, K. N. Anisimov, L. E. Eliseeva, and Z. P. Valueva,Zhw. neorg. Khim., 1958, 3, 2433.4aH. E. Podall and A. P. Giraitis, J . Org. Chem., 1961, 26, 2587.4eTV. Strohmeier and R. Muller, Z . phys. Chem. (Frankfurt), 1961, 28, 112.50F. Basolo and A. Wojcicki, J . Amer. Chem. SOC., 1961, 83, 520; A. Wojcickiand F. Basolo, J .Irwrg. Nuclear Chem., 1961, 17, 77; W. Hieber and K. Wollman,Chem. Ber., 1961, 94, 305.s1 W. Hieber, J. Peterhans, and E. Winter, Chent. Ber., 1961, 94, 2572; R. P. M.Werner, 2. Naturforsch., 1961, 16b, 477.52 R. P. M. Werner and H. E. Podall, Chem. and I?id., 1961, 144SHARP: THE TRANSITION ELEMEXTS 109chromates(0) react with iodine to give Cr(CO),I. This blue compoundinsoluble in water is the first carbonyl halide of a Group VI element.53Chromium and molybdenum carbonyls react with sodium borohydride inammonia and &ethylene glycol dimethyl ether to give Na,M,(CO),, andNa,M,(CO),, in the two solvents, respectively; the pentacarbonylchromate-(-11) anion can be oxidised by water to the [Cr,(CO),,H]- ion.5* Thereaction between metal carbonyls an'd sulphur trioxide yields what arebelieved to be pyrosulphato-complexes, (OC),MoO( SO,),, (OC),MnO(SO,),,and ( OC),FeO(S0,),.55 Metal carbonyl cations have been described for thefirst time; they are generally prepared by the action of excess of carbonmonoxide on a metal carbonyl halide in the presence of a strong Lewis acidsuch as aluminium chloride.Co-ordination of olefins or phosphines canalso stabilise the cation and examples of such substituted cations will befound elsewhere in this Report. The carbonyl cations described in the litera-ture during 1961 are [Mn(CO),]+, [Re(CO),]+, [Fe(Co),12+, and [os(Co)6]2+,all isoelectronic with the Group VI hexacarbonyls. 56 Dimanganese decacar-bony1 is reduced by sodium borohydride when in tetrahydrofuran solutionto give H,Mn,(CO),; this is the first binuclear carbonyl hydride of a metalof odd atomic number.,' The first example of a new class of compound isproduced when manganese carbonyl reacts with dinitrogen tetroxide to give&h(N03)(C0)5.5s Triphenylarsine was previously considered to react withmanganese carbonyl to give an adduct but this has now been identified as'an arsenide [Ph,AsMn(CO),],; the arsenic atoms act as bridges between thetwo manganese atoms, and there is no longer any necessity to postulatea inetal-metal bond.59 X-Ray studies show that the compounds describedin the older literature as enneacarbonyls, M,(CO), (M = Ru, 0s) are in facttrimetal dodecacarbonyls, M,(CO),,.Go Phosphinetricarbonylcobaltates( -I)are prepared by the action of sodium in tetrahydrofuran on the appropriatephosphinecobalt carbonyl.They give hydrides, HCo( CO),PR,, on acidifica-tion, and the sodium salt reacts with methyl iodide to give the methylderivatives Me*Co(CO),*PR,. 61 Cobalt carbonyls react with organic deriva-tives CX,Y [X = halogen; Y = Me, C1, F, Ph, CO,Et, CO,H, CH(OAc),,and CF,] to give complexes [Co,(CY)(CO),] of exactly the same type as resultfrom the treatment of acetylenehexacarbonyldicobalt complexes with acid. 62The cobalt carbonyl sulphide, Co,S(CO),, which is prepared by the actionof carbon monoxide on Co,S(CO),, has a similar stoicheiometry and mayhave a similar structure.63 Rhodium carbonyl chloride has a most unusualstructure (4) in which two planar Rh(CO),Cl units intersect a t an angle and63H.Behrens and H. Zizlsperger, 2. Nuturforsch., 1961, 16b, 349.s4H. Rehrens and W. Haage, Chem. Ber., 1961, 94, 312, 320.s5 R. P. M. Werner, Chem. Ber., 1961, 94, 1207.66 E. 0. Fischer and K. Ofele, Angew. Chem., 1961, 73, 551; W. Hieber and T.s7 W. Hieber, W. Beck, and G. Zeitler, Angeu-. Chem., 1961, 73, 364.58C. C. Addison, &.I. Kilner, and A. Wojcicki, J., 1961, 4839.59R. F. Lambert, Chem. and Ind., 1961, 830.soE. R. Corey and L. F. Dahl, J . Amer. Chem. Soc., 1961, 83, 2203.61 W. Hieber and E. Lindner, 2. Nuturforsch., 1961, 16b, 137.62W. T. Dent, L. A. Duncanson, R. G. Guy, H. W. B. Reed, and B. L. Sliaw,63L. Mark6, G. Bor, and E. Klumpp, Chem. and Id., 1961, 1491.Kruck, ibid., p, 580.Proc.Chem. Xoc., 1961, 169; cf. Ann. Zeports, 1960, 57, 148110 IN 0 RG AN I C CHEMISTRYBond lengths and angles in Rh(CO),Cl.(Reproduced with permission from J. Amer. Chem. SOC., 1961, 83, 1762.)are joined by two chlorine bridges, both on the same side of the line joiningthe two metal atoms. These dimers are linked by Rh-Rh bonds to forminfinite chains and a second, but this time bent, metal-metal bond is sug-gested in the dimers. This is formed by overlap of a-type orbitals a t anangle of 56" and such bent metal-metal bonds are suggested as a generalphenomenon in metal carbonyl c~mplexes.~~ Carbon monoxide at highpressures reacts with' K,IrBr, and K,IrCl, to produce a wide variety ofcarbonyl complexes which can be converted into one another by variouschemical processes. Anions of the types [Ir(CO),X,]2 -, [Ir,(C0)4X,] -, and[Ir2(C0),X2] are reported.65 The [Ni4(CO) J2- anion has previously beenshown to result from the reduction of nickel carbonyl with solutions of alkalimetals in liquid ammonia but ammonolysis can lead to a binuclear hydride,H2Ni2(C0),.66 Silver and mercuric salts are good catalysts for the oxidationof carbon monoxide.Carbon monoxide enters into reaction by insertionbetween the metal and the oxygen in an Ag-OH or Hg-OH, grouping (thelatter complex then loses a proton). Both of these processes are favouredby high pH and reaction occurs very readily in the case of the silver am-mines. Mercuric acetate reacts with carbon monoxide in methanol to give aseries of products, XHg*CO*OMe, which appear to be derived from the reac-tion of a mercury methoxide with carbon monoxide.67Nitric oxide reacts with V(CO), and V(CO),(Ph,P), togive V(CO),(NO) and V(CO),(Ph,P)(NO), respectively.Pentacarbonyl-nitrosylvanadium( -I) is isoelectronic with chromium he~acarbonyl.~~, 68 A64 L. F. Dahl, C. Martell, and D. S. Wampler, J. Amer. Chem. SOC., 1961, 83, 1761.G5L. Malatesta and F. Canziani, J. Inorg. Nuclear Chern., 1961, 19, 81.66H. Behrens and F. Lohofer, Chem. Ber., 1961, 94, 1391.67 J. Halpern and S. F. A. Kettle, Chem. and Ind., 1961, 668; A. C. Harkness andJ. Halpern, J. Amer. Chem. SOC., 1961, 83, 1258; S. Nakamura and J. Halpern, ibid.,p. 4102.6aR. P. M. Werner, 2. Naturforsch.. 1961, 16b, 478.(d) NitrosylsSHARP: THE TRANSITION ELEMENTS 111new nitrosylcarbonyl of manganese, Mn(CO),(NO), isoelectronic with ironpentacarbonyl, is prepared by the action of N-methyl-N-nitrosoto1uene-p-sulphonamide on manganese carbonyl hydride in ether.It is very sensitiveto oxidation and on irradiation with ultraviolet light gives Mn,(CO)7(N0),.69Iodotetracarbonyltriphenylphosphitomanganese reacts with nitric oxide togive two nitrosyls, [ (PhO),P]Mn(NO),, analogous to the nitrosyl preparedby the action of nitric oxide on the corresponding triphenylphosphine com-plex, and a new type of complex, [(Ph0)3P],Mn(NO)21.70 Many othersubstituted metal nitrosyls have been prepared by reaction of metal nitrosylhalides with ligands L such as triphenyl-phosphine, -arsine, and -stibine.They are of the types Fe(NO),LX, Fe(NO),L,, Co(NO),LX, Rh(NO)(R,P),,Rh(NO)(R,P),Cl,, [Ni(NO)LX],, and Ni(NO)L,X. The compound[Co(NO),Cl], reacts with tertiary phosphines in the presence of sodiumama,lgam to give Co(NO)L, derivatives ; the parent compoundJ Ni(NO),( Ph,P),,of the series of halogenonitrosylphosphinenickel complexes is prepared bythe action of nitric oxide on Ni(C0)2(Ph3P),.71 The range of iron(1r) andcobalt(=) salts that give nitrosyls by direct addition of nitric oxide hasbeen extended by the preparation of adducts with di( salicyla1dehydato)-dipyridineiron(n) ; diacido-di- (8-aminoquinoline)cobalt( 11) (chloride andnitrate) ; and di(histidino)cobalt(11).7~ K,Ru(NO)Cl, has a defarmed(NH3),FeF6 structure ; the Ru-N-0 grouping is linear.', Many nitrosyl-ruthenium species have been postulated to exist in solutions of nitrosyl-ruthenium in water and tributyl phosphate but only Ru(NO)(NO,),(H,O)~ haspreviously been isolated. However, new compounds, KRu(NO)(NO,),,H,Oand Ru(NO)(NO,),[ (BuO),PO],, have now been obtained from these solu-tions.74 [Co(NH,),(NO)]Cl reacts with potassium cyanide and water to giveK2[ HCo( CN)5(N0)],2H,0 which yields K3[ Co( CN),( N0)],2H20 with aqueouspotassium hydroxide.Water reconverts the [CO(CN),(NO)]~- anion intothe [HCo(CN),(N0)l2- ion. There is no information as to how the hydrogenis bonded in these species.75 The nitric oxide complexes of nickel, palla-dium, and platinum have been re-investigated and six- and four- co-ordinatedderivatives have been found.Nickel carbonyl reacts with nitric oxide andammonia in the presence of water to give [Ni(NO)(NH,),(OH)](OH),; inmethanol the same reaction gives [Ni(NO)(NH,)( OMe)( OH)]OH which isconverted into a hydroxy-complex with nitro-bridges when refluxed.Treatment of dipotassium tetranitropalladate(11) with nitric acid yieldsK2[Pd(NO)(N02),(N0,)]J and the platinum salt can be prepared similarly.Nitric oxide gives a green solution with aqueous dipotassium tetrachloro-platinate(rr), and a pyridine adduct [Ptpy2(N02)C1] can be isolated.69 P. M. Treichel, E. Pitcher, R. B. King, and F. G. A. Stone, J . Amer. Chem. SOC.,1961, 83, 2593.7 0 W. Hieber, W. Beck, and H. Tengler, 2. NatuTforsch., 1961, 16b, 68.i1 W.Hieber and K. Heinecke, 2. Naturforsch., 1961, 16b, 553, 554; W. Hieberand R. Kramolowsky, ibid., p. 555; W. Hieber and I. Bauer, ibid., p. 556; W. P.G r a t h , J. Lewis, and G. Wilhson, J., 1961, 2259.72 R. Nast and H. Riickemann, 2. anorg. Chem., 1961, 307, 309; R. Nast, H. Bier,and J. Gremm, Chem. Ber., 1961, 94, 1185; P. Silvestroni and L. Ceciarelli, J . Amer.Chem. SOC., 1961, 83, 3905.73T. S. Khodashova and G. B. Bokii, Zhur. strulct. Khim., 1960, 1, 161.54D. Scargill and J. M. Fletcher, Proc. Chem. SOC., 1961, 251.75R. Nast and R. Thome, 2. anorg. Chem., 1961, 309, 283112 INORGANIC CHEMISTRYNitrosyl chloride adds directly to four-co-ordinate platinum(n) complexesto give compounds of the type PtII(NO)L,, and nitric oxide reacts withtetrammineplatinum(x1) chloride in nitric or acetic acid to give complexesformulated as [ Pt(N0) (NH3)4( OAc)]Cl, or [ Pt( NO) ( NH3),(N0,)](N0,)C1.76Olefins can readily substitute into arenemetal car-bonyls and can sometimes stabilise a cation in the same manner as an extracarbonyl group. n-Mesitylenechromium tricarbonyl reacts with ethylene togive (n-C,H3Me3)Cr(C,H4)(~o)2,77 and metal carbonyl and n-cyclopenta-dienylmetal carbonyl halides react with aluminium halides in the presence ofethylene to give the cations [Mn(CO),(C,H,)] f, [ (n-C,H,)Fe(CO),(C,H,)] +,and [ (n-C,H,)M(CO),(C,H,)] + (M = Mo, W) which can be isolated in the formof stable salts.,,, 78 The z-ally1 complexes (n-C,H,)Fe(CO),(n-C3H4R)(R = H or Me) are protonated by hydrogen chloride or hydrochloric acidto give the propene analogues of the ethylene-iron complex mentionedabove.79 By varying both of the metals in the systems, R,MCl,, TCl,(R = alkyl, M = p-group metal, T = transition metal), which can be usedfor olefin polymerisations, it has been shown that the growing polymer, andhence the initial olefin, is attached to the transition metal.80 Olefin coin-plexes are considered to act as intermediates in reactions in which chloro-ruthenate(I1) solutions act as homogeneous catalysts for the hydrogenation ofolefins 81 and in the Meerwein reaction in which an aryldiazonium halideadds across the double bond of an olefin.82 Dimethylpent-4-enylarsineMe2As*[ CH,],*CH:CH, can act as a chelating agent by co-ordination throughthe arsenic and the double bond, and forms complexes with platinum(n);83however, vinyl sulphides undergo desulphurisation, and the products of thereaction between the vinyl sulphides RS*CH=CH2 and tri-iron dodeca-carbonyl are formulated as (5), a structure in which the vinyl group is actingas a bridge between the two iron atoms by way of a 7t and a u bond, theother half of the bridge being made up by the sulphur-containing residue.84(e) ObeJin compbexes.HMe Meo=c c=oH\ /* //c=q\H ,c=c,c=c' \ (OC),Fe -S J e ( c 0 ) 3 Me Me (6)R (5)Many new complexes of polyenes have been described and these will bementioned only where new principles are involved.A structurd deter-mination on butadieneiron tricarbonyl has confirmed that it is a n-bondcomplex with both double bonds taking part in the co-ordination.In fact,i 8 W. P. GrifEth, J. Lewis, and G. Wilkinson, J., 1961, 775.*"E. 0. Fischer and P. Kuzel, 2. Naturforsch., 1961, 16b, 475.78E. 0. Fischer and K. Fichtel, Chem. Ber., 1961, 94, 1200.7 9 M. L. H. Green and P. Nagy, Proc. Chern. SOC., 1961, 378.8oF. J. Karol and N. L. Carrick, J. Amer. Chem. SOC., 1961, 83, 2654.J. Halpern, J. F. Harrod, and B. R. James, J. Amer. Chcm. SOC., 1961, 83, 753.82 G. N. Schrauzer, Chem. Ber., 1961, 94, 1891.83 H. W. Kouwenhoven, J. Lewis, and R. S. Nyholm, Proc. Chem. Xoc., 1961, 220.84 R. B. King, P. M. Treichel, and F. G. A. Stone, J. Amer. Chem. SOC., 1961, 83,3600SHARP: THE TRANSITION ELEMENTS 113there is complete delocalisation of the n electrons from the formal dienestructure.s5 A new butadiene complex, [ (C4H6)C~(C0)2]2, has been shownto result from the action of butadiene on dicobalt octacarbonyl.86 m- andp-Divinylbenzenes react with iron pentacarbonyl to give bis( tricarbonyliron) complexes. The nature of these is not known, but the stoicheiometrysuggests that the divinylbenzenes are not using their full co-ordinatingcapacity of five double bonds but are co-ordinating through two diene groups.A similar co-ordinating capacity equal to two diene residues is found forvinylcy~loheptatriene.~~ Duroquinone (6) can act as a diene towards nickeland gives bisduroquinonenickel(0) when it reacts with nickel carbonyl.Cyclo-octatetraene displaces one duroquinone residue to give cyclo-octa-tetraeneduroquinonenickel(0).88 A structural determination on norborna-dienepalladium(r1) chloride has shown that both double bonds are co-ordinated to the metal ; 89 in cycloheptatrienemolybdenum tricarbonyl theC=C bonds in the ring have not become delocalised; the methylene group isout of the plane of the other carbon atoms, the carbonyl groups are on the sideof the metal opposite to the seven-membered ring. Cycloheptatrienereacts with iron pentacarbonyl to give cycloheptatrieneiron tricarbonyl ('7)in which the Fe(CO), residue is bonded to two adjacent double bonds, andcyclohepta-l,3-dieneiron tricarbonyl (8). The un-co-ordinated double bondin the cycloheptatriene complex can be readily protonated in acids or canreact with a triphenylmethyl cation to give carbonium ions (9) which arestabilised by co-ordination to the metal.Cyclo-octatetraeneiron tricarbonylis protonated similarly.Q1 Fulvene, with three double bonds, gives a varietyof products when it reacts with iron carbonyls. The two double bondsin the ring can act as a diene system to an Fe(CO), residue, and the iron atomand the remaining double bond can bond to yet another Fe(CO), grouping;alternatively each double bond can co-ordinate separately to Fe(C0)4 groups.6,6-Diphenylfulvene co-ordinates to a Cr(CO), residue by way of the aromaticrings. 92 The structure of cyclo-octatetraenedi-iron hexacarbonyl shows86 0. 8. Mills and G. Robinson, Proc. Chem. Soc., 1960, 421.8g E. 0. Fischer, P. Kuzel, and H. P. Fritz, 2.Naturforsch, 1961, 16b, 138.87 R. B. King and F. G. A. Stone, J . Amer. Chem. Soc., 1961,83,3590; T . A. Manuel,8 8 G.-N. Schrauzer and H. Thyret, J. Amer. Chenz. SOC., 1960, 82, 6420; 2. Natur-89 N. C. Baenziger, J. R. Doyle, and C. Carpenter, Acta Cryst., 1961, 14, 303.slA. Davison, W. McFarlane, L. Pratt, and G. Wilkinson, Chem. and Ind., 1961,553; R. Burton, L. Pratt, and G. Wilkinson, J., 1961, 594; H. J. Dauben, jun., andD. J. Bertelli, J . Amer. Chem. SOC., 1961, 83, 497; G. N. Schrauzer, ibid., p. 2966.s*E. Weiss and W. Hubel, Angew. Chem., 1961, 73, 298; E. 0. Fischer and W.Semmlinger, Naturwiss., 1961, 48, 525.S. L. Stafford, and F. G. A. Stone, ibid., p. 3597.forsch., 1961, 16b, 353.J. D. Dunitz and P. J. Pauling, Helv. Chim.Acta, 1960, 43, 2188114 INORGANIC CHEMISTRYthat the ring is in the form of a chair and that each iron tricarbonyl groupis associated with four carbon atoms in an arrangement (10) very similarto that found for butadieneiron tricarbonyl. Theequivalence of the protons is a dynamic effect.93As mentioned in last year’s Report, polyenes canundergo isomerisations with metal carbonyls andthen may give complexes which are apparentlyderived from olefins in which there are conjugateddouble bonds. Thus the two isomeric iron tri-carbonyl complexes which result from the inter-action of tri-iron dodecacarbonyl and cyclo-octa-trienes are complexes derived from the olefins bicyclo[4,2,0]octa-2,4-dieneand cyclo-octa- 1,3,5-triene ; 1,4-~yclopentadiene yields complexes that arederived from cyclopenta- lY3-diene ; and lY4-dihydromesitylene gives com-plexes derived from 1 ,3-dihydrome~itylene.~*The major recent advances in the study of olefin complexes have comein the recognition of further “ enyl ” derivatives of the transition metalsin which odd numbers of electrons are donated to the metal atom.Manyof these complexes were known previously but have now been re-formulated.Propenyl derivatives of manganese, cobalt, nickel, palladium, and platinum,in which the metal is further bonded to carbonyl, n-cyclopentadienyl, halide,phosphine, and other ligands, have been described. 5 9 96 Nuclear magneticresonance studies on solutions of some of these propenyl derivatives indimethyl sulphoxide suggest that in this polar solvent the complexes revertto classical o-bonded organometallic structures, the co-ordination spherebeing completed by the solvent. 96 The perfluoropropenyl group forms onlyo-bonded compounds.97 The “ enyl” group can be part of a ring, andformally the resonance and co-ordination stabilised carbonium ions describedabove 91 are part of this series.The complex which results from theaction of cyclopentadiene on nickel carbonyl is now recognised as n-cyclo-pentadienyl-n--cyclopentenylnickel( 11) and similar n-cyclopentenyl andn- cyclohexenyl derivatives have been prepared for nickel and palladium byreaction between the appropriate Grignard reagent and a metal halide orby interaction of dienes and metal carbonyl~.~~ The action of a mixtureof carbon monoxide and hydrogen on di-n-cyclopentadienylchroinium(n)gives n-cyclopentadienyl-n-cyclopentenylchromium(rr) dicarbonyl.lOO Theg3 B.Dickens and W. N. Lipscomb, J . Amer. Chem. SOC., 1961, 83, 489.s4T. A. Manuel and F. G. A. Stone, J . Amer. Ch,em. Soc., 1960, 82, 6240; J. E.Arnet and R. Pettit, ibid., 1961, 83, 2954; R. B. King, T. A. Manuel, and F. G. A.Stone, J . Inorg. Nuclear Chem., 1961, 16, 233; cf. Ann. Beports, 1960, 57, 146.95W. R. McClellan, H. H. Hoehn, H. N. Cripps, E. L. Muettertiss, and B. W.Howk, J . Amer. Chem. SOC., 1961, 83, 1601; R. F. Heck and D. S. Breslow, ibid., p.1097; E. 0. Fischer and R. D. Fischer, 2. Naturforsch., 1961, 16b, 475; E. 0. Fischerand G. Barger, ibid., pp. 77, 702; Chem. Ber., 1961, 94, 2409; H. P.Fritz, ibid., p. 1217;B. L. Shaw and K. Sheppard, Chem. and Ind., 1961, 517; R. F. Heck, J. C. W. Chien,and D. S. Breslow, ibid., 1961, 986.96 J. C. W. Chien and H. C. Dehm, Chem. and Ind., 1961, 745.97 R. B. King, S. L. Stafford, P. M. Treichel, and F. G. A. Stone, J . Amer. Chem.Sm., 1961, 83, 3604.99 D. Jones, G. W’. Parshall, L. Pratt, and G. Wilkinson, Tetrahedron Letters, 1961,48; E. 0. Fischer and H. Werner, ibid., p. 17; M. Dubeck and A. H. Filbey, J . Amer.Chem. Xoc., 1961, 83- 1357.Fe(C0)3Fe( CO) 3 4SHARP: THE TRANSITION ELEMENTS 115compound previously regarded as n-benzenecyclopentadieneiron(0) is nowregarded as n-cyclohexadienyl-n-cyclopentadienyliron(n) and n- 1 -en&-phenylcyclohexadienyl derivatives are obtained by the action of phenyl-di-n-benzenerhenium(1) cation is converted by hydrides to n-cyclohexadienyl-z-benzenerhenium(1) but reduction of the di-n-benzeneruthenium(1r) cationgives only the olefin complex (~-C,H,)RU(C,H,).~~~ In an unusual reactionwhich involves ring opening, n-tetramethylcyclobutadienenickel dichloridereacts with sodium cyclopentadienide to give n-cyclopentadienyl-n-dihydro-tetramethylindenylnickel(n) (1 1) .lo2 Butadieneiron tricarbonyl reacts withlithium on [ (n-C,H,)Mn(Co),][C1o*] and [ (n-C,H,)(n-C,H,)Fe]Br,.Thehydrogen chloride to give (12). Only one isomer is formed and it is suggestedthat the geometry of the original butadiene complex is retained in then-ally1 complex so that the methyl group is always in one position withrespect to the metal.lo3( f ) Acetylene complexes and reactions of transition-metal compounds withacetylenes.There will be no discussion in this section of the reactions ofacetylenes which have only been postulated to go by may of acetylenecomplexes. n-Cyclopentadienylmanganese tricarbonyl reacts with diphenyl-acetylene to give (n-C,H,)Mn(Ph*C=C*Ph)(CO)2 in which the acetylene isreplacing a carbonyl group in one co-ordination position.lo4 As mentionedin previous Reports a-aryl derivatives of the transition metals can tri-merise acetylenes to benzenoid compounds. After application of diphenyl-manganese(rr) or dimesitylcobalt(1r) to trimerise but-%yne, n-hexamethyl-benzene complexes of these metals can be is01ated.l~~ A crystal-structuredetermination has confirmed that the product from the reaction betweenmcyclopentadienylcobalt dicarbonyl and but-2-yne is n-cyclopentadienyl-tetramethylcyclopentadienonecobalt(I). The carbonyl group in the cyclo-pentadienone ring is tipped away from the metal; all the C-C bonds are ofequal length implying extensive delocalisation of the double bonds.Alarge range of products has been isolated as the result of reactions betweenacetylenes and cobalt carbonyl derivatives. The nature of most of theproducts is unknown; many can be broken down to give aromatic C, ringsystems. Some of the complexes are formulated as derivatives of cyclopen-tadienones and some have been regarded as containing a cyclobutadienelooE. 0. Fischer and K. Ulm, Chem.Ber., 1961, 94, 2413.lolD. Jones and G. Wilkinson, Chem. and Ind., 1961, 1408.lozR. Criegee and P. Ludwig, Chem. Ber., 1961, 94, 2038.Io3F. J. Impastato and K. G. Ihrman, J . Amer. Chem. SOC., 1961, 83, 3726.lo4 W. Strohmeier and D. von Hobe, 2. Naturforsch., 1961, 16b, 402.lo6M. Tsutsui and H. Zeiss, J . Amer. Chem. SOC., 1961, 83, 825; cf. Ann. Reports,lo6L. F. Dahl and D. L. Smit,h, J . Amer. Chem. Xoc., 1961, 83, 752.1959, 56, 142; 1960, 57, 148116 INORGANIC CHEMISTRYring system as a bridge between two cobalt atoms. Hg[Co(CO),], reactswith Me,C*CrCH to give the complex (13) in which the acetylenes havetrimerised in an unsymmetrical manner. On degradation this complex gives( R = CMe3)1,2,4-tri-t-butylbenzene.1°7 Dimethyl acetylenedicarboxylate acts as adienophile towards di-n-cyclopentadienylnickel(11) and gives 2-n- (2,3-bismeth-oxycarbonylnorborna-2,5-dien-7-yl)-n-cyclopentadienylnickel( rr) (14).l08To judge from this reaction and from the details of some of the structureswhich have been published this year, considerable work needs to be doneto establish the reasons why the double bonds in polyene complexes some-times behave as if they were independent and sometimes as if they wereconjugated.(g) Complexes with aromatic systems. 4-Bromo- lY2,3,4-tetraphenylbuta-cis-1 ,cis-3-dienyldimethyltin bromide (16) [prepared by the action of brominePh PhP h O P h BrMe2SnCPh = CPh-CPh=CPhBrMe Me 2"\ (IS) 0 6 )on 1 ,l-dimethy1-2,3,4,5-tetraphenylstannole (15)] reacts with nickel bromideto give n-tetraphenylcyclobutadienenickel dibromide.The uncomplexedcyclobutadiene system may have a triplet ground state and evidence for thisis found in the transitory green colour observed during the reaction and inthe great avidity of the unknown intermediate for oxygen.lo9 Detailedinfrared and Raman spectral studies of dicyclopent adienylmagnesium indi-cate that this should be considered as a true sandwich compound withconsiderable covalent character in the metal-ring bond. This immediatelybroadens the field of possible sandwich compounds to include many deriva-tives of non-transition metals. 110 Di-n-cyclopentadienyltitanium dichlorideis reduced by di-isobutylaluminium chloride to the deep-violet compound(n-C,H,)TiCl,. It is insoluble in all hydrocarbons but gives a blue solutionin acetonitrile; it is not a catalyst for the polymerisation of ethylene.ll1Mixed halogenoalkoxy-n-cyclopentadienyl derivatives of titanium( 1v) can belo' U.Kriierke, C. Hoogzand, and W. Hiibel, Chem. Ber., 1961,94,2817; U. Kriierkeand W. Hiibel, ibid., p. 2829.lo8M. Dubeck, J. Amer. Chem. SOC., 1960, 82, 6193.loeH. H. Freedman, J . Amer. Chem. Soc., 1961, 83, 2194, 2195.110 E. R. Lippincott, J. Xavier, and D. Steele, J . Amer. Chem. Soc., 1961, 83, 2262.lXIP. D. Bartlett and B. Seidel, J . Amer. Chenb. SOC., 1961, 83, 581SHARP: THE TRANSITION ELEMENTS 117obtained by the action of sodium cyclopentadienide on the titanium( IV)halogenoalkoxides.112 Niobium and tantalum pentahalides react withsodium cyclopentadienide to give violet compoundswhich are formulated (17) with two n-cyclopentadienylrings and two a-cyclopentadienyl rings.l13 A new cyclo-pentadienyl derivative, [ (C,H,),Tc],, has been synthesisedby the action of sodium cyclopentadienide on tech-netium tetrachloride. It is different in type from knownmanganese and rhenium derivatives and must probablybe formulated with a metal-metal bond as is presumedfor the carbonyl.114 Further n-cyclopentadienyl derivatives containingmetal-metal bonds linking two different elements have been synthesised,(~-C,H,)Mo(CO),Na and Mn(CO),Na react with (n-C,H,)Fe(CO),I to give(n-C,H,)Mo(CO),Fe(n-C,H,)( CO), and Mn( CO),Fe(n-C,H,) (CO),, respectively.Di-n-cyclopentadienylnickel reacts with iron pentacarbonyl to give(n-C,H,)Ni(CO~Fe(n-C,H,)(CO), in which there are almost certainly bridgingcarbonyl groups in addition to the metal-metal b0nd.1~5 Chloro-n-cyclo-pentadienyliron dicarbonyl gives cationic species [ (n-C,H,)Fe( CO),] + and[(n--C5H5)Fe(CO),(Ph3M)]+ (M = P, As, Sb) under the influence of carbonmonoxide or a Ph,M ligand.Reduction of the tricarbonyl species withsodium borohydride gives (n-C,H,)Fe(CO),H, but the triphenylphosphine-substituted cation gives dicarbonylcyclopentadienetriphenylphosphineiron-(0).116 Fulvenes and azulenes react with ferrous salts in the presence oflithium aluminium hydride to give substituted ferrocenes, and the samegeneral method can be used for the preparation of n-cyclopentadienyl deri-vatives of other elements.l17 Solvolysis studies on ferrocenyl-, rutheno-cenyl-, and osmocenyl-methyl acetates indicate a high stability for theresulting intermediate carbonium ions and there is a strong possibility ofdirect bonding between the metal atom and the cationic carbon.118 Eachmember of the series (n-C,H,),Fe, (n-C,H,),Ru, and (n-C,H,),Os is oxidisedin a different manner. Ferrocene is oxidised by a one-step one-electronoxidation, ruthenocene by a two-step one-electron oxidation, and osmoceneby a one-step two-electron oxidation.As is to be expected, the actualoxidation potentials depend upon the electron-withdrawing power of thesubstituents in the ring systems. 119 n-Cyclopentadienylrhodium dicarbonylhas been prepared by the action of sodium cyclopentadienide on[Rh(CO),Cl],.120The n-arene-transition metal complexes have been reviewed. 121 InA. N. Nesmeyanov, 0. V. Nogina, and A. M. Berlin, Dolclady Akad. NaukS.S.S.R.,QPpyMw( ' 7 )1960, 134, 607.ll3E. 0. Fischer and A. Treiber, Chem,. Ber., 1961, 94, 2193.114D. K. Huggins and H. D. Kaesz, J . Amer. Chew&. SOC., 1961, 83, 4471.115 R. B. King, P. M. Treichel, and F. G. A. Stone, Ghem and Ind., 1961, 747;116 A. Davison, M. L. H. Green, and G. Wilkinson, J . , 1961, 3172.11' G. R. Knox and P. L. Pauson, J . , 1961, 4610; G. R. Icnox, J. D. Munro, P. L.l18E. A. Hill and J. H. Richards, J . Amer. Chem. Soc., 1961, 83, 3840, 4216.llD T. Kuwana, D. E. Bublitz, and G. Hoh, J . Amer. Chem. SOC., 1960, 82, 5811.120E.0. Fischer and K. Bittler, 2. Naturforsch., 1961, 16b, 225.121 E. 0. Fischer and H. P. Fritz, Angew. Chern., 1961, 73, 353.J. F. Tilney-Bassett, Proc. Chena. SOC., 1960, 419; cf. Ann. Reports, 1960, 57, 149.Pauson, G. H. Smith, and W. E. Watts, J., 1961, 4619118 I N O R G A N I C CHEMISTRYspite of the structure which shows alternate short and long C-C bonds inthe rings, di-n-benzenechromium still retains considerable aromatic character,as is shown by its dimetallation by pentylsodium.122 Biphenylene formscomplexes with two and one molybdenum tricarbonyl residues; in bothcases the metal is bonded to the six-membered ring systems and not to thefour-membered ring.123 The di-n-benzenetechnetium(1) cation has beenobtained by irradiation of di-n-benzenemolybdenum with neutrons :n, YMo(C6H6)2 4 [Tc(C6H6),lf;it can be isolated as the insoluble tetra~heny1borate.l~~ Triphenylmethylfluoroborate will abstract hydride ion from z-cyclopentadienylcyclohexa-dienecobalt(1) to give the [ (~-C,H,)(~-C,H,)CO]~+ cation.125 A series ofcomplexes in which different functional groups in an organic molecule areco-ordinated to different metal atoms have been prepared.Thus 1,4-diphenylbutadiene gives mono- and di-chromium tricarbonyl derivatives andP h O - Phthese react further with iron pentacarbonyl to give the complexes (18) and(19). The possibilities of this type of reaction appear almost endless andvariations can be effected by use of olefin, acetylene, cyclopentadienyl, andaryl derivatives.126 A solution of sodium hexacarbonylvanadate( -I) indiethylene glycol dimethyl ether reacts with cycloheptatriene to give thegreen diamagnetic compound n-cycloheptatrienylvanadium tricarbonyl.Tropylium bromide will not give this derivative dire~t1y.l~~Organometallic Compounds of the Transition Elements.-The mostnotable feature of this section of inorganic chemistry has been the rapiddevelopments in the knowledge of the fluoroalkyl derivatives of the transi-tion elements.It is now clear that these compounds are much more stablethan the corresponding hydrocarbon compounds. Metal hydrides will addacross the double bond of a perfluoro-olefin to give compounds of the typeHCF,*CF,*Mn(C0)5 and HCF,*CP,*MO(CO),(~-C,H,).~~~ Perfluoroacyl de-rivatives of the groupings Mo(CO),(n-C,H,), Mn( CO),, and )Co(CO), resultfrom the action of the acyl chloride or anhydride on an appropriate alkali-metal salt; they lose carbon monoxide when heated and are convertedinto the corresponding perfluoroalkyl derivatives.The reaction betweentrifluoroiodomethane and sodium pentacarbonylmanganate( -I) givesMn(Co)51,97, 129 but perfluoroalkyl derivatives of iron and cobalt can be122E. 0. Fischer and H. Brunner, 2. Naturforsch., 1961, 16b, 406.123 J. Chatt, R. G. Guy, and H. R. Watson, J., 1961, 2332.124 F. Baumgartner, E. 0. Fischer, and U. Zahn, Chem. Ber., 1961, 94, 2198.125E. 0. Fischer and R. D. Fischer, 2. Naturforsch., 1961, IGb, 556.126M. Cais and M. Feldkimel, Tetrahedron Letters, 1961, 440, 444; J.F. Tilney-Bassett, J., 1961, 577; T. A. Manuel, S. L. Stafford, and F. G. A. Stone, J . Amer. Chew.Soc., 1961, 83, 3597.I27R. P. M. Werner and S. A. Manastyrskyj, J . Amer. G'hem. SOC., 1961, 83, 2023.128R. B. King, P. M. Treichel, and F. G. A. Stone, Proc. Chem. SOC., 1961, 69.129T. H. Coffield, J. Kozikowslri, and R. D. Closson, Vth Internat. Conf, Co-ordSHARP: THE TRANSITION ELEMENTS 119prepared by the action of trifluoroiodomethane and its higher homologues.Iron pentacarbonyl gives compounds RpFe(CO),I and [R,Pe(CO),I], andn-cyclopentadienylcobalt dicarbonyl gives (n-C5H,)Co(CO)RFI.* The brownsolutions that result from the action of sodium on a solution of tri-irondodecacarbonyl in tetrahydrofuran react with perfluoroacyl chlorides to givederivatives (R,),Fe(CO),, similar to the heterocyclic compound describedlast year.A similar compound (C,F,),Co(CO)(n-C,H5) results from theact ion of tetra fluoroet h ylene on TC - c y clo pent adien y lco balt dicarb on yl .97 5 130Further evidence that the first step in hydroformylation and in olefin-isomerisations that are catalysed by cobalt carbonyl hydride is the additionof the hydride across the double bond of the olefin, has come from isolationof the actual intermediate organometallic compounds as their triphenyl-phosphine adducts. A unified mechanism has now been advanced for bothof these reacti0ns.1~1 Metal ions can interact with organic free radicals togive organometallic derivatives which may ultimately break down to thedimer of the radical.An aqueous solution of phenyl t-butyl hydroperoxidereacts with chromous sulphate to give the [Ph*CH,Craq.I2 + cation identicalwith that prepared by the action of benzyl chloride on chromous perchlor-ate. The carbonylation of organometallic derivatives has been extendedto the trans-[MXR(PEt,),] complexes (M = Pd, Pt; R = alkyl or aryl).The palladium derivative gives an acyl compound at atmospheric pressure ;higher pressures must be used for the platinum compound. The carbonylcompounds that are presumably present as intermediates have not beeni~olated.13~ 2,2’-Bipyridyl (bipy) and dimeric acetylacetonatotrimethyl-platinum react to give the compound Me,Pt(Me*CO-CH*CO*Me)(bipy) inwhich the platinum atom is in octahedral co-ordina-atoms of the bipyridyl, and the active methylene MeC\H,CMe Ccarbon of the p-diketone (20).The carbonyl oxygen Me= I -,.pieatoms are not co-ordinated to the metal and the “P t -.Cyclo-octatetraeneplatinum(11) iodide reacts withpounds R,Pt(C&,)PtR, in which the two platinumatoms are bridged by the cyclic olefin.and other strongly n-bonding ligands.l35tion from three methyl groups, the two nitrogen 0 9. ,diketone is acting as a monodentate ligz~nd.13~ /Me‘\Grignard reagents to give the organometallic com- - I (20)The olefin is displaced by phosphinesChem., London, 1959, The Chemical Society, London, 1960, p. 126; H. D. Kaesz,R. B. King, and F. G. A. Stone, 2. Naturforsch., 1960, 15b, 763; W. Hieber, W. Beck,and E. Lindner, ibid., 1961, 16b, 229; W.R. McClellan, J . Amer. C h m . SOC., 1961, 83,1598; W. Beck, W. Hieber, and H. Tengler, Chem. Ber., 1961, 94, 862.l30 T. D. Coyle, R. B. King, E. Pitcher, S. L. Stafford, P. M. Treichel, and F. G. A.Stone, J . Inorg. Nuclear Chem., 1961, 20, 172; R. B. King, P. M. Treichel, and F. G. A.Stone, J . Amer. Chem. SOC., 1961, 83, 3593; cf. Ann. Reports, 1960, 57, 150.131 R. F. Heck and D. S. Breslow, J . Amer. Chem. SOC., 1961, 83, 4023.132 J. K. Kochi and F. F. Rust, J . Amer. Chem. SOC., 1961,83,2017; cf. F. A. L. Anetand E. Leblanc, ibid., 1957, 79, 2649.133G. Booth and J. Chatt, Proc. Chem. SOC., 1961, 67.134A. G. Swallow and M. R. Truter, Proc. Chenz. SOC., 1961, 166.135 J. R. Doyle, J. H. Hutchinson, N. C. Baenziger, and L. W.Tresselt, J . Amer.Chem. SOC., 1961, 83, 2768.* Rp = perfluoroalkyl120 INORGANIC CHEMISTRYMolecular Hydrides of the Transition Elements.-A study of the visibleand ultraviolet spectra of the complexes trans-[RuXY (C,H,(PMe,),f ,](X = Y = C1, Br, I, CN; X = H, Me, Ph, p-Me*C6H4, Y = C1) has shownthat the hydride and organometallic radicals have large ligand-field strengthsbut that these field strengths are less than that of the cyanide i0n.136ReX,(PR,), derivatives are reduced by sodium borohydride in ethanol toReH,( PR,),(Et*OH),. The solvating ethanol is lost on crystallisation frombenzene, and the hydride will then react with more triphenylphosphine togive ReH,(PR,),, an air-stable hydride which is converted into the paramag-netic complexes ReX,(PR,), by HX (X = C1, Br).137 Various papers havegiven further information on the products (hydrides, carbonyls, carbonylhydrides, or complexes of the Group V ligands) from the reactions of transi-tion-metal halides with alcohols in the presence of suitable ligands.Thereactions are generally carried out in the presence of a base but this appearsto be unnecessary when the process takes place at 100" or above. Inaddition to the complexes reported previously, new derivatives of the types,IrX(CO)L,, and II-H~X(,-~)L, (n = 1 or 2; X = C1 or Br; L = PPh,,AsPh,, or SbPh,) have now been is01ated.l~~ When sodium borohydrideis used to reduce transition-metal halide derivatives the products are gener-ally metal hydrides rather than salts of the metal in lower oxidation states.trans-Bisethylenediaminedichlororhodium(1II) chloride gives a pale brownsolution containing the [Rh1Ien2HC1] + cation.The other ligands in thisgrouping are not generally recognised as giving rise to strong n bondingand n bonding does not appear to be necessary to confer stability on transi-tion-metal hydrides. 139 Iridium tribromide and triphenylphosphine reactwith sodium borohydride to give two products of the formula IrH,L,,which can also be obtained more indirectly by the action of lithium alumi-nium hydride on IrHCl,L, in tetrahydrofuran. They are presumablystereoisomers, and they give IrH,L,X (X = acetate, hydrogen oxalate, hydro-gen malonate, or hydrogen tartrate) with acids and react with perchloric acidto give IrH,L,C10,, a compound which probably contains an [IrH,L,]+cation.140 Potassium t e trac hloro pla tinate ( II) reacts with trip hen y 1 p hosp hinein the presence of ethanol and potassium hydroxide to give compoundswhich are now recognised as hydrides PtH,L,, PtH,L,, and PtH,L,;the same products result from the reduction of bistriphenylphosphineplati-num(n) iodide in ethanol.(R = Ph, Me), prepared by reduction of the corresponding chlorides withsodium borohydride or sodium naphthenide, are true compounds of zero-positive platinum.141[RuC12(CO)2(PR3)]2~ RuBr3(C0)(PR3)2, [RuC12(Co)(AsR3)]3~ IrH2C1(PR,)3,However, the complexes Pt( R,P*CH,*CH,-PR,)136 J. Chatt and R. G. Hayter, J., 1961, 772.137M. Freni and V. Valenti, Gazzetta, 1961, 91, 1357.138 J.Chatt and B. L. Shaw, Chem. and Id., 1961, 290; L. Vaska, ibid., p. 1402;J . Amer. Chem. SOC., 1961, 83, 756; L. Vaska and J. W. DiLuzio, ibid., pp. 1262, 2784;cf. Ann. Reports, 1960, 57, 152.139 G . Wilkinson, Proc. Chem. SOC., 1961, 72.140 L. Malatesta, M. Angoletta, A. ArAneo, and F. Canziani, Angew. Chem., 1961,73, 273; R. G. Hayter, J . Amer. Chem. SOC., 1961, 83, 1259.141 J. A. Chopoorian, J. Lewis, and R. S. Nyholm, Nature, 1961, 190, 529; J. Chattand G. A. Rowe, ibid., 1961, 191, 1191; cf. L. Malatesta and C. Cariello, J., 1958, 2323SHA4RP: THE TRANSITION ELEMEPU’TS 121Scandium, Yttrium, and the Rare Earths.-A new book has been pub-lished on the chemistry of yttrium and scandium,14z and the chemistries ofthe rare-earth and actinide sulphides have been reviewed.143 The hydroxidesof the heavier lanthanides are amphoteric, and salts Na,M(OH), (M = Yb, Lu)can be prepared by the action of concentrated sodium hydroxide on thehydroxides in an a~toclave.14~ High-temperature fluorination of mixturesof sodium chloride and praseodymium chloride gives NaPrF, in additionto the previously known Na,PrF6.145 GdCl,,GH,O contains [Cl,Gd( OH,),] +eight-co-ordinate cations which have a completely unsymmetrical configura-tion. The actual structure appears to be a common one amongst the rare-earth and actinide halide h e ~ a h y d r a t e s .~ ~ ~ More chlorodiborohydrides,MC1(BH4), (M = Gd, Tb, Dy, Er, and Tb), have been prepared by the reac-tion between the appropriate metal trichloride and lithium borohydride intetrahydrofuran. The action of heat on the gadolinium and terbium corn-pounds gives MC1( B,H,) derivatives whilst the samarium wmpound givesSm,C1,( B,H6). It is possible that these compounds contain (B,H,) - ions.147The reduction of lanthanide halides with lanthanide metals continues to bestudied. Neodymium trichloride gives various products ; neodymium di-chloride has the samarium dichloride structure and Nd11.95 is isomorphouswith samarium dibromide so that it appears definite that these compoundscontain dipositive neodymium. Lanthanum, cerium, and praseodymiumdi-iodides have been prepared; they are all isostructural and have a metallicappearance with a high conductivity in the solid state. It is suggested thatthey should be formulated M3+e-(I-),.148The Actinides.-The fluorides of the actinide elements have beenreviewed.149 Reduction of a solution of tripositive actinium in citric acidgives an amalgam; by analogy with the properties of the rare-earth ele-ments, this is considered as evidence for the existence of a dipositive oxida-tion state for this element.150 The system caesium fluoride-thorium tetra-fluoride is as complex as the similar systems involving other alkali-metalfluorides, and phases in which the components have ratios of 3 : 1, 2 : 1,1 : 1, 2 : 3, 1 : 2, 1 : 3, and 1 : 6 are formed;151 alkali chlorides react withthorium tetrachloride to give the phases MThCl,, M,ThCl,, and M,ThCl,(applicable to all M except for Na3ThC1,).152 The chemistry of prot-actinium has been reviewed.lS3 An electrometric study has been made142 R.C. Vickery, “ The Chemistry of Yttrium and Scandium,” Pergamon, London,143 G. V. Samsonov and S. V. Razikovskaya, Uspelchi Iihim., 1961, 60 [ZS].144 B. N. Ivanov-Emin and L. A. Nisel’son, Zhur. neorg. Khim., 19C0, 5, 1921 [937].la5L. B. Asprey and T. K. Keenan, J. Inorg. Nuclear Chem., 1961, 16, 260; cf.R. Hoppe, Angew. Chern., 1959, 71, 457.146 M. Marezio, H. A. Plettinger, and W. H. Zachariasen, Acta Cryst., 1961, 14, 234.14’ K. Rossmanith and E. Muckenhuber, Monatsh., 1961, 92, 600; K. Rossmanith,&id., p. 768; cf. A. Brukl and K. Rossmanith, ibid., 1959, 90, 481.14* L. F. Druding and J. D. Corbett, J. Amer. Chem. SOC., 1961, 83, 2462; J.D. Cor-bett, L. F. Druding, and C. B. Lindahl, J. Inorg. Nuclear Chem., 1961, 17, 176.laON. Hodge, Adv. Fluorine Chem., 1961, 2, 138.150 G. BouissiAres, M. Haissinsky, and Y. Legoux, Bull. SOC. chim. France, 1961, 1028.I5lR. E. Thoma and T. S. Carlton, J . Inorg. Nuclear Chem., 1961, 1’7, 88.152 V. I. Ionov, B. G. Kovshunov, V. V. Kokorev, and I. S. Morozcv, Izwest. Vysshikh153V. A. Mikhailov, Uspekhi Khim., 1960, 882 14191.1960.Ucheb. Zavedenii, Tsvetnaya Met., 1960, 3, 102122 IN 0 RG AN I C CHEMISTRYof the hydrolysis of the uranyl ion and it has been shown that in sodiumsulphate solution sulphato-groups are closely associated with the condenseduranyl residues ; core-link complexes of the type {UO,[ ( 0H),UO,ln j 2 + arefound in s01ution.l~~ Oxygen exchange between water and the uranyl ionis catalysed by the UO,+ ion which undergoes exchange with both activatedwater and the uranyl ion;155 the oxygen liberated during the decompositionof U04,2H,0 originates in the metal peroxide which is thus established asa true peroxide; a new uranium peroxide hydrate, U0,,4H20, has beenfound in this system.156 Previous attempts to prepare uranium(1v) nitratein aqueous and non-aqueous solvents have given oxy-species but it hasnow been found that salts UX,,nCH,*CO-NMe, (X = C1, NO,) can be pre-pared in dimethylacetamide and that addition of an ionic nitrate to a ura-nium(1v) solution in a mixture of nitric acid and sulphamic acid gives com-plex salts M,U(NO,), (M = Cs, Et4N).l5' A series of new uranium selenides,Use,, U3Se5, U,Se,, U,Se4, have been prepared by the action of hydrogenand selenium on uranium tetrachloride; UO, and UTe, interact to give anoxytelluride, UOTe.158 Although all previous work has indicated that thecompound formed by uranium hexafluoride and sodium fluoride is 3NaF,UF,,fluorine-exchange studies are in favour of 2NaF,UF6 as the stable adduct.159Plutonium trifluoride gives a 1 : 1 adduct with sodium fluoride but thereis no compound formation in the system LiF-PuF3;160 rubidium chloridegives 1 : 2, 2 : 1, and 3 : 1 adducts with plutonium trichloride, czesiumchloride gives 1 : 2 and 3 : 1 adducts.161 Americium(m) hydroxide isoxidised by hypochlorite to the tetrapositive hydroxide which will reactwith aqueous ammonium fluoride to give a pink-red solution of an ameri-cium(rv) complex fluoride. This is the first observation of an americium(rv)compound in solution; on acidification there is disproportionation to anamericium(m) and an americium(v) or americium(vr) species.162 Ascurium(1v) fluoride oxidises the ammonium ion, ammonium fluoride cannotbe used to prepare a curium(1v) solution but curium tetrafluoride will dissolvein a solution of czesium fluoride to give a fairly stable curium(1v) s01ution.l~~Titanium, Zirconium, and Ha€nium.-The organic chemistry of titaniumhas been reviewed with particular reference to alkoxides and the organo-metallic intermediates used as Ziegler-type catalysts. l G 4 Potassiumcyanide reacts with titanium tribromide or hexa-amminetitanium(II1)154A. Peterson, Acta Chem.Xcand., 1961, 15, 101.155G. Gordon and H. Taube, J. Inorg. Nuclear Chem., 1961, 16, 272.156 G. Gordon and H. Taube, J. Inorg. Nuclear Chem., 1961, 16, 268; L. Silvermanand R. A. Sallach, J. Phys. Chem., 1961, 65, 370; T. Sato, Naturwiss., 1961, 48, 668.157K. W. Bagnall, P. 8. Robinson, and M. A. A. Stewart, J., 1961, 4060.158 P. Khodadad, Bull. SOC. chirn. France, 1961, 133; W. Trzebiatowski, J. Niemier,and A. Sepichowska, Bul. Acad. polon. Sci., Ser. Sci. chim., 1961, 9, 373.159 I. Sheft, H. H. Hyman, R. M. Adams, and J. J. Katz, J. Amer. Chem. Xoc., 1961,83, 91.160 C. J. Barton, J. D. Redman, and R. A. Strehlow, J. Inorg. Nuclear Chem., 1961,20, 45; C. J. Barton and R. A. Strehlow, ibid., 1961, 18, 143.161R. Benz and R.M. Douglass, J. Phys. Chern., 1961, 65, 1461.16zR. A. Penneman, J. S. Coleman, and T. K. Keenan, J. Inorg. Nuclear Chem.,1961, 17, 138; L. B. Asprey and R. A. Penneman, J. Amer. Chem. SOC., 1961, 83,2200.163 T. K. Keenan, J. Anaer. Chem. SOC., 1961, 83, 3719.1641. Shiihara, W. T. Schwartz, jun., and H. W. Post, Chem. Rev., 1961, 631, 1SHARP: THE TRANSITION ELEMENTS 123bromide to give a complex K,Ti(cN),,BKCN; this appears to be the fistknown complex cyanide of t i t a n i u m ( ~ ~ ~ ) . ~ ~ ~ Complexes MCl,,D (M = Ti)and MCI4,2D (M = Ti, Zr, Hf, V) are formed by reaction between o-phenyl-enebisdimethylarsine and Group IV tetrahalides. TiCl,,BD contains an eight-co-ordinated titanium atom, the co-ordination arrangement being similarto that found for the [Mo(CN),]4- ion in the solid state; it is the first exampleof an eight-co-ordinate metal atom in the first transition series althoughseven-co-ordinate manganese and iron species have been reported this year(pp. 127, 128) and have previously been assumed as intermediates in reac-tions.166 By contrast, titanium(1v) has been shown to have tetrahedralco-ordination by oxygen in the titanium garnets M,TiO, (M = Sr, Ba).167Various mixed-metal oxides containing titanium in oxidation states lowerthan four have now been described.Hydrogen reduces Na2Ti,07 a t 950"to a blue-black titanium oxide bronze Na,TiO, (x -0.2)) and the potassiumsalt can be prepared similarly. Titanium and manganese dioxides reactat 1400" to give the black spinel Mn11Ti11120,.168 An oxychloride, TiOCl,,results from the action of chlorine monoxide on titanium tetrachloride ; itgives adducts TiOC12,2L with pyridine and with phosphorus oxychloride,and complex chlorides M2TiOC14,H,0 (M = Cs, Rb) derived from it canbe isolated from solutions of titanium dioxide in hydrochloric a~id.16~ Thecompounds MTiIJC1,, M2TiI1C1, (M = Rb, Cs), M,TilIICI, (M = Na, K, Rb),and MTi111C14 (M = Rb, Cs) have been identified in the various systemsbetween alkali-metal chlorides and titanium chlorides.17* Potassium chlor-ide, titanium tetrachloride, and phosphorus oxychloride react to give thecompound KTiCl,,POCl, which is an electrolyte in suitable solvents andappears to contain the [TiCl,,OPCl,]- anion.171 Titanium and zirconiumtetrachlorides give monomeric acetylacetonates, TiCl,(acac), and ZrCl( acac),(Hacac = acetylacetone) by direct reaction with acetylacetone.172 Ammo-nolysis of hexachloro- and hexabromo-titanates( ~ v ) proceeds in a similarmanner to that of the tetrahalides, two Ti-X bonds generally being broken;in the ammonolysis of hexachlorozirconates(rv) only one Zr-C1 bond isbroken.The products are mixtures but portions are generally soluble inliquid ammonia, presumably because of the formation of amido-species asani01-1.s.l~~ Titanium dibromide, with the cadmium iodide structure, canbe prepared by reduction of the tetrabromide by metallic titanium.174The tetraoxalatozirconium( IV) anion has a dodecahedra1 configuration about165H.L. Schliifer and R. Gotz, 2. anorg. Chem., 1961, 309, 104.166 R. J. H. Clark, J. Lewis, R. S. Nyholm, P. J. Pauling, and G. B. Robinson,167 J. A. Bland, Acta Cry8t., 1961, 14, 875; P. Tarte, Nature, 1961, 191, 1002.lssA. D. Wadsley and S. Andersson, Nature, 1961, 192, 551; A. Lecerf and A.169 K. Dehnicke, 2. unorg. Chern., 1961,309,266; I. S. Morozov and G. M. Toptygina,l T O P. Ehrlich and R. Schmitt, 2. u w g . Chem., 1961, 308, 91; B. F. Markov andI7lV. Gutmann and F. hlairinger, Monatsh., 1961, 92, 720.172D. M. Puri and R. C. Mehrotra, J. Less Common Metals, 1961, 3, 247.lT3 G. W. A. Fowles and D. Nicholls, J., 1961,95; J. E. Drake and G. W. A. Fowles,J . Inorg. Nuclear Chem., 1961, 18, 136; J . Less Common Metals, 1961, 3, 149.174P.Ehrlich, W. Gutsche, and H.-J. Seifert, 2. anorg. Chem., 1961, 312, 80.Nature, 1961, 192, 222.Hardy, Compt. rend., 1961, 252, 131.Zhur. neorg. Khim., 1960, 5, 2518 [1218].R. V. Charnov, Ukrain. khim. Zhur., 1961, 27, 34124 INORGANIC CHEMISTRYthe metal atom, a configuration which is as probable as the square anti-prism for eight-co-ordinated species.17, A detailed study has been madeof the hydrolysis products of zirconium tetrafluoride and some fluorozir-conates(1v) but the products are complex and their full structures are not yetknown. Acid hydrolysis of fluorozirconates gives compounds of the typeK1.5H0.5Zr2F80, and in alkaline solution KZrF,( H,O) is hydrolysed toKZrF,O by way of KZrF,(OH), whilst NH,ZrF,(H,O) goes to Zr4Fl,03.ZrF4,H,0 is hydrolysed to ZrF3( OH),H,O and ZrF2( OH),,H,O ; when heatedthe hydroxy-fluorides are converted into polymeric oxyfluorides. 176Vanadium, Niobium, and Tantalum.-Zero-positive complexes ML,(M = V, Cr, W) of the disphosphine Me,P*CH,*CH,*PMe, can be preparedby reduction of the metal halides in tetrahydrofuran in the presence ofthe diphosphine with lithium aluminium hydride or sodium naphthenide.The complexes are unstable with respect to oxidation; the vanadiumcompound is paramagneti~.~'~ The stable phases in the vanadium pent-oxide-lithium oxide system have ratios of the two constituents of 3 : 1, 1 : 1,and 1 : 3.178 Five-co-ordinated vanadium is found in bisacetylacetonato-oxovanadium (IV) ; the vanadium atom is near the centre of gravity of a squarepyramid of oxygen atoms from the two acetylacetonate groupings and thevanadyl oxygen.179 The reactions between vanadium and niobium penta-fluorides and some nitrogen bases have been studied. Vanadium penta-fluoride yields NH,VF, ,pyVF,, and en3VF4 ; niobium pentafluoride gives(NH,),NbF, and en,.$TbF,. The structures of these compounds and thephysical significance of their stoicheiometries are unknown. 180 Electro-lytic reduction of a vanadium(v) salt in hydrofluoric acid gives VF2,4H,O; aseries of acid salts VF,,xHF,GH,O (x = 1 to 5 ) are also forrned.l8l Vana-dium trichloride and trioxide interact in a sealed tube to give the reddish-brown oxychloride, VOCl. 182 Tripositive vanadium can be stabilised intetrahedral co-ordination in a caesium tetrachloroaluminate lattice ; thetetrahalogenovanadate(rr1) ions are deep blue ;lS3 salts of these anions canbe prepared by interaction of tetraethylammonium halides with vana-dium(m) halides in acetonitrile followed by removal of the acetonitrile ofsolvation at Vanadium trihalides are solvolysed by liquid ammonia;the primary product from the trichloride is VCl,(NH,),4NH3 which breaksdown when heated to give V(NH)Cl and then to VN.Vanadium dichloridegives ammines on reaction with ammonia at room temperature but ammono-lysis occurs a t higher temperat~res.1~~ A structural study of niobiumdioxide shows that it is built up from NbO, octahedra sharing edges andcorners. In agreement with the low magnetic susceptibility the niobium1 7 5 J.L. Hoard, G;. L. Glen, and J. V. Silverton, 3. Amer. Chenz. SOC., 1961,83, 4293.1'6L. Kolditz and A. Feltz, 2. anorg. Chern., 1961, 310, 204, 217.1 7 7 J. Chatt and H. R. Watson, Nature, 1961, 189, 1003.178R. Kohlmuller and J. Martin, Bull. Xoc. chim. France, 1961, 748.lT9R. P. Dodge, D. H. Templeton, and A. Zalkin, J. Chem. Phys., 1961, 35, 55.ISOR. G. Cave11 and H. C. Clark, J . Inorg. Nuclear Chem., 1961, 17, 257.lslH.-J. Seifert and B. Gerstenberg, Angew. Chem., 1961, 73, 657.l82D. M. Gruen and R. Gut, Nature, 1961, 190, 713.la3D, E. Scaife, Vth Internat. Cod. Co-ord. Chem., London, 1959, The Chemical1 8 4 G. W. A. Fowles, P. G. Lanigan, and D. Nicholls, Chenz. and Ind., 1961, 1167;Society, London, 1960, p. 152.H. Remy and I.May, Naturwiss., 1961, 48, 524SHARP: THE TRANSITION ELEMENTS 125atoms are moved towards each other in pairs joined by a metal-metalbond.185 The system Cs,0-Nb,06 contains phases with the oxides in theratios 5 : 13, 2 : 15, 1 : 2, 2 : 3, and 1 : 1.18s Fluorination of NbCI,,PCI,with arsenic trifluoride gives [NbClJB, an ionic substance which meltst o the covalent form NbC1,F. This type of behaviour is well knownwith halides of the phosphorus group but does not appear to have beenpreviously recognised in the transition series. Arsenic trichloride reactswith NbCl,,PCI, to give N~C~,,PCI,,ASCI,.~~~ The system of niobium oxy-chlorides has received considerable attention and it has now been establishedthat NbOCI, (two forms), NbO,Cl, and Nb,O,CI are all stable phases.Theoxytrichloride can be reduced with hydrogen or niobium to the oxydichloridewhich reacts with pentachloride to give the oxytrichloride and niobium tetra-chloride. A similar tantalum oxychloride, TaOCl,, is formed by heatingsilica or tantalum pentoxide and tantalum pentachloride. 188 Niobiummetal will reduce niobium pentabromide to the t'etra- and tri-bromide.Both of these can be transported in a temperature gradient; the tribromidehas a wide range of homogeneity, the lower limit being Nb,Br8.ls9Chromium, Molybdenum, and Tungsten.-The reaction between lithiumnitride and metals or metal nitrides at high temperatures under an atmo-sphere of nitrogen gives double nitrides Li,MN, (M = Cry Mo, W). Thechromium compound is miscible with lithium oxide and probably has anantifluorite structure.lgO Solutions of chromous salts in the presence ofpolyamines liberate hydrogen from homogeneous solution by an autocataly-tic reaction which gives polyamine complexes of chromium(m) as the otherproduct.191 Very closely allied to this are the observations that chro-mium(@ complexes of salicylic acid, 5-sulphosalicylic acid, or ethylene-diaminetetra-acetic acid are some of the most powerful reducing agentsknown in aqueous solution.The anodic half-wave potential for theCr2 f-Cr3 +-ethylenediaminetetra-acetic acid complex at pH 12 is + 1.48 v.192Chromium sesquioxide reacts with chromium monocarbide to give thecubic monoxide but the action of hydrogen on a mixture of the sesquioxideand Cr3C, gives a new carbide, Cr2C.lg3 The reaction between dichromatesand anhydrous alcohols gives solutions containing [ROCrO,] - anions ; theultraviolet spectra of these solutions are in complete accord with the loss oftetrahedral symmetry in going from a chromate to an alkoxychromate(vI)grouping.lg4 A survey of the older literature has shown many compoundsthat may be heteropolychromates ; iodates react with chromium trioxide togive salts MCrIO, and the ammonium salt has been shown to contain atetrahedral chromate ion which shares one oxygen atom with a trigonallS5 B.-0.Marinder, Acta Chem. Scund., 1961, 15, 707.lssA. Reisman and J. Mineo, J . Phys. Chem., 1961, 85, 996.lS7L. Kolditz and G. Furcht, 2. anorg. Chem., 1961, 312, 11.lS8 H.Schafer, E. Sibbing, and R. Gerken, 2. anorg. Chem., 1961,307,163; K. HubrlseH. Schafer and K.-D. Dohmann, 2. anorg. Chem., 1961, 311, 134.IsoR. Juza and J. Hary, 2. anorg. Chem., 1961, 309, 276.lslK. D. Kopple, G. F. Svatos, and H. Taube, Nature, 1961, 189, 393.lS2R. L. Pecsok and W. P. Schaefer, J . Arne?. C'hem. SOC., 1961, 83, 62.IS3H. Lux and L. Eberle, Chem. Ber., 1961, 94, 1562.lg4U. KlBning and M. C. R. Symons, J., 1961, 3204.and I. Baunok, Chimia, 1961, 15, 365126 INORGANIC CHEMISTRYiodate ion. lg5 2,2’-Bipyridyl and o-phenanthroline complexes are generallyprepared by reaction between the ligand and a metal compound in a lowoxidation state, but it has now been found that direct reaction between theligands and hexa-aquochromium(m) ions yields diaminodihydroxy-complexeswith no formation of the triamino-derivatives.Two forms of these diaminecomplexes are known; what is probably the trans-form comes out of solutionwhilst the cis-form remains in.lS6 Chromyl azide has been prepared bydirect reaction between chromium trioxide and hydrazoic acid in an inerts01vent.l~~ The structure of chromium(I1) chloride shows octahedra ofchlorine atoms about each chromium atom; as is usual with chromium(n)compounds the octahedron is distorted to contain two long and four shortCr-CI bonds.198 Chromium(m) chloride and oxide react to give CrOCl;this oxychloride is decomposed by heat.lg9 Two new borides, MoB,and WB,,have been prepared by interaction of the elements a t 1100°.200 Infraredstudies of the complex molybdenum(m) thiocyanates indicate that these areisothiocyanates with nitrogen bonded to the metal; the water of crystalli-sation in these compounds is not bonded to the metal. From magneticstudies it is inferred that K,Mo( CN) ,,2H,O contains seven-co-ordinatemolybdenum.201 Mo~S, has been found to have a structure very similarto that of niobium dioxide; the co-ordination about the metal is octahedralbut pairs of molybdenum atoms are joined by a metal-metal bond.202The solvolysis of molybdenum halides has received much attention.Thepentachloride gives adducts with tertiary amines but aminolysis occurswith primary and secondary amines to give products of the typesMoCl,(NRR’), and MoCl,(NRR’), (R, R‘ = alkyl or H).,03 Solvolysisoccurs with methanol to give MoCl,( OMe), , MoCl,( OMe),,SMeOK, andMoOC1,,2MeOH which react with pyridinium chloride to give[pyH][MoCl,( OMe),] or [pyH][MoOCl,].Mo02C12 and W02C12 with alcoholsgive alkoxides Mo,(OR), but Mo02C1, gives a series of complexes withacid anhydrides, esters, ethers, ketones, aldehydes, and nitriles in whichthere has been no breaking of the Mo-C1 b0nd.20~ It is only just becomingapparent how extremely reactive molybdenum pentachloride is, and it hasbeen found t o be dissociated into MoCl, and chlorine even in carbon tetra-chloride solution.205 Hexagonal tungsten nitride has been identified asW2N. The co-ordination about the nitrogen atoms is octahedral but theco-ordination sphere about the tungsten consists of a pyramid of three nitro-195K.-A.Wilhelmi and P. Lofgren, Acta Chem. Scad., 1961, 15, 1413.196R. G. Inskeep and J. Bjerrum, Acta Chem. Scand., 1961, 15, 62.197H.-L. Krauss and F. Schwarzbach, Chem. Ber., 1961, 94, 1205.198 J. W. Tracy, N. W. Gregory, E. C. Lingafelter, J. D. Dunitz, H.-C. Mez, R. E.Rundle, C. Scheringer, H. L. Yakel, jun., and M. K. Wilkinson, Acta Cryst., 1961, 14,927; cf. H. R. Oswald, Helv. Chim. Acta, 1961, 44, 1049.199H. Schafer and F. Wartenpfuhl, 2. anorg. Chem., 1961, 308, 282.2 o o A . Chretien and J. Helgorsky, Compt. rend., 1961, 252, 742.201 J. Lewis, R. S. Nyholm, and P. W. Smith, J., 1961, 4590.202 F. Jellinek, hTature, 1961, 192, 1065.203D. A. Edwards and G. W. A. Fowles, J., 1961, 24.204 H. Funk, F.Schmeil, and H. Scholz, 2. anorg. Chem., 1961, 310,86; H. Funk, E.Ebert, and F. M o w , 2. Chem., 1961, 1,190; H.-L. Krauss and W. Huber, Chem. Bey.,1961,94, 2864; cf. D. C. Bradley, R. K. Multani, and W. Wardlaw, J., 1958, 4647.205 I. &I. Pearson and C. S. Garner, J . Phys. Chem., 1961, 65, 690S H A R P : THE T R A N S I T I O X ELEMENTS 127gen atoms together with one tungsten atom.206 On acidification of tungstatesolutions there is immediate polymerisation to the [HW,02,15- Themagnetic susceptibilities of the lower tungsten oxides, WO,, have beeninterpreted in terms of a general model in which (3 - x) oxygen atoms havebeen removedfrom the W0,lattice to leave 2(3 - x) electrons in the conductionbands of the host lattice.208Manganese, Technetium, and Rhenium.-Structural studies onMnI1[MnJ1( OH2)HY],,8H20 (H4Y = ethylenediaminetetra-acetic acid) haveshown that half of the manganese atoms are seven-co-ordinate witha co-ordin-ation arrangement similar to that found in the NbF72- Potassiumpermanganate has long been known to dissolve in sulphuric acid to give a greensolution and it has now been suggested that this contains the Mn03+ ion.210Fluorination of most manganese compounds at 550" in a stream of fluorinegas gives the blue tetrafluoride ; the new tripositive complex fluorides KMnF,and RbMnF, are obtained by reducing KMnF, and RbMnF, with hydro-gen.211 By contrast with the fluorides the higher manganese chlorides areextremely unstable.Manganese dioxide and hydrogen chloride react incarbon tetrachloride to give a dark green compound which can be extractedinto ether.It cannot be isolated in pure form but gives (Et4N)2MnCl,with tetraethylammonium chloride.212 Some of the major advances intechnetium chemistry have been described under the headings of carbonylsand complexes with aromatic systems. A study has been made of thecomplex technetium cyanides : technetium dioxide dissolves in aqueouspotassium cyanide to give a solution from which Tc,[Tc(OH),(CN),] can beisolated ; technetium-(Iv) or -(VII) species in cyanide solution are reduced bypotassium amalgam to give green K,TCI(CN)~ which appears to be verysimilar to the corresponding rhenium compound.213 The first technetiumfluoride, the golden-yellow hexafluoride, m.p.33", has been prepared bythe action of fluorine on metallic technetium.214 Rhenium chemistry hasbeen the subject of a r e v i e ~ . ~ l , Perrhenic acid reacts with tertiary phos-phines and acids, HX, in ethanol to give ReOL2C13, ReO(OEt)L,Br,, andReO(OEt)L,I,. ReOL2C12 is converted into ReO( OEt)C12L2 when boiledwith ethanol. 216 Two types of rhenium-containing perovskites have beendescribed. The series A1x(B110.,ReV10.,)03 results from the interaction ofthe appropriate metal oxides, whilst rhenium metal reacts with a mixtureof barium and alkali-metal carbonates to give Ba(M10.,ReV11,.,)0,.217206 V. I. Khitrova and Z . G. Pinsker, KristallograJiya, 1960, 5, 711 [679].207Y. Sasaki, Acta Chem. Scand., 1961, 15, 175.208 M. J. Sienko and B.Banerjee, J . Amer. Chem. SOC., 1961, 83, 4149.209 J. L. Hoard, B. Pedersen, S. Richards, and J. V. Silverton, J . Anaer. Chem. SOC.,210 I>. J. Royer, J . Inorg. iVuclear Chetn., 1961, 17, 159.211R. Hoppe, W. Dahne, and W. Klenim, Xatiirzuiss., 1961, 48, 429; R. Hoppe,213 ?T. S. Gill, Chem. and Ind., 1961, 989.213 W. Herr and K. Schwochau, Angew. Chena., 1961, '73, 492.214 H. Selig, C. L. Chernik, and J. G. Rlalm, J . Itzorg. Nuclear Chem., 1961, 19, 377.215 A. A. Woolf, Quart. Rev., 1961, 15, 371.216 C. J. L. Lock and G. Wilkinson, Chenh. and 1 ) ~ d . , 1962, 40; J. Chatt and G. A.Rowe, ibid., p. 92; cf. M. Freni and 1'. Valenti, J . Irtory. Nuclear Chem., 1961, 16, 240.217 A. W. Sleight and R. Ward, J . Amer. C'heni. SOC., 1961, 83, 1088; J.Longo andR. Ward, ibid., p. 2816.1961, 83, 3533.W. Liebe, and W. Dahne, 2. anorg. Chem., 1961, 307, 276128 INORGANIC CHEMISTRYRhenium has a high affinity for oxygen-containing ligands, and rhenium(1v)has been shown to form extremely stable complexes with organic hydroxy-acids.21s Rhenium trichloride reacts with N-dialkyldithiocarbamates to giveproducts ReCl,(NR2*CS,) which probably contain a bidentate dithiocar-bamate grouping.219Iron, Ruthenium, and Osmium.-Ultraviolet spectra and reactions withdimethyl sulphate to give the corresponding dimethyl-isocyanide complexessuggest that the product of the protonation of dicyanobis-o-phenanthroline-iron(=) and its 2,2'-bipyridyl analogue should be formulated as[phen2Fe(C=NH),]2 + ; the infrared spectra suggest that the protonationoccurs on cis-cyano-groups.220 The reaction between the amminepenta-cyanoferrate ion and azide or thiocyanate ions, which gives purple or bluesolutions, has long been used as an analytical method for detection of these.latter ions. The deeply coloured species have now been isolated as saltsand are the [Fe(CN),X]3- (X = N3, NCS) anions.221 The tetradentateligand As( CH,*CH,*CH,*ASM~,)~ forms complexes with iron(II), iron(rn),cobalt(m), nickel(II), and nickel(m) derivatives. The dipositive complexesare of the form M chel X2 and are six-co-ordinate; the tripositive complexesare again six-co-ordinate and are of the form [M chel X,]Y.222 Ethylene-dianiinetetra-acetic acid can act as a complexing agent to stabilise thepurple ferrate(vr) species produced by the action of hydrogen peroxide onferric hydroxide;223 in the complex RbFe(OH,)Y,H,O (H,Y =.ethylene-diaminetetra-acetic acid) the iron atom is seven-co-ordinate, having a co-ordination sphere in the form of a distorted pentagonal bi~yramid.~2~ Aseries of tetrahalogenoferrates(rr) has been prepared and it has been shownthat the FeX,2- anions are spin-free dy3dB3 complexes.225 There hasbeen oonsiderable interest in the interstitial compounds of ruthenium andthe other platinum metals. New borides and carbides MB,, M,B,, and MC(M = Ru and 0s) have been described,2Z6 and a full study of the platinum-metal arsenides has given the phases RuAs, RuAs2, OsAs2, Rh2As, RhAs,RhAs,, RhAs,, IrAs,, IrAs,, Pd3As, PdAs,, and PtAs,.227 Ruthenium metalreacts with fluorine to give a new, fairly involatile, hexafluoride.It is a darkbrown compound which decomposes to ruthenium pentafluoride and fluorinea t 200O.228 Anhydrous ruthenium tribromide has been prepared by inter-action of ruthenium metal and bromine; it is insoluble in water.229 Pre-21sB. Jezowska-Trzebiatowska and S. Wajda, Bul. Acud. polon. Xci., Ser. Sci.chim., 1961, 9, 57; B. Jezowska-Triebiatowska, S. Wajda, and W. Wojciechowski,&bid., p. 65.219R. Colton, R. Levitus, and G. Wilkinson, J., 1960, 5275.z20N. K. Hamer and L. E. Orgel, Nature, 1961, 190, 439.221B. Jaselskis, J . Amer. Chem. SOC., 1961, 83, 1082.222 G. A. Barclay and A. K. Barnard, J . , 1961, 4269.223G. L. Kochanny, jun., and A.Timnick, J . Amer. Chenz. SOC., 1961, 83, 2777.224 J. L. Hoard, M. Lind, and J. V. Silverton, J. Anier. Chenz. Xoc., 1961, 83, 2770.225N. S. Gill, J., 1961, 3512.226 C. P. Kempter and M. R. Nadler, J . Chem. PAys., 1960, 33, 1580; C. P. KempterZ27R. D. Heyding and L. D. Calvert, Canad. J. Chem., 1961, 39, 955.228 H. H. Claassen, H. Selig, J. G. Malm, C. L. Chernick, and B. Weinstock, J . Amer.229 S. A. Shchukarev, N. I. Kolbin, and A. N. Ryahov, Zhur. neorg. Khim., 1960,and R. J. Fries, ibid., 1961, 34, 1994.Chem. SOC., 1961, 83, 2390.5, 1900 [923]SHARP: THE TRANSITION ELEMENTS 129vious work on the species found in aqueous solutions of ruthenium(1rr)chloride has shown the existence of RuC12+ and of two isomeric forms ofRuCl,+; two forms of the neutral complex, RuCl,aq., have now been iso-lated.230 A solution of ruthenium( IV) in perchloric acid contains ruthenium-oxygen species with an average charge of 3-2.There is extensive formationof polymers but an Ru02+ ion has been identified.231 The green-colouredcompound that results from the action of iodide on osmium tetroxide inhydrochloric acid has been identified as either H[ OsI,(H,O)] or H2[ OsI,( OH)].Mixed halogeno-osmates(Iv), KOsCl,. are formed in the same reaction ;this anion, unlike Os162-, is fairly stable to hydrolysis.232Cobalt, Rhodium, and Iridium.-The American Chemical Society haspublished a monograph on the chemistry and metallurgy ofLigand-field theory predicts that for a series of octahedral transition-metalions arranged in the order of the field strength of the ligands there will bespin-free compounds at the low-field end and spin-paired compounds at thehigh-field end of the series.At some intermediate ligand field, spin-freeand spin-paired states should be in equilibrium. It appears that such anequilibrium occurs in di-( 2,6-pyridinedialdehyde hydrazone)cobalt(n) iodide,and the magnetic susceptibility can be interpreted in terms of an equilibriumbetween doublet and quartet ~ t a t e s . 2 ~ ~ Oxidation of pentacyanocobalt(rr)species with oxygen and ferricyanide gives the binuclear complexes[ (NC),CO~~~O,COI~~(CN)~]~- and [ (NC),Fe11CNCo1*1(CN)5]5 - but oxidation ofpentacyanocobalt(n) species with hydrogen peroxide, persulphate, or[ (NC),CO~~IO,CO~~~(CN)~]~- gives [ (NC),COIII(OH,)]~ - as the major product.The [(NC),CoI1I(OH2)]2- ion is polymeric in solution and in the solid andthere is no evidence for five-co-ordinate cobalt in any of these complexes. Asa contrast to these reactions, the pentacyanochromate(11) ion is oxidisedby both oxygen and hydrogen peroxide to give hexacyanochromium(m) spe-cies. 235 A crystal structure determination on [ (NH3),Co0,Co(NH,),][N03]5shows that the axis of the bridging peroxide group is perpendicular to theline joining the two cobalt atoms; the two cobalt and the two oxygen atomsare in the same ~ l a n e .2 ~ ~ Several new series of cobalt complexes have beenprepared. Bisoxalatoethylenediaminecobalt(rr1) salts and the correspond-ing malonato-complexes can be prepared by oxidation of cobalt(I1) acetate,potassium oxalate, or malonate, and ethylenediamine hydrochloride withlead dioxide ; the oxalatobisethylenediaminecobalt(rrr) ion can be synthe-sised similarly and all of these ions can be separated into their opticallyactive isomers.237 Each of the azido-complex ions [Co en,(N,),] +,[Co en,N,Cl]+, and [Co en2N3(0H,)l2+ exists as two forms which are230R.E. Connick and D. A. Fine, J. Amer. Chena. SOC., 1961, 83, 3414.231F. P. Gortsema and J. W. Cobble, J. Amer. Chem. SOC., 1961, 83, 4317.2s2 E. Fenn, R. S. Nyholm, P. G. Owston, and A. TUPCO, J. Inorg. Nuclear Chem.,233 R. S. Young [Ed.], “ Cobalt,” Rheinhold.Pub1. Co., Kew York, 1960.234R. C. Stoufer, D. H. Busch, and W.B. Hadley, J. Amer. Chem. SOC., 1961, 83,235A. Haim and W. K. Wilmarth, J . Amer. Chem. SOC., 1961, 83, 509.236 C. Brosset and N.-G. Vannerberg, Nature, 1961, 190, 714; of. A. A. VIEek, Trans.2s7 F. P. Dwyer, I. K. Reid, and F. L. Garvan, J . Amer. Chem. SOC., 1961, 83, 2285.1961, 17, 387.3732.FarmJay SOC., 1960, 56, 1137.130 INORGANIC CHEMISTRYpresumably cis- and trans-isomers. These complexes are important sincethey are widely used in the study of the kinetics of reactions of cornple~es.23~Cobalt(I1) chloride reacts with potassium selenocyanate in ethanol in thepresence of tetraphenylarsonium chloride to give (Ph,As),[Co(NCSe),]. Theinfrared and ultraviolet spectra of this complex and of complexes containingthe [Co(N3),I2- and [Co(NC0),l2- ions indicates nitrogen-cobalt bondingwith definite evidence for tetrahedral co-ordination about the metal in thelast two complex ions.239 In the series Copy,L, (L = SeCN, SCN, OCN)the selenocyanate and thiocyanate complexes have octahedral co-ordinationabout the metal with the ligands L acting as bridges.However, the cyanateis tetrahedral and this change in stereochemistry is believed to be associatedwith the small bridging capabilities of the cyanate ion occasioned by theabsence of d orbitals of appropriate energy on the oxygen at0m.2~~ Incontrast to these complexes which all contain cobalt-nitrogen bonds,Co(SCN),(Ph,P), is considered to be tetrahedral with the thiocyanate groupbonded to the cobalt through the sulphur atom.241 The phases in thesystems MC1-CoCl, have been identified as Li,CoCl,, M,CoCl, (M = Li, Na,K, Rb, Cs), MCoCl, (M = Li, K, Rb, Cs), M3CoCl, (M = Rb, Cs), Cs,Co2Clg, andCS,CO,C~,.~~~ Chlororhodates(II1) react with formic acid to give the greenrhodium(r) salt HRh(HCO,),,H,O ; air-stable pyridinium and ammoniumsalts have been isolated.243 The broad-line proton magnetic resonance spec-trum of the compound known as K3Rh(C,0,),,4,5H20 shows that it shouldbe formulated as K6[Rh(C,04)3][Rh(C,04),(HC204)( OH)],8H20 ; the corre-sponding monohydrate is K6[ Rh(C,O,), ][ Rh( C,O,),(HC,O,) (OH)],H,O. 244Rhodium metal burns in fluorine gas to give rhodium hexafluoride; this isthe &st known hexa-positive rhodium derivative; the solid is black and thecompound is red-brown in the gaseous state. ,45 The hexachlororhodate(1v)anion appears to be stabilised in a hexachloroplatinate(w) or hexachloro-palladate(1v) lattice ; it is blue-green in c o l o ~ r .~ ~ ~Nickel, Palladium, and Plathwlz.-Some reactions which lead to complexcyanides of zero- and uni-positive nickel have been investigated in detail.A mixture of nickel metal, mercuric cyanide, and potassium cyanide heatedto 500" in vacm gives K,Ni(CN), + K,Ni(CN),; Kai(CN), and KCN reactat 480" to give K,Ni(CN),, K3Ni(CN), is produced by heating togetherK,Ni(CN),, KCN, and nickel meta1.247 Nickel carbonyl reacts with dinitro-gen tetroxide in the gas phase to give Ni(NO,),; this is only the second238P. J. Staples and M. L. Tobe, J . , 1960, 4812239 A.TUPCO, C. Pecile, and M. Niccolini, Proc. Chem. SOC., 1961, 213; F. A. Cottonand M. Goodgame, J . Amer. Chem. SOC., 1961, 83, 1777.2 4 0 s . M. Nelson, Proc. Chem. SOC., 1961, 372.241 F. A. Cotton, D. M. L. Goodgame, M. Goodgame, and A. Sacco, J . Amer. Chem.SOC., 1961, 83, 4157.242H.-J. Seifert, 2. anorg. Chem., 1961, 307, 137; K. A. Bolschakov, P. I. Federov,and G. D. Agaschkina, Zhur. neorg. Khim., 1957, 2, 1115.243 I. I. Chernyaev, E. V. Shenderetskaya, and A. A. Karyagina, Zhur. neorg. Khirn.,1960, 5, 1164 [559].244A. L. Porte, H. S. Gutowsky, and G. M. Harris, J . Chem. Phys., 1961, 34, 66.245C. L. Chernick, H. H. Claassen, and B. Weinstock, J . Amer. Chem. SOC., 1961,346R. Kiriyama, K. Ogawa, and M. Azumi, J . Chern. SOC. Japan, 1961, 82, 328.247 S.von Winbush, E. Grismold, and J. Kleinberg, J . Amer. Chem. SOC., 1961, 83,83, 3165.3197SHARP: THE TRANSITION ELEMENTS 131known anhydrous transition-metal nitrite. 248 The reactions of nickel(@,palladium(rr), and platinum(n) complexes of dimethylglyoxime (H,DMG)and 2-pyridinaldoxime (HPAX) with acetyl chloride have been re-investi-gated. All of the dimethylglyoxime complexes give MI1( H2DMG)C1, deriva-tives plus the free diacylated ligand. The 2-pyridinaldoxime complexesare completely destroyed in the case of nickel; the palladium complex givesPd( CH,-CO-PAX)Cl, which can be readily hydrolysed to [ Pd( PAX)Cl], ;the platinum complex is diacylated to [ Pt(CH,=CO*PAX),]C1,.2*9 Bisethyl-enediamine-nickel(=) and -copper(=) salts react with acetone to give com-plexes (e.g., 21) which are formulated to contain C6The colour changes of the Lifschitz salts, Ni(m,eso-explained in terms of changes in the ligand field onthe axial positions of a tetragonal complex.It ispossible that these changes in field strength areCH2 (21)brought about by an anion which is not in the firstco-ordination sphere of the nickel atom.251 Potas-sium fluorosulphinate, KSO,F, is a suitable fluorinating agent for convertingcomplexes such as Ni(PC1,)4 into Ni(PF,),. The latter reacts with ammoniato give Ni[P(NH,),], which is converted into the polymer [Ni(PN),], byThe stereochemical configuration about the nickel atom in thecomplexes L,NiX, (L = Bun,PhP, BunPh,Py Ary1,P; X = C1, Br, I, SCN,or NO,) appears to be related to the number of phenyl groups on the sub-stituted phosphine.Triarylphosphine complexes are pseudo-tetrahedralwhen X = halogen but are presumed to be planar when X is a thiocyanategroup ; the butyldiphenylphosphine complexes are paramagnetic and pseudo-tetrahedral in the solid but dissolve in benzene to give a mixture of thediamagnetic and the paramagnetic form ; the dibutylphenylphosphine com-plexes are diamagnetic in the solid and have tram-planar str~ctures.~~3 Thecomplex [Me*As(CH,*CH,*CH,*AsMe,),]NiBr, contains five-co-ordinatednickel. The three arsenic atoms are in a plane with one bromine atomnormal to this plane.and above the nickel. The remaining bromine atomis depressed 20” below a position which would complete a square pyramidand it is suggested that if it were in the more normal square position therewould be considerable steric interaction with the terminal methyl groups onthe arsenic atoms.The palladium and the platinum analogue are ionic andhave the structures [M(arsine)Br]Br, and it is generally found that for thenickel group the occurrence of co-ordination number five is Ni >> Pd > Pt(for an example of five-co-ordinated platinum see ref. 261). Each ofthese metals gives complexes [M(arsine),][ClO,], in which the metal has248 C. C. Addison, B. F. G. Johnson, N. Logan, and A. Wojcicki, Proc. Chem. SOC.,1961, 306.249 R. A. Krause, D. C. Jicha, and D. H. Busch, J . Amer. Chem. SOC., 1961, 83, 528.250N. F. Curtis and D. A. House, Chenz.and Ind., 1961, 1708.251 S. C. Nyburg, J. S. Wood, and W. C. E. Higginson, Proc. Chem. SOC., 1961, 297.262F. Seel, K. Ballreich, and R. Schmutzler, Chem. Ber., 1961, 94, 1173.253C. R. C. Coussmaker, M. Hely Hutchinson, J. R. Mellor, L. E. Sutton, andL. M. Venanzi, J . , 1961, 2705; M. C. Browning, R. F. B. Davies, D. J. Morgan, L. E.Sutton, and L. M. Venanzi, J., 1961, 4816.CHMeC CMetunits joined in to act as tetradentate ligand~.~~Oly2-diphenylethylenediamine),( RCO,),, have been/ \ 2H,C”\ / “ C H 2 M IH2C--. N N ’ ‘ ,‘HZMelC, ,CMeI I132 INORGANIC CHEMISTRYoctahedral co-ordination from arsenic atoms. 254 Bisacetylacetonatonickel(11)is trimeric, each nickel atom having a co-ordination number of six;255 thistype of association has been used to explain the magnetic and spectralproperties of nickel(n) complexes of other diketones, salicylaldimines, andsalicylaldehyde.Green diaquodisalicylaldehydatonickel (n) is a monomerwith a normal trans-octahedral configuration. 257 A suspension of palla-dium(=) fluoride in selenium tetrafluoride is converted into CsPdF, byaddition of czsium fluoride; a solution of palladium(rr1) fluoride in thissolvent is readily oxidised to palladium(1v) by the action of bromine tri-Lithium metal reacts with platinum in vacuo or under argonto give a new phase TiPt, which is an extremely reactive catalyst.259 Struc-tural determinations on two compounds of what appears to be tripositiveplatinum have confirmed the view that compounds of this oxidation stateare generally built up from equiatomic mixtures of platinum-(@ and -(Iv).Pt enBr, contains Pt enBr, and Pt enBr, groups; the two series of Pt enBr,groups are linked by the other bromine atoms and there is considerablecharge transfer along the chain.Wolffrani's red salt should be formulated as[ PtIV( EtNH,),Cl,][ PtI1( EtNH2)4]C14,4H20.260 The tetradentate ligand (22)gives compounds of the type [Pt(arsine)X]Y (X = C1, Br, I, SCN; Y = C1,Br, I, SCN, ClO,, BPh,) with platinum@). These complexes contain five-co-ordinate platinum both in the solid and in solution, and a structuralstudy of the [Pt(arsine)I]+ cation shows that the co-ordination is in the.,PhASform of a trigonal bipyramid. The tridentate arsine (23) gives four-co-ordinated complexes of the type [ Pt(arsine)X]Y with platinum(I1)derivatives.261Copper, Silver, and Gold.-New methods have been described for thepreparation of some copper(1) salts in non-aqueous solvents. Cuprousoxide reacts with ammonium salts in liquid ammonia to give the [Cu(NH,),] +cation; the iodate is insoluble and can be obtained by metathetical exchange254 G. A. Mair, H. XI. Powell, and D. E. Hem, Proc. Chem. SOC., 1960, 415; G. A.Barclay, R. S. Nyholm, and R. V. Parrish, J., 1961, 4433.255G. J. Bullen, R. Mason, and P. J. Pauling, Nature, 1961, 189, 291.z66 F. A. Cotton and J. P. Fackler, jun., J . Amer. Chem. SOC., 1961, 83, 2818; J. P.Fackler, jun., and F. A. Cotton, ibid., p. 3775; H. C. Clark and R. J. O'Brien, Canad.J .Chem., 1961, 39, 1030; J. R. Miller and A. G. Sharpe, J., 1961, 2594.z57 J. M. Stewart, E. C. Lingafelter, and J. D. Breazeale, Acta Cryst., 1961, 14, 888.e5'3N. Bartlett and J. W. Quail, J., 1961, 3728.259 C. P. Nash, F. M. Boyden, and L. D. Whittig, J . Amer. Chem. SOC., 1960, 82,260 T. D. Ryan and R. E. Rundle, J . Amer. Chem. SOC., 1961,83,2814; B. M. Craven261 G. A. Mair, H. M. Powell, and L. M. Venanzi, Proc. Chem. SOC., 1961, 170; J, A.6203.and D. Hall, Acta Cry&., 1961, 14, 475.Brewster, C. A. Savage, and L. M. Venanzi, J., 1961, 3699SHARP: THE TRANSITION ELEMENTS 133wit8h lithium iodate. Cuprous ammines react with carbon monoxide togive unstable carbonyls CuX,CO,xNH, ;262 solutions of copper(n) salts inacetonitrile are reduced to copper@) by the action of metallicDi(pyridine-2-aldoximato)copper(11) is a complex in which hydrogen-bondformation confers extra stability on the actual complex in the same manneras in bisdimethylgl~oximatonickel(a).However, the hydrogen is still acidicand can be replaced by a silver ion to give a heterobinuclear chelate (24)which can be isolated as the p e r ~ h l o r a t e . ~ ~ ~ Magnetic and spectral studiessuggest that the triphenylphosphine oxide complexes CuL,X, are pseudo-tetrahedral but that the CuL42+ cation is square planar;265 however, themost definite information about stereochemistry can come only from X-raystructural determinations and full structures have shown unusual co-ordination arrangements in several copper salts. Diazoaminobenzene-copper(1) (PWN*NPh)Cu, is dimeric with pairs of diazoaminobenzeneM eC-C’C-MeMe-C\CMe-Cmolecules linked through copper atoms. The co-ordination about thecopper atoms is almost linear and although the copper-copper distance isonly 2.45 8 (cf. copper metal 2.55 8, copper acetate dihydrate 2.65 A)metal-metal bonding is considered not to be present.266 A complex acetyl-acetonato-o-hydroxyanilatocopper(n) complex which was previously for-mulated with three-co-ordinate copper has now been shown to have structure(25). The molecule is pseudo-dimeric with two types of copper atom:copper atom 1 is in square planar co-ordination whilst copper atom 2 isfurther bonded to an oxygen of another dimer and is five-co-ordinated.The Cu-Cu distance is 3.00 A and metal-metal bonding is not invoked;however, antiferromagnetic exchange interactions occur through the oxygenbridges and cause anomolous magnetic susceptibilities. 267 The complexesCu chel,(ClO,), (chel = o-phenanthroline or 2,Z’-bipyridyl) react with univa-lent anions to give five-co-ordinated species [Cuchel,X]+ (X = C1, Br, I,SCN, NO,, HCO,, CH,*CO,, PhCO,). The [Cudipy,I]+ cation has anapproximately trigonal bipyramidal configuration about the metal with theiodide in the equatorial plane; perchlorates [Cuchel,X][ClO,] are 1 : 1electrolytes in nitromethane whilst diperchlorates, Cu chel,(C10,),, are weak262R. Nast and C. Schultze, 2. unorg. Chem., 1960, 307, 15.26sB. J. Hathaway, D. G. Holah, and J. D. Postlethwaite, J., 1961, 3215.2e4C. H. Liu and C. F. Liu, J . Amer. Chem. SOC., 1961, 83, 4167.265D. M. L. Goodgame and F. A. Cotton, J., 1961, 2298.2seI. D. Brown and J. D. Dunitz, Actu Cryst., 1961, 14, 480.267 G. A. Barclay, C. M. Harris, B. F. Hoskins, and E. Kokot, Proc. Chem. SOC.,1961, 264; cf. M. Kishita, Y. Muto, and M. Kubo, Austral. J . Chem., 1957, 10, 386;1958, 11, 309134 INORGANIC CHEMISTRYelectrolytes with co-ordinated perchlorate groups. Many other perchlorato-complexes of this type have been recognised and salts of very strong acids(e.g., hexafluorophosphoric acid) can be prepared in which the perchlorategroup remains co-ordinatively bound whilst the other anion is present asa free ion.268 Royal-blue copper(@ formate is a dimeric molecule witheach copper atom bonded to four oxygen atoms in a plane and being furtherbonded to a fifth oxygen of a neighbouring molecule; there is no metal-metalbond.26s Five-co-ordinated copper is also found in Cr(NH3)6CUC15 in whichthe co-ordination sphere is that of a trigonal bipyramid with all of the Cu-Cldistances equal. 270 KCuF, has a pseudo-perovskite structure with threedifferent Cu-F distances (2.25, 1-96, 1.89 A), and it is clear that there mustbe very complex electronic interactions in the ions to give distortions ofthis type.271 The interactions between the alkali metals and the metalsof this group have been fully studied. No compound is formed with copper,and with silver a new phase, NaAg,, has been identified. Gold gives awhole series of new phases-Li : Au, 15 : 4 ; 3 : 1 ; 4 : 5 N a : Au, 2 : 1 ; 1 : 1 ;1 : 1 .272 Silver fluoroborate and hexafluorophosphate are readily preparedby reaction between silver@) fluoride and the non-metal fluoride in liquidsulphur dioxide.273 A whole series of silver(n) carboxylates have beendescribed as resulting from the oxidation of silver(1) species with persulphatein the presence of the appropriateZinc, Cadmium, and Mercury.-An X-ray study of zinc oxide which hasbeen doped by heating it in zinc vapour shows that many extra zinc atomsare taken up into the octahedral holes of the lattice. Most of these extraatoms are electrically ne~tra1.2~5 Previously there has been only oneknown example of five-co-ordinate zinc but it has now been shown thatboth (acac),Zn,H,O and NaZn(OH), have the zinc atoms surrounded bya distorted trigonal bipyramid of oxygen atoms. 276 Infrared spectralstudies on the complexes M en2C1, (M = Zn, Cd, Hg) suggest that in thesecompounds the diamine is acting as a bridge between two metal atoms.277(N2H5),Zn(S0,), appears to be representative of a whole series of salts ofthe hydrazinium cation. It is found that one nitrogen of each of thecations is co-ordinated to the metal which is six-co-ordinated with bondingfrom bidentate sulphato-groups. The proton is presumably attached to theun-co-ordinated nitrogen atom.278 BaZnO, reacts with hydrogen sulphide268 C. M. Harris, T. N. Lockyer, H. Waterman, G. A. Barclay, and C. H. L. Kennard,Nature, 1961, 192, 424; C. M. Harris and E. D. McKenzie, J . Inorg. Nuclear Chem.;1961, 19, 373.269 G. A. Barclay and C. H . L. Kennard, J . , 1961, 3289; cf. R. L. Martin and H.Waterman, J . , 1959, 1359.270M. Mori, Y . Saito, and T. Watanabe, Bull. Chem. SOC. Japan, 1961, 34, 295.271A. Okazaki and Y. Suernen, J . Phys. SOC. Japan, 1961, 16, 176.272G. Kienast, J. Verma, and W. Klemm, 2. anorg. Chem., 1961, 310, 143.273D. R. Russell and D. W. A. Sharp, J., 1961, 4689.274 E. Bogdan, M. Motas, and D. Giurgiu, Studii si Cercetari Sti. Chim. (Pi.!. Iasi),275G. P. Mohanty and L. V. Azhroff, J . Chem. Phys., 1961, 35, 1268.276E. L. Lippert and M. R. Truter, J., 1960, 4996; H. G. Schnering, Natzc~w~ss.,a7?G. Newman and D. B. Powell, J., 1961, 477.278C. K. Prout and H. M. Powell, J., 1961, 4177.1 : 2 - K : A ~ , 2 : 1 ; 1 : l ; 1 ~ 2 ; 1:4--Rb:Au,1:1; 1 ~ 2 : 1:4--Cs:Au,1960, 10, 15.1961, 48, 665; cf. D. E. C. Corbridge and E. G. Cox, J., 1956, 594S H A R P : THE TRANSITION ELEMENTS 135at 800" to give Ba,ZnS,; this complex has ZnS,-tetrahedra linked into chainsand the chains are held together by barium ions.279 It now seems extremelyprobable that solutions of cadmium metal in cadmium(@ halides containstable cadmium(1) species. The cations are polymeric, and a salt Cd,(AlCl,),has been isolated from such a solution.280 The infrared spectra of aqueoussolutions of cadmium cyanide complexes do not agree with polarographicmeasurements in showing the presence of a [Cd(CN),]2- ion; low concentra-tions of cyanide ion react with mercuric species to give polymeric ionscontaining more than one metal atom per cyanide grouping.281 Fromstudies of Raman spectra it is concluded that bis( trifluoromethy1thio)-mercury reacts with mercuric salts in solution to give CF,*S*HgX derivatives.Tetraethylammonium or alkali-metal halides give [ Hg( SCF,),X] - species. 282D. W. A. S.D. W. A. SHARP.A. G. SHARPE.27Q H. G. Schnering and R. Hoppe, 2. anorg. Chern., 1961, 312, 99.280 L. E. Topol and A. L. Landis, J . Amer. Chem. SOC., 1960,82, 6291 ; J. D. Corbett,281 R. A. Penneman and L. H. Jones, J. Inorg. Nuclear Chem., 1961, 20, 19.z8aA. J. Downs, E. A. V. Ebsworth, and H. J. Emeleus, J., 1961, 3187.W. J. Burkhard, and L. F. Druding, ibid., 1961, 83, 76