INORGANIC CHEMISTRY1. INTRODUCTIONTHIS year’s Report follows closely the pattern of those of recent years,elements being classified on the basis of the long form of the Periodic Table.General coverage of work published in 1959, rather than a series of reviews,has been attempted; the first volumes of two series devoted to reviews ofrecent work augment considerably the recent review literature of inorganicchemist rj7.l’The choice of a unified scale for atomic weights was discussed at the 1959meeting of the I.U.P.A.C.,3 and, provided the International Union of Pureand -4pplied Physics agrees, it seems certain that the exact number 12 forthe atomic weight of carbon-12 will become the primary standard in 1961.The 1957 Report of the I.U.P.A.C. Commission on Inorganic Nomenclaturehas now appeared.* of Palmer’s“ Valency ” and the collected papers presented at a Symposium on HydrogenBonding.6 Contributed papers to symposia on “ Mechanisms of InorganicReactions ” and “ The Teaching of Inorganic Chemistry ” have also beenpublished.’ The English translation of the Zhurnal neorganicheskoi Khimiiis now appearing.8Reviews have been published on inorganic polymer^,^ clathrate com-pounds,1° stereochemical effects of unshared pairs of electrons,ll quantitativestudies of hydrolytic equilibria,12 perfluoroalkyl derivatives of metals andnon-metals,13 lattice energies of inorganic mechanisms ofredox reactions,15 the Szilard-Chalmers effect in solids,16 graphitic com-pound~,~’ and mixed metal oxides.l8 Many other reviews are mentionedunder individual elements or in the general account of co-ordination com-pounds at the beginning of Section 3.New books include a revised edition“ Advances in Inorganic Chemistry and Radiocheniistry,” ed. H.J. EmelCus2 “ Progress in Inorganic Chemistry,” ed. F. A. Cotton, Interscience Publishers Inc.,and A. G. Sharpe, Academic Press Inc., New York, Vol. I, 1959.New York, Vol. I, 1959.See e.g., Proc. Chem. SOC., 1959, 330.W. G. Palmer, “ T‘alency,’’ C.U.P., 2nd edn., 1959.4 “ Nomenclature of Inorganic Chemistry,” Butterworths, London, 1959.6 “ Hydrogen Bonding,” ed. D. Hadii, Pergamon Press, London, 1959.7 J. Phys. Chem., 1959, 63, 321; J . Chem. Edztc., 1959, 36, 441, 502.8 Russzan Journal of Inorganic Chemistry, The Chemical Society, Landon ; the€I.J. EmelCus, Proc. Chem. SOC., 1959, 202; V. V. Korshak and 1C. K. Mozgova,translated journal a t present begins a t Vol. 4 of the original.TTspekAi Khim., 1959, 28, 783.10 L. Mandelcorn, Chem. Rev., 1959, 59, 827.11 A. W. Searcy, J. Chem. P l y . , 1959, 31, 1 .L. G. SillCn, Quart. Rev., 1959, 13, 146.13 J. J . Lagowski, Quart. Rev., 1959, 13, 233.T. C. Waddington, Ref. 1 , p. 158.15 H. Taube, Ref. 1, p. 1.G. Harbottle and N. Sutin, Ref. I , p. 268.17 W. Rudorff, Ref. 1, p. 224; G. R. Hennig, Ref. 3, p. 125-I* R. \Yard, Ref. 2, p. 465112 INORGANIC CHEMISTRY.Many papers continue to be published on inorganic chemistry in non-aqueous solvent systems; among solvents which have been investigatedduring the past year are acetyl chloride,lg benzoyl brornide,,O molten acet-amide,21 phosphorus oxychloride,22 selenium oxychloride,23 and moltenarsenic and antimony tribromide~.~~ Much of this work is summarised in arecent review.25 The properties of solutions in two well-investigated sol-vents, sulphuric acid 26 and sulphur dioxide,27 have also been criticallyreviewed; it now seems certain that simple self-ionisation according to theequationmust be eliminated as the basis for acid-base type interaction in the lattersolvent.As in the last year’s Report, the chemistry of organic derivatives ofnon-metals and metalloids is not covered systematically; the increasinguse of vacuum technique for the manipulation of volatile alkyl and sub-stituted-alkyl derivatives has led, however, to a blurring of the traditionalboundary between inorganic and organic chemistry in this field, and becauseof the very rapid progress made during the past year accounts of somework on these compounds have been included.2s0, = so,+ + so2-2.TYPICAL ELEMENTSHydrogen.-A review of the catalytic activation of hydrogen by metalions and complexes in solution has been published, and the RhCIe3- ion hasbeen added to the list of cata1ysts.lInterest in very strong hydrogen bonds has continued. A full analysisof the structure of palladium dimethylglyoxime shows that the O-H 0distance is 2.59 A (instead of 2.40 A as reported earlier); on the basis ofthe empirical relations between the 0-H 0 distance and the 0-Hstretching frequency which have been reported, this should correspond to~(0-H) -2450 cm.-l, but the molecule shows no important absorption in thisregion., (It is very surprising to find that in the isomorphous platinumderivative, O-H - 0 is reported to be 3.03 A and, incidentally, themiddle C-C bond of the ligand to be 0.lOA longer than in the palladiumcompound.) A similar state of affairs persists for other compounds1s R.C. Paul, D. Singh, and S. S. Sandu, J., 1959, 316, 319; K. Goyal, R. C. Paul,and S. S. Sandu, J., 1959, 322; B. S. Manhas, R. C. Paul, and S. S. Sandu, J., 1959,325; J . Singh, R. C. Paul, and S. S. Sandu, J., 1959, 845.2O V. Gutmann and K. Utvary, Monatsh., 1959, 90, 751.21 G. Jander and G. Winkler, J. Inorg. Nuclear Chem., 1959, 9, 24, 32, 39.22 V.Gutmann and M. Baaz, Monatsh., 1959, 90, 239, 256, 271, 426, 729, 744; 2.anorg. Chem., 1959, 298, 121.Z3 J. Klikorka and I. Pavlik, Chem. Listy, 1958, 52, 2222.a4 G. Jander and K. Giinther, 2. anorg. Chem., 1958, 297, 81; 1959, 298, 241;G. Jander and I<.-€€. Swart, ibid., 1959, 299, 252.25 V. Gutmann and M. Baaz. Angew. Chem., 1959, 71, 57.26 R. J. Gillespie and E. A. Robinson, Ref. 1, p. 386.87 T. H. Norris, J. Phys. Chem., 1959, 63, 383; J. L. Huston, ibid., p. 389.J . Halpern, J. Phys. Chem., 1959, 63, 398; J. F. Harrod and J. Halpern, Canad.D. E. Williams, G. Wohlauer, and R. E. Rundle, J. Amer. Chem. SOL, 1959,81, 755.J . Chem., 1959, 11, 1933.a E. Frasson, C. Panattoni, and R. Zannetti, Acta Cryst., 1959, 12, 1027containing short hydrogen bonds (e.g., potassium phenylacetate), and thevalidity of these relationships now appears d ~ u b t f u l .~ A preliminaryaccount of the structure of sodium hydrogen diacetate gives 0-H - - 0as 2-42 A in this compound; the infrared absorption spectrum does notappear to have been investigated. Mention of many other structures whichcontain hydrogen bonds is made elsewhere in this report.Group 1.-The properties of solutions of aIkali (and alkaline-earth) metalsin liquid ammonia and amines have been reviewed.6 Lithium borohydridehas been shown to form compounds with one, two, three, and four moleculesof ammonia.' Ammoniates of potassium, rubidium, and czsium amideshave been described, and a survey of the crystal structures of the alkali-metal amides has been given.*Pure lithium selenide, obtained by interaction of the elements in a sealedtube at 300°, is cream in colour, but turns red and liberates hydrogen selenideon exposure to air (hence previous reports that the cornpound is red).9 Astudy of the system NaF-HF-H,O a t 0" and -15' reveals the existenceof the following compounds : NaHF,; NaF,2HF; NaF,3HF; NaF,4HF.laThin sheets of czesium chloride evaporated on to an amorphous film carrierhave the NaCl structure; the Cs-Cl distance is 3.474& compared with3-566 A in ordinary body-centred cubic czesium chloride.llGroup 11.-Pure magnesium iodide may be obtained by the action ofmagnesium powder on molten mercuric iodide.12 In the system Mg(OH),-H,O,-MgO,, Mg(OH), and MgO, are the only solid phases; the lattercompound, like zinc and cadmium peroxides, has the pyrites structure withan 0-0 distance in the peroxide ion of 140A.Strontium peroxide octa-hydrate contains chains of composition -0,2--(Hz0),-022--(H20)8- inwhich strong hydrogen bonds hold the units together. The structure of thecompound BaO,,H,O, consists of Ba2+ ions and infinite helical chains ofperoxide groups, held together by hydrogen bonds.13A neutron-diffraction study of gypsum, CaS04,2H,0, shows that thesulphate ion contains two types of S-0 bond; two S-0 distances are1.479 5 0-010 and two 1-497 0.014 A, the latter being those of the S-0bonds which are hydrogen bonded to water molecules. There is, however,no significant departure from the tetrahedral angle for the sulphur ~a1encies.l~Confirmation that calcium carbide contains an acetylide ion has a t last beenprovided by another neutron-diffraction investigation : the C-C distanceis 1-20 A, much less than those in Lac, (1.28 A) and UC, (1.34 A), both ofwhich are metallic conductors (calcium carbide is an insulator).It is* N. Albert and R. M. Badger, J . Chem. Phys,, 1958, 29, 1193.J. C. Speakman, Proc. Chem. Soc., 1959, 316.M. C. R. Symons, Quart. Rev., 1959, 13, 99; W. 1,. Jolly, " Progress in InorganicE. A. Sullivan and S. Johnson, J . Phys. Chern., 1959, 63, 233.R. Juza and A. Mehne, 2. anorg. Chem., 1959, 299, 33, 41.W. D. Johnston and R. R. Heikes, J . Amer. Chem. SOC., 1958, 80, 5904.Chemistry," 1959, 1, 235.lo J.S. Morrison and A. W. Jache, J . Amer. Chem. SOC., 1959, 81, 1821.l1 K. Meyerhoff and J. Ungelenk, Acta Cryst., 1959, 12, 32.l2 J. O'M. Bockris and E. H. Crook, Chem. and Ind., 1959, 1163.l3 N.-G. Vannerberg, Arkiv Kemi, 1959, 14, 17, 99, 115, 125, 147; C. W. W. Hoff-l4 M. Atoji and R. E. Rundle, J . Chem. Phys., 1958, 29, 1306.mann, R. C. Ropp, and R. W. Mooney, J . Amer. Chem. Soc., 1959, 81, 3830114 I NOHG ANT(' CHEMISTRY.suggested that in the lanthanum and uranium compounds one or moreelectrons from the formally dipositive cation is in an antibonding orbital ofthe C22- ion which may overlap with a conduction band in the solid state.15Group 111.-Boron.' The enrichment of boron in boron-10 by means ofthe reactionAnisole,llBF,~li,~ + 1°BF3(,, a Ani~ole,~~BF,~~~,~ + 11BF3c,,for which the enrichment factor (l0B/l1B) (liq)/(l0B/l1B) (g) is 1.029 at 25",is a useful laboratory method; l6 an alternative process makes use of thet-butyl sulphide complex of boron triflu0ride.l' In a new method for thepreparation of elemental boron, a melt of potassium fluoroborate, potassiumchloride, and potassium fluoride is electrolysed a t 800", a Monel-metalcathode and a graphite anode1* being used.A new (rhombohedral) formof boron has been obtained by pyrolysis of boron tri-iodide vapour on tanta-lum, tungsten, or boron nitride a t 800-1000". The structure consists ofnearly regular icosahedra in a slightly deformed cubic close packing; halfthe boron atoms in an icosahedron are bound by conventional single bonds toatoms of other icosahedra, and each of the remaining atoms participates ina three-centre bond with two atoms from two different neighbouring icosa-hedra.lg Bonds within the icosahedron range from 1.73 to 1.79 A, conven-tional bonds to other icosahedra are 1.71 A, and three-centre bonds are2-03 A.Two reviews20921 of the structures of the boron hydrides give accountsof attempts to place them on a systematic basis; the discovery of newhydrides and of ions derived from them will be useful in testing structuraltheories.Diborane is formed from silane and boron trichloride in the presence ofmethyl radicals generated by the photochemical decomposition of azo-methane.22 It does not react with boron trichloride in the absence ofethers; in their presence, reactions according to the schemesB2H6 -t BCI3 + 3RzO 3RZ0,BHzCIB,H, + 4BC13 4- 6R20 6R20,BHC12take place.The formation of these products accounts for the low yield ofdiborane when alkali-metal borohydrides are treated with excess of borontrichloride in ethereal so1utions.a The interaction of diborane and silyl ortrimethylsilyl cyanide results in the formation of an adduct H,SiCN,EH, orMe,SiCN,BH, ; when this is heated the corresponding silyl hydride iseliminated and a solid polymer (BH,CN),, which is only slowly hydrolysedl5 M. Atoji and R. C. Medrud, J. Chem. Phys., 1959, 31, 333.l6 A. A. Palko, Ind. Eng. Chem., 1959, 51, 121.l7 A. A. Palko, J. Chem. Phys., 1959, 30, 1187.l8 G. T. Miller, J.Electrochem. Soc., 1959, 106, 815.19 B. F. Decker and J . S. Kasper, Acta Cryst., 1959, 12, 503.2o VC'. N. I,ipscomb, " Advances in Inorganic Chemistry and Radiochemistry," 1959,21 R. W. Parry and L. J . Edwards, J. Amev. Chem. Soc., 1959, 81, 3554.2% R. Schaeffer and L. Ross, J. Amer. Chrm. SOC., 1959, 81, 3486.23 H. C. Brown and P. A. Tierney, J. Inorg. Nuclear Chem., 1959, 9, 51.1, 118SH.IHPE TYPICAL f3IXMENTS. 115by hot water, is formed.= The di-n-butyl analogue of this polymer is aviscous liquid obtained from the compounds Bun2BC1 and Me,SiCN orAgCN; this substance, on treatment with sodium in liquid ammonia, givesthe hitherto unknown monomeric compound B U ~ ~ B O N H ~ . ~ ~ The trimer(Me2N*BH2), has been obtained by heating the dimeric compound withpentaborane.26 Diborane reacts with thiophan and diethyl sulphide toyield the compounds (CH,),S,BH, and Et,S,BH,; borane forms much morestable adducts than boron trifluoride with these thio-ethers, whereas thereverse is true for ordinary ethers.Moreover, adducts like Et,S,BH, aremuch more stable than their oxygen analogue^.^'Trimethylboron can be prepared by the action of the compound Me3Al.&13on boric oxide or borax at 100-170" or on butyl borate at room temper-ature.2s Alkylated boranes may be obtained by the interaction of sodiumborohydride, hydrogen chloride, and boron trialkyls at 150-175" ; the useof lithium borohydride or lithium aluminium hydride enables lower temper-atures to be employed.29 Alkylboranes are also formed when triethylamine-borane reacts with olefins (e.g., isobutene, hex-1-ene) a t 200" in the absenceof a ~olvent.~OAn X-ray diffraction study of the compound (NH3)2BHzCl shows thatthis substance is really [(NH3)2BH2]+C1-; since it results from the interactionof ammonium chloride and the " diammoniate of diborane," further evidencefor the formulation of the latter compound as [(NH,),BHI,J+BH,- is pro-vided.,l The velocity of hydrogen production in the reaction betweensodium borohydride and water shows that one hydrogen atom of the BH,-ion reacts faster than the others; the presence of the intermediate ionBH3*OH- has been proved by the isolation of a sodium salt and the studyof its infrared spectrum.32Ammonia-triborane, H,N*B,H,, may be obtained by the action ofammonium chloride on the compound NaB,H8 in the presence of etherat 25":An alternative method utilises the reactionsNaB3H, + NH&I + H, + H,N*B,H, + NaC2 5 OEtgO-78"B,HlO + R2O 4 #32H, + R20B,H,R,OB,H, + NH, __t H,N.B,H, + R,Obest yields being obtained when R20 = tetrahydrofuran.% The compoundis dimorphic, a disordered tetragonal form being stable at 25", and an24 E.C. Even, W. 0. Freitag, J. N. Keith, W. A. Kriner, A. G. MacDiarmid, andS. Sujishi, J . Amer. Chem. SOC., 1959, $1, 4493.25 E. C. Even, W. 0. Freitag, W. A. Kriner, and A. G. MacDiarmid, J . Amer. Chem.SOC., 1959, 81, 5106.26 G. W. Campbell and J. Johnson, J . Amev. Chem. Soc., 1959, 81, 3800.27 T. D. Coyle, H. D. Kaesz, and F. G. A.Stone, J . Amer. Chem. SOC., 1959,81, 2989.26 7. Iyoda and I. Shiihara, Bull. Chem. SOC. Japan, 1959, 32, 304.29 L. H. Long and M. G. H. Wallbridge, Chem. and Ind., 1959, 295.30 E. C. Ashby, J . Amer. Chem. SOC., 1959, 81, 4791.s2 J. Goubeau and H. Kallfass. 2. anorg. Chem., 1959, 299, 160.33 G. Kodama, R. W. Parry, and J. C. Carter, J . Amer. Chem. SOC., 1959, 81, 3534.C . E. Nordman and C. R. Peters, J . Anzer. Chem. Soc., 1959, 81, 3551116 IN OKG AN TC CI1 r? &I T ST R Y .ordered nionoclinic form at lower temperatures. The molecules of bothmodifications contain a triangle of boron atoms with a non-coplanar NH,group at one corner; the arrangement of hydrogen atoms suggests that theB,H7 group is a strongly distorted fragment of the B4H10 molecule, but thealternative description of the compound H,N-B,H, as a bridge-substituteddiborane, (H,NBH,)B2H5, cannot be eliminatedxThe dipole moment of tetraborane is 0.56 4 0.1 D .~ The complexkinetics of deuterium exchange between B2D, and B4H10 have been studied;boron atoms also exchange, but detailed investigations have not yet beenreported.36 A polyhorane carbonyl B4H,C0 has been obtained by thesealed- t ube reactionBZH,, + 2CO ___) BkHaCO + BHSCOat 25", and its vapour pressures have been rec0rded.~7A compound of formula B2H203 has been identified as an intermediatein the partial oxidation of the borane B5H,, and the structure (1) is suggestedfor it on the basis of infrared and nuclear magnetic resonance studies.=Hexaborane, B,H,,, results from the complex reactions whichtake place between the pentaborane B,Hll and trimethyl-amine or ethers.= In a mass-spectrometric examination ofa sample of crude tetraborane, evidence for the existence of aheptaborane, perhaps B7H13 or B,H,,, was obtained.40Decaborane forms adducts with one, two, and three mole-compounds with four and five molecules of amine; a t 0" thesecompounds decompose, forming unidentified products.41 It also forms acomplex with three molecules of pyridine which is stable at 105" and doesnot react with trimeth~lamine.~~ Decaborane in acetonitrile can be titratedas a monobasic acid with aqueous alkali,43 but the statement that indimethylformamide it functions as a dibasic acid is incorrect.& The Grignardreagent BloH,MgBr is formed from decaborane and methylmagnesiumiodide in ether; with alkyl fluorides it yields alkyl derivatives of de~aborane.~~In the compound B,,H,,(CH,*CN), acetonitrile molecules replace hydrogenatoms on the two end boron atoms in BloH14; there is little change in theboron framework or in the acetonitrile group when the molecule is formed.46Since the replacement of a hydrogen atom by an acetonitrile group resultsH I /r\ '\y yo B( I )I cules of dimethylamine, and phase studies provide evidence for34 C .E. Nordman and C. Reimann, J . Amer. Chem. SOC., 1959, 81, 3538.35 J. R. Weaver, C. W. Heitsch, and R. W. Parry, J . Chem. Phys., 1959, 30, 1075.36 J. E. Todd and W. S. Koski, J . Amer. Chem. SOC., 1959, 81, 2319.37 A. B.Burg and J. R. Spielman, J . Amer. Chem. SOC., 1959, 81, 3479.38 J. F. Ditter and I. Shapiro, J . Amer. Chem. SOC., 1959, 81, 1022.39 J. L. Boone and A. B. Burg, J . Amer. Chem. Suc., 1959, 81, 1766.40 R. W. Schaefer, K. H. Ludlum, and S . E. Wiberley, J . Amer. Chem. SOC., 1959,41 S. J. Fitch and A. W. Laubengayer, J . Amev. Chem. SOC., 1958, 80, 5911.4a L. Burkhardt and N. R. Fetter, Chem. and I n d . , 1959, 1191.43 R. W. Atteberry, J . Phys. Chem., 1958, 62, 1458.44 J. V. Griffiths and R. L. Williams, Chem. and I n d . , 1959, 655.45 J. Gallaghan and B. SiegeI, J . Amer. Chem. SOC., 1959, 81, 504.46 J. van der M. Reddy and W. N. Lipscomb, J . Chem. Phys., 1959, 31, 610.81, 3157SHARPE: TYPICAL ELEMENTS. 117in the addition of an electron, the compound is formulated electronicallyas (2).The acetonitrile may be displaced by diethylcyanamide or triphenyl-phosphine or may add primary amines across the CZN bond to give C-sub-stituted imine derivatives of decaborane (3),1. - - +CH,~Lt:N-B,,H,,-N~C-CH, (2)+ - - +C H 3-C=N-B,,H ,,-N=C-C H , (3) / I H R I I R HTrimethylamine gives two products, one analogous to the triphenyl-phosphine complex, and the other a benzene-insoluble substance displayingan N-H stretching frequency in the infrared region; this may be a saltcontaining the B,,HIo2- ion.47 The exchange of deuterium between deca-borane and deuterium oxide in dioxan occurs most rapidly with the bridgehydrogen atoms; of the terminal hydrogen atoms, those on boron atomsnumbered 6 and 9 in the decaborane (4) exchange fastest and those onatoms 1 and 3 slowest. Under electrophilic conditions (decaborane incarbon disulphide in the presence of deuterium chloride and aluminiumchloride), exchange takes place at the terminal positions on boron atoms2, 4, 6, 7, 8, and 10, and not in the bridges.483(4)The use of a reduced cobalt oxide on pumice as a catalyst greatly im-proves yields in the synthesis of borazole from ammonium chloride andboron tri~hloride.~~ Tri-B-alkoxytri-N-methylborazoles may be preparedby the action of sodium derivatives of alcohols and phenols on tri-B-chloro-tri-N-methylb~razole.~~ Interaction of boron trichloride and primaryamines 51 yields triamino-derivatives of boron which on pyrolysis affordB-aminoborazoles and then stable polymers of formula (5).Many chemical properties of diboron tetrachloride have been described.Chlorine, bromine, and oxygen cleave the boron-boron bond even below O",with the formation of trihalides and boric oxide; cyanogen is added, formingthe compound B,C1,,1*5C,N2 (boron trichloride combines with 0.5 or 1 moleof cyanogen) ; phosphine forms the stable compound B2C1,,2PH,.Watei-47 M. F. Hawthorne and A. R. Pitochelli, J . Amer. Chem. SOC., 1958, 80, 6685;46 I. Shapiro, M. Lustig, and R. E. Williams, J . Amer. Chem. SOC., 1959, 81, 838;49 H. J. Emele'us and G. J. Videla, J., 1959, 1306.50 M. J. Bradley, G. E. Ryschkewitsch, and H. H. Sisler, J . -4mer. Chem. SOL., 19.59,61 D. W. Aubrey and M. F. Lappert, J., 1959, 2927.1959, 81, 5519.J.A. Dupont and M. F. Hawthorne, ibid., p. 4998.81, 2635118 INOKGANIC CHEMISTRY.effects hydrolysis to the lower boric acid B,(OH), and hydrogen chloride a troom temperature ; at 160", decomposition occurs according to the reactionB&I, + 6H,O + 2H3B0, + 4HCI + H,Hydrogen sulphide combines at low temperatures, giving the adductsB,Cl,,H,S and B2C1,,2H,S, but a t room temperature boron trichloride,hydrogen, and the sulphide B,S, are produced. Dimethyl sulphide, how-ever, forms stable addition compounds B,Cl,,Me,S and B,C14,2Me,S. Thecompound BCl,=SH, the oxygen analogue of which is unknown, is formed asa by-product in the reaction with hydrogen ~ulphide.~, The B-B bondenergy in diboron tetrachloride, obtained from the heat of the reaction withchlorine, the B-Cl bonds in B,Cl, and BCl, being assumed to be identical,is 79 k ~ a l .~ ,Tetrachloroborates and chlorotrifluoroborates of the NO+, PH4+, andorganic cations have been obtained by the interaction of chlorides andboron trichloride or trifluoride in anhydrous hydrogen chloride as solvent .aTri-a-naphthylboron reacts with one equivalent of sodium in tetrahydro-furan to form a paramagnetic solution of the sodium salt of the tri-a-naphthylboron anion ; in diethyl ether a diamagnetic dimeric anion isproduced. The sodium salt in the solid state is diamagnetic (and therefore,presumably, is a polymer); the disodium salt is always diamagnetic, aswould be expected.%The existence of the solvated Ph2B+ cation in ethyl methyl ketonewas reported last year; a solid 2,2'-bipyridyl complex (Ph,Bbipy)ClO, hasnow been obtained from the products of the reactionPh2BCI + AgCIO, __t AgCl+ Ph2BCIOdin nitromethane; 2,2'-bipyridyl is then added, and the complex is precipit-ated by ether.56 Contrary to earlier reports, .boron trifluoride does notform a compound with sulphuric acid; boron trichloride reacts vigorouslywith the acid to give boron tri(hydrogen sulphate), B(HSO,),, a whitedeliquescent powder which combines with sulphuric acid to form the complexacid HB(HS0,),.57Because of their importancein polymerisation catalysts, compounds of aluminium alkyls have continuedto attract attention.58 Infrared studies show that in the systemA1,Me4C1,-TiCl, the compounds Al2Me,C1, and TiMeC1, are present .59Although the Ziegler catalyst which results from the interaction of diethyl-aluminium chloride and biscyclopentadienyltitanium dichloride is the com-pound (C,HJ2TiC1,A1Et,, the presence of an unidentified titanium(1v)species is essential for the polymerisation of ethylene, and the rate of poly-52 E.F. Apple and T. I<. Wartik, J . Amer. Chem. SOC., 1958, 80, 6153, 6155, 6158.53 S. R. Gunn, L. G. Green, and A. I. Von Egidy, J . Phys. Chem., 1959, 63, 1787.54 T. C. Waddington and F. Klanberg, Naturwiss., 1959, 20, 578.55 C . W. Moeller and W. K. Wilmarth, J . Amer. Chem. SOC., 1959, 81, 2638 (cf.56 J. M. Davidson and C. M. French, Chem. and Ind., 1959, 750.57 N. N. Greenwood and A. Thompson, J., 1959, 3643.58 K.Ziegler, Chem. SOC. Special Publ., 1959, N o . 13, 1.59 M. P. Groenewege, 2. phg's. Chem. ( I ; ~ a n k f u ~ l ) , 1958, 18, 147.Aluminium, gallium, indium, and thallium.T. L. Chu and T. J. Weismann, ibid., 1956, 78, 23)SHARI'E: TYPICAL ELEMENTS. j 11)merisatiori can be controlled by regulation of the oxygen content of theet hylene.60 The system tri-isobu t ylaluminium-ti t anium tetrachloride cata-lyses the trimerisation of symmetrical acetylenic compounds to hexa-substituted benzenes .61 Titanium tetrachloride, aluminium, aluminiumchloride, and benzene interact to give the compound Al,TiCl,Ph, probably(6), which effects polymerisation of ethylene and propene.62Gallium trifluoride, obtained by heatingthe metal in hydrogen fluoride a t 500°, isisomorphous with ferric fluoride ; the com-pounds NH,GaF, and NH,AlF, are also [ c'\T,/C'\*,/Ph ] AICI,(6) isomorphous.63 A large number of co-ordination compounds of gallium dichloride(now well established to be Ga+GaCl,-) with ketones, ethers, amines, andother compounds have been described, and have been shown to have thegeneral structure [GaL4] +[GaCl,] -, where L is the monodentate ligand.64Complexes of gallium dibromide are similar.It has been shown that galliumcan take part in heteropolyanion formation, and salts containing the[GaRlo,0,J3- ion have been prepared.G5The only products of the reaction between thallic chloride and sodiumhydroxide in aqueous solution are the hydroxide Tl(OH), and sodiumchloride ; unlike aluminium, gallium , and indium, thallium does not formbasic salts under these conditions.66Group 1V.-A review of the preparation and properties of cyanogen hasbeen given.67 Cyanogen fluoride, concerning the existence of which therehas been much discussion, has been fairly conclusively identified by spectro-scopic methods among the products of the fluorination of cyanogen.68 Anew method for the preparation of cyanogen chloride is the action of chlorineon an aqueous suspension of potassium cyanozincate a t room tem~erature.,~The crystalline compound formed by the polymerisation of hydrogencyanide is a dimer of structure N-C*CH=NH.'OVery pure silicon is obtained by decomposition of silane (made fromsilicon tetrachloride and lithium aluminium hydride) on a hot silicon surfaceby means of radio-frequency heating.'l The mixture of silanes whichresults from the interaction of magnesium silicide and dilute phosphoricacid has been separated by gas-liquid chromatography; nuclear magnetic6o D.S. Breslow and N. K. Newburg, J . Amar. Chenz. Soc., 1959, 81, 81.61 B. Franzus, P. J. Canterino, and R. A. Wickliffe, J . Amer. Chcun. SOC., 1959, 81,62 G. Natta, G. Mazzanti, and G. Pregaglia, Gazzetta, 1959, 89, 2066.63 F. M. Brewer, G. Garton, and D. M. L. Goodgame, J . Inorg. Nuclear Chcm., 1959,64 S. M. Ali, F. M. Brewer, J. Cadwick, and G. Garton, J . Inorg. Nuclear Chem., 1959,65 B. N. Ivanov-Emin and Y . I. Rabovik, Zhur. neorg. Khim., 1958,3,2429; 0. W.66 M. A. Glushkova, Zhur. neorg.Khim., 1959, 4, 1657 [J. Inorg. Chenz. (U.S.S.H.),67 T . K. Brotherton and J. W. Lynn, Chem. Rev., 1959, 59, 841.68 E. E. Aynsley, R. E. Dodd, and R. Little, Proc. Chew. Soc., 1959, 265.69 H. Schroder, Z. anorg. Chem., 1958, 297, 296.i o T. Wadsten and S. Andersson, A d a Chem. Scand., 19.59, 13, 1069.71 J. M. Wilson, Resenrch, 1969, 12, 91.C I / \Cl' ' c ,1514.9, 56.9, 124.Rollins and J. E. Earley, J . Amer. Chem. Soc., 1959, 81, 5571.1959, 4, 7471120 INORGANIC CHEMISTRY.resonance studies show that, in addition to the hydrides already known,two isomers of formula Si,H,, and higher members of the series are present.(Seven products have been shown to be formed in the analogous reactionwith magnesium germanide.72) Monosilane reacts with methanol to yielda mixture of methoxysilanes, the reaction being catalysed by metalliccopper.73 Infrared and Raman spectroscopy show that the configurationround the sulphur and selenium atoms in silyl sulphide and selenide is notlinear; 74 the planar configuration round the nitrogen atom in trisilylaminehas, however, been confirmed.75 Hexamethyldisiloxane, Me,Si*O-SiMe,, isa non-donor solvent, and iodine forms a purple solution in it; aluminiumchloride decomposes it, giving the compounds Me,SiCl and Me,Si*O.AlCl,,and aluminium bromide reacts ~imilarly.7~'' Silicon monoxide," obtained from silicon and silica by quenching thevapour, is found by X-ray investigations to be a mixture of the startingmaterials; 77 this does not, of course, preclude the existence of SiO as anunstable intermediate solid phase.Silicon imide, Si(NH),, may be pre-pared from silicon tetrachloride and liquid ammonia; it decomposes whenheated, forming ill-defined polymers of approximate composition Si,(NH),N,and Si,(NH)N2, then Si3N4.78 A phosphide Si,P is obtained from silane andphosphine a t 450"; it is a blue-black amorphous substance which a t 600"decomposes into silicon and the phosphide SiP.79 The wurtzite form ofsilicon carbide has been obtained80 by the thermal decomposition of tri-chloro(methy1)silane in hydrogen at 1500".It is not possible to review here substantial developments in the organicchemistry of silicon; attention may, however, be directed to a review 81 ofthis subject and to recent papers on polymeric silicon-methylene com-pounds s2 and on the mechanism of substitution a t a four-co-ordinatedsilicon at0rn.8~ The preparation and properties of adducts of amines andsilicon halides (and the corresponding germanium and tin compounds) havebeen described.84As was mentioned earlier, evidence for the existence of higher germaneshas been obtained,72 and a tetra- and a penta-germane have been identifiedamong the products of the action of 10% hydrochloric acid on magnesiumgermanide.= Hexachlorodigermane, Ge,Cl,, may be prepared by the72 K.Borer and C. S. G. Phillips, Proc. Chem. SOG., 1959, 189.73 B. Sternbach and A. G. MacDiarmid, J . Amer. Chem. SOC., 1959, 81, 5109.74 E. A. V. Ebsworth, R. Taylor, and L. A. Woodward, Trans.Faraday SOC., 1959,c5 H. Kriegsnian and W. Forster, Z. anorg. Chem., 1959, 298, 212.'~3 A. H. Cowley, F. Fairbrother, and N. Scott, J., 1959, 717.77 G. W. Brady, J . Phys. Chem., 1959, 63, 1119.78 0. Glemser and P. Naumann, 2. anorg. Chem., 1959, 298, 134.79 G. Fritz and H. 0. Berkenhoff, 2. anorg. Chem., 1959, 300, 205.8o K. M. Merz and R. F. Adamsky, J . Amer. Chew. Soc., 1959, 81, 250.81 D. Wittenberg and H. Gilman, Quart. Rev., 1959, 13, 116.s2 G. Fritz and B. Raabe, 2. anorg. Chew., 1959, 299, 232; G. Fritz and J. Grobe,ibid., p. 302.83 L. H. Sommer and C . L. Frye, J . Amer. Chem. Suc., 1959, 81, 1013; R. H. Prince,.I., 1959, 1783.84 J. E. Fergusson, D. K. Grant, R. H. Hickford, and C. J. Wilkins, J., 1959, 99;E. Bannister and G.W. A. Fowles, J., 1959, 310.85 E. Amberger, Angem. Chem., 1959, 71, 372.55, 211SHA4RPE : TYPICAL ELEMENTS. 121microwave discharge method from germanium tetrachloride vapour.*6Although hexachlorogermanates have been prepared, germanium tetra-chloride (unlike stannic chloride) does not function as an acid in liquidhydrogen chloride.87Conductometric titration of sodium and dimethylstannane in liquidammonia indicates the formation of the compounds SnMe,Na,, SnMe,HNa,and (SnMe,Na),; the last compound, which can be obtained pure and isstable at room temperature, reacts with ammonium bromide to give di-methylstannane and a polymer of empirical formula SnMe,, and withmethyl iodide to give hexameth yldistannane . 88 Trime t h ylplumbane,Me,PbH, is formed in the reaction between trimethylchloroplumbane andpotassium borohydride in liquid ammonia a t -33"; the compoundMe,PbBH,, from which ammonia subsequently removes a borane group, isprobably first pr0duced.8~ Trimethylplumbane decomposes above - loo",probably forming methane and the hydride Me,Pb*PbMe,H.Tetramethyl-lead reacts with pentafluoroethyl iodide under the influence of heat or ultra-violet light to give the compound Me,PbC,F,.SoA structure of outstanding interest is that of bisthiourealead(I1) chloride,in which the lead atoms are seven-~o-ordinated.~~ Each lead atom has 2sat 3-02, 2s at 2.92, and 2Cl at 3-17 A; all of these are shared with neigh-bouring lead atoms in a chain polymer, and the configuration round thelead is roughly that of a trigonal prism; in addition, each lead has onemore chlorine atom (not shared) near the centre of a lateral face of theprism, at a distance of 2.75 A.Solid ammonia has an approximately face-centredcubic structure, the lone pair of electrons apparently being involved inhydrogen bonding to three other molecules ; this precludes the possibilityof inversion of the molecule in the solid state, a conclusion also supportedby infrared spectroscopic evidence.s2 Ammonia hydrate, NH,,H,O, con-tains chains of water molecules linked by hydrogen bonds of length 2-78 A;these chains are cross-linked by ammonia molecules into a three-dimensionalnetwork by 0-H - - N and 0 .- H-N bonds of length 2-78 and 3.25 (meanvalue) , respe~tively.~~ Glow-discharge electrolysis of liquid ammonia,ammonium nitrate being used as an inert electrolyte, leads to the productionof h y d r a ~ i n e .~ ~ A phase study9* of the NH,-H,O, system shows theexistence of two compounds, NH,,H,O, (m. p. 24") and 2NH,,H,O, (whichmelts incongruently a t -133").Tetrafluorohydrazine, first made by the heterogeneous reduction ofnitrogen trifluoride with metals, is also produced, together with difluorodi-imine, N,F,, in the homogeneous reaction of the trifluoride with mercuryGroup V.-Nitrogen.R6 D. Shriver and W. L. Jolly, J . Amer. Chevn. SOC., 1958, 80, 6692.87 T. C . Waddington and F. Klanberg, Naturwiss., 1959, 20, 578.88 S. F. Kettle, J., 1959, 2936.8Q R. Duffy and A. K. Holliday, Proc. Chem. Soc., 1959, 124.no H.D. Kaesz, J. R. Phillips, and F. G. A. Stone, Chem. and Ind., 1959, 1409.91 M. Nardelli and G. Fava, Acta Cryst., 1959, 12, 727.w I. Olovsson and D. H. Templeton, Acta Cryst., 1959, 12, 827, 832.93 A. Hickling and G. R. Newns, Proc. Ghern. SOC., 1959, 272, 368.94 K. E. Mironov, Zhur. neorg. Khim., 1959, 4, 153 u. Inorg. Chem. (U.S.S.K.),1959, 4, 621122 ZNORGANIC CHEMISTRY.in an electric discharge.95 Difluorodi-imine is also obtained, with nitrogentrifluoride, by electrolysis of ammonium fluoride in anhydrous hydrogenfluoride; cis- and trans-forms can be separated by distillati~n.~~ The com-pound reacts with acidified iodide solution :NZF, + 21- N, + 12 + 2F-Difluoroamine, NHF,, has been obtained as one product of the fluorinationof urea,97 or, in small amounts, by the reaction between nitrogen trifluorideand arsenic at 250-300" (the source of the hydrogen is not menti~ned).~~It melts at -116", boils at -23.6", and is explosive; aqueous hydriodicacid decomposes it rapidly:NHF, $- 4HI 21, -t NHdF 3- HFAttempts to repeat Ruff and Staub's preparationg9 of the compound byelectrolysis of ammonium hydrogen fluoride have not been succe~sful.~~A review of the inorganic azides has been given,100 and the mechanismof the azide-nitrite reaction has been studied.lO1 In the presence of excessof perchloric acid at 0" there are two mechanisms:N,-NO,- + H,NO,+ N20, + H,O -% N,*NO +- NO2- N2 4- N20slow fast fastHN, + H,NO,+ __t N,*NO + H,Of -+ N, + N,Oslow fastIn a sodium azide-hydrazoic acid buffer the rate-determining step isN3-+ H,NO,+ __f N3*N0 -b H20slowand is followed by rapid decomposition of the nitrosyl azide.Oxygenexchange between nitrous acid and water proceeds via the formation ofdinitrogen trioxide a t high concentrations and via the formation of theH,NO,+ ion at low concentrations.lo2 The structure of dinitrogen trioxidehas been discussed, and it is concluded that it is O,N*NO with a x-onlyN-N bond.lNElectrical conductance and transport measurements show that dinitrogentetroxide in nitric acid is almost completely dissociated into NO+ and NO,-ions.lW Several new salts of the NOf ion, including those of condensedphosphoric acids lo5 and fluoro-acids of Group IV elements,lo6 have beendescribed.An outstanding contribution to the literature of phosphorus Phosphorus.95 J, W.Frazer, J. Inorg. Nuclear Chem., 1959, 11, 166.D6 M. Schmeisser and P. Sarton, Angew. Chem., 1959, 71, 623.97 E. A. Lawton and J . Q. Weber, J. Amer. Chem. SOC., 1959, 81, 4755.98 A. Kennedy and C. B. Colburn, J. Amer. Chem. SOC., 1959, 81, 2906.99 0. Ruff and L. Staub, Z. anorg. Chem., 1931, 198, 32.100 B. L. Evans, A. D. Yoffe, and P. Gray, Chem. Rev., 1959, 59, 515.lol G. Stedman, J., 1959, 2943, 2949.102 C. A. Bunton, D. R. Llewellyn, and G. Stedman, J., 1959, 568; C. A. Bunton103 J . Mason (Banus), J., 1959, 1288.l o 4 J. D. S. Goulden, W. H. Lee, and D. J . Millen, J., 1959, 734.lo5 F. Seel, R. Schmutzler, and K. Wasem, Angew. Chem., 1950, 71, 340.lo6 P.Bouy, Ann. Chim. (France), 1959, 4, 853.and G. Stedman, J., 1959, 3466SHARPE TYPICAL ELEMENTS. 123chemistry has been the publication of Volume I of Van Wazer's b00k,l07which includes a full and authoritative account of the oxyacids and theirsalts. Other reviews dealing with various aspects of the chemistry of theelement include those on condensed phosphates,loS metal complexing byphosphates ,log and the phosphonitrilic ha1ides.ll0A yellow solid hydride, (PH),, is obtained, together with some phosphinc,by the action of lithium hydride on phosphorus trichloride or tribromide inether, preferably a t -30". The compound is insoluble in all the usualsolvents; when heated ifi vaczco at 500°, it decomposes into phosphorus andphosphine.lll The chloride P,C14 has been obtained by mercury-dischargereduction of the trichloride and condensing out the white solid a t -45";it melts at -35" and decomposes a t room temperature, forming the tri-chloride and non-volatile yellow solids.Attempts to replace the chlorineby fluorine were unsuccessful.l12 The physical properties of the mixedhalide PCl,F, have been re-examined, and it has been shown 113 that itundergoes a slow transformation into the ionic form PCl,+PF,-.The cyclic polymers (CF,P), and (CF,P), (m. p. 66" and -33", b. p. 145"and 190", respectively) are made by the action of mercury on the com-pound CF,PI, at room temperature, or (together with higher polymers)by pyrolysis of P2(CF,)4 or (CF,),PH at 350"; the pentamer is largely con-verted into the more stable tetramer when it is heated.Oxygen reactswith the tetramer in a fluorocarbon solvent to form polymers of formula(CF,PO,), ; hydrolysis under suitable conditions yields the new phosphines(CF,PH), and H2(CF,P), from the tetramer and pentamer re~pective1y.l~~When heptafluoroiodopropane is heated with phosphorus at 200", the com-pounds (C,F,)PI, and (C,F,),PI, but no (C,F,),P, are formed; severalderivatives of them have been described.l15Trimeric phosphonitrilic chloride has an almost planar molecule withLClPCl= 102", LNPN = 120°, P-N = 1.57 h;, and P-C1= 1.98 A.11sMethylphosphonitriles, (Me,PN),, of which the trimer and tetramer havebeen characterised, have been made from trichlorodimethylphosphorane ,Me,PCl,, and ammonium chloride ; 117 they are remarkable among phospho-nitrile derivatives in that they dissolve in cold water without decompositionand decompose, instead of polymerising to a rubber, at 350400".Trimericand tetrameric diamidophosphonitriles, [PN(NH,)& and 4, are formed whenethereal solutions of the chlorides are slowly added to excess of liquidammonia and the resulting solution is stirred for several hours; they arewhite hygroscopic substances which decompose when heated, with liberationlo' J. K. Van Wazer, " Phosphorus and Its Compounds," Interscience Publ. Inc.,New York, 1958, Vol. I.lo8 E. Thilo, Naturwiss., 1959, 46, 367.lo9 J. R. Van Wazer and C. F. Callis, Chem. Rev., 1958, 58, 1011.110 N. L. Paddock and H. T. Searle, " Advances in Inorganic Chemistry and Radio-chemistry," 1959, 1, 348; R.A. Shaw, Chem. and Ind., 1959, 412.111 E. Wiberg and G. Muller-Schiedmayer, Ber., 1959, 92, 2372.112 A. Finch, Canad. J . Chem., 1959, 37, 1793.lls T. Kennedy and D. S. Payne, J . , 1959, 1228.114 W. Mahler and A. B. Burg, J . Arner. C h e w SOL, 1958, 80, 6161.115 H. J. Emel6us and J. D. Smith, J., 1959, 375.116 E. Cipollini, F. Pornpa, and A. Ripamonti, Ricercu sci., 1958, 28, 205.5.11' I T . T. Searle, R o c . Chcnz. SOC., 1959, 7124 INORGANIC CHEMISTRY.of ammonia. They are soluble in, but slowly decomposed by, water. Thetrimer has been identified among the products of the reaction betweenphosphorus pentachloride in chloroform and liquid ammonia at -50°, andit is likely that the amides are intermediates in the synthesis of the phospho-nitrilic ch1orides.lls Trimeric phosphonitrilic chloride reacts with tri-methylamine at room temperature, yielding tetramethylammonium chlorideand a solid of approximate composition [PNClo.,s(NMe2)l.,2]3; no similarreaction occurs with triethylamine or pyridine.Sodium acetylide replacedsome of the chloride by a~ety1ide.l~~ In a new synthesis of the trimeric andtetrameric fluorides,12* the compounds P3N5 and CF3*SF, or NF, are allowedto react a t 700”.The preparation of phosphinoborine polymers has been briefly described :thermal decomposition of the monoborane adduct of tetramethyldiphosphanegives the trimer and tetramer, and a higher chain polymer, of empiricalcomposition Me,PBH,; a similar chain polymer is obtained from the com-pound Me,PH,BH, in the presence of triethylamine at 200”.Other alkyl-phosphanes behave similarly.121A polymeric oxide (PO), may be obtained by electrolysis of triethyl-ammonium chloride in phosphorus oxychloride at 0” between platinumelectrodes (it is then deposited as a brown solid at the cathode), or by boilingphosphorus oxybromide in dry ether with magnesium. The analogoussulphide is produced similarly from phosphorus thiobromide and magnesium ;it is hydrolysed by alkali to phosphorus, hypophosphite, and sulphide.lZ2The oxidation of phosphorus vapour in the presence of moisture leads tothe formation of an orange substance of empirical formula P,OH, suggestedto consist of a polymeric network of phosphorus atoms with some hydroxylgroups attached.12,Hypophosphates are stable to aqueous alkali, but the action of moltenalkali results in the formation of orthophosphate; cupric ion-catalysedoxidation by hypobromite yields a mixture of ortho- and(7)pyro-phosphate.(8)Hyyochloritc oxidation of red phosphorus in the presence of alkali gives riseto salts of a new acid H,P,O,,, the structure of which appears to be (7).Oxidation of this with iodine in a bicarbonate buffei- results in the formationof an acid believed to be (8).12* The rate of exchange of the hydrogen atomL.F. Audrieth and D. B. Sowerby, Chew. and I n d . , 1959, 748.119 A. B. Burg and A. P. Caron, J . Amer. Chem. SOL, 1959, 81, 836.120 T. J. Mao, R. D.Dresdner, and J. A. Young, J . Amer. Chem. Soc., 1959, 81, 1020.A. B. Burg, J. Inorg. Nztclear Chew., 1959, 11, 258; R. 1. Wagner and F. F.(‘aserio, ibid., p. 259.122 W. Kuchen and H. G. Beckers, Angela. Cheni., 1959, 71, 163; H. Spantlau antiA. Beyer, Naturwiss., 1959, 46, 400.lZ3 H. Harnish, 2. aPzorg. Chem., 1959, 300, 261.12* 13. Blaser and K.-H. Worms, 2. anopg. Chem., 1959, 300, 229, 237, 260STTARPR TYPICAL ELEMENTS. 1%bonded to phosphorus in phosphorous acid with deuterium oxide has beenfollowed by Raman spectroscopy; it increases with increase in the acidityof the solution, suggesting that formation of species such as H,DPO3+ isinvolved; in solutions of salts of the acid, exchange is very slow.125The reaction between phosphoric oxide and ammonia yields mainlyderivatives of pyrophosphoric acid; the action of heat then produces anammonium polyphosphate in which phosphorus atoms are joined halfthrough oxygen atoms and half through -NH- groups.lZ Phosphorictrihydrazide, OP(N,H,),, is obtained by the action of phosphorus oxy-chloride in ether on anhydrous hydrazine in ethereal suspension.127 Theacid HP02Cl, is formed when the oxychloride P,03C14 (made by heating amixture of molar composition 4Poc1, : P,O, a t 200') is cooled to -30" andtreated with the calculated quantity of water.12sFused orthophosphoric acid absorbs 1.08 moles of boron trifluoride a troom temperature with liberation of heat; the absorption results in adecrease in both the viscosity and the electrical conductivity. This isbelieved to be due to a reduction in the extent of hydrogen bonding and tothe replacement of a proton-switch conduction mechanism by normal ionicmig1-ati0n.l~~ Paper chromatography leads to the conclusion that knowncrystalline calcium phosphates in the polyphosphate region all containunbranched-chain anions; the mixed salt of formula Na,CaP,018 is a tri-metaphosphat e Na,Ca (P,O,) ,A review of the history of '' phosphorus trisulphide, P2S3 " leads to theconclusion that there is no evidence for the existence of this substance as astable phase.131 When tetraphosphorus trisulphide addsIP+S iodine to form the compound P,S31,, the P4S3 skeleton isI s 1 partly broken and the structure of the product is (9).13, The(9) selenide P,Se3 is isomorphous with the low-temperature formof the corresponding ~u1phide.l~~Arsine reacts with sodium and lithiumamides in liquid ammonia to give derivatives of formulze NaAsH, andLiAsH,; both form di- and tetra-ammoniates.In the absence of a solventthe products are ammonia and solids of approximate compositionNa,AsH and L ~ , A s H . ~ ~ ~ The compounds (CF,),As*NH,, [(CF,),As],NH,(CF,),As*NHR (R = Me or Et), and (CF,),As*NMe, have been made by theinteraction of chlorobistrifluoromethylarsine and ammonia or amines.l%Potassium meta-arsenate, which exists in three forms stable at differenttemperatures, is formed on dehydration of potassium dihydrogen a r ~ e n a t e . l ~ ~'The y-form, stable at room temperature, contains linear chain anions ofs, ;,PIArsenic, antimony, and bismuth.125 R.B. Martin, J . Amer. Chem. SOC., 1959, 81, 1574.126 M. Becke-Goehring and J. Sambeth, 2. anorg. Chertz., 1958, 297, 287.1-27 R. Klement and K. 0. Knollmiiller, Nuturwiss., 1958, 45, 515.I z 8 H. Grunze, 2. anorg. Chem., 1959, 298, 152.129 N. N. Greenwood and A. Thompson, J., 1959, 3493.I3O S. Ohashi and J. R. Van Wazer, J . Amer. Chem. SOC., 1959, 81, 830.131 A. R. Pitochelli and L. F. Audrieth, J . Amer. Chem. SOC., 1959, 81, 4458.132 D. A. Wright and B. R. Penfold, Acta Cryst., 1959, 12, 465.133 E. Kewlen and A. Vos, Acta. Cryst., 1959, 12, 323.134 W. L. Jolly, J . Amer. Chem. SOC., 1959, 81, 1029.135 W. R. Cullen and H. J. EmeEus, J . , 1959, 372.136 E. Thilo ant1 I<. DostAl, Z.anorg. Chenz., 1959, 298, 100I26 INORGANIC CHEMISTRY.high molecular weight ; from mixtures of the dihydrogen arsenate and thedihydrogen phosphate products containing arsenic and phosphorus atomsstatistically distributed are obtained.The methylstibines MeSbH, (very unstable) and Me,SbH are obtainedby the interaction of dimethylbromostibine and sodium borohydride indiethylene glycol dimethyl ether (" Diglyme ',). Dimethylstibine reactswith hydrogen chloride, liberating hydrogen, or with the compound B,H,Br,liberating diborane. Tetramethyldistibine, Sb,Me,, reacts with diboraneat 100" to give the compound Me,Sb*BH,; this does not form a complexwith trimethylamine, but when heated with this compound it decomposes,yielding trimethylamine-borine, Me,N,BH,, as the main product. It showsno tendency to polymerise, and the general lack of reactivity has beentaken to indicate the existence of x-bonding between the antimony andboron atoms.137the molecule is atrigonal bipyramid with Sb-C1 (apical) = 2-34 and Sb-C1 (basal) = 2-29 A.In the addition compound POCl,,SbCl, the oxygen of the phosphorus com-pound occupies one of the octahedral positions round the antimony andLSbOP is 144"; this is the first determination of the structure of acomplex in which an oxychloride is the donor.139 Antimony pentachloridehas also been shown to form stable complexes with sulphoxides and sul-phones.140Melting-point depression and vapour-pressure data suggest that the ionBiz2+ is present in molten bismuth trihalide-bismuth systems.141 Measure-ment of the vapour pressure of bismuth trichloride over bismuth mono-chloride and over pure bismuth trichloride shows that the solid mono-chloride is barely stable with respect to its solid disproportion p r 0 d ~ c t s .l ~ ~The structure and semi-conducting properties of bismuth telluride have beenreviewed.laGroup VI.-The densities of solid and liquid ozone at 77.4" K are 1-728and 1.614 respectively.lU The existence of the fluoride O,F, has been con-firmed; it is obtained by the action of an electric discharge on a mixture ofoxygen and fluorine at 77" or 90" K and 12 mm. pressure as a blood-redcompound (m. p. 83" K) which decomposes a t 116" K to oxygen and di-fluorine d i 0 ~ i d e . l ~ ~ Spectrophotometric and electron-spin resonance in-vestigations support earlier evidence that the alkali-metal ozonides containthe 0,- ion, and also show that this ion is probably formed during thedecomposition of hydrogen peroxide in alkaline media.146Sulphur tetrafluoride can be made by the action of sulphur dichlorideon sodium fluoride suspended in acetonitrile at 70-80"; a large number ofAntimony pentachloride forms a molecular lattice;137 A.B. Burg and L. R. Grant, J . Amer. Chenz. SOL, 1959, 81, 1.138 S. M. Ohlberg, J . Amer. Chem. Soc.. 1959, 81, 811.139 I. Lindqvist and C.-I. Brand&, Acta Cryst., 1959, 12, 642.140 I. Lindqvist and P. Einarsson, Ada Chem. Scand., 1959, 13, 420.141 M. A. Bredig, J . Phys. Chem., 1959, 63, 978.142 A. J. Darnel1 and S.J. Yosim, J . Phys. Chem., 1959, 63, 1813.143 D. A. Wright, Research, 1959, 12, 300.144 A. G. Streng and A. V. Grosse, J . Amer. Chein. SOC., 1959, 81, 805.145 A. D. Kirshenbaum and A. V. Grosse, J . Amer. Chem. SOC., 1959, 81, 1277.146 A. D. McLachlan, M. C. R. Symons, and M. G. Townsend, J., 1959, 952SIIAKPJ? : TYP1C:UA I<LICTtIl~N'l'S. 127its reactioiis with organic compounds have been studied.147 Nuclearmagnetic resonance studies confirm that sulphur and selenium tetrafluorideshave the CzV rather than the tetrahedral structure, and show that the rateof fluorine exchange between the apical and equatorial positions increasesin the order SF, < SeF, < TeF,.la Pentafluorosulphur hypofluorite hasbeen shown 149 by electron diffraction to have the structure F,SOF withthe average S-F distance 1.53, O-F 1-43, and 0-S 1.64 A.Peroxydisulphurylfluoride, S206F2, reacts with sulphur dioxide to yield the new compoundS308F2, a liquid, for which the structure F*S02*O*S02~O*S0,F is suggested.150Microwave spectroscopy has been used 151 to show that (' sulphur mon-oxide " (formed by the action of an electric discharge on a mixture of sulphurand sulphur dioxide) is in fact disulphur monoxide having the surprisingstructure SSO with S-S = 1.88, S-0 Liquidsulphur dioxide as a solvent has been further studied: 152 the exchange of35S between the solvent and thionyl chloride is catalysed by antimonypentachloride, an intermediate compound SOC12,SbC15 being formed.Catalysis of the exchange by tetramethylammonium chloride is preventedby addition of antimony pentachloride, the compound Me,NSbC16 beingformed preferentially. Anhydrous thiosulphuric acid, which is very un-stable, has been obtained by the interaction of hydrogen sulphide and sulphurtrioxide in the absence of a solvent or in a freon at -78", or by the actionof hydrogen sulphide on chlorosulphonic acid a t the same temperature.153The action of sulphur trioxide on a solution of the compound H2S6 in amixture of ether and carbon disulphide at -78" leads to the formation of theacid H2S703, which reacts further with sulphur trioxide thusH2S,O, + so, + H,S,O,and is oxidised by chlorine or iodine to a polythionic acid of formulaH2S,,06.154 Thionyl cyanide, which is unstable, results from the action ofthionyl chloride vapour on freshly precipitated silver cyanide.l= The com-pound NH,SO,, formerly believed to be the amide of permonosulphuric acid,has been shown 156 by infrared and nuclear magnetic resonance spectroscopyto be the zwitterion H3N+*O*S0,-.The compound S7NH is well known; the di-imide S,(NH),, obtained asa by-product in the action of ammonia on disulphur dichloride, has nowbeen separated by adsorption chromatography on alumina.It is a colour-less solid, soluble in organic solvents but not in water, which melts withdecomposition a t about 140"; the relative positions of the imide groups1.46 A, and LSSO = 118".147 W. C. Smith, C. W. Tullock, E. L. Muetterties, W. R. Hasek, F. S. Fawcett,14* E. L.Muetterties and W. D. Phillips, J . Amer. Chem. Soc., 1959, 81, 1084.14* R. A. Crawford, F. B. Dudley, and K. Hedberg, J . Amer. Chem. SOL, 1959, 81,I5O J. E. Roberts and G. H. Cady, J . Amer. Chem. SOL, 1959, 81, 4166.151 D. J. Meschi and R. Y . Myers, J . Mol. Spectroscopy, 1959, 8, 405.154 D. E. Burge and T. H. Norris, J . Amer. Chem. SOC., 1959, 81, 2324, 2329.153 M. Schmidt and G. Talskp, B e y . , 1959, 92, 1526, 1539.Is4 M. Schmidt and H. Dersin, %. hratzirforsch., 1959, 14b, 735.lS6 U. Wannagat and R. Pfeiffenschneider, 2. anorg. Chem., 1958, 297, 151 ; R. E.V. A. Engelhardt, and D. D. Coffman, J . Amer. Chem. SOC., 1959, 81, 3185.5387.P. W. Schenk and H. Bloching, Ber., 1959, 92, 2333.Richards and R. W. Yorke, J . , 1959, 28211% J NO K C; AN 1C C TI E M 1 S'TRY,have not yet been e~tablis1ied.l~~ Sulphur nitride suspended in carbon-tetrachloride reacts with chlorine to give the compound S,N,Cl,, which isconverted by silver difluoride into the fluoro-compound S,N,F,.Bothcompounds are quantitatively hydrolysed by alkali to ammonia, sulphite,and halide; the structures (10; X = C1 or F) are suggested.15* Thechemistry of the sulphur nitrides and related compounds has been re-viewed.159 The interesting compound (Ag,S)NO,, best madefrom silver nitrate and carbon disulphide, contains aninfinite-chain cation, each sulphur atom being surroundedby six silver atoms in a distorted octahedron.l60by the action of hydro-gen on molten technical selenium a t 650", followed bydecomposition of the resulting hydrogen selenide at 1000".Fluorination ofselenium dioxide and oxychloride gives small yields of the compoundsF,Se-OF and F,Se*O*O*SeF,; the former is decomposed by water to oxygen,selenate, and fluoride, but the latter is inert.l@ The compound SeOCI,,Bpyhas a tetragonal pyramidal configuration round the selenium atom ; the oxygenatom occupies the apical position and chloride atoms and pyridine moleculestake up trans-positions in the basal plane; the molecules show a slighttendency to dimerisation by formation of weak chlorine bridges to othermolecules, thus giving the selenium atom a grossly distorted octahedral con-fig~rati0n.l~~ Selenium dioxide forms bright yellow solutions in sulphuricacid and is partially protonated to give [HSeO,]+[HSO,]- ; tellurium dioxideis ins01uble.l~~Group V1I.-Several addition compounds of chlorine trifluoride, iodineheptafluoride, sulphur tetrafluoride, or sulphur oxytetrafluoride, SOF,, andboron trifluoride, arsenic pentafluoride, or antimony pentafluoride havebeen described, those of boron trifluoride being the least, and those ofantimony pentafluoride the most, ~ t a b 1 e .l ~ ~ These addition compounds aredecomposed by potassium fluoride, e.g.,XNI IN/s\XS,N/SX( 1 0) Pure selenium may be madeSF,,BF8 + KF KBF, + SF,Studies of the temperature- and pressure-dependence of the infrared spectraof mixtures of hydrogen fluoride and chlorine trifluoride, sulphur dioxide ,carbon dioxide, carbonyl sulphide, or nitrogen indicate the formation of1 : 1 molecular complexes similar to those formed from hydrogen chlorideand sulphur dioxide or carbon dioxide.lssThe monohydrate of hydrogen chloride has been shown167 by X-ray167 J.Weiss, Angew. Chem., 1959, 71, 246.158 H. Schroder and 0. Glemser, Z. anorg. Chem., 1959, 298, 78.1.59 M. Becke-Goehring, " Progress in Inorganic Chemistry," 1959, 1, 207.I6O G. Bergerhoff, 2. anorg. Chem., 1959, 299, 328.161 S. Nielsen and R. G. Heritage, J . Electrochem. SOC., 1959, 106, 39.lea G. Mitra and G. H . Cady, J . Amer. Chem. SOL. 1959, 81, 2646.16s I. Lindqvist and G. Nahringbauer, Acta Cryst., 1959, 12, 638.164 R. H. Flowers, R. J. Gillespie, and E. A, Robinson, J . Inorg. Nuclear Chem.,165 F. See1 and 0. Detmar, 2.anorg. Chem., 1959,301, 113; F. A. Cotton and J. W.16' Y. I(. Yoon and G. R. Carpenter, Acta Cryst., 1959, 12, 17.1959, 9, 155.George, J . Inorg. Nuclear Chem., 1958, 7, 397.T. G. Burke and D. F. Smith, J . MoE. Sfiechoscopy, 1959, 8, 381SHARPE: TYPICAL ELEMENTS. 129analysis at -35" to be H,O+Cl-, each hydrogen atom being hydrogenbonded to the nearest chlorine, with 0-H - C1 2.95 A. The variation ofthe C1-0 bond length with change in the co-ordination number of the chlorinein the series of ions C10,-, ClO,-, and C10,- has been discussed : in ammon-ium chlorite, C1-0 is 1.57 k and LOClO 110", whereas in ClO,- the C1-0distance is only 1.44 A.Further work on the very unstable oxides of bromine has been re-ported; 169 the interaction of ozone and bromine has been stated to yieldthe oxide Br,O, in Pyrex, and (Br30& in quartz, apparatus.In trichloro-fluoromethane at -80" bromine dioxide is said to be formed.170 Brominetrinitrate, Br(NO,),, is reported171 to be formed by the interaction ofbromine trifiuoride and &nitrogen pentoxide in the same solvent at -30".A timely review of the structures of interhalogen compounds and poly-halides has been given by Havinga and Wiebenga,172 and important newwork an these substances has been published. The compound Me,NHBr, is[Me3NH] +2Br-Br3-.173 In tetraphenylarsonium tri-iodide the anion issymmetrical, with 1-1 = 2-90 A; 174 in tri-iodides of smaller cations the LIIIis the same (176") but the anion is by no means symmetrical. In the com-pound Me,NI, the nitrogen and iodine atoms are collinear, N-I being2.27 A and 1-1 2-83 A (0.17 longer than in molecular iodine).175 Thecompounds ISbCl, and IAlCI, contain IC&+ and SbC1,- or AlCl,- ions; theIC12+ ion is bent, with LClICl = 92.5" and 96.7" respectively. Eachiodine, however, has four chlorine atomsI I as near neighbours, the environment inshown in (11).These structures arerather like that of iodine trichloride;like the latter compound, ISbCl, is amoderately good conductor in the fusedstate ( K = lo-, ohmw1 cm.-l at 100'). Theequivalent conductivity in liquid sulphurdioxide is only 2% of that of potassiumhexachloroantimonate, suggesting disso-ciation in this solvent mainly into molecules.176Several new compounds containing bromine or iodine cations stabilisedby formation of complexes with pyridine have been prepared : the action ofbromine or iodine on dipyridinesilver fluoroantimonate, Ag(py),SbF,, indry acetonitrile at 0" gives the compounds Br(py),SbF6 and I(py),SbF,;,Cl-Al - .I the aluminium compound being as -At - CI,I2-86'>. n a"2.86', 85.3O ,a'9 0.6" I *,89 . I .\CI2.29 /.,y ( ' ' 2.26CI( 1 1)168 R. B. Gillespie, R. A. Sparks, and K. N. Trueblood, Acta Cyst., 1959, 12, 867.169 A. J. Arvia, P. J, Aymonino, and H. J. Schumacher, 2. anorg. Chem., 1959,170 M. Schmeisser and K. Joerger, Angew. Chem., 1959, 71, 623.171 M. Schmeisser and L. Taglinger, Angew. Chem., 1959, 71, 523.173 E. E. Havinga and E, €3. Wiebenga, Rec. Trav.chim., 1959, 78, 724.173 C. Romers and E. W. M. Keulemans, Proc. K. ned. Akad. Wetenschap., 1958,174 R. C. L. Mooney Slater, AcEa Cryst., 1959, 12, 187.175 K. 0. Stramme, Acta Chenz. Scand., 1959, 13, 268.176 C. G. Vonk and E. H. Wiebenga, Actu Cryst., 1959, 12, 867; Rec. Trav. chim.,298, 1.61, B, 345.1959, 78, 913.REP.-VOL. LVI z 30 INORGANIC CHEMISTRY.Br(py),F and I(py),F are obtained similarly from silver fluoride and yyridinein a~etonitri1e.l'~ In chloroform, however, iodine, pyridine, and silverfluoride are reported to give I(py)F; silver cyanide and the same reagentsyield the monopyridine adduct of iodine cyanide ; the infrared spectra ofthe compounds have been studied.178 The proton nuclear resofiancespectrum band for solutions of iodine in oleum is much broader than that foroleum alone, and is shifted to higher fields, the shift and broadening beingroughly proportional to the concentration of iodine.These changes areinterpreted in terms of the formation of a paramagnetic species of momentabout 1.5 B.M. and it is suggested that this is the iodine cation; the " spin-only " value for I+ with the electronic configuration 5s25P4 would, of course,be 2-83 B.M., but there is no compelling reason for assuming this value, sinceions of the heavier elements usually have moments which differ from thosecalculated on the " spin-only " basis.179 A comparison of the infraredspectra of several complexes of iodine cyanide (e.g., with benzene, ethanol,quinoline) shows that the decrease in the I-C stretching frequency is greatestfor the best donors; the C-N frequency, however, is little affected.lsOIodine, like silver ion, forms complexes with many cyclic olefins; theheats of complex formation in 2,2,4-trirnethylpentane are in the region of0.5-3-0 kcal./mole.lsl Formation constants for iodine-olefin complexesshow less dependence on ring size than those for silver-olefin complexes, afact which may indicate a difference in structure such as is already estab-lished for complexes of iodine or silver and aromatic hydrocarbons.The oxides I,O, and 1204 combine with sulphur trioxide to form thecompounds 1205,2S03 and 1204,3S0,, respectively; it is possible that thesemay have the structures (I02),S,07 and (10) (102)S,010.182 There is, how-ever, at present no evidence for the existence of the 102+ ion : iodyl fluoridedoes not combine with boron trifluoride in a manner analogous to nitryl andchloryl fl~orides.18~ The first product of the dehydration of periodic acidis reported to be the compound H71,014.184The preparation of the interesting compound CF,*IF2, by addition OCfluorine to trifluoroiodomethane in a freon solvent at -80", has been brieflyreported.lS5 A.G. S.3. THE TRANSITION ELEMENTSTHE transition elements will be considered in an order similar to thatadopted last year. Those aspects which are not necessarily characteristicof any single transition metal but which illustrate the general properties ofcomplexes or ligands are discussed first under the heading '' complexes."Organometallic compounds which contain a B metal-carbon bond are dis-177 H. Schmidt and H.Meinert, Angew. Chem., 1959, 71, 126.178 R. A. Zingaro and W. E. Tolberg, J . Amer. Chem. SOC., 1959, 81, 1353.179 T. M, Connor and M. C. R. Symons. J., 1959, 963.180 W. B. Person, R. E. Humphrey, and A. I. Popov, J . Amer. Chem. SOC., 1969,181 J. G. Traynham and J. R. Olechowski, J . Amer. Chem. SOL, 1959, 81, 571.182 H.-A. Lehmann and H. Hesselbarth, 2. anorg. Chem., 1959, 299, 51.*83 E. E. Aynsley and S. Sampath, J., 1959, 3099.I84 Z. Hauptman, Coll. Czech. Chem. Comm., 1959, 24, 2132.185 M. Schmeisser and E. Scharf, dngew. Chcm., 1959, 71, 524.81, 273SHARP f THE TIL4NSITION ELEMENTS. 131cussed next, and the chemistry of the elements is considered systematicallyin the ten transition groups.Complexes.-(a) General.The most important publication in this fieldhas been that of the Fai-aday Society Discussion on “ Ions of the TransitionElements ” which contains general surveys on ligand-field and molecular-orbital theories as applied to metal ions and includes many papers ondetailed applications of these theories to chemical and spectroscopic, mag-netic, and other physical phen0mena.l The proceedings of the InternationalConference 02 Co-ordination Chemistry, held in London in April, 1959, havebeen published as a Chemical Society Special Publication.2 The effect ofinner-orbital splitting on the thermodynamic properties of transition-metalcompounds has been re~iewed.~Radiochemical studies have shown differences in bond energies in thehalogenoplatinate series.The average Pt-Cl bond is12 kcal. stronger than the Pt-I bond and the averagePt-Br bond is 4-5 kcal. stronger than the Pt-I bond.6Cl- lies far to the right because of entropy andsolvation factors, but it is suggested that even incomplexes where the iodide is more stable than thechloride the Rl-C1 bond strength is, in fact, greater than the M-I band~trength.~ Co-ordination of an organic molecule as a ligand makes themolecule much more reactive. The reaction of nickel and palladiumacetylacetonates with nitrite ion gives complexes which probably havestructure (1). Potassium nitropalladite reacts with acetylacetone to givea 5-co-ordinate nitrosyl complex, and a similar cobalt complex is formedfrom cobalt(r1) acetylacetonate andnitric oxide.Copper( 11) acetyl-acetonate gives a 3-nitroacetylacetone /+ complex when treated with dinitrogentetroxide .5 Dihydroxymanganese ( IV)phthalocyanine and aquohydroxy-chromium(II1) phthalocyanine aret3) true 6-co-ordinate complexes and are /?/ = Mn phthalocyanine dibasic acids. It is considered thatthe anions are stabilised by con-jugation between the mutually perpendicular phthalocyanine and oxy-groups,such perpendicular conjugation being a new phenomenon in co-ordinationchemistry.6 Manganese(I1) phthalocyanine combines reversibly with oxygenwhen dissolved in pyridine; the product contains MnIV doubly bonded tooxygen (2) and is converted into a polymer (3) on heating.’ It was shown in1 Discuss. Faraduy SOC., 1958, 26.2 ‘ International Conference on Co-ordination Chemistry, ” Special Publication No.13, The Chemical Society, London, 1959.3 P. George and D.S. McClure, “ Progress in Inorganic Chemistry,” 1959, 1, 381.4 A. J. Po& and M. S. Vaidya, Nature, 1959, 184, 1139.5 C. Djordjevic, J. Lewis, and R. S. Nyholm, Chem. avtd Id., 1959, 122; R. Nast6 J. A. Elvidge and A. B. P. Lever, Proc. Chem. Soc., 1959, 123.7 J. A. Elvidge and A. B. P. Lever, Proc. Chem. SOL, 1959, 195.OHMeC=N, ,N=CAcHO/~ ~ ~ = ~ 0 1 M ;N=&.+ The overall equilibrium PtCls2- -1 61- --+ PtIG2- +(1)1 [& 0,&7 (2)and H. Bier, Ber., 1959, 92, 1858132 INORGANIC CHEMISTRY.1900 that silver ions produce colour changes with thiocyanato-complexes andthis observation has now been extended to a study of the interaction of silver(1)and mercury(11) ions with cis- and trans-[M1ll(NCS)ZRp]+ ions (MIII = Coor Cr, R = amine).Stable salts were not isolated, but evidence was foundfor the existence of several new species in solution and it is considered thatthe original complexes had an isothiocyanato-structure, the new complexeshaving in addition Ag-S or Hg-S bondss Structural studies have beenmade on Ni(H,O)H,Y, NH,CoY,2H20, and RbCoY,2H20 (Y4- = ethylene-diamine-NNN'N'-tetra-acetate ion). In the cobalt salts the ethylene-diaminetetra-acetate ion is acting as a hexadentate ligand but the H,Y2-ion is only acting as a quinquedentate ligand in the nickel salt, there beingone water molecule co-ordinated to the metal and one free CH2*C02H arm.9The thermodynamics of formation of ethylenediaminetetra-acetic acidcomplexes has been discussed by Staveley and Randall and changes inco-ordination number have been related to crystal-field effects.1°Details have been published of a method of determining magnetic sus-ceptibility by measuring shifts in the proton resonance lines of inert referencemolecules; less than 0.03 ml.of a dilute solution can be studied.ll Themagnetic susceptibilities of tetra- and hexa-co-ordinate cobalt (11) complexesand of copper(I1) complexes have been investigated in detail. The magneticmoments of the copper compounds are correlated on the basis of an octa-hedral or distorted octahedral (in the extreme case planar) configurationabout the copper.12 Numerous infrared studies on complexes have beenreported during the year.The transmission of electronic effects through ametal atom has been investigated by examining the effect of different ligandson the metal-hydrogen vibrations in hydrides and on N-H vibrations inammines. The changes seem to be mainly inductive in origin, but mesomericeffects and interaction between N-hydrogen atoms and the d orbitals of themetal are also important .13 The infrared spectra of compounds containingM=O groups (M = any transition metal) have a band between 900 and1100 cm.-lJ4 The infrared spectra of ethylenediamine complexes arebelieved to permit differentiation between those complexes in which theligand has cis- and those in which it has trans-c~nfigurations.~~ The infraredspectra of cobalt@), platinum(@, and palladium(11) ammines have alsobeen studied.l6 Complex fluorides show infrared absorption in the potassium8 W.C. Waggener, J. A. Mattern, and G. H. Cartledge, J . Amer. Chem. SOL, 1959,9 H. A. Weddiem and J. L. Hoard, J . Arnev. Chew. Soc., 1969, 81, 549; G. S. Smith10 L. A. K. Staveley and T. Randall, Discuss. Faraday Soc., 1958, 26, 157.11 D. F. Evans, J., 1959, 2003.12 B. N. Figgis and R. S. Nyholm, J., 1959, 338; B. N. Figgis and C. M. Harris,13 J. Chatt, L. A. Duncanson, B. L. Shaw, and L. M. Venanzi, Discuss. Faraday14 C. G. Barraclough, 3 . Lewis, and R. S. Nyholm, J., 1959, 3552.15 D. B. Powell and N. Sheppard, J., 1959, 791, 3089; see also K.Brodersen, 2.anorg. Chem., 1959, 298, 142.16 H. Siebert, 2. anorg. Chem., 1959, 298, 51; S. Mizushima, I. Nakagawa, M. J.Schmelz, C. Curran, and J. V. Quagliano, Spectrochim. Acta, 1958, 13, 31; H. Block,Trans. Faraday SOL, 1959, 55, 867.81, 2958.and J. L. Hoard, ibid., p. 556.J., 1959, 855.SOL, 1958, 26, 131SHARP: THE TRANSITION ELEMENTS. 133bromide or sodium chloride region and it is concluded that there is somecovalent bonding even in perovskites, KMF,.17Stereospecific influences in metal complexes containing optically activeligands have received considerable attention. Formation constants for thecomplexes formed from L- or racemic asparagine and cupric ions show thatthe formation of the non-mixed complex is favoured as compared with theformation of the mixed.ls The isolation of non-mixed complexes has beendemonstrated in several other experiments. Oxidation of a cobalt (11) saltin the presence of L-propylenediamine (pren) gives the pure D-ZZZ and L-111isomers; the base can be recovered from the complex optically pure.lgcis- or trans-[Co(en),Cl,]Cl (en = ethylenediamine) reacts with L-propylene-diamine to give C~(en),~+ and Co(~-pren),~+ ions with no mixed complexes:in this case a seven- or eight-co-ordinate cobalt(rr1) species is suggested asan intermediate.,O A demonstration that some of the optical isomers areless stable than others has also been given for cis-dinitro(ethy1enediamine)-(butane-2,3-diamine)cobalt (1rr)ions and a detailed study of the relativestability and reactivity has been given in terms of the stereochemistry of theindividual chelate rings.21 In platinum complexes, chloroplatinic acidreacts with D-propylenediamine to give a predominant yield of the L-dddand D-ddd isomers of the Pt(~-pren),~+ ion 22 but rather surprisingly thereaction of Pt(L-pren)CI, with ethylenediamine or of Pt(en)Clp with L-propylenediamine in dimet hylformamide gives a series of mixed complexeswhich are stable in aqueous solution.23Much has beenpublished on the kinetics of inorganic reactions and space permits onlythe briefest review of this field. Taube has written two reviews on thesubject 24 and there has been a report of a symposium on inorganic reactionmechanisms in which several aspects of the subject are reviewed and dis-cussed.25 Russian work on the kinetics of substitution in palladium andplatinum salts has also been summarised.26By making the assumption that relaxation occurs almost entirely in thefirst co-ordination sphere of cations, study of the 170 magnetic resonancespectrum of solutions of paramagnetic ions can give lower limits for the rateof exchange of bulk water molecules with those in the first co-ordinationsphere of the cations.Values found range from less than lo-' sec. forMn2+ to less than lo4 sec. for Ni2+. C P ions exchange water by a differentmechanism.27 The reaction between a quaternary ammonium chloride and(b) Mechanisms of reactions of inorganic complexes.17 R. D. Peacock and D. W.A. Sharp, J., 1959, 2762.18 W. E. Bennett, J . Amer. Chem. Soc., 1959, 81, 246.19 F. P. Dwyer, F. L. Garvan, and A. Shulman, J . Amer. Chem. SOC., 1959, $1, 290.20 F. P. Dwyer and A. M. Sargeson, J . Amer. Chem. SOC., 1959, 81, 5269.21 E. J. Corey and J. C. Bailar, jun,, J . Amer. Chem. SOC., 1959, 81, 2620; W. E.22 F. P. Dwyer and F. L. Garvan, J . Amer. Chem. SOL, 1959, 81, 1043.23 F. P. Dwyer and A. M. Sargeson, J . Amer. Chem. Soc., 1959, 81, 5272,24 H. Taube, Adv. Inorg. Chem. Radiochewt., 1969, 1, 1; also ref. 2, p. 57.2G J. Phys. Chem., 1959, 63, 321 et seq.26 A. A. Grinberg, Zhur. neorg. Khim., 1959, 4, 1517 [683].*37 R. E. Connick and R. E. Poulson, J. Chem. Phys., 1959, 30, 759; see also R. A.Bernheim, T. H. Brown, H. S. Gutowsky, and D.E. Woessner, ibid., p. 950.Cooley, Chui Fan Liu, and J. C. Bailar, jun., ibid., p. 4189.* Figures in brackets refer to the English translation134 INORGANIC CHEMISTRY.biscyclopentadienyltitanium(1v) bromide to give the corresponding chloridetakes place by a displacement (&2) process in tetrahydrofuran and benzene.The corresponding reaction with lithium chloride in tetrahydrofuran appearsto involve a nucleophilic displacement by the solvent.28 Contrary toprevious reports, the mechanism of electron exchange between uranium-@)and -(vI) species depends markedly upon the solvent.29 The reaction be-tween plutonium(1v) and uranium(1v) is very similar to the plutonium(1v)disproportionation and the Ce(Iv)-U(Iv) reactions and involves the form-ation of an intermediate deprotonated H2O-Pu(~v)-U(rv) complex, possibly[PU*O*U]~+.~~ Change of solvent from water to deuterium oxide decreasesthe rate of reaction of Cr2+ with (NH,),CO(OI--I,)~+ and (NH,),CO(OH)~'.The second reaction prcceeds by oxygen transfer and it is inferred that theformer proceeds by a similar mechanism; the decrease in rate is taken toindicate that the O-H bonds are stretched in the activated complex.31 Fromthe increase in rate of racemisation of (bipyridyl),Fe2+ and (o-phen-anthroline),Fe2+ ions with increase in the methanol content of the methanol-water solvent it is inferred that in alcohol-rich solution the racemisationtakes place by an intramolecular process.32 The racemisation of the[C0(en)~]3+ ion under forcing conditions proceeds by an SN2 mechanism:[C~(en)~],+ + en =+= primary intermediate.Hydroxide ion attacks the[Co(en),13+ ion at 85" to give [CO(~~),(OH)(H,O)]~+ but the hydroxide iondoes not play a key part in the overall racemisation process. The catalyticracemisation of this ion in the presence of charcoal, platinum, or silica geloccurs, with partial decomposition, through an activated six-co-ordinateintermediate; the [Rh(en),I3+ ion is not racemised under these conditions.%Electron exchange between cobaltous [containing species Co(NH3),,2+ andCo(NH,),,OH+ (n up to 6 or 5)] and cobaltic ammines proceeds through asymmetrical hydroxy-bridged complex.34 The oxidation of Cr2+ with[(NH,),Co(fumarate)]+ or its half ester proceeds through a bridge to thecarboxy-group of the acid.Electron transfer, which is accompanied byhydrolysis of the ester, takes place through the conjugated system of theester.35 Study of the rate of base-catalysed deuterium loss from deuterated[Co(NH3)J3+ and [Co(C,O,)(NH,),]+ ions has shown that these ions are acidsby virtue of their association and reaction with hydroxyl ions-not by theirability to act as proton donors.36 Isotopic exchange of chloride ion in the[NH,PtCl,]- ion shows that cis- and frans-chlorines in the complex are in-distinguishable; this result does not disprove the existence of a strong trans-effect since there may be internal rearrangements in the intermediate species.It is suggested that an Sx2 reaction in which Y replaces X, which is trans28 A.Jensen and F. Basolo, J . Amer. Chem. SOL, 1959, 81, 3813.D. M. Mathews, J. D. Hefley, and E. S. Amis, J . Phys. Chem., 1959, 63, 1236.30 T. W. Newton, J . Phys. Chem., 1959, 63, 1493.31 A. Zwickel and H. Taube, J . Amer. Chem. Soc., 1959, 81, 1288.32 L. Seiden, F. Basolo, and H. M. Neumann, J . Amer. Chem. SOC., 1959, 81, 3809.33 W. G. Gehmann and W. C. Fernelius, J . Inorg. Nuclear Chem., 1959, 9, 71;** E. Appelman, M. Anbar, and H. Taube, J . Phys. Chew., 1959, 63, 126.35 R. T. M. Fraser, D. K. Sebera, and H. Taube, J . Amer. Chem. SOC., 1959, 81,36 H. Block and V. Gold, J., 1959, 966.D. Sen and W. C. Fernelius, ibid., 1959, 10, 269.2906SHARP: THE TRANSITION ELEMENTS. 135to L, takes place as shown with a transition state which is symmetrical forboth the entering and the leaving group-a transition state which has beenutilised to account for the trans-effe~t.~'S: A i/ L-qt-x/ i5 A *4s: A i /L - P t - Y(c) CarbonyZs.Some theoretical aspects of metal carbonyls and of theproducts resulting froin the reactions between them and acetylenes havebeen considered during the year by Orgel,% and the use of metal carbonylsas catalytic intermediates in organic chemistry has also been reviewed.39An important new preparation for carbonyls has been reported. Sodiumbenzophenone ketyl reacts with chromic chloride in tetrahydrofuran to givean intermediate, probably chromium benzophenone ketyl, which reactsfurther with carbon monoxide under pressure at 100" to give chromiumhexacarbonyl in good yield.Manganese carbonyl was prepared similarly.@Molybdenum and tungsten carbonyls have been prepared by metatheticalexchange between iron pentacarbonyl and molybdenum pentachloride ortungsten he~achloride.~~ The trigonal bipyramidal nature of iron penta-carbonyl seems to be completely established by its Raman spectrum; 42 aresult confirmed by a comparison of the directly measured entropy with thatcalculated from spectroscopic data.43 However, the structure of cobaltcarbonyl is still unknown. By analogy with the structure of the complexCo,(CO),,HCiCH, a non-coplanar structure (4) has been proposed forCO,(CO),.~ This is in agreement with the infrared spectrumG and fits inwith the tendency for Co,(CO), to take up an extra carbonyl group under37 T.S. Elleman, J. W. Reishus, and D. S. Martin, jun., J . Amer. Chem. Soc., 1959,38 L. E. Orgel, ref. 2, p. 93.39 H. W. Sternberg and I. Wender, ref. 2, p. 35.40 R. D. Closson, L. R. Buzbee, and G. G. Ecke, J . Amer. Chem. Soc., 1958,80, 6167.4 1 A. N. Nesmeyanov, I<. N. Anisimov, E. P. Mikheev, V. L. Volkov, and 2. P.Valueva, Zlzur. neorg. Khim.. 1959, 4, 249 [107]; A. N. Nesmeyanov, E. P. Mikheev,I<. N. Anisimov, V. L. Volkov, and 2. P. Valueva, ibid., p. 503 [228].42 H. Stammreich, 0. Sala, and Y . Tavares, ./. Chem. Phys., 1959, 30, 856.43 A. J. Leadbetter and J. E. Spice, Canad. J . Chem., 1959, 37, 1923.44 0. S. Mills and G. Robinson, Proc. Chem. Soc., 1959, 156.45 G. Ror and I,. Mark6, Spertrorhim. Acta, 1959, 747.81, 10136 INORGANIC CHEMISTRY.pressure, the bonding of the extra group being to the vacant trigonal bridgingposition.It is possible, however, that when this extra carbon monoxidegroup is taken up the reaction CO + Co,(CO), + [Co(CO),]+ + [Co(CO),]-takes place.46Molybdenum and tungsten carbonyls react with sodium in liquidammonia to give Na,[M-II (CO),]; hydrolysis of the anion gives the species[Mo-I,(CO),H]-. Reduction of chromium carbonyl with sodium boro-hydride gives Na,[Cr-12(CO),,] which reacts with amines to give substitutedcarbonyls and carbonyl anions and can be reduced with sodium toNa,[Cr-II(CO),] .47 The broad-line proton magnetic resonance spectrum ofiron carbonyl hydride, Fe(CO),H,, gives an H-H distance of 1-88 & 0.05with an H-Fe-H angle of 109" to 125".The Fe-H distance is of the sameorder as the atomic radius of iron but the exact configuration of the moleculeis unknown.48 Dicarbonylcyclopentadienyliron chloride is reduced bysodium borohydride to dicarbonylcyclopentadienyliron hydride, an unstablecompound, m. p. -5", characterised by its nuclear magnetic resonancespectrum.49 Rhenium carbonyl reacts with alkali metals in tetrahydrofuranto give MRe(CO), derivatives (M = Li and Na). These are hydrolysed torhenium carbonyl hydride by phosphoric acid.60 Chromium, molybdenum,and tungsten hexacarbonyls react with hydroxide ions to give polynuclearanions which probably contain hydroxyl bridges ; hydride species areproduced from these anions by acids, substituted carbonyls by bases.51Biscyclopentadienyltitanium dicarbonyl, (C,H,),Ti(CO),, the first car-bony1 derivative of titanium, has been prepared by the action of carbonmonoxide and sodium cyclopentadienylide on biscyclopentadienyltitaniumdichloride. The compound forms reddish-brown, air-sensitive crystals.52Substituted chromium-group carbonyls have been prepared by reaction ofamines with alkali pentacarbonylchromates(- 11) ,= by reaction of triaryl andtriaryloxy-derivatives of Group V with the carbonyls,5q and by replacingthe arene group in arenechromium tricarbonyls or the cycloheptatrienegroup in C,H,MO(CO),.~~ These derivatives contain five, four, or threecarbonyl groups per molecule. Chromium and molybdenum carbonylsreact with 1 -met h ylp yridinium iodide to give iodopen t acarbonyl- 1 -methyl-pyridinium metallates(-I), (pyMe) [IM(CO),], which on gentle heating areconverted in to x- 1 -me thylpyridinium-me tal tricarbonyl~.~6 Thermal de-48 S.Metlin, I. Wender, and H. w. Sternberg, Nature, 1959, 183, 457.47 H. Behrens and J. Kohler, 2. Nutuvforsch., 1959, 14b, 463; H. Behrens and48 E. 0. Bishop, J. L. Down, P. R. Emtage, R. E. Richards, and G. Wilkinson, J.,49 M. L. H. Green, C. N. Street, and G. Wilkinson, 2. Naturforsch., 1959, 14b, 738.50 W. Hieber and G. Braun, 2. Naturforsch., 1959, 14b, 132.5 1 W. Hieber and K. Rieger, 2. unorg. Chem., 1959,300, 288; W. Hieber, K. Englert,62 J. G. Murray, J . Amer. Chem. SOC., 1959, 81, 752.58 H. Behrens and J. Kohler, 2. Nafuvforsch., 1959, 14b, 463.64 W.Hieber and J. Peterhans, 2. Nuturfovsch., 1959, 14b, 462; C. N. Matthews,T. A. Magee. and J. H. Wotiz, J . Amer. Chem. SOC., 1959, 81, 2273; A. Luttringhausand W. Kullick, Tetrdzedron Letters, 1959, No. 10, 13.66 E. W. Abel, M. A. Bennett, and G. Wilkinson, J., 1959, 2323.66 E. 0. Fischer and K. Ofele, 2. Nuturfursch., 1989, 14b, 736; see also B. MooreW . Haag, ibid., p . 600.1959, 2484.and K . Rieger, ibid., p p . 295, 304; W. Hieber and K . Englert, ibid., p. 311.and G. Wilkinson, Proc. Chem. SOC., 1969, 61SHARP: THE TRANSITION ELEMENTS. 137composition of manganese carbonyl halides gives bridged [Mn (CO),X],dimer~.~’ Many manganese carbonyls and manganese carbonyl halidessubstituted with Group V and VI ligands have been prepared by directinteraction between the ligand and the carbonyl, a carbonyl halide, or anarenemanganese carb0nyl.~5, 57-69 The substance resulting from theinteraction of triphenylphosphine and rhenium carbonyl chloride, previouslyregarded as [(Ph,P),Re(CO),] +C1-, is now considered from infrared andmolecular-weight evidence to be (Ph,P),Re(CO),Cl.Similar productsresult from the reaction between other Group V ligands and manganese andrhenium tetra- or penta-csrbonyl halides.57Iron carbonyls react with pyridines, pyridine N-oxides, and dimethylsulphoxides to give derivatives with anionic iron carbonyl species ; thecations consist of hexa-co-ordinated ferrous ions.60 Di(tertiary arsine)ironcarbonyls and carbonyl halides of the types Fe(CO),D, Fe(CO)D,,Fe(CO)DX, and Fe(CO),DX, (D = o-phenylenebisdimethylarsine, X = Bror I) have been prepared by interaction of iron pentacarbonyl and thearsine followed by oxidation of the products with iodine or bromine.61 The[Fe(C0),]2- anion reacts with oxides and other derivatives of arsenic,antimony, bismuth, tin, lead, and thallium to give complex non-ionic deriv-atives in which it is considered that iron tetracarbonyl groups are con-densed through the metals or metalloids.62(d) Cyanides and isocyanides.Little work on pure cyanides has beenreported this year and most aspects will be considered under the headingof the other ligands involved. Reduction of potassium cobalticyanidewith potassium in liquid ammonia gives pale yellow, very reactiveK,COI(CN),.~~ Further details have now been published of the high-resolution nuclear magnetic resonance studies on ions found in solutionscontaining cobalt (11) cyanide complexes.63a It is now considered that themain species present is [HCo1(CN),I3-; a similar ion, [HRh1(CN),I3-, isformed when rhodicyanide ions are reduced with sodium b~rohydride.~~From infrared studies it appears probable that the [COI(CN),(CO)]~- ion isplanar whilst the [CO~~(CN)~]~- ion has a symmetrical structure with ametal-metal bond 64 similar to that proposed for the [Ni2(CN),(CO)~4- ion.aThe isocyanide complexes of the transition metals have been reviewedduring the year.66 Isocyanide complexes of cobalt(x1) are formed in aqueoussolution ; reduction gives cobalt (I) complexes.The cobalt (11) complexesexist in two forms, red diamagnetic and blue paramagneti~.~~57 E. W. Abel and G. Wilkinson, J., 1959, 1501.58 W. Hieber and W. Freyer, Ber., 1959,92, 1765; W. Hieber and W. Schropp, jun.,59 R. S. Nyholm and D. V. R. Rao, Proc. Chem. Soc., 1959, 130.80 W. Hieber and A. Lipp, Ber., 1959, 92, 2075, 2085.61 H. Nigam, R. S. Nyholm, and D. V. R. Rao, J., 1959, 1397.62 W. Hieber, J. Gruber, and F. Lux, 2. anorg. Chew., 1959, 800, 275.63 G. W. Watt and R. J. Thompson, J . Inorg. Nuclear Chem., 1959, 9, 311.ma See Ann. Reports, 1958, 55, 148.64 W. P. Griffith and G. Wilkinson, J., 1959, 2757.66 W. P. Griffith, F. A. Cotton, and G. Wilkinson, J . Inorg. NucEear Chew., 1959, 10,66 L. Malatesta, ‘ I Progress in Inorganic Chemistry,” 1959, Vol.I, 283.2. Naturforsch., 1959, 14b, 460.23.A. Sacco and M. Freni, Gazzetta, 1959, 89, 1800138 INORGANIC CHEMISTRY.(e) Nztrosyls. Orange, deliquescent K5[V-1(CN)5(NO)],H,0 is preparedby reducing potassium vanadate in the presence of excess of base and ofcyanide with hydroxylamine hydroch1oride.a The anion is a member of theisoelec tronic series [V-I (CN), ( N0)l5-, [MnI (CN) (N 0)13-, [FeII( CN), (NO)] ,-.The CrO complex could not be isolated but green K3[Cr1(CN)5(NO)]was obtained under similar conditions. On the basis of chemical, spectro-scopic, and magnetic susceptibility data the previously reportedK,[MoO(CN),(NO)] ,2H20 is reformulated as K,[MO*~(OH),(CN>,(NO)] anda h ydroxy-cyanide previously reported as K, [MorV(OH),( CN), ( H,0)] ,2H,Oas K3[MoV(OH),(CN)4],2H,0 or K,[Mo~~~O~(CN),(H,O)],~H,O.In theselatter complexes molybdenum seems to attain its preferred co-ordinationnumber of eight.69 Oxidation of the [Mn*(CN),(NO)]3- anion with nitricacid gives the yellow [M~III(CN)~(NO)]~- anion.70 h complete structuraldetermination on [Ru(NH,),(NO) (OH)]Cl, has been described. Theruthenium atom is octahedrally co-ordinated with the hydroxyl and nitrosylgroups in trans-positions; the Ru-N-0 angle is 150°, and this complex mustbe compared with cobalt nitrosyl dithiocarbamate in which the Co-N-Osystem is also non-linear.'l Physicochemical studies have been made onthe nickel nitrosyl hydroxides which are prepared by the action of nitricoxide on nickel carbonyl in the presence of water and an alcohol.Thecomplexes, which have the general formula Ni(N0) (OR),(OH),-,, are con-sidered to contain dipositive nickel in tetrahedral co-ordination. These deepblue compounds slowly change to green nitro-complexes which areprobably polymeric, with octahedral co-ordination about the metal, e.g.,Ni(N0) (OH) (OMe), - Ni(N0,) (OMe) (MeOH). The iron complexes corre-sponding to the nickel nitrosyl hydroxideshave been reformulated (5) to contain tetra-ON% Fe do\ rr hedral iron(0). Nitrosyl halides of palladium,M&HN l o f F e k NO Pd(NO),C12, and rhodium, Rh(NO),Cl, have(') been reformulated to contain PdO and Rh(-I), thelatter compound being almost certainly polymeric. K [Co(-I>(CN) (NO) (CO),]is considered to have tetrahedral co-ordination about the cobalt, the nitrosylgroup donating as NO+.',Perfluoro-olefins such as tetrafluoroethylene andperfluorocyclohexadiene react with iron pentacarbonyl to give the complexes(C,F,),Fe(CO), and C,F,Fe(CO),.A complex analogous to Zeise's salt isformed in solution in aqueous ethanol from tetrafluoroethylene and sodiumchloroplatinite, but the solid complex could not be isolated. These are thefirst perfluoro-olefin-transition metal complexes and provide interestinggrounds for discussion of the effect of the electronegative fluorine on thestability of olefin complexes.73 Acrylonitrile, with an activated doubleHOMeMe(f ) OZe@ complexes.68 W. P. Griffith, J. Lewis, and G. Wilkinson, J., 1959, 1632.69 W.P. Griffith, J. Lewis, and G. Wilkinson, J., 1959, 872.70 F. A. Cotton, R. R. Monchamp, R. J. M. Henry, and R. C . Young, J . Inovg.71 G. B. Bokii and N. A. Paipiev, KrystaZlografya, 1958, 2, 691 ; cf. P. R. H. Alder-a W. P. Griffith, J. Lewis, and G. Wjlkinson, J. 1959, 1776.73 K. F. Watterson and G. Wilkinson, Chem. and Tnd., 1,959, 991.Nuclear Chem.. 1959, 10, 28.man and P. G. Owston, Nature, 1956, 178, 1071SHARP : THE TR.4NSITION ELEMENTS. 1.39bond, reacts with nickel carbonyl to give a red complex (6) which does notinvolve the lone pair of electrons on the nitrogen atom as in normal nitfilecomplexes. Bisacrylonitrilenickel is a very efficient polymerisation catalyst ;it is still electron-deficient and forms an adduct with/ triphen ylphosphine. 74 Substituted st yrene-platinumCH '.l-,C . H complexes, (X~C,H,*CH:CH,,PtCl,), (x = H, 3-C1,Q-CH,*O, %NO,, 4-N02, and 4-CH3), have been pre-. . . . pared by displacement of ethylene from ethylene-platinous chloride. When dissolved in alcoholic NC hydrogen chloride the dimers react to give ions(X*C,H,~CH:CH,,PtCl,), + 2HCl- 2H+(X*C,H,CH:CH,,PtCl3)-. In theolefin complexes all substituents are stabilising relative to styrene and thisfact is consistent with the presence of a double bond between platinum andthe ligand, the o and x bonds being affected approximately equally but inopposite directions by the s u b s t i t ~ e n t . ~ ~ It is pertinent to remark, how-ever, that the nature of the bonding in olefin complexes is still unknown;the infrared spectra of platinum ethylene complexes may be interpretedvery convincingly on the basis of Pt-C Q bonds.', In the " 0x0 " reactionfor the hydroformylation of olefins, studies of the rate of absorption ofcarbon monoxide have shown that it most likely that the reaction proceedsthrough an intermediate cobalt carbonyl hydride-olefin-carbon monoxidecomplex.77. *,CH- CHIConsiderable work has been published on the metal complexes of cyclicpolyenes. Norbornadiene (7) forms complexes with A&), CU(I) , Pd(11) ,Pt(II), Rh(I), and Ru(II). The last, a polymeric bridged complex, is thefirst olefin complex of r u t h e n i ~ r n . ~ ~ Other diene complexes describedinclude : the dimethyl acetylenedicarboxylate adduct of cyclo-octatetraene(8) with Rh(1) ; the maleic anhydride adduct of cyclo-octatetraene (9) withRh( I) ; 78 cyclo-oct a- 1,5-diene-molybdenurn and -tungsten tetracarbonylsand -ruthenium dihalides ; 79 and norbornadieneiron tricarbonyl.80 Fromthis fairly wide range of complexes it seems that conjugation is not a neces-sary requisite for the formation of diene complexes-even with iron-groupelements.81 Cyclo-octa-1,3,5- and -1,3,6-trienes (L) form the following74 G.N. Schrauzer, J. Amer. Chem. SOL, 1959, 81, 5310.75 J. R. Joy and M. Orchin, J. Amer. Chem. SOC., 1959, 81, 305.7' A. A. Babushkin, L. A. Gribov, and A. D. Gel'man, Zhur. neorg. Khim., 1959, 4,7 7 L. Kirch and M. Orchin, J. Amer. Chem. SOC., 1959, 81, 3597.78 E. W. Abel, M. A.Bennett, and G. Wilkinson, J., 1959, 3178.79 T. A. Manuel and F. G. A. Stone, Chem. and Ind., 1959, 1349; E. 0. Fischer andW. Frolich, Ber., 1959, 92, 2995; M. A. Bennett and G. Wilkinson, Chem. and Ind.,1959, 1516.80 R. Burton, M. L. H. Green, E. W. Abel, and G. Wilkinson, Chem. and Ind.,1958, 1592; R. Pettit, J . Amer. Chem. SOC., 1959, 81, 1266.81 Cf. B. F. Hallam and P. L. Pauson, J., 1958, 642.1542 [695]140 INORGANIC CHEMISTRY.complexes: LM(CO), (M = Cr, Mo, and Fe), L,M(CO), (M = Mo and W),and [LCo(CO),],. It seems likely that the two isomers may give complexesof different stoicheiometry and this may be related to the stereochemistryof the x bonds in the olefins (10, ll).s2 Cyclo-octatetraene complexes withRh(1) and iron carbonyls have been prepared.Normal cyclo-octatetraeneironcarbonyl has the formula C,H,Fe(CO), but reaction with excess of iron(10)carbonyl gives another complex in which the iron tricarbonyls are bonded toopposite sides of the octatetraene (12) .78983 All the complexes mentionedabove are prepared in the simplest possible way-by shaking, refluxing, orirradiating a mixture of the olefin with the metal halide or metal carbonyl.Complete structure determinations have been carried out for two complexesof this type. In the cyclo-octatetraene dimer (13)-silver nitrate structureeach silver atom is associated with two double bondsfrom different dimer molecules.84 The silver ioninteracts with two non-adjacent x bonds of eachcyclo-octatetraene molecule in the cyclo-octa-tetraene-silver nitrate complex.In this compound(13) there appears to be some interaction between the @ silver and nitrate i0ns.~5(g) Acetylene complexes. Acetylene complexes are now becoming dividedinto two distinct types: those in which the acetylene remains as a recognis-able entity in the complex, and those in which it has polymerised or hasreacted with the other ligands present.The acetylides of the transition metals have been reviewed by Nast.86K6[Ni1,(CzCR),] (R = H, CH,, C,H,) and K,Zn(C,H), have been preparedby the action of potassium acetylides in liquid ammonia on K,[NiI,(CN),(CO)Jand Zn(SCN),,2NH3 respe~tively.~~ The action of acetylene on pentacyano-cobaltate(11) species in aqueous solution gives the yellow saltK,[Co,(CN),,,C,H,] ,4H,O, a diamagnetic complex which is given the struc-ture (14) on the basis of spectroscopic measurements.8s Platinum acetylenecomplexes have been prepared by the reaction between an acetylene and82 E.0. Fischer, C. Palm, and H. P. Fritz, Bey., 1959, 92, 2645; E. 0. Fischer andC. Palm, 2. Nuturforsch., 1959, 14b, 598.88 T. A. Manuel and F. G. A. Stone, Proc. Chem. Soc., 1959, 90; M. D. Rausch andG. N. Schrauzer, Chem. and Ind., 1959, 957; A. Nakamura and N. Hagihara, Bull.Chem. SOC. Japan, 1959, 32, 880.84 S. C. Nyburg and J. Hilton, Acta Cryst., 1959, 12, 116.85 F. S. Mathews and W. N. Lipscomb, J . Phys. Chem., 1959, 83, 845.86 R. Nast, ref. 2, p. 103.87 R. Nast and H. Kasperl, Bey., 1959, 92, 2135; R. Nast and R. Miiller, ibid., 1958,88 W.P. Griffith and G. Wilkinson, J., 1959, 1629.91, 2861SHAKP: THE TRANSITION ELEMENTS. 141chloroplatinites or K [C,H,PtClJ. Monosubstituted acetylenes give in-definite products, but complexes of the types Y [acPtCl,], ac,Pt,Cl,, andtrans-[ac(pip)PtCI,] (Y = univalent cation,6 - ac = acetylene, pip = piperidhe) have beenisolated by using disubstituted acetyleness9Hydroxyacetylenes give stable complexes withplatinum, and it appears that there is con-electrons of the hydroxyl groups and the metalatom.g0 Cyclopentadienylnickel dicarbonylreacts with acetylenes to give complexes Cp,Ni,(RC,R') which are formulated(15) with the C-C bond at right angles to the Ni-Ni bond?l This structure issuggested by analogy with that found by X-ray analysis for diphenyl-111siderable interaction between the lone pairs of0ICO-c, Io'cOcO~0iacetylenedicobalt hexacarbonyl (16) ; X is the mid-point of the acetylenelinkage, the two phenyl groups being bent away from the cobalt atoms, andthe C-C bond of the acetylene being normal to the Co-Co bond.There isapproximately sixfold co-ordination about the two cobalt atoms.92 Reactionof dicobalt hexacarbonyl acetylenes with acid gives complexes of the typeHCo,(CO) ,,RC-CH. The suggested struc-ture involves three cobalt atoms in a ringwith three carbonyl groups on each metalatom, but there is no definite evidence asto the bonding of the acetylene0 0Qc/0Complexes of this type may shortly pro-vide models for the absorption of acetyleneon metal surfaces.The complex Co,(CO),,HCiCH has0 a structure involving a lactone ring'CI which must result from addition ofcarbon monoxide to acetylene.The twocobalt atoms are bridged by a carbon atom of the ring and a bridging car-bonyl; the two metal atoms and the bridging carbons are not co-planar (17) .aThe action of acetylenes on carbonyls or on organometallic compoundsgives wide ranges of complexes, many of which have been described duringthe year. Many of the structures are based on that found for the but-2-yne100(17)89 C. B. Bukhovets and H. K. Pukhova, Zhur. neorg. Khim., 1958, 3, 1714; J. Chatt,go J. Chatt, L. A, Duncanson, and R. G. Guy, Nature, 1959, 184, 526.O 1 J. F. Tilney-Bassett and 0. S.Mills, J . Amer. Chem. SOL, 1959, 81, 4757.92 W. G. Sly, J . Amer. Chem. SOL, 1959, 81, 18.93 R. Markby, I. Wender, R. A. Friedel, F. A. Cotton, and H. W. Sternberg, J .L. A. Duncanson, and R. G. Guy, Chem. and Ind., 1959, 430.Amer. Chem. SOL, 1968, 80, 6529142 INORGANIC CHEMISTRl-.complex of iron carbonyl hydride 93a and involve transition metal-carbonbonds with the further possibility of x bonding from the heterocyclic ringsystem containing a transition element. Alternatively, the acetylenes maybe polymerised to substituted butadienes or benzenes or may react withligands to form substituted pentadieneones. Any of these aromatic orpseudo-aromatic systems may act as x-bond donors. Thetulated for many of these complexes are supported by theirstructures pos-preparation bydirect interaction of the appropriate aromatic or olefinic system with themetal carbonyl.Thus diphenylacetylene reacts with iron pentacarbonyl inultraviolet light to give, among other products, the iron tricarbonyl complexof tetraphenylcyclopentadienone (18) ; this complex can also be preparedby direct interaction of iron pentacarbonyl and tetracyc10ne.~4 It will notbe possible to give details of all the reactions involved but systems studiedare : acetylene-iron carbonyls ; 949 95 cyclopentadienones with iron carbonyls,mercury cobalt carbonyl, cobalt carbonyl, chromium hexacarbonyl , molyb-denum hexacarbonyl, and manganese carbonyl ; g4-g6 acetylenes with(OC)3Fe--------~- p h c F e ( C O ) 3 + Ph.PCI2 -+- p h c P P hPh ’* Ph ‘ Ph Ph(20) (21)cobalt carbonyl, cyclopentadienylcobaIt dicarbonyl, and manganese carbonylLydride ; 97 acetylenes with organochromium derivative~.~B Oxidation ofiron hydi ocarbonyl-acetylene complexes eliminates one iron atom as Fez+and gives complexes which appear to be cyclic acyl derivatives of iron car-bony1 hydrid? (l!l).99 The reaction of some of the complexes describedabove kiith now-metallic halides offers a preparative route to new hetero-cyclic compounds. Pentaphenylphosphole (21) is formed by reaction ofFe,(CO),(PhG,Ph~, (20) with phenylphosphorus dichloride, and a hetero-cyclic system containing silicon [C,(C,H,),Si(C,H,)~ has also been synthesisedin this way.Pel? taphenylphosphole forms complexes with iron penta-93O Ann.Reports, 1955: 55; 150.94 G. N. Schrauzer, J . Arne#. Ciccx. Sor.. 1969, 81, 5307.95 W. Hubel, E. H. Braye, A. Clams, I<. Weiss, IT. Kruerke, D. A. Brown, G. S. D.King, and C. Hoogzand, J . Inrug. N z / c k n ~ C‘he???., 1959. 9, 204; W. Hubel and E. H.Braye, ibid., 1959 10, 250; W. Hiibel and E \G’elss, Chem. and Ind., 1959, 703; J. R,Let0 and F. A. Cotton, J . Amer. Chenz. So913 E. Weiss and W. Hubel, J . Iiaorg. N.tic /dL Y Chrnz., 2959, 11, 42.97 H. W. Sternberg, J. G. Shukys, C. n. I):)Ix-, I2 Markby, R. A. Friedel, andI. Wender, J . Amer. Chem. SOC., 1959, 81, 2339.08 G. Wilke and M. Kroner, Angew. Chew., 1939 7’1, 5 i l ; see also W. Metlesicsand H. Zeiss, J . Anzer. Chem. SOC., 1959, 81, 4117.99 J. R. Case, R. Clarkson, E.R. H. Jones, and 31. C. \f7!iitiii;, PYOC. Chem. Soc.,1939 81 2970.1959, 160SHARP THE TKANSITION ELEMENTS. 143carbonyl.loO The polymerisation of benzonitrile to triphenyltriazine byiron carbonyls is probably also an example of the type of polymerisationreaction that occurs with acetylenes.lo1Complexes with aromatic systemshave been reviewed twice during the past year.lo2 With the rapid develop-ment of the study of complexes derived from the reaction between acetylenesand metal carbonyls there is necessarily much overlap between the presentsection and the previous one. Tetramethylcyclobutadienenickel dichlorideis prepared by the action of tetramethyldichlorocyclobutene on nickelcarbonyl.lo3 The action of lithium amalgam on lJ2,3,4-tetrabromocyc1o-butane gives a mercury compound which affords what appears to be a silver-cyclobutadiene complex on reaction with silver nitrate.lM These complexesprovide the first example of the cyclobutadiene aromatic system , which seemsto be greatly stabilised when acting as a x-electron donor.New dicyclopentadienylides described during the year are dicyclopenta-dienylosmium,lo5 dicyclopentadienyl beryllium ,l06 and dicyclopentadienyl-zinc; lo' all of these complexes were prepared by standard procedures.Oxidation of dicyclopentadienylosmium gives an osmium (IV) species :(h) Complexes with aromatic systems.FeC1, 12 Cp20sIr - [Cp20srGOH]PF, ; Cp,0sI1 ___.jc [C~,OS~~I]PI;,Cp = cyclopentadienylNHIPFe NHIPF,It is considered that a vanadyl sandwich compound, possibly (C,H,),VO, isformed by oxidising dicyclopentadienylvanadium.108 On the structuralside there has been a complete structure determination of ruthenocene.Ruthenocene and osmocene are not isomorphous with ferrocene but thedetailed co-ordination about the metal is ~imilar.1~~ Dicyclopentadienylderivatives of Be, Mg, Sn, and Pb have finite dipole moments and it isapparent that the bonding in these compounds is different from that in thenon-polar ferrocene-type derivatives.The structure is interpreted byFischer as involving a a bond (22),106~110 but from additional spectroscopicevidence Wilkinson prefers a sandwich structure with the rings at an angle(23) .ll1 The reaction between dicyclopentadienylmagnesium and titanium100 E.H. Braye and W. Hubel, Claem. and Ind., 1959, 1250.101 S. F. A. Kettle and L. E. Orgel, Proc. Chem. SOC., 1959, 307.102 E. 0. Fischer and H. P. Fritz, Adv. Inorg. Chem. Radiochem., 1959, I, 5 5 ; F. A.103 R. Criegee and G. Schrader, Annalen, 1959,623,l; cf. Ann. Reports, 1958,55,269.104 M. Avram, E. Marica, and C. D. Nenitzescu, Ber., 1959, 92, 1088.105 E. 0. Fischer and H. Grubert, Ber., 1959, 92, 2302.106 E. 0. Fischer and H. P. Hofmann, Ber., 1959, 92, 482.107 E. 0. Fischer, H. P. Hofmann, and A. Treiber, 2. Naturforsch., 1959, 14b, 599.l08 H. M. McConnell, W. W. Porterfield, and R. E. Robertson, J. Chem. Phys., 1959,Io9 G. L. Hardgrove and D. I-I. Templeton, Acta Cryst., 1959, 12, 28; F. Jellinek,110 E. 0. Fischer and S. Schreiner, BEV., 1959, 92, 938.111 L.D. Dave, L). F. Evans, and G. Wilkinson, J., 1059, 3684.Cotton and G. Wilkinson, " Progress in Inorganic Chemistry," 1959, Vol. I, 1.30, 442.Z . Naturforsch., 1959, 14b, 737144 INORGANIC CHEMISTRY.tetrahalides gives cyclopentadienyltitanium trihalides and dicyclopenta-dienyltitanium dihalides.1l2 Reduction of dicyclopentadienyl-molybdenumand -tungsten halides with sodium borohydride gives the correspondinghydrides. These hyrides, containing metal-hydrogen linkages, sublimein v a c ~ 0 . ~ ~ However, the action of sodium borohydride on dicyclopenta-dienyl-cobalt and -rhodium halides results in the partial reduction of oneof the cyclopentadienyl rings to give cyclopentadienyl-metal cyclopenta-dienes, C5H5MC,H6.113 The rhodium compound and the correspondingiridium complex also result from the action of a mixture of potassiumcyclopentadienylide and cyclopentadiene on rhodium or iridium trihalides.l14Dicyclopentadienenickel(0) is formed by the reaction between nickel carbonyland cyclopentadiene.The nickel atom in this compound could be in almosttetrahedral co-ordination (24).l15 The nature of this type of complex hasbeen elucidated in a series of experiments including high-resolution infraredand nuclear magnetic resonance measurements. Deuterides and methyl(24) 0 Mderivatives corresponding to the parent complex C&?&OC5H6 have beenprepared, and it has been shown that dicyclopentadienylcobalt reacts withmethyl iodide to give cyclopentadienyl-l-endo-methylcyclopentadiene-cobalt (25) : (C5H5),Coo + Me1 + x-(C,H,)(1-endo-CH,*C5H,)Cor +(C5H5)CoI.The reaction between (C,H,),Co and carbon tetrachloride 116yields 113 the l-enndo-trichloromethylcyclopentadiene derivative which canbe reduced to the l-eutdo-dichloromethylcyclopentadiene complex. Thebonding in all these complexes appears to be from a symmetrical cyclopenta-dienyl ring plus bonding from two sets of x-electrons in a cyclopentadienering. In the cyclopentadiene compounds the endo-hydrogen is responsiblefor the low C-H stretch at -1850 cm.-lJ13 Triphenylphosphonium cyclo-pentadienylide (26) forms complexes with Group VI hexacarbonyls in whichthere is x bonding from the cyclopentadienyl ring.l17A partial structure determination on benzenechromium tricarbonyl hasshown that the benzene is symmetrically placed with respect to the chromiumatom and that the Cr-C-0 groups are linear.ll* This is in agreement withdipole-moment and microwave measurement^.^^**^^^ Reaction of the112 C.L, Sloan and W. A. Barber, J. Amer. Chem. Soc., 1959, 81, 1364.I14 E. 0. Fischer and U. Zahn, Ber., 1959, 92, 1624.1l6 S. Katz, J. F. Weiher, and A. F. Voigt, J. Amer. Chem. Soc., 1958, 80, 6459.11' E. W. Abel, Apar Singh, and G. Wilkinson, Chem. and I n d . , 1959, 1067.118 P. Corradini and G. Allegra, J. Amer. Chem. SOC., 1959, 81, 2271.1lP E. W. Randall and L. E. Sutton, Proc. Chem. SOC., 1959, 93; J. K. Tyler, A. P.M. L. €3. Green, L. Pratt, and G. Wilkinson, J., 1959, 3753.E. 0. Fischer and H.Werner, Ber., 1959, 92, 1423.Cox, and J. Sheridan, Nutwe, 1969,183, 1182SHARP : THE TRANSITION ELEMENTS. 145cobalt carbonyl-aluminium bromide complex or of a mixture of mercurycobalt carbonyl and aluminium chloride with aromatic hydrocarbons givesa trinuclear cobalt-carbon monoxide-arene cation, [Co,(Arene),(CO),] + or[Co,(Arene),(CO),]+ lZo This could be similar to the trinuclear nickel com-plex described last year.lZ0” Many complexes between silver perchlorateand polycyclic hydrocarbons such as chrysene and fluorene have beendescribed. 121The interaction of cyclopentadienylvanadium tetracarbonyl and cyclo-heptatriene gives x-cyclopentadienyl-x-cycloheptatrienylvanadium as purplecrystals. This is only the second preparation of a tropylium sandwichcompound.122 Tropyliumtricarbonylchromium(0) perchlorate (as 27) reactswith anions to give cycloheptatriene complexes (28).The cyclopenta-dienylide ion reacts with a simultaneous ring contraction and expansion togive arenechromium tri~arbony1s.l~~Organometallic Compounds of the Transition Elements.-There has been arapid growth of interest in the organometallic derivatives of the transitionelements. Many have already been mentioned under the general headingof complexes, but the present section deals with compounds containingmetal-carbon o-bonds. In general, the well-known organometallic deriv-atives of zinc, cadmium, and mercury have been excluded.Titanium halides react with methyl-lithium or methylmagnesium iodidein ether to give trimethyltitanium; a t low temperatures titanium tetra-chloride gives the tetramethyl derivative.Manganese iodide reacts in thesame way to give dimethylmanganese and diphenylmanganese and there isstrong evidence for the formation of di- and tri-methylchromium in similarreactions. Te t rame th ylt it anium reacts with titanium tetrachloride to givemethyltitanium trichloride, and methyl- and phenyl-manganese iodides areprepared similarly. Dimethylmanganese gives LiMnMe, on reaction withmethyl-lithium.124 Alkyltitanium halides are also formed in the reactionbetween titanium tetrachloride and lead tetra-alk~1s.l~~ Phenyl derivativesof chromium, molybdenum, and tungsten are obtained as phenyl-lithium-ether adducts by interaction of phenyl-lithium and the appropriate metal120 E. 0.Fischer and 0. Beckert, Awgew. Chern., 1958, 70, 744; P. Chini and R.121 G. Peyronel, I. M. Vezzosi, and S. Buffagni, Gazzetta, 1959, 89, 1863, 1869.122 R. B. King and F. G. A. Stone, J . Amer. Chem. Soc., 1959, 81, 5263.123 J. D. Munro and P. L. Pauson, Proc. Chem. Soc., 1959, 267.124 C. Beermann and K. Clauss, Angew. Chem., 1959, 71, 627; see also C. Beermann126 C. E. H. Bawn and J. Gladstone, Proc. Chem. Soc., 1959, 227.Ercoli, Gazzetla, 1958,88, 1170.Ann. Reports, 1958, 65, 152.and H. Bestian, ibid., p. 618146 INORGANIC CHEMISTRY.halides.126aryl hydrides : 127Reduction of the chromium compound gives a series of complexLi3CrPh,,2GEt,0 + Li,CrHPh5,3Et,0 ---t Li,CrH,Ph,,3Et20 .or Li3CrH,Ph,,3Et,O -+ Li,Cr,H,Ph6,3Et,0An organochromium cation is formed by the reduction of chloroforni bychromous chloride :CHCI, + 2Cr2+ + 10H,O --c, Cr(H,0),CHC1,2+ + Cr(H20)&l2+It is suggested that the reaction proceeds through CHCI, radicals.12s trans-[C,H,(PPh,)2],RuC1, reacts with aluminium alkyls to give halogenometalalkyls of the type [C2H,(PPh,),I2RuRC1 (R = Me, Et, Prn).Theseare converted into alkyl hydrides by lithium aluminium h ~ d r i d e . l ~ ~Reaction of the nickel and cobalt complexes, trans-R,MX, (R = alkyl- oraryl-phosphine, X = CI, Br), with Grignard reagents, aryl-lithiums, orsodium acetylides (in liquid ammonia) gives aryl or acetylide derivatives ofnickel or cobalt. The aryl derivatives are much more stable when the ringis ortho-substituted ; ethynyl derivatives of cobaltMe ,R are not ~ t a b 1 e .l ~ ~ Similar alkyl- or aryl-platinum(r1)derivatives were prepared (R = phosphine or 4 Pt’disulphide) in both the cis- and the tratzs-forms. Theaddition of methyliodide to trans-[(PR,),PtIIMeI]M~ gives [(PR,),PtIVMe,I,] .131 The compounds formedby the interaction of trimethylplatinum and p-(29) R‘ kc -o‘Ae’Me diketones have the structure (29) ; the platinumatom is bound directly to an active methyIenegroup.132 Many substituted platinum trimethyls [R,PtMe,]X (R = pyr-idine, amines, thiourea, X = halogen) have been prepared; the platinum-carbon bond is extremely stable.l=The Scandium Group and Lanthanides.-Scandium hydroxide gives truesolutions in concentrated sodium hydroxide and Na,[Sc(OH),] ,2H,O crystall-ises out. This hydroxy-complex is hydrolysed at sodium hydroxide con-centrations less than SM; the lithium salt is not ~ t a b 1 e .l ~ ~ Heating togetherthe appropriate oxides at high temperatures gives the compounds LiScO,,NaScO,, and LiYO,; these also are rapidly hydrolysed by water.l35 Somenew borides, MB, (M = Y, Nd, Tb, Dy, Ho, Lu) and MB, (M = Nd, Tb,Er, Lu), have been prepared but unfortunately there is not very good agree-126 F. Hein and R. Weiss, 2. anorg. Chem., 1958, 295, 145; H. Funk and \V. Hauke,127 F. Hein and R. Weiss, Naturwiss., 1959, M, 321.128 F. ,4. L. Anet, Canad. J . Chem., 1959, 37, 58; see also F. X. L. Anet and E.129 J. Chatt and R. G. Hayter, PYOC. Chem. SOC., 1959, 153.130 J.Chatt and B. L. Shaw, Chem. and ImL, 1959, 675.131 J. Chatt and B. L. Shaw, J., 1959, 705.132 A. C. Hazell, A. G. Swallow, and M. R. Truter, Chein. and Ind., 1959, 564.133 0. M. Ivanova and A. D. Gel’man, Zhzcr. neorg. Khirn., 1958, 3, 1334; R. A.134 B. N. Ivanov-Emin and E. A. Ostroumov, Zhur. neorg. IUzim., 1959, 4, 71 [27].135 13. Hoppe, Angew. Chein., 1959, 71, 457.‘‘C-HMe,I 0-Me7 ’ 0 - C ( \d/H-f-/C-o~Ptx,4ngew. Chem., 1959, 71, 408.Leblanc, J . Amer. Chem. SOC., 1957, 79, 2649.Golovnya and 0. M. Ivanova, ibid., p. 1347SHARP: THE TRANSITION ELEMENTS. 147ment between the lattice constants reported by the two sets of w0rkers.l3~Reaction of yttrium or samarium chlorides with lithium borohydride intetrahydrofuran gives the chloro-diborohydrides, MC1(BH4),.137 Reductionof anhydrous neodymium trichloride with metallic neodymium gives a darkgreen dichloride.This is a new oxidation state for neodymium; a darkpurple di-iodide has also been prepared.138 The action of fluorine on a mix-ture of alkali-metal chloride plus Pr6Oll gives hexafluoropraseodymates(1v) ,M,PrF, (M = Na, K, Rb, Cs). These are yellowish solids, immediatelyhydrolysed by water.139The Actinides.-Phases in which the components have the ratios 3 : 1,7 : 6, 1 : 2, and 1 : 4 have been isolated from the system LiF-ThF,; forNaF-ThF, the phases present are 4 : 1, 2 : 1, 3 : 2, 1 : 1, and 1 : 2 in the twocomponents.140 A quantitative comparison has been made of the extractionof niobium, tantalum, and protactinium from hydrochloric acid solution by 2,4-dimethylpentan-2-01 (di-isopropylcarbinol) and tributylamine.Varioushydroxy-chloride species from Pa(OH)Cl,+ to PaC1,2- are present in theprotactinium s01ution.l~~ The black solid which is formed when uraniummetal reacts with hydrochloric acid is an active form of U304.142 The addi-tion of alkali to a solution of uranyl nitrate and urea precipitates urea saltsof nitrouranic acid [UO,(NO,)OH] and of uranic acid [H,UO,,H,O]. This istaken to prove the existence of these acids as intermediates in the formationof ~ r a n a t e s . ~ ~ ~ Structural studies have been made on two uranyl salts.Sodium uranyl acetate has a linear 0-U-0 group, the uranium also beingsurrounded by three bidentate acetate ligands in the central ~lane.1~4 Thereis a very similar arrangement in bis(triethy1 phosphate)-uranyl nitrate, acomplex closely related to those used in the solvent extraction of uranium.145Phase studies on the BaF,-UF, and SrF,-ThF, systems have shown theexistence of a new compound, 2BaF,,3UF4, in the former; there is nosimilar compound in the latter.146There has been a noticeable decrease in the amount of published workon the chemistry of the transuranic elements this year.A series of shortreviews on these elements has been pub1i~hed.l~~ Full details of the prepar-ation and properties of neptunium hexafluoride-first prepared on a micro-gram scale in 1946-have now been given. It has m. p. 54.4", b. p. 55-2",136 G. A. Kudintseva, M. D. Polyakova, G.lr. Samsonov, and B. RI. Tsarev, Fiz.Metall. i 1Matallov., 1968, 6, 272; V. S. Neshpor and G. V. Samsonov, Zhur.fiz. Khim.,1958, 32, 1328; H. A. Eick and P. W. Gilles, J . Anzer. Cham. Soc., 1959, 81, 5030.137 A. Rrukl and K. Rossmanith, Monatsh., 1959, 90, 481.138 L. F. Drudingand J. D. Corbett, J . Amer. Chem. SOC., 1959 81 5512.139 R. Hoppe, Angew. Chem., 1959, 71, 457.140 R. E. Thoma, H. Insley, B. S. Landau, H. A. Friedman, and W. R. Grimes,J . Phys. Chem., 1959, 63, 1266; L. A. Harris, G. D. White, and R. E. Thoma, ibid.,p. 1974.141 A. T. Casey and A. G. Maddock, J . Inorg. Nuclear Chem.., 1959, 10, 289.142 R. C. Young, J . Iutorg. Nuclear Chem., 1958, 7, 418.143 P. S. Gentile, L. H. Talley, and T. J. Callopy, J . Inorg. Nuclear Chem., 1959,144 W. H.Zachariasen and H. A. Plettinger, Acta Cryst., 1959, 12, 526.145 J. E. Fleming and H. Lynton, Chem. and Ind., 1959, 1409.146 R. W. M. D'Eye and I. F. Ferguson, J., 1959, 3401.147 J. Chcm. Edztc., 1959, 36, 15, ct seq.10, 110148 INORGANIC CHEMISTRY.and is an orange solid which gives a colourless v a ~ 0 u r . l ~ ~ K,PuCl, andpossibly K,PuC15 have been shown to exist in the KCl-PuC1, ~ystem.14~Jorgensen has considered the spectra of actinide ions and concludes thatonly 5f electrons occur outside the radon shell for ions of charge greaterthan 3+. He points out that there is no necessary correlation between thepresence of f electrons and constant tervalency 150-a point which is veryrelevant in view of the increasing number of " anomalous " valency statesof the rare-earth elements.Titanium, Zirconium, and Hafnium .-The structure of baddeley it e-monoclinic 21-0,-has been redetermined and it has been shown that eachzirconium atom is surrounded by seven oxygen atoms at distances varyingfrom 2.04 to 2-22 A (30).Hafnium dioxide also has0 Zr one form which is isomorphous with badde1e~ite.l~~0 0 An X-ray and thermal analytical study of thesystems M,Ti205-TiO, has shown the existenceof the phases M,Ti,O,, M2Ti409, and M2Ti50,,(30) (M = Rb and Cs).15, In the system M,O-21-0,phases isolated are Li,ZrO,, Li,ZrO,, Li2Zr205, NaZrO,, three forms ofK,Zr,O,, and Rb2Zr205.163 In a preliminary account of the structure of(C,H5)TiCl2*O*TiC1,(C5H5)-prepared by the partial hydrolysis of cyclo-pentadienyltitanium trichloride-it has been stated that the Ti*-Ti linkis linear; d-p overlap between the orbitals of titanium and oxygen wouldprobably account for this type of structure.la A very complete study of thesulphides, selenides, and tellurides of titanium, zirconium, hafnium, andthorium has been reported this year.Phases present are MX, M2X3, andMX, (M = Ti, Zr, Hf, Th; X = S, Se, Te).15j The reaction betweenzirconium disulphide and zirconium dioxide gives 21-0S.l~~ Titaniumsulphochloride, TiSCI,, which has been postulated in several previousreactions, results from the reaction between titanium tetrachloride andhydrogen sulphide in the presence of carbon disulphide. The systemTiC1,-H2S may be summarised< 0" > 0" > 136"TiCl, + H2S .-> TiCl,,H,S - TiSCI, - TiS,.15'The reaction between titanium@) bromide and iodide and ammonia hasbeen studied in detail.In organic solvents 2- and 6-ammoniates result,but in liquid ammonia there is ammonolysis to [TiX,(NH,),-,]2- ions. At-36" compounds of stoicheiometry TiX4,8NH, are formed; these contain148 J. G. Malm, B. Weinstock, and E. E. Weaver, J . Phys. Chem., 1958, 62, 1506.149 R. Benz, M. Kahn, and J. A. Leary, J . Phys. Chem., 1959, 63, 1983.150 C. K. Jsrgensen, Mol. Phys., 1959, 2, 96; see also W. T. Carnal1 and P. R.151 J. D. McCullough and K. N. Trueblood, Actu Cryst., 1959, 12, 507; J. Adam152 0. Schmitz-DuMont and H. Reckard, Monatsh., 1959, 90, 134,153 H.-A. Lehmann and P. Erzberger, 2.unorg. Chem., 1959, 301, 233.154 P. Corradini and G. Allegra, J . Amer. Chem. Soc., 1959, 81, 5510.155 F. K. McTaggart and A. D. Wadsley, Austral. J . Chem., 1958, 11, 445; J. Bearand F. K. McTaggart, ibid., p. 458; F. K. McTaggart, ibid., p. 471; F. K. McTaggartand A. Moore, ibid., p. 481.156 A. Clearfield, J . Amer. Chem. Soc., 1958, 80, 6511157 P. Ehrlich and W. Siebert, 2. anorg. Chem., 1959, 301, 288.Fields, J . Amer. Chem. SOL, 1959, 81, 4445.and M. D. Rogers, ibid., p. 951SHARP : THE TRANSITION ELEMENTS. 149mainly ammonium halide and TiX(NH,), species. On thermal decom-position, TiBr4,8NH, gives TiBr4,2NH, as a red sublimate, with a residueof TiNBr ; TiI,,8NH3 gives TiN.158 Titanium and zirconium tetrachloridesreact with lithium dialkylamides to give compounds M(NR,),.The ethylderivatives are liquid a t room temperature ; they undergo aminolysis withhigher amines, e.g., piperidine, to give solidsC,HioNH Ti(NEt,), - Ti(NC5Hlo), + 4NHEt,Substituted piperidines show considerable steric effects, and the reactionbetween Ti(NMe,), and %met hylpiperidine yields Ti( NMe,) (NC,H,Me),The complexes Na3TiC16, K3TiCl6, K,TiCl,, and K,TiBr, have been foundin the systems NaC1-TiCl,, KCl-TiCl,, KBr-TiBr,.lGO Fluorination oftitanium alkoxides with antimony trifluoride gives esters of fluorotitanic acid,Ti(OR), + SbF, + Sb(OR),,3Ti(OR),F--t 3Ti(OR),F (R = Et, Pr, Bu).The intermediates have been isolated and the esters may also be preparedby the reaction between titanium alkoxides and acetyl fluoride.lslVanadium, Niobium, and Tantalum.-The structure of V,O, has beendescribed; the lattice consists of V06 octahedra joined together by sharingcorners, edges, and faces.Where the octahedra share faces the V-V dis-tance is 2-74 A (in metallic vanadium it is 2.62 A); the octahedra arejoined together by edges to give parallel rows.162 K,V& has a layerstructure in which vanadium atoms are surrounded by square or trigonalpyramids of oxygen atoms, the pyramids being joined by sharing basalcorners.163 pH measurements on rapidly hydrolysed vanadate solutionsshow that the only ions present are VlOO286-, HVl00,s5-, and H2VloOzs4-;in pyrovanadate solutions the V,0,4- and HVO,,- ions are in equi1ibrium.lMSpectrophotometric analysis also points to the presence of the H2V100,84-ion as a hydrolysis product of the vanadyl ion, in agreement with previousresults from potentiometric tit ration^.^^^ Use of an ultracentrifuge methodhas shown that decavanadate species are present in the orange-red isopoly-vanadates.166 A ternary nitride, Li,VN,, containing pentapositive vana-dium, is formed by heating lithium and vanadium nitrides under an atmo-sphere of nitrogen at 680".The structure is based on an anti-fluoritelattice ; the corresponding niobium and tantalum compounds were alsoprepared.167 Vanadium trichloride reacts with phosphine oxides to givecomplexes of the type VCl,(OPR,),. Tertiary aliphatic phosphines react15B G. W. A. Fowles and D. Nicholls, J., 1959, 990.159 D. C.Bradley and I. M. Thomas, Proc. Chem. Soc., 1959, 225.160 P. Ehrlich, G. Kaupa, and K. Blankerstein, 2. anorg. Chem., 1959, 299, 213.161 A. B. Bruker, R. I. Frenkel', and L. 2. Soborovskii, Zhur. obshchei Khim., 1958,lBZ S. Asbrink, S. Friberg, A. Magndi, and G. Anderson, Acta Chem. Scand., 1959,164 J. Meier and G. Schwarzenbach, Chimia (Switz.), 1958, 12, 328.165 L. Newman and K. P. Quinlan, J . Amer. Chem. SOL., 1959, 81, 547; see F. J. C.Rossotti and H. Rossotti, J . Inorg. Nuclear Chem., 1956, 2, 201.166 0. Glemser and E. Preisler, Naturwiss., 1959, 46, 474.167 R. Juza, W. Gieren, and J. Haug, 2. anorg. Chem., 1959, 300, 61.28, 2413.13, 603.A. Bystrom and €3. T. Evans, jun., A d a Chem. Scand., 1959, 13, 377150 INORGANIC CHEMISTRY.similarly, but tricyclohexyl- or triphenyl-phosphine gives products of varyingmolecular ratios which consist partially of dimers [VCl,PR,],.168The systems Li,O-Nb,O, and Ag,O-Nb,O, are very similar169 to thesystem Na,O-Nb,O, reported on last year.Tantalum pentachloride reactswith lithium dialkylamides to give volatile tantalum penta(dialky1amides) -159The niobium chlorides have received a thorough study. Niobium trichlorideexists over a composition range NbCl,.,, to NbCl,.,. Stoicheiometric nio-bium dichloride is formed by the reaction between niobium and NbC1,.67or NbCl, or by the reduction of the pentachloride with hydrogen. There isno evidence for a rnono~hloride.~~~ The oxyhalides of niobium and tantalumhave been reexamined and the existence of NbOCl,, NbOBr,, TaOBr,, andTaOCI, has been established.The first three are prepared by reactionbetween oxygen and the pentahalide; TaOCl, results from the pyrolysis oftantalum pentachloride m0n0etherate.l~~ Niobium tetraiodide has a struc-ture in which NbI, octahedra share opposite edges, the two niobium atomsbeing shifted from the centres of the octahedra towards each other to takepart in metal-metal bonding. The metal-metal distance is 3-2 A com-pared with the distance between octahedra centres of 3.83 A.172 Niobiumis effectively octahedrally co-ordinated in NbOCl,, the octahedra againsharing edges, but there is no evidence for metal-metal bonding.173M1MVC16 complexes have been studied for MV = Nb and Ta. All thepossible salts exist where MI is an alkali metal except for LiNbC1.,174 In thesystems H,O-NbF,-HF and H,O-TaF5-HF the following phases havebeen found to represent successive stages of hydrolysis : HNbF6,H20,HNb2Fl1,4H,O, Nb,05,2H20 ; HTaF5,1-5H,0, HTa2F,,,4.5H,0,T%O,, 1*4H,0.175Chromium, Molybdenum, and Tungsten.-The preparations of chromousoxide have been re-investigated, and a product with a CrN cubic structurehas been obtained by heating chromium carbonyl to between 250" and550°,176 The structure of black ferromagnetic chromium oxide, CrOrI4-prepared by thermal decomposition of Cr0,-has been confirmed as beingof the rutile type,177 but it is considered from magnetic evidence that thesolids of formal oxidation number -4.5 that result from the interaction ofCr(II1) and Cr0,2- in solution are hydroxy-complexes [Cr(OH),]HCrO, or[Cr(OH),],Cr04.178 KCr,08, which is prepared by melting chromium tri-166 K.Issleib and G. Bohn. 2. anorg. Chem., 1959, 301, 188.lbS A. Reisman and F. Holtzberg, J. Amer. Chem. Soc., 1958, 80, 6503; see Ann.170 H. Schafer and K.-D. Dohmann, 2. anorg. Chem., 1959, 300, 1.171 F. Fairbrother, A. H. Cowley, and N. Scott, J . Less Common Metals, 1959, 1,173 L. F. Dahl and D. L. Wampler, J . Amer. Chem. Soc., 1959, 81, 3150.173 D. E. Sands, A. Zalkin, and R. E. Elson, Acta Cryst., 1959, 12, 21.174 K. Huber, E. Jost, E. Neuenschwander, M. Studer, and B. Roth, Helv. Chim.Ada, 1958, 41, 2411; A. P. Palkin and N. D. Chikanov, Zhur. neorg. Khim., 1959, 4,898 [4Oi].175 N. S. Nikolaev and Y u .A. Buslaev, Zhur. neorg. Khim., 1959,4, 205 [84]; Yu, A.Buslaev and N. S. Nikolaev, ibid., p. 465 [210].H. Lux and G. Illmann, B e y . , 1959, 92, 2364.l77 K.-A. Wilhelmi and 0. Jonsson, Acta Chem. Scand., 1958, 12, 1532.178 H.-L. Krauss and G. Gnatz, B e y . , 1959, 92, 2110.Reports, 1958, 55, 155.206; W. A. Jenkins and C . M. Cook, jun., J . Inorg. Nuclear Cham., 1959, 11, 163SHARP: THE TR-4NSITION ELEMENTS. 151oxide with potassium dichromate, has tervalent chromium ions in octahedralco-ordination and sexavalent ions in tetrahedral co-0rdination.1~~ A com-plete structure determination has been carried out on monoclinic (NH,),CrO,.This compound contains a Cr2+ ion surrounded by a deformed pentagonalbipyramid of two superoxide ions and three ammonia molecules.l*O Thereaction of dibenzenechromium with di-t-butyl peroxide at 90" yieldsCr(OBu),, a deep blue solid, m.p. 37-38°.1s1 The oxidation of Cr2+ aquo-ions with certain reagents gives bridged binuclear Cr(m) cationic species ;similar binuclear ions are produced by boiling Cr(m) solutions.182Chomium(I1 and 111) complexes with phosphines and phosphine oxides -the complexes being of the types K,PH[Cr(SCN),(PK,)2], [(R,P),CrCI,],,Cr( SCN),( OPK,),, CrCl,( PR,) 2, CrCl,( OPR,),-have been described.lS3Acidification of molybdates is considered from pH curves to give aheptamolybdate, probably Mo70246- ; the mononuclear species present insuch solutions appear to be HMo0,- and hf0042-.184 However, from electro-metric and spectrophotometric studies it is considered that the main speciespresent is a tetram01ybdate.l~~ The presence of a Mo702,6- ion is in agree-ment with the existence of this ion in crystalline solids.The basicities ofheteropoly-acids have been measured by a spectrophotometric methodinvolving their influence on the ionisation of Methyl Orange. By usingresults from coagulation studies to establish the degree of agglomeration,the following formuk have been derived : H,COA!!O,O,,, H8CeMol,0,,,H,SiWl,O,,, H7P\V1,0,, H6p,~V,,0,,.1s6 Molybdenum hexacarhonyl doesnot give an arenemolybdenum tricarbonyl by reaction with henzoic acid butyields, instead, molybdenum( IT) ben20ate.l~~ A new molybdenum oxy-sulphide, MOOS,, results from the thermal decomposition of (NH4)2M~02S2.188The reactions of molybdenum dichloride have been extensively investigated.In general, it reacts as if it contained a quadrivalent cation, Mo,C184+, thereactions of this ion being very similar to those of the stannic ion.It isconcluded that in Mo,Cl,,, the molybdenum is effectively Mo(vI), employingall nine molybdenum orbitals, the complex cation thus having no reducingproperties.189 Two molybdenum oxybromides, Mo0,Br2 and MoOBr,,have been described; the latter is the compound previously described asMoBr4.190 Molybdenum pentachloride has a dimeric structure in the solidstate, the molybdenum having octahedral co-ordination.lgl The phases179 K.-A. Wilhelmi, A d a Clwm. S c a d . , 1958, 12, 1965; W. Klenim, 2. aizorg. Clzem.,180 E.H. McLaren and L. Helmholz, J . PJys. Chewz., 1959, 83, 1279.181 N. Hagihara and H. Yamazaki, J . Amer. Chem. SOC., 1959, 81, 3160.lE2 M. Ardon and R. A. Plane, J . Amer. Chem. Soc., 1950, 81, 3197; J. A. Laswickand R. A. Plane, ibid., p. 3564.Ia3 K . Issleib and A. Tzschach, 2. anorg. Chem., 1958, 297, 121; K. Issleib andH. 0. Frolich, ibid., 1959, 298, 84; K. Issleib, A. Tzschach, and H. 0. Frblich, ibid.,p. 164.1959, 301, 323.183 Y . Sasaki, I. Lindqvist, and L. G. Sillh, J . Inorg. Nuclear Chem., 1959, 9, 93.185 Y. Cannon, J . Inorg. Nuclear Chem., 1959, 9, 252.187 E. W. Abel, Apar Singh, and G. Wilkinson, J., 1959, 3097.188 G. Spengler and A. Weber, Ber., 1959, 92, 2163.189 J. C. Sheldon, Nature, 1959, 184, 1210.1*0 C. Durand, R.Schaal, and 1'. Souchay, Compt. rend., 1959, 248, 979.191 n. E. Sands and A . Zalkin, Acta Cryst., 1959, 12, 753.E. MatijeviC and M. Kerker, J . Arrzer. Chem. Soc., 1959, 81, 5560152 INORGANIC CHEMISTRY.present in the system HF-MoF,-H,O have been shown to be MoF,,H,MoO,F,, 1.5H20, H,MoO,F,,H,O, and MoO,,H,O.~~~There has been a chemical and physical investigation of the phasesprecipitated from tungstate solutions by acid. W03,2H20 and W03,H20have been identified as hydrates by comparison with the isomorphousmolybdenum compounds; a new compound, Na,O(WO,,H,O), (a = 4-10),has been isolated from this system.lg3 In aqueous solution 12-silicotungsticacid, H,SiW,,O,, has a molecular arrangement similar to that found for thes0lid.19~ Thallium-tungsten bronzes, Tl,WO, (x = 0-19-0*36), may beprepared by gentle reduction of thallium tungstate or mixtures of thalliumcarbonate and tungstic oxide. The univalent ion, M, in tungsten bronzesM,WO,, is considered to give rise to local energy levels in the forbidden gapbetween the conduction and the valency bands of tungsten trioxide.lg5The ammonolysis of tungsten hexackloride, either in liquid ammonia or inan inert solvent, gives WCl,(NH,),-, compounds; WCl,(NH,), reacts withammonium chloride to give [WC&(NH2),I2- ions. Thermal decompositionof the WCL(NH,),_, derivatives gives WC12(NH),.lg6Manganese, Technetium, and Rhenium.-Nuclear magnetic resonance andinfrared studies on precipitated manganese dioxide have shown the presenceof hydroxyl groups, and it is suggested that the observed non-stoicheiometryis due to replacement of oxide ion by hydro~y1.l~~ Manganous oxide be-comes non-stoicheiometric as the oxygen pressure is raised from 10-lo to 10-2atm.at 1500-1650". In this case the defect structure is considered to bedue to cation vacancies.1gs The blue solutions obtained by dissolvingmanganese dioxide in concentrated potassium hydroxide contain equimolarquantities of Mn(v) and Mn(I1r). Manganese(1v) appears to be thermo-dynamically unstable in such alkali solutions.199 Manganese oxysulphide,MnOS, is prepared by the action of oxygen on manganous sulphide; withhalogens, manganous sulphide gives halogeno-sulphides, MnSX,.200A review of the chemistry of technetium has been published this year.201Polarographic studies have established the existence of Tc(-I) in reducedpertechnetate solutions; the nature of this species is probably similar tothat of Re(-I) discussed below.202 Other new valency states of technetiumhave been characterised as resulting from the reaction between potassiumchlorotechnetate(1v) and o-phenylenebisdimethylarsine (D) (compounds31-35).," A reaction scheme for these changes is given opposite.Nuclear magnetic resonance studies have shown the presence of arhenium-hydrogen bond in rhenide solutions, and it seems likely that species192 N.S. Nikolaev and A. A, Opalovskii, Zhur. neorg. Khim., 1959, 4, 1174 [532].193 M. L. Freedman, J. Amer. Chem. SOL, 1959, 81, 3834.194 H. A. Levy, P. A. Agron, and M.D. Danford, J. Chem. Phys., 1959, SO, 1486.195 M. J. Sienko, J. Amer. Chem. SOC., 1959, 81, 5556.lg6 G. W. A. Fowles and B. P. Osborne, J . , 1959, 2275.197 0. Glemser, Nature, 1959, 183, 943.19* M. W. Davies and F. D. Richardson, Trans. Faraday SOC., 1959, 55, 604.199 K. A. K. Lott and M. C. R. Symons, J., 1959, 829.200 S. S. Batsanov and L. I. Gorogotskaya, Zhur. neorg. Khim., 1959, 4, 62 [24].201 G. E. Boyd, J. Chem. Educ., 1959, 36, 3.2O2 R. Colton, J . Dalziel, W. P. Griffith, and G. Wilkinson, Nature, 1959, 183, 1755.2O3 J, E. Fergusson and R. S. Nyholm, Nature, 1959,183. 2039SHARP THE TRANSITION ELEMENTS. 153such as [HRe(OH) (H20),]- or [H,Re(OH),(H,O)]- are present.202 Tri-methylsilyl per-rhenate, Me3Si*O*Re03, is prepared by the action of rheniumheptoxide on bistrimethylsilyl ether or by the interaction of silver per-rhenate and trimethylsilyl chloride.204 The per-rhenate ion is tetrahedralin aqueous solution but the existence of greenish-yellow Ba,(ReO,),, of un-known structure, has been confirmede205 Many complexes of rheniumtetraiodide and trichloride have been described; rhenium tetrabromide isprepared in the same way as the iodide205" and gives similar complexes.When the tetrabromide is heated in oxygen at 100-120" it gives colourless,volatile per-rhenyl bromide, Re0,Br.This sample appears more likely tobe true Re0,Br than the dark blue solid described previously.206 Darkgreen K5Re1(CN)6,3H20 may be prepared by reducing rhenium(&)with potassium amalgam.207solutionsD in refluxK,TcTVCI6 ____).~c~~~D,CI,ICI - CTC~~~D,BI-,]B~aq. EtOH orange (3 I ) LlBr In EtOH red (32)raflux Lil in EtOH / -reflux in excessTcTID,I, - [Tc~~'D,I,]I -+ [TC~~~D,~,]~,brown (34) EtOH or SOa deep red t o IP (35)black (33)Iron, Ruthenium, and Osmium.-Nuclear magnetic resonance and infra-red studies have shown that ferric hydroxide, Fe(OH),, cannot be precipitatedas a distinct phase, there being continuous loss of water and formation ofcondensed phases down to o(-Fe203.1g7 Schwertmann has made a verydetailed study of the conditions necessary for the formation of the variousiron oxides and oxy-hydroxides.208The infrared spectrum of ruthenium tetroxide is in agreement with atetrahedral structure for this molecule.209 Ruthenium(1v) species whichhave been prepared in aqueous solution by reduction of ruthenium tetroxideare generally polymeric, being of the form Ru(OH),,xH,O.Re-oxidationof these polymers requires up to eight equivalents of oxidising agent and itis suggested that there is induced oxidation of the bound water by ruthen-ium(Iv).210 Many ternary oxides of the alkaline-earth metals with Ru, Rh,M,DMIVO,, M,IIMrVO,, and M,11M2rV0,.211 The action of chlorine onruthenium trichloride gives a higher volatile chloride. The formula isunknown, but it has been suggested that it is the tetrachloride, RuCI4.212Ir, and Pt have been described this year; they are of the types MIIMIVO 3,204 M. Schmidt and H. Schmidbaur, Ber., 1959, 92, 2667.205 J. E.Earley, D. Fortnum, A. Wojcicki, and J. 0. Edwards, J . Amer. Chem. SOC,,205a Ann. RefJorts, 1958, 55, 161.206 R. Colton and G. Wilkinson, Chem. and Ind., 1959, 1314.207 D. Clams and A. Lissner, 2. anorg. Chem., 1958, 297, 300.208 U. Schwertmann, 2. anorg. Chem., 1959, 298, 337.209 R. E. Dodd, Trans. Faraday SOC., 1959, 55, 1480.210 F. P. Gortsema and J. W. Cobble, J . Amer. Chem. SOC., 1959, 81, 5516.211 J. J . Randall, jun., and R. Ward, J . Amer. Chem. SOL, 1959, 81, 2629; J. J.218 S. A. Shchukarev, N . I. Kolbin, and A. N. Ryabov, Zhur. neorg. Khim., 1959, 4,1959, 81, 1295.Randall, jun., and L. Katz, Acfa Cryst., 1959, 12, 519.1692 [763]154 INORGANIC CHEMISTRY.Reduction of cis-R,MX, [R = C,H,(PMe,),, C,H,(PEt,),, or o-C,H,(AsMe,),;M = Ru, 0 s ; X = halogen] with lithium aluminium hydride gives cis-R,MHX.The tram-complexes are not reduced, and the hitherto unknowncis-complexes were prepared for the first time. The hydrides are quitestable and can be stored out of contact with moisture and oxygen; theosmium derivatives are less stable than the ruthenium hydrides.129Cobalt, Rhodium, and Iridium.-Electron-diffraction studies have shownthat the substance precipitated from cobalt(I1) solutions by the action ofhydrogen sulphide is mainly Co&. When heated to 450" this changes toC O ~ S ~ . ~ ~ ~ It has previously been postulated that the peroxydicobalt coni-plexes, e.g., [(NH,),CO-O*O*CO(NH,),]~+ contain both ter- and quadri-valentcobalt, but electron-spin resonance studies have demonstrated theequivalence of the cobalt atoms.214 The first proof of the existence oftetrahedral co-ordination for cobalt(II1) ions has been given in the structureof the 12-tungstocobaltiate ion.The ease of reduction of the cobalt(II1)compound shows that this configuration provides relatively small stabilisationfor the 3+ state. The cobalt(I1) derivative also has tetrahedral co-ordin-ation.215 In the structure of bisacetylacetonecobalt(11) dihydrate there is atetragonally distorted octahedral co-ordination about the cobalt atom. Theorganic ligands are nearly planar but the cobalt is out of the plane.216 Sodiumchlorite is a good reagent for the oxidation of cobalt(11) to cobalt(II1) com-plexes; under suitable conditions chlorite-containing complex anions areformed.21' The action of potassium amide in liquid ammonia on cobalt-ammine hydrates has been studied.Various hydroxy-amido-complexesresult and these undergo further changes on treatment with the acidammonium nitrate.21* Complex cobalt (11) azide ions such as [CO(N,),]~-are formed in aqueous solution ; the tetraphenyl-phosphonium and -arsoniumsalts have been isolated.219 A complete structural study of trans-[Co(en),BrJBr,HBr,2HZ0 has shown the existence of [H20*H*OH2+] cations;the ethylenediamine is in the gazdche configuration.2Zo The deep green saltprepared by boiling ammonium chloroiridate( 111) with sulphuric acid has beenformulated as I<,[N(Ir(H,O) (SO,),),] on the basis of spectroscopic and mag-netic considerations; the nitrogen is three-covalent as in amines.221Nickel, Palladium, and Platinum.-Most of the work on nickel publishedthis year has been on various aspects of the co-ordination of the metal.The presence of the tetrahedral NQ2- ion has been established in solutionsof nickel chloride in fused pyridinium chloride, czesium chloride, and czesiumchlorozincate ; the ion is distorted in fused lithium chloride.222 Tetra-21s P.s. Aggarwal and A. Goswami, 2. Nalzarforsch., 1959, 14b, 419.214 E. A. V. Ebsworth and J. A. Weil, J . Phys. Chem., 1959, 63, 1890.215 L. C. W. Baker and V. E. Simmons, J . Amer. Chem. SOC., 1959, 81, 4744.216 G. J. Bullen, Acta Cryst., 1959, 12, 703.217 P. Spacu, C . Gheorghiu, M. Brezeanu, and S. Popescu, Rev. Chim. (Acad. R.P.R.),$18 0.Schmitz-DuMont and W. Hilger, 2. anorg. Chem., 1959, 300, 175.219 P. Senise, J . Amev. Ghem. SOC., 1959, 81, 4196.220 S. Ooi, Y . Komiyama, Y . Saito, and H. Kuroya, Bull. Chem. SOC. Japan, 1959,221 C. K. Jarrgensen, Actu Chem. Scund., 1959, 13, 196.225 D. M. Gruen and R. Id, McBeth, J . Phys. Chem., 1959, 63, 393.1958, 3, 127.52, 263SHARP : THE TRANSITION ELEMENTS. 155chloronickelates, R,NiCl, [R = Et4N+, Ph,MeAs+], have been preparedfrom alcoholic solution. From conductivity, spectroscopic, magnetic-susceptibility, and crystallographic studies it is concluded that there istetrahedral co-ordination about the nickel in these salts also.223 Stereo-chemical considerations would predict that the yellow complexes formed bythe action of triarylphosphine oxides on nickel(I1) salts should have tetra-hedral co-ordination about the metal; magnetic and spectroscopic data arein favour of this config~ration.~~~ The ligand-field theory has been appliedto the spectra of these tetrahedral complexes with very satisfactory results.225The position of the " planar " nickel complexes with anomalous magneticmoments has also reached a more satisfactory state.It is now believed thatdiamagnetic + paramagnetic transitions in these complexes are not dueto a change in stereochemistry but to a change in the strength of the fieldassociated with the ligands. The complexes are, in fact, pseudo-octahedral,the two apical ligands causing a perturbation from a singlet to a tripletground state.226 This perturbation can be effected merely by temperaturechanges ; this aspect of the problem has been studied for salicylaldiminederivative^.^^' Diamagnetic bis- (N-methylsalic ylaldimine)nickel(~r) , whichgives paramagnetic solutions, has a trans-planar arrangement about thenickel atom; there is no possibility of metal-metal bonding.228 It has beenshown that nickel@) forms a hexacyano-anion, [Ni(CN),]4-.229The absorption spectra of [PdX4I2- (X = C1, Br) and [Pd2X6I2- (X = C1,Br, I) ions depend upon the solvent and it is concluded that the ions areactually six-co-ordinate in solution.It appears possible that there is alsooctahedral co-ordination in the solid state.230 Platinic chloride has a tetra-hedral arrangement of chlorine atoms about the platinum; this seems to bethe first report of tetrahedral co-ordination for this element.231 The deepgreen colour of Pt (CH,NH,),PtCl, is associated with metal-metal interactionin the Physicochemical measurements have been made on thetwo chloro-acetylacetonates of platinum.It is concluded that the orangeform has the structure K[Cl,Ptac] and that the yellow form is K[C1Ptac2](ac = acetylacetone group). One of the acetylacetonate groups in theyellow form is m ~ n o d e n t a t e . ~ ~ ~ Further work has been published on thecomplexes that result in removal of protons from the amino-groups ofligands in platinum complexes. The reaction of bisethylenediamine-platinum(I1) iodide with excess of potassium amide in liquid ammonia givesKIPtxl(en-H) (en--2H)].The unstable species [Ptl(en) (en-H)] occurs223 N. S. Gill and R. S. Nyholm, J., 1959, 3997.224 F. A. Cotton, E. Bannister, R. Barnes, and R. H. Holm, Proc. Ckenz. Soc., 1959,22s A. D. Liehr and C. J. Ballhausen, Ann. Phys., 1959, 2, 134; B. R. Sundheim and228 G. Maki, J . Chem. Phys., 1958, 29, 1129; C. J. Ballhausen and A. D. Liehr,227 H. C. Clark and R. J. O'Brien, Canad. J . Chem., 1959, 3'9, 436.228 E. Frasson, C. Panattoni, and L. Sacconi, J . Phys. Chenz., 1959, 63, 1908.229 L. KiSovA and V. CuprovA,, Chem. Listy, 1958, 52, 1422.230 C. M. Harris, S. E. Livingstone, and I. H. Reece, J., 1959, 1606.232 M. T. Falqui, Ann. Chim. (Rome), 1958, 48, 1160.232 S. Yamada and R. Tsuchida, Bull. Chem. Soc. Japan, 1958, 31, 813,158.G.Harrington, J. Chem. Phys., 1959, 31, 700..J. Amer. Chem. SOL, 1959, 81, 538; see also C. Furlani, Gazzetta, 1958, 88, 279.A. A. Grinberg and I. N. Chapurskii, Zhur. neorg. Khim., 1959, 4, 314 [137]156 INORGANIC CHEMISTRY.transitorily in the reduction of [Pt(en)2]2+ with potassium in the presence ofpotassium amide.234Copper, Silver, and Gold.-The bonding in copper compounds continuesto excite considerable interest. The paramagnetic resonance spectrum ofcopper acetate is taken to confirm the existence of a &bond between themetal atoms in the binuclear molecule.235 The magnetic susceptibilitiesof cupric salts of substituted acetic acids and of cro-dicarboxylic acids alsofavour the existence of metal-metal bonding in the crystalline solids exceptin the case of cupric malonate. It is possible that geometrical considerationsrule out metal-metal bonding for copper salts of [CH2In-2(CO2H), acids whenn is As part of an extensive series of experiments on the variouscopper formates, it has been shown that the normal salt, which does nothave metal-metal bonding, can be “ conditioned ” into adopting a binuclearstructure with 6 bonding between the copper atoms by complexing the metalwith amines or di~xan.~,’ Green bis-salicylaldiminecopper(I1) is isomorphouswith the nickel complex, the atomic arrangement being such that the co-ordination about the copper is truly planar.238 The octahedron of fluorideions about the copper atom in K,CuF, is distorted to give four long (2-08 A)bonds in a plane, the two apical bonds being shortened (1.95 4.239 Crystal-field theory would predict a distorted octahedral co-ordination for copper@),and recent calculations have predicted that the distortion could give eitherfour long and two short bonds or four short and two long bonds as are morenormally found.240 A full structure has now been determined for anhydrouscupric nitrate.Each copper atom is eight-co-ordinate with respect tooxygen; there are two Cu-0 bonds linking Cu and NO, groups in infinitechains parallel to one axis; the other six bonds are to a distorted hexagonof oxygens at right angles to this axis, these oxygens being from nitrategroups which hold the infinite chains together. There is no obvious reasonwhy this structure should give rise to volatile monomers.241 A furtherunusual co-ordination arrangement for copper is found in bis(dimethy1-glyoxime)copper(II) .The structure consists of dimers, the copper atom beingslightly above the plane of four nitrogen atoms, and each copper atom beinglinked further to an oxygen of the other half of the molecule.242 In bothbis(succinonitri1e) copper (I) nitrate 243 and tristhioureacopper(r) chloride 244crystal structure determinations have shown tetrahedral co-ordination aboutthe copper atoms. In the former compound the succinonitrile acts as abidentate ligand and is joined to different copper atoms; the cations, there-fore, form chains through the structure. In the thiourea complex the copper234 G. W. Watt and J. W. Dawes, J . Amer. Chem. SOC., 1959, 81, 8.28s I. G. Ross, Trans. Faraday SOC., 1959, 55, 1057.286 M. Kondo and M. Kubo, J . Phys. Chem., 1958, 62, 1558; 0. Asai, M. Kishita,237 R. L. Martin and H. Waterman, J., 1959, 1359, 2960.238 J. M. Stewart and E. C. Lingafelter, Acta Cryst., 1959, 12, 842.239 K. Knox, J . Chem. Phys., 1959, 30, 991.240 A. D. Liehr and C . J. Ballhausen, Ann. Phys. (N.Y.), 1958, 8, 304; cf. U. dpikand M. H. L. Pryce, Proc. Roy. SOL, 1957, A , 238, 425.241 S. C . Wallwork, Proc. Chem. Soc., 1959, 311.242 E. Frasson, R. Bardi, and S. Bezzi, Acta Cvyst., 1959, 12, 201.243 Y. Kinoshita, I. Matsubara, and Y . Saito, BuK Chem. SOC. Jafian, 1959, 32, 741.244 C. B. Knobler, Y. Okaya, and R. Pepinsky, 2. Krist., 1959, 111, 385.and M. Kubo, ibid., 1959, 63, 96SHARP: THE TRANSITION ELEMENTS. 151shares sulphur atoms with neighbouring tetrahedra. Other cuprates,MCuO, (M = Na, Rb, Cs), have been prepared by heating a mixture of themetal oxide and cupric oxide in oxygen. Lithium oxide gives the loweroxides Li,CuO, and L~,CU,O,.~ Cuprates can also be prepared by oxidisingcupric salts with hypoclilorite.246Argentic oxide prepared by the normal methods has the zinc blendestructure, but it is generally contaminated with other oxides. The peroxy-nitrate, -sulphate, and -fluoride of silver are essentially Ag,O, containingoxide and acid salt impurities. Ag,O, has a cubic lattice with someoxygen defects.,,' Silver(1) NN'-dialkyldithiocarbamates react with thecorresponding thiuram disulphides to give blue solutions in benzene which,from electron-spin resonance studies, are considered to contain bivalentRSAgIISR species. Gold(1) species behave very similarly and, although thegold(m) compound results eventually, it is considered that there is definiteevidence for the presence of gold(I1) species in solution.248 The crystalstructure of aurous iodide shows that there are continuous Au-I chainsthroughout the crystal; the Au-I distance is very short (2-62 Therehas been considerable evidence this year to show that gold(m) can readilyachieve a co-ordination number of six in complexes. The bromoaurateion, AuBr,-, reacts with bromide ion in nitrobenzene and nitromethane to giveAuBrG3-, AuBr,2-, and Au2BrIo4- ions.250 1 ,lo-Phenanthroline and 2,2'-bipyridyl complexes of gold(II1) halides rearrange in non-aqueous solvents :2[Au(phen)X,]+ + 2X-+ [Au(phen)X,]+ + [AuX,]- + phen. It is con-sidered that the ready rearrangement is by way of an intermediate distortedoctahedral arrangement.251 Chloroauric acid reacts with alkali iodides togive complex iodides, MAuI, and M,AulAulIII, (M = Cs and Rb). Thelatter compounds are reminiscent of the complex chloride, Cs2Au2C16, re-ported many years Potassium fluoroaurate, KAuF,, is isomorphouswith the fluorobromate and it is possible that there is a distorted octahedralarrangement about the metal in this complex.253Zinc, Cadmium, and Mercury.-Cadmium alkyls react with molecularoxygen or alkyl hydroperoxides to give alkylperoxycadmium compounds.254Apart from this one paper, work on this group reported during the year has,been mainly concerned with the chemistry of mercury. ,4 combined X-rayand neutron-diffraction study QTI mercuric cyanide has shown that the,NC-Hg-CN groups are not linear and that the deviation from linearity canbest be explained in terms of interaction of the mercury atom with nitrogenatoms in neighbouring groups (36). Hg . N plane is a t an! The N245 W. Klemm, G. Wehrmayer, and H. Bade, 2. Elektrochem., 1969, 83, 56.246 A. Yu. Prokopchik and P. K. Norkus, Zhur. neorg. Khim., 1959, 4, 1359 [Sll].247 B. Stehlik and P. Weidenthaler, Chenz. Listy, 1958, 52, 402; B. Stehlik, P.248 T. Vanngard and S. Akerstrom, Nature, 1959, 184, 183; S. Akerstrom, Arkiv249 H. Jagodzinski, 2. Krist., 1959, 112, 80.250 C. M. Harris and I. H. Reece, Nature, 1958, 182, 1665.251 C. M. Harris, J., 1959, 682; C. 3%. Harris and T. X. Lockyer, ibid., p. 3083.282 A. Ferrari and M. E. Tani, Gazzetta, 1969, 89, 502.253 R. D. Peacock, Chew. and Ind., 1959, 904; see also ref, 17.254 €3. G. Davies and J. E. Packer, J., 1959, 3164.Weidenthaler and J. Vlach, ibid., p. 2230.Kemi, 1959, 14, 403158 INOKGANIC CHEMISTRY.angle of 92" to the plane through the Hg(CN), molecule.255 Complexes ofthe mercurous ion are little known, but it has been shown that oxyanionssuch as pyrophosphate, tripolyphosphate, oxalate, and succinate do formcomplexes.256 A solid which is probably a mercurous complex,Hg,phen,(NO,),, is precipitated from mercurous nitrate solution by o-phen-=N2.70 - -N (37)a n t h r ~ l i n e . ~ ~ ~ Mercurous nitrate also gives a complex with NN'-diacetyl-hydrazine ; this compound very probably has chains (37) running throughthe struc t ~ r e . ~ ~ ~ Bis (trifluoromethylthio)mercury, Hg(S*CF,),, is obtainedin high yield from mercuric fluoride and carbon disulphide at 250". Whenheated to higher temperatures it breaks down to give CF,*SCF, andCF,*S-S*CF,. The mercurial reacts with metallic copper to give (Cu*S*CF&and in aqueous solution reacts with silver nitrate to give Ag*S*CF3. I tundergoes many metathetical reactions with organic halides.259D. W. A. S.A. G. SHARPE.D. W. A. SHARP.255 J. Hvoslef, Acta Chem. Scand., 1958, 12, 1568.2 j 6 T, Yamane and N. Davidson, J . Amer. Chem. SOC., 1959, 81, 4438.257 G. Anderegg, Helv. Chim. Acta, 1959, 42, 344.258 K. Brodersen and L. Kunkel, BEY., 1958, 91, 2698.239 E. H. Man, D. D. Coffmann, and E. L. Muetterties, J . Amer. Chew. SOC., 1959,81, 3575