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J. CHEM. SOC. DALTON TRANS. 1985 411Niobium(iv) Sulphidohalides: Preparation of Nb,X4S, and Nb,X,S,.nL [X =Br or Cl; n = 4, L = NCMe, SMe,, or Tetrahydrothiophene (tht); n = 2,L = PhSGH,CH.SPh]. Crystal and Molecular Structure of Nb,CI,S2.4tht *Michael G. B. Drew, David A. Rice, and David M. WilliamsThe Department of Chemistry, The University, Whiteknights, Reading, RG6 2ADThe niobium(iv) compounds Nb,CI,S, (X = Br or CI) were formed by the reaction of NbX, andSb,S, (2: 1 molar ratio) in CS, at 50 "C. These species contain the [Nb-S-Nb-S214+ moiety. Arange of adducts Nb,X,S,-nL [n = 4, L = NCMe, SMe,, or tetrahydrothiophene (tht); n = 2,L = PhSCH,CH,SPh] were prepared and Nb2CI,S,-4tht was obtained from Nb2CI,S,-4tht by theabstraction of a sulphur atom with PPh,.A crystal of Nb2CI,S,-4tht was found to be monoclinic,space group P2,/n, with a = 19.958(11), b = 12.61 6(8), c = 11.530(10) A, f! = 97.0(1 ) O , andZ = 4.2 741 Independent reflections above background were measured on a diffractometer and thestructure refined to R 0.053. The structure is dimeric with two niobium atoms [Nb-Nb 2.868(2) A]being linked by bridging sulphur atoms. Each metal atom is six-co-ordinate being bound to twochlorine atoms and two ligand sulphur atoms as well as the bridging atoms.,The synthesis and structure of metal-metal bonded speciesinvolving niobium and tantalum is a topic of current interest,a number of niobium(II1) and tantalum(II1) species havingbeen synthesised and structurally studied. 1-3 Recently theserendipitous isolation of two niobium(1v) compounds havingthe formula Nb2X,S,4tht (X = Br or C1, tht = tetrahydro-thiophene) was reported., It was decided in view of currentinterest in metal-metal bonded species and the small number ofdimeric niobium-niobium bonded species known, to investigatesystematically the preparation of these compounds.The background to the study is as follows. The niobiumchalogenide halides of formulation NbX,S (X = Br or C1) canbe obtained by the carefully controlled reaction of niobium(v)chloride or bromide with antimony(II1) sulphide (the reactantsbeing in a 3 : I molar ratio) in carbon disulphide s~lution.~ Thechloride, NbC13S, is lemon-yellow but if this material is left inthe reaction medium for more than 24 h a darker material isobtained that has a niobium to chloride ratio of less than 1 : 3.Further interesting reactions occur when the species NbX,S(X = Br or C1) are treated with tetrahydrothiophene.InitiallyNbX3S*2tht is formed but in CS2 solution complex dispro-portionation reactions take place leading to the formation ofthe niobium(rv) species Nb2X4S34tht [see equation (l)]." Incs3NbX3S*2tht Nb,X4S3*4tht + NbX5-ntht (1)(n = 1 or 2)these niobium(rv) species the two metal atoms are bridged by asulphur atom and a S2 group with the niobium-niobiumdistance being of such a length [2.830(5) A for X = Br and2.844(2) A for X = Cl] that an interaction of some form betweenthe two metal atoms must be present.The mild conditions that led to the formation of aniobium(rv) compound suggest that the change in colourobserved when NbC13S is allowed to stand in its preparativemedium may be evidence for the spontaneous formation ofsome niobium(!v) compounds.Furthermore as the niobium to* Di-~-~ulphido-bis[dichlorobis(tetrahydrothiophene-~)niobium(~v)].Supplementary data available (No. SUP 56107, 7 pp.): thermalparameters, H-atom co-ordinates, remaining bond distances and angles.See Instructions for Authors, J. Chem. Sac., Dalton Trans., 1985, Issue 1,pp. xvii-xix. Structure factors are available from the editorial office.sulphur ratio in Nb2X,S3 is 2:3 it was thought worthwhile totreat NbX, with Sb2S3 in a 2: 1 molar ratio (thus having a Nb: Sratio of 2:3) in an attempt to obtain directly pure Nb2X,S3[equation (2)].A second type of niobium(1v) sulphidohalide is formed whenNbX4*2NCMe is allowed to react with Sb2S3.6 The compoundsformed have been shown to be dimeric in which two sulphuratoms bridge the two metal centres (see below). An alternativeX XX Xroute to these types of compounds would be to take the com-pounds containing the Nb-S,-Nb-S core and to carry outreactions designed to remove a sulphur atom from the S, group.Accordingly reported herein are the results of studies inwhich NbX, and Sb2S3 have been allowed to react in a 2:lmolar ratio together with the attempts to remove a sulphuratom from a S, group in Nb,X,S,.-Results and DiscussionTypical analyses of the products of the reaction of NbX, (X =Br or C1) and Sb2S3 in a 2: 1 molar ratio are in accord with theproducts being Nb2X,S,.Unfortunately all attempts to obtainreproducible sulphur analyses either by the authors, or by com-mercial laboratories were unsuccessful. Similarly, experimentsdesigned to grow single crystals by sublimation were unsuc-cessful. Accordingly in order to characterise the products thecompounds were treated with tetrahydrothiophene (tht) in anendeavour to prepare the well characterised 1 : 4 adducts,Nb2X4S,4tht. In addition a number of other co-ordinationproducts [of MeCN, 1,2-bis(phenylthio)ethane (bpte), an418 J. CHEM. SOC. DALTON TRANS. 1985dimethyl sulphide (dms)] were prepared to ensure that theformation of Nb2X,S, is not a function of the presence of thtand to investigate the absorption bands in the i-r.spectrum thatare characteristic of Nb,X,S3. The analyses of the tht, MeCN,and dms adducts are in accord with the formulationNb2X,S,-4L (L = ligand), while those of (bpte) are inagreement with those required for 1 : 2 compounds (Table 1).Furthermore X-ray powder diffraction patterns of the thtadducts were identical to those of Nb2X,S,4tht (X = Br or CI),whose single-crystal X-ray structures have been determined.,Table 1. Analyses of the adducts (calculated values in parentheses)AdductNb2C1,S34dmsNb2Br4S3-4dmsNb2Br4S34thtNb2CI,S3-4NCMeNb2Br,S34NCMeNb2CI,S3*2bpteNb2Br,S3*2bpteNb2CI4S34thtColourBright greenBright greenGreenGreenDull yellowDull yellowDark brownBrown% Nb27.9 (27.6)21.9 (21.9)23.8 (23.9)19.2 (19.5)31.4 (31.6)24.5 (24.3)20.1 (20.3)16.8 (17.0)% Halogen20.9 (21.1)37.5 (37.6)18.9 (18.3)18.9 (18.3)24.0 (24.1)42.3 (41.7)15.7 (15.5)29.5 (29.2)Finally, each of the reactions leading to the formation ofcomplexes led to the isolation of single products.Thus it isconcluded that the niobium(1v) compounds are formed directlyat low temperatures via the oxidation of two S2- groups to(S,)'- and the concomitant reduction of two niobium(v) atomsto niobium(1v). Recently the compounds NbBr,Se, NbBr,Te,and Nb1,Te (prepared from the elements at approximately1 OOO "C) were shown to be dimeric niobium(1v) compoundscontaining Se,'- or Te,'- group^.^The i.r. and Raman spectra of the adducts are given in Table 2together with the i.r.spectra of Nb,X,S, (X = Br or C1) and theRaman spectrum of Nb,Br,S,; the chloride decomposed in thelaser beam. The modes associated with the co-ordinated ligandsare as seen in other well documented complexes of the variousligands and show the changes from the spectra of the freeligands that have been associated with adduct formation. Thespectrum of bpte has not been assigned but the ligand spectraexhibited by NbzX,S,=2bpte are identical to that ofTaC1,Sabpte in which the ligand adopts a guuche,gauche,transconfiguration.* Assignments of the modes associated with theNb-S-Nb-S2 cores are given in Table 2. The highest energyabsorptions (591-564 cm-') are vibrations involving theITable 2.Vibrational spectra of the complexes (6-200 cm-')Nb2CI,S3"Nb2Br,S3 589w 591s 461mNb2C1,S3-4dms 583w 585m 450s565w 564mNb2Br4S34dms 581m 581m 450s565m 566mNb2CI4S34tht 589m 591m 450s582wNb2Br,S3*4tht 584w 585m 449s569w 571sNb2C1,S3*2bpte" 582w 455s280 (sh)v(S-S) HNb-S-N b) v(Nb-4) or v(Nb-4) v(Nb-Br) Other peaksb-rh-1.r. Raman 1.r. Raman 1.r. Raman 1.r. Raman 1.r. Raman462m 380m,br343s,br315s280s,br355m (sh) 350vs 205s 200s,br340s,br 335m315m 316m335(sh) 338m305m 3 12m290s 29 1 vs340s 340w 205vs,br305m 305w307s 309s 470w288vs 29Om449s 350s 347vs 250m,br 245m 515mb 515wb331s 329s 215s 220m,br 469wb 478mb303s 304m 205m3 50s 466s345s329s3 10s302s280m305m 215s,br321m 325m281s342m 345w 2 lOs,br3 20m 319w289m462vs 381w 383w 260m,br 258m,br451s 349vs 348s451vs 355 (sh) 348m,br 250m,br 245m,br451s 345vs,br 347s 517mbNb2Br,S3*2bpte" 580m 455s 332m,br 245sNb2C14S3-4NCMe 580w 581s 449s 450s 345m,br 359sNb2Br,S3-4NCMe 589w 590s 449s 451s 360s 250brNb2CI4S24tht " 463m (sh) 345vs,br460vs 330m (sh)302sa No Raman data.Probably internal ligand mode. ' v(Nb-N).463m400m' 410m'390wa 4OOm' 410m'518mJ. CHEM. SOC. DALTON TRANS. 1985 419stretching of the S, group; similar assigments having been madefor the spectra of Nb2X4S4 (X = Br or Cl).'-'' It is moredifficult to assign modes to the Nb-S-Nb group. In thecompounds Nb,X,S2m4MeCN, containing Nb-S-Nb-Srings,' bands in the range 47-68 cm-' and 330-320 cm-'were attributed to the Nb-S-Nb modes.Examination of thespectra recorded in Table 2 indicate that for the Nb,Br,S,adducts the comparable bands occur in the regions 462-449cm-' and 355-332 cm-'. The assignment of the lower energyband for the chloride adducts is difficult as one of the Nb-C1modes occurs in the same region. The structures of thechalcogenide halides Nb,X4S3 are likely to consist ofNb-S-Nb-S, fragments that are linked through halogenbridges giving rise to polymeric structures as seen inNb,X4S4.'2*'3All the adducts were diamagnetic which besides confirmingthe presence of some form of magnetic interaction between themetal atoms allowed the measurement of their n.m.r. spectra,The MeCN adducts lacked solubility in suitable solvents but forthe remaining complexes the 'H spectra showed a shift to higherp.p.m. (relative to the free ligand in the same solvent as thecomplex) of the ligand resonances as expected on co-ordination.From the X-ray structure of the tht adducts it is known thatthere are two positions for the ligands, one in which the thtmolecule is trans to a bridging S atom while in the other tht istrans to an S , group.4 The n.m.r.measurements showed noevidence for two ligand sites. The limited n.m.r. facilitiesavailable restricted measurements on these air-sensitive com-pounds to 60 MHz and room temperature and so it provedimpossible to decide if the failure to detect two sets ofresonances for each ligand was caused by magnetic equivalenceof the co-ordination sites or rapid exchange processes.The second aspect of the present study concerned the reactionof niobium(xv) compounds, containing a Nb-S,-Nb-S core,with phosphorus ligands in an attempt to remove one of theatoms from the S, group and so isolate another form ofniobium(1v) compound in which two metal centres are linked bytwo bridging sulphur atoms.The compound chosen for thestudy was Nb,C14S,4tht. The reasons for the choice were firstthat the compound, unlike the parent chalcogenide halide, has adetectable S-S vibration in its i.r. spectrum. Secondly it is a wellcharacterised species having been the subject of a single-crystalX-ray study., Thus the reaction of Nb,C14S,-4tht withtriphenylphosphine was carried out. The i.r. spectrum of theinsoluble brown niobium-containing product did not show anyof the bands associated with a S-S group or triphenylphosphine.The analytical data were in accord with the product beingNb2CI,S,4tht.The i.r. spectrum of the soluble product wasconsistent with it being a mixture of triphenylphosphine andtriphenylphosphine sulphide; a strong band occured at 638 CM'in accord with the presence of the P=S bond of triphenyl-phosphine sulphide.To prove that the desired reaction had actually taken placea crystal of the niobium-containing product was studied bysingle-crystal X-ray methods. The unit cell contains four dis-crete units of Nb,C14S,4tht confirming that the desiredreaction product had been obtained, an atom having beenremoved from an S, group.Significant bond lengths and anglesare given in Table 3 and the molecule is depicted in the Figurewhich also contains the atomic numbering scheme. There is nosymmetry within the dimeric unit and the two metal atoms arelinked by two bridging sulphur atoms [Nb-S 2.350(3)-2.355(3)A] thus forming a Nb-S-Nb-S ring whose geometry is similarto that in Nb,Cl,S2*4NCMe.6 The angles within this ring [atS(1) 75.10(9), S(2) 75.14(9), Nb(1) 105.01(10), and Nb(2)1O4.75( 10)') suggest the presence of a niobium-niobiuminteraction and this is supported by the distance of separation-I--Table 3. Selected bond lengths (A) and angles (") for Nb2C1,S,4thtNb(2)-Nb( 1)-C1(3)Nb(2)-Nb( 1 )-C1(4)C1( 3)-Nb( 1 )-C1(4)Nb(2)-Nb( 1 )-S( 1)C1(3)-Nb( 1)-S( 1)C1(4)-Nb( 1)-S( 1)"2kW 1 )-W)2.868(2)2.374(3)2.372( 3)2.350(3)2.350(3)2.769( 3)2.768(3)104.19( 8)1 03.8 5( 8)151.94(11)52.53(7)98.26( 1 1 )99.49( 11)52.48(7)86.50(9)168.46( 10)14 1.5 1 (7)78.91( 10)103.52(8)103.76(8)152.68( 1 1)52.37( 7)97.89( 1 1)97.49( 1 1)52.38(7)98.99( 1 1)98.75( 1 1 )104.75(10)140.76( 7)75.1q9)C1(3)-Nb(l)-S(2) 98.44(11)C1(4)-Nb(l)-S(2) 97.74(11)S( 1 )-Nb( 1 )-S(2) 105.01 (1 0)Nb(2)-Nb( 1)-S(5) 139.01(7)C1( 3)-Nb( l)-S(5) 80.41( 10)C1(4)-Nb(l)-S(5) 79.17( 10)C1(4)-Nb(l)-S(6) 78.61( 10)S( 1)-Nb( 1 )-S(6) 165.96( 10)S(2)-Nb( 1 FS(6) 89.02( 10)WtNb(1 H 6 ) 79.48(9)Cl(l)-Nb(2)-S(3) 80.08( 10)C1(2)--Nb(2)-S(3) 77.92( 1 I)S(1)-"2kS(3) 88.4q 10)S(2)-Nb(2)-S(3) 166.79(10)Nb(l)-Nb(2)-S(4) 139.38(7)C1( l)-Nb(2)-S(4) 79.73( 10)C1(2)-Nb(2)-S(4) 80.62( 1 1)S(l)-Nb(2kS(4) 168.25(10)S(2k-Nb(2kS(4) 87.01(10)S(3tNb(2FS(4) 79.86(9)Figure.Structure of Nb2C1,S,4tht[2.868(2) A] which is within the range observed inNb,X4S,*4NCMe (X = Br or C1) [2.862(2)-2.872(3) A]. Thedistance is slightly longer than that in the parent compoun420 J. CHEM. SOC. DALTON TRANS. 1985Nb,C14S,4tht [2.844(2) A],4 where the two metal atoms arelinked by uia a sulphur atom and an S, group. In the type ofspecies under discussion it is normal for the other bonds formedto the metal centre to bend away from the metal-metal vectorand this is observed in the present structure [Cl-Nb-Nb anglesrange from 103.52(8) to 104.19(8)"].The angles involving thechlorine atoms are slightly larger than those found inNb2C1,S,-4NCMe [ 1OO.34( 17)-101.64(18)"] while the anglesinvolving the ligand atoms are comparable in both systems. Thelengths of the niobiumxhlorine bonds [2.369(3)-2.374(3) A]are intermediate between those in Nb,C14S,4tht andNb2C1,S,-4NCMe.6ConclusionsIt has been shown that the reaction of NbX, (X = Br or Cl)with Sb,S, (2: 1 molar ratio) in carbon disulphide media leadsto the formation of the niobium(1v) compounds Nb,X,S, (X =Br or C1) in quantitative yield. The reduction of niobium(v) toniobium(1v) occurs with concomitant oxidation of two (in aformal sense) S2- ions to yield a S,'- group. Thus it wouldappear that in these simple ternary systems two niobium(v)centres are reduced when bridged by three sulphur atoms.Asimilar bridging situation is seen in NbS, which containsniobi~rn(rv).'~ By contrast there is a three-atom oxygen bridgebetween two niobium(v) atoms in the porphyrin complex tri-p-oxobis[5,10,15,20-tetraphenylporphyrinatoniobium(v)]. 15*16Attempts to prepare analogous selenido-niobium(1v) species bythe reaction of NbX, with Sb,Se, in a 2:l molar ratio led toa complex mixture of products among which was elementalselenium. These observations are obviously related to trends inthe stabilities of oxidation states on descending Group 6B.Further investigation of trends in oxidation state stability werecarried out by treating Tax, with Sb,S, in a 2: 1 molar ratio.The products obtained were TaX,S together with unreactedSb2S3.These results reflect the greater resistance of tantalum(v)to reduction compared to niobium(v). Finally the stability ofdimeric sulphur-bridged niobium(1v) dimers is illustrated by theformation of Nb2C1,S,4tht from Nb2Cl,S,4tht by reactionwith PPh,. This retention of the dimeric nature is in contrast tothe situation with niobium(rv) chloride, which althoughexhibiting metal-metal bonding in the binary compound,becomes monomeric on complex formation.ExperimentalAll preparations were carried out using in all-glass vacuum line.Nujol or hexachlorobutadiene mulls of the various compoundswere made in a dry-box fitted with a recycling system in whichnitrogen was pumped over molecular sieves and a heated de-oxygenating catalyst.Preparation of Nb2X,S, (X = Br or Cl).+a) In carbondisulphide.The pentahalide NbX, (5 g) was quickly tippedunder a stream of dry nitrogen into an ampoule (previouslyweighed) which contained a magnetic follower. The ampoulewas rapidly evacuated and then filled with dry nitrogen and re-weighed. A quantity of antimony(rI1) sulphide required to givea slight excess of pentahalide above the desired 2: 1 stoicheio-metry was taken and heated to 150 "C overnight while beingpumped. The sulphide was allowed to cool and quickly pouredonto the pentahalide in the ampoule. The ampoule was cooledto liquid nitrogen temperature, dry carbon disulphide (40 cm3)was distilled onto the sulphide and the ampoule sealed. Themixture was stirred and kept at 50 "C for 10 d.The ampoule wasopened under dry nitrogen and the product isolated by vacuumline filtration. The insoluble sulphidohalide product waswashed with fresh quantities of dry carbon disulphide toremove the antimony(r11) halide also produced in the reaction.The chloride, Nb,Cl,S,, was also prepared in dichloromethanebut in an attempted reaction to prepare the analogous bromidea halogen exchange reaction took place.(b) A sealed tube reaction. The chloride Nb,C14S, wasprepared by heating (1 10 "C) niobium(v) chloride ( 5 g) andantimony(Ir1) sulphide (2: 1 molar ratio) in a sealed evacuatedsublimation tube for 2 d. The antimony(II1) chloride wassublimed out of the reaction mixture by shaking all the reactionproducts to one end of the sealed tube and maintaining this endof the tube at 110°C while the other end was at roomtemperature.Attempts to prepare the bromide by reactions insealed tubes lead to incomplete reaction.Typical analyses (Found: Nb, 43.2; C1, 33.8. Nb2Cl,S,requires Nb, 43.8; C1, 33.5%. Found: Nb, 30.6; Br, 53.5.Nb2Br,S, requires Nb, 30.9; Br, 53.2%).Preparation of' Co-ordination Compounds.-Reactions werecarried out in sealed ampoules identical to those used for thepreparation of the chalcogenide halides. The reactions ofNb2X,S3 (X = Br or Cl) (2 g) with the liquid ligands (dms, tht,and methyl cyanide) were carried out in a large excess of neatligand (30 cm3) while the reactions with the solid ligand bptewere carried out in a 1 : 1 molar stoicheiometry with carbondisulphide (40 cm3) as solvent.The ligands showed differentreactivity towards the chalogenide halides, thus while with dmsthe reactions were complete on stirring the reactants for 24 h atroom temperature, it was necessary to heat the reactants to50 "C for a period of 7 d to faciliate complete reaction with thtand MeCN. The reactions with bpte took 4 weeks at 50 "C to goto completion. All the products were insoluble in the reactionmedia. Very small amounts of materials were obtained onevaporation of the filtrates. The colour and i.r. spectra of thetrace soluble products were identical to those of the relatedinsoluble products.Table 4. Atomic co-ordinates ( x lo3) with estimated standarddeviations in parentheses for Nb2C1,S,*4thtX1 918(0)3 105(0)3 981(1)2 690(1)1 029( 1)2 333(1)2 383( 1)2 631(1)3 866(1)4 lOl(1)947(1)1134(l)3 329(7)3 383(9)4 003(8)4 207(7)4 414(5)4 138(9)3 976( 13)3 719(7)568(6)856( 10)1072(8)1359(8)1653(7)1550(9)898(8)789(6)Y1166(1)59q 1)727(2)182(3)1 Oll(2)1 585(3)- 535(2)2 29q2)- 1 179(3)1536(3)218(2)2 907(2)- 2 298( 10)- 3 079( 12)-2 968(11)- 1 814(10)2 724(10)3 679( 13)3 431(14)2 300(11)-92q11)- 1 890(12)- 1 688(13)- 613( 11)4 054(9)4 866(13)4 711(12)3 577(10)Z4 254(1)5 780(1)4 569(3)7 567(3)5 439(3)2 467(3)4 571(3)5 472( 3)6 53q3)7 3 17(3)2 668(3)3 521(3)6 773(12)5 842( 16)5 334(16)5 305(14)6 625(13)7 143(22)8 263( 16)8 422( 12)3 324(12)2 843( 19)1711(17)1698(12)3 238( 13)4 110(18)4 588( 17)4 724(14J.CHEM. SOC. DALTON TRANS. 1985 42 1Reaction of Nb2C1,S,4tht with Tripheny1phosphine.-Tri-phenylphosphine and Nb,C1,S3*4tht (3 : 1 molar ratio) wereplaced with toluene (50 cm') in an ampoule indentical to thoseused for the preparation of the chalogenide halides. The mixturewas kept at 50 "C and stirred for three months during whichperiod the colour of the insoluble material changed from greento brown. The insoluble material was isolated by filtration andcrystals of Nb2C1,S,4tht suitable for single-crystal X-rayinvestigation obtained by recrystallisation from CH,Cl, usingthe double-ampoule technique. The i.r. spectrum of the solidobtained by evaporation of the solvent contained a band at 638cm-', the position of the P=S stretch in SPPh,.Crystal Structure Determination of Nb2C1,S2~4tht.-Crystaldata. C16H32C14Nb,S6, M = 744.2, monoclinic,Q = 19.958(11), b = 12.616(8), c = 11.530(10) A, p = 97.0(1)",U = 2 881.6 A3, 2 = 4, F(oO0) = 1 496, D, = 2.03 g ~ m - ~ ,h = 0.7107 A, p(Mo-Ka) = 15.6 cm-', space group P2,/n fromsystematic absences OkO, k = 2n + 1, hOl, h + 1 = 2n + 1.Intensity data were collected on a Stoe STADI2 diffracto-meter using variable width o scans. Background counts were 20s and a scan rate of 0.0333" s-' was applied to a width of (1.5 +sin p/tan 8).5 054 Independent reflections were measured with28 < 50". 2 741 Data with I > 3 4 0 were used in subsequentcalculations.The positions of the Nb atoms were obtained from aPatterson function and the remaining non-hydrogen atomsfrom Fourier maps.The hydrogen atoms were placed in tetra-hedral positions and those in the same ligand given a common(refined) thermal parameter. Non-hydrogen atoms were givenanisotropic thermal parameters and the structure was refinedby full-matrix least squares. The final R value was 0.053 (R'0.057).Calculations were done at the University of ManchesterRegional Computing Centre using SHELX 76 with scatteringfactors taken from ref, 18. Atomic co-ordinates are given inTable 4.AcknowledgementsWe thank the S.E.R.C. for support of this work and Mr. A. W.Johans for his assistance with the crystallographic investig-ations.References1 J. L. Templeton, W. C. Dorman, J. C. Clardy, and R. E. McCarley,2 F. A. Cotton and W. T. Hall, Znorg. Chem., 1981, 20, 1285.3 F. A. Cotton and R. C. Najjar, Inorg. Chem., 1981,20, 2716.4 M. G. B. Drew, D. A. Rice, and D. M. Williams, J. Chem. SOC., Dalton5 G. W. A. Fowles, R. J. Hobson, D. A. Rice, and K. J. Shanton, J .6 A. J. Benton, M. G. B. Drew, R. J. Hobson, and D. A. Rice, J. Chem.7 H. F. Franzen, W. Holne, and H. G. von Schnering, 2. Anorg. Allg.8 M. G. B. Drew, D. A. Rice, and D. M. Williams, J. Chem. Soc., Dalton9 C. Perrin-Billot, A. Perrin, and J. Prigent, Chem. Commun., 1970,676.10 C. Perrin, A. Perrin, and J. Prigent, Buff. SOC. Chim. (Fr.), 1972,8,3086.11 J. Rijnsdorp, Ph.D. Thesis, University of Groningen, The Nether-12 H. G. von Schering and W. Beckmann, 2. Anorg. Allg. Chem., 1966,13 J. Rijnsdorp, G. J. de Lange, and G. A. Wiegers J. Solid State Chem.,14 J. Rijnsdorp and F. Jellinek, J. Solid State Chem., 1978, 25, 325.15 J. F. Johnson and W. R. Scheidt, Znorg. Chem., 1978, 17, 1280.16 C. Lecomte, J. Protas, R. Guilard, B. Fliniaux, and P. Fournari, J.17 G. M. Sheldrick, SHELX 76, University of Cambridge, 1976.18 'International Tables for X-Ray Crystallography,' Kynoch Press,Znorg. Chem., 1978, 17, 1263.Trans., 1983, 2251.Chem. SOC., Chem. Commun., 1976, 552.Sue., Dalton Trans., 1981, 1304.Chem., 1983, 497, 13.Trans., 1984, 845.lands. 1978.347, 231.1979, 30, 365.Chem. SOC., Dalton Trans., 1979, 1306.Birmingham, 1974, vol. 4.Received 19th March 1984; Paper 4143

ISSN:1477-9226    

DOI:10.1039/DT9850000417

出版商:RSC    

年代:1985

数据来源: RSC