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J. CHEM. SOC. DALTON TRANS. 1985 2493Kinetics and Mechanism of the Equilibration Reaction between (2,2',2''-Nitrilotriethoxy)nitrosylvanadate(l -) and Cyanide. Crystal Structures ofSodium (2,2',2"-Nitrilotriethoxy)nitrosylvanadate(1)-Sodium PerehlorateTetra hydrate and of Barium Cyano( 2,2',2''- n it ri lot riethoxy ) n it rosylvanadate( I)Pentahydrate tKarl Wieghardt * and Michael Kleine-BoymannLehrstuhl Anorganische Chemie I, Ruhr- Universitat, 0-4630 Bochum, Federal Republic of GermanyWolfgang Swiridoff, Bernhard Nuber, and Johannes WeissAnorganisch - Chemisches lnstitut der Universitat, D - 6900 Heidelberg, Federal Republic of GermanyThe reaction of triethanolamine, ammonium vanadate(v), and hydroxylamine in aqueous solution(pH 10) affords quantitatively a red nitrosyl complex (reductive nitrosylation), Na[V( NO){N-(C2H,0),}]~NaCI0,~4H20, ( I ) , which upon addition of cyanide forms a blue complex, Ba[V( NO) -(CN){N (C2H,0),}]-5H20, (2).The structures of these two compounds have been determined bysingle-crystal X-ray studies: ( I ) , monoclinic, space group P2,/a, with a = 12.234(3), b = 11.405(3),c = 12.478(4) A, = 93.56(3)", and Z = 4, R = 0.089 from 2 104 reflections; (Z), orthorhombic,space group P2,ab, with a = 10.91 8(1), b = 11.604(3), c = 12.327(3) A, and Z = 4, R = 0.047 for3 285 reflections. The complex anion of (1 ) exhibits distorted trigonal-bipyramidal co-ordination(O,N,) about the vanadium atoms with a linear {V-N-O}4 moiety. In contrast, the anion in (2) hasdistorted octahedral co-ordination (0,N2C) about the vanadium, involving the quadridentateligand, a linear V-N-0 group, and a cyanide.The rather long N-0 distances in complexes ( I ) and(2) (average 1.253 8 ) are in accord with low v(N-0) stretching frequencies at 1 490 and 1 450cm-l. The {V-NO}, moiety of (1 ) is susceptible to electrophilic attack by protons, generating mostprobably a hydroxylamidovanadium(v) species. This process is reversible; in alkaline solutions (1 )is regenerated. The kinetics of the equilibration reaction of complex (1) with cyanide have beenmeasured by stopped-flow spectrophotometry at pH 1 1 [ I = 2.0 mol dm-3 (NaCIO,)]. A rateconstant, k, = 1 .I 2 dm3 mol-l s-', for the forward step and one, k r = 0.61 s-l, for the reverse havebeen determined at 20 "C.In 1964 Hartkamp ' reported a spectrophotometric method ofhigh accuracy and good selectivity for the quantitative deter-mination of vanadium in which vanadium(v) was treatedwith hydroxylamine and various tris(2-hydroxyalky1)amines inalkaline solutions.Benes and co-workers 2 ~ 3 have shown thatthis reaction is equally well suited for quantitative determin-ations of H,NOH. Wieghardt and Quilitzsch subsequentlyrecognized that these reactions produced air-stable, highlycoloured nitrosyl complexes of vanadium(]) of the type{V-NO), according to the nomenclature of Enemark andFeltham.' The stoicheiometry of the reactions is as depicted inequation (1). This is a further example of the smooth reductiveVv + H2NOH ---+ V - N a 2 + + 3H+ (1)nitrosylation of vanadate(v) with hydroxylamine in alkalinesolution in the presence of co-ordinating ligands.6 Thus,[V(No)(cN>513-, CV(NO)(CN>614-, CV(NO)(H,NO)-(CN),I3-, and [V(NO)(H,NO)(pydca)(H20)] - (pydca =pyridine-2,6-dicarboxylate) have been prepared using thismethod.'-'' Recently, a report on the preparation of [V(NO),-(CN),], - and related dinitrosyl complexes uia reductive nitro-sylation with hydroxylamine has appeared.' 'The mechanism of reaction (1) has been investigated in somedetaiL6" It appears to involve the reversible interconversiont Supplementary data available (No.SUP 56308, 7 pp.): H-atom co-ordinates, thermal parameters. See Instructions for Authors, J . Chem.SOC., Dalton Transactions, 1985, Issue 1, pp.xvii-xix. Structure factorsare available from the editorial office.of an 0,N-co-ordinated hydroxylamidovanadate(v) species(Scheme) which undergoes an intramolecular two-electronredox reaction with concomitant deprotonation. A colourlesshydroxylamido( 1 - )vanadium(v) complex [VO(H,NO)-(pydca)(H,O)] has been characterized by X-ray diffra~tion.'~.'The susceptibility of the {V-NO}4 moiety to electrophilicattack by protons, generating a hydroxylamido( 1 - )vanad-ium(v) complex, has also been demonstrated when 2,2',2"-nitrilotris(2-propanol) is a quadridentate ligand.,.'We here describe the preparation, via reductive nitrosylationof vanadate(v) with H2NOH, and the crystal structures ofsodium (2,2',2"-nitrilotriethoxy)nitrosylvanadate(1~sodiumperchlorate tetrahydrate, (l), and of barium cyano(2,2',2"-nitrilotriethoxy)nitrosylvanadate(r) pentahydrate, (2).Theequilibration kinetics of the reaction of complex (1) withcyanide to give (2) have also been studied.Results and DiscussionThe reaction of ammonium vanadate(v), triethanolamine, andhydroxylamine in alkaline solution at 60 "C yields a deep redsolution, from which upon addition of solid sodium perchloratered crystals of Na[V(NO){N(C,H,0)3)]~NaC104~4H,0, (l),are obtained in good yield. The i.r. spectrum exhibits an intenseband at 1490 cm-', which is assigned to the stretching fre-quency of co-ordinated nitrosyl. This value is exceptionally lowfor a linear M-N-0 moiety (see below) and suggests that thenitrosyl group should be susceptible to electrophilic attack.',Aqueous solutions of complex (1) are stable in the presence ofoxygen for at least 24 h in the range pH 8.8-11, but in acidicsolutions under argon (pH 7-6.0) a colour change from red t2494 J.CHEM. SOC. DALTON TRANS. 1985Scheme. L = N(C,H,O),'-0 0400 500 600 700 800hlnmFigure 1. Electronic spectra of complex (1) (-, 2 x lo-' rnol dm-'in 1W" rnol dm-' NaOH) and (2) (. . . a, 2 x lO-' mol dm-' in 2 rnoldm-3 NaCN) at 20 "C (4cm cell)yellow is observed. This colour change is reversible; re-adjustment of such solutions to pH 11 restores the original redsolution. From concentrated solutions of complex (1) at pH 6(HClO,) a greenish yellow material was precipitated at 0 "Cupon addition of sodium perchlorate.At room temperature thismaterial decomposed rapidly with evolution of NO, even in thesolid state. Elemental analyses were not very reproducible butconfirmed the ratio V:N to be 1:2. In the i.r. spectrum of thismaterial no band due to co-ordinated nitrosyl (or co-ordinatedHNO 5 , was detected. The yellow precipitate reacts withgaseous ammonia whereupon the colour changes to red. The i.r.spectrum of this material again exhibited the original v(N0)frequency of complex (1). Because of its rapid decomposition,even in the solid state, we have not been able to characterize thismaterial further. We propose that the yellow material containshydroxylamide( 1 -), H2N0 -, and the ligand 2,2',2"-nitrilo-triethoxy co-ordinated to a vanadium(v) centre.Similarresults have been reported for an analogous system contain-ing the ligand 2,2',2"-nitrilotris(2-propoxy), '' corroboratingthe proposed mechanism for the reductive nitrosylation ofvanadate(v) with hydroxylamine (Scheme).6When alkaline, aqueous solutions of complex (1) are treatedwith a large excess of sodium cyanide a colour change from redTable 1. Pseudo-first-order rate constants for the reaction of complex(1) (2 x lO-' rnol dm-3) with CN- at I = 2.0 rnol dm-' (NaCIO,)W"C [CN -]/mol dm-' k0bs.lS-l10 0.20 0.3050.50 0.430.70 0.531 .oo 0.6220300.200.500.701 .oo0.200.400.601 .oo0.881.301.571.692.42.73.154.3Table 2. Summary of kinetic data for the reaction of complex (1) withCN- [I = 2.0 mol dm-3 (NaClO,)]eCl"c k,/dm3 mol-' s-l k,/s-'10 0.4 1 0.2220 1.12 0.6 130 2.38 1.91AHf$ = 60 f 4 kJ mol-', ASf$ = -38 f 12 J K-' mol-', AHr$ =75 f 4 kJ mol-', AS,* = +8 12 J K-' mol-'to blue is observed.Addition of barium chloride initiates theslow precipitation of blue crystals of Ba[V(NO)(CN)(N(C,-H,0)3)J*5H20, (2). In the i.r. spectrum NO and C=Nstretching frequencies are observed at 1450 and 2 100 cm-',respectively. The v(N0) wavenumber is 40 cm-' less than thatof complex (1). The electronic spectra of (1) and (2) in thevisible region are quite different (Figure 1); .most remarkable isthe difference in intensity of the absorption maxima. The cyano-ligand in complex (2) is substitution labile and in alkalinesolutions (pH 10) equilibrium (2) is rapidly established.Theequilibrium constant K ( = k,/k,) has been measured by spectro-photometry to be 8 f 2 dm3 mol-' at 20 "C (I = 2.0 moldm-3).(1) + CN-Reaction (2) was followed by stopped-flow spectrophoto-metry by mixing solutions of complex (1) (PH 10) with solutionsof sodium cyanide in large excess, I = 2.0 mol dm-3 (NaClO,).The decrease in absorption at the 510 nm peak of complex (1)was used to monitor the equilibration. Pseudo-first-order rateconstants, kobs., for the equilibration reaction are summarized inTable 1. Figure 2 shows the dependence of kobs. on [CN- J. Therate equation is as in (3) where k, is the rate constant for theformation of complex (2) and k, that for its dissociation.Numerical values of k , and k, were evaluated (Table 2) from theslopes and intercepts in Figure 2 using a least-squares fittingroutine.From the temperature dependence, log k against 1/ T,the respective activation parameters (Table 2) were calculatedJ. CHEM. SOC. DALTON TRANS. 1985 2495/ 30.C- Iv) \u i 2010.2 0.4 0.6 0-8 1-0[CN-1 l m o l d m 3Figure 2. Dependence of pseudo-first-order rate constants, kobs., on[CN-I for the reaction of complex (1) with cyanideThe agreement between the spectrophotometrically determinedequilibrium constant and the value obtained from kinetic data(k,/k, = 1.8 0.5 dm3 mol-’) is poor due to the relative largeuncertainty in the determination of k, (intercept, Figure 2).In the solid state the vanadium centre of complex (1) is in atrigonal-bipyramidal environment of the quadridentate ligand2,2’,2’’-nitrilotriethoxy and a co-ordinated nitrosyl (see below).Thus it is co-ordinatively and electronically (14-electronspecies) unsaturated; the addition reaction of (1) with cyanideleads then to an octahedral 16-electron species which is stillco-ordinatively and electronically unsaturated, consideringsuch known seven-co-ordinate species as [V(NO)(CN),I4-.Since the absorption spectrum of complex (1) does not changebetween pH 8.8 and 11 we assume that (1) has the samestructure in the solid state and in solution.[The diffuse-reflectance spectrum of (1) also exhibits a maximum at 510 nm.]Interestingly, the entropies of activation support the assignmentof an addition mechanism for the reaction of complex (1) withCN- (a negative value is observed), whereas the reversereaction is very likely a dissociative process (a small AS,$ isobserved).Compound (1) gave red plates which were not ideal forsingle-crystal X-ray structure determination but even so thiswas carried out and the structure refined to R = 0.089.Complex (2) gave better crystals, the structure of which wasdetermined and refined to R = 0.047.Atomic co-ordinates andselected bond parameters for (1) are given in Tables 3 and 4,those for (2) in Tables 5 and 6. Their molecular structures areshown in Figures 3 and 4 respectively.Crystals of complex (1) consist of sodium cations, thecomplex anion [V(NO){ N(C2H40)3}] -, ClO,-, and water ofcrystallization. The vanadium centre is in a distorted trigonal-bipyramidal environment; the nitrogen atoms of the quadri-dentate ligand and of the co-ordinated nitrosyl are in axialpositions, whereas three oxygens are in equatorial positions.This is to our knowledge the first {V-NO}4 type complex withc (22C(31)Figure 3.Structure of the anion in complex (I), [V(NO){N(C,H,-0)3}I-Figure 4. Structure of the anion in complex (2), [V(NO)(CN){N(C,-H4O)3 >I -I II II --Dl + - 1 I+II 0.40 ‘0-25’Figure 5. Schematic representation of a part of complex (I)co-ordination number five; [V(NO)(CN),]3 - l 6 is six-co-ordinate (octahedral) and [V(NO)(CN)6]4- as well as[V(NO)(H2N0)(pydca)(H2O)] - l o (pentagonal bipyramidal)are seven-co-ordinate 18-electron species.The N-0 bond distance of the nitrosyl group is rather long[1.254(9) A] and the V-N(2) bond length [1.696(7) A] indicatesa double bond.The V-N-0 system is linear. The bonding of thenitrosyl in complex (1) may therefore be described as V=N=O.In contrast, V-N(l) is quite long [2.184(7) A], indicating aconsiderable trans influence of the nitrosyl group. The sum ofthe three 0-V-0 angles is 354.7’ and the vanadium centre isdisplaced by 0.25 8, from the plane defined by the oxygen donoratoms (Figure 5). Atom N(l) is displaced by 0.40 8, from theplane defined by the three carbon atoms bound to it [C(12)2496 J. CHEM. SOC. DALTON TRANS. 1985Table 3. Atom co-ordinates ( x lo4) for Na[V(NO)(N(C,H40),}]~NaC104~4H,0, (1)Atom X Y Z Atom X2 233(1)946(5)2 129(6)1510(6)2 789(6)3 185(5)119(8)565( 13)3 170(10)2 363( 13)1859(11)1 198(16)-3 193(1)- 4 025(6)- 1 552(2)-3 264(7)-3 130(7)- 3 070(6)-4 127(11)-4 055(16)-4 447(12)- 3 678( 15)- 1 185(9)-2 051(11)- 2 096( 1)-1 810(5)-2 338(5)-3 739(5)133(5)- 2 654(8)-3 718(10)-3 798(9)- 4 402( 10)- 8 17(5)- 3 437(9)-4 018(11)4 056(3)8 519(3)2 886(11)4 398(10)4 718(12)4 050( 12)280(5)-4 942(3)-2 031(6)-3 201(6)5 210(6)3 342(5)Y- 2 773(3)5 997(4)6 453(4)6 864( 12)7 849( 11)6 273(14)6 508(6)5 037(6)6 219(7)- 2 070( 13)-4 303(6)-4 loO(6)Z3 104(2)774( 3)625(3)2 868(11)2 252(10)3 460( 12)3 996( 12)215(5)1577(6)- 863(5)- 1 177(6)- 2 700(5)Table 4.Selected bond parameters (lengths in A, angles in ") forNa[V(NO){ N(C,H40),}]~NaCI04~4H,0, (1)1.892(7)1.899(7)1.899(6)2.184(7)1.696(7)1.42( 1)1.43( 1)1.254(9)1.45( 1)1.47(2)1.49(2)1.44(2)1.47(2)I .45(2)1.47(2)O(lFV-O(2)0(2kV-O( 3)O(2)-V-N( 1)O( 1 )-V-N(2)0(3)-V-N(2)O( 1)-V-0(3)O( l)-V-N( 1)0(3)-V-N(1)0(2tV-N(2)N(l)-V-N(2)V-N( l t C ( 12)V-N(1 jC(32)V-N(2)-0( 2 1)V-N( 1)-C(22)115.2(3)12 1.1(3)82.2( 1)97.7(3)97.3(3)118.4(3)82.2(3)82.4( 3)98.2(3)179.6(3)1 06.3 (6)105.8(7)178.9(7)106.5( 7)C(22), C(32)]. Thus N(l) is sp3-hybridized, in contrast to thestructure of P(N(C2H40)3)S'7 where the nitrogen is in atrigonal-planar environment of the corresponding carbonatoms (sp').The conformation of the quadridentate ligand incomplex (1) is very similar to that of free 2,2'2"-nitrilotriethanolin the solid state. l 8Crystals of complex (2) consist of barium ions, the complexdianion [V(NO)(CN){N(C,H40)3}]2 -, and water of crystal-lization. The vanadium centre is in a distorted octahedralenvironment of a quadridentate, chelating ligand, a co-ordin-ated nitrosyl and a cyano-group. The {V-N-O}, moiety islinear and the corresponding V-N and N-0 bond distances arevery similar to those in complex (l), indicative of V=N=O. TheV-N bond of the chelating ligand is also trans with respect tothe nitrosyl group and within experimental error identical tothat observed in (1). The V-0 bond distances are somewhatlonger than in complex (l), most probably due to stericcrowding in going from five- to six-co-ordination.The cyano-group is weakly bound to vanadium; the V-C bond distance[2.172(6) A] is in excellent agreement with those in [V(NO)-(CN)J3- (2.17 A).'6 The bond angles 0(2)-V-0(5) and0(5)-V-0(6) are 95.1(3) and 93.0(3)", respectively. They areconsiderably smaller than those in complex (l), in agreementwith a distorted trigonal-planar arrangement of the oxygendonor atoms in (1) and distorted square planar (03C) in (2).The structures of complexes (1) and (2) clearly show that theaddition of cyanide to (1) may be accomplished by a smallamount of compression of the 0-V-0 bond angles in (1).ExperimentalPreparations.-Na[V(NO){ N(C,H,0)3}]~NaC104~4H,0,(1).This was prepared by a modification of the proceduredescribed by Hartkamp.' Ammonium vanadate(v) (1.2 g),triethanolamine (1.6 g), hydroxylammonium chloride (1.3 g),and sodium hydroxide (2 g) were dissolved in water (70 cm3) at60 "C with stirring. To the deep red solution benzene (200 cm3)was added and the volume was reduced to 50 cm3 by evapora-tion at 90 "C. Sodium perchlorate (10 g) was added and thesolution was allowed to stand at room temperature for 12 h,after which the red crystals of complex (1) were filtered off (yield3.2 g, 70%) (Found: C, 16.4; H, 4.6; N, 6.5; V, 11.4; ClO,, 22.0.C,H,,N,Na,O,,V requires C, 16.2; H, 4.5; N, 6.3; V, 11.45;ClO,, 22.4%). 1.r. (KBr disc): 1490vs cm-', v(N0). Electronicspectrum: A,.(H,O) 51 1 nm ( E 264 dm3 mol-' cm-').Ba[V(NO)(CN){N(C,H,0)3}]-5H,0, (2). Ammoniumvanadate(v) (1.2 g), triethanolamine (1.6 g), hydroxyl-ammonium chloride (1.3 g) and sodium hydroxide (3.0 g) weredissolved in water (50 cm3) at 60 "C. To the deep red solutionwere added sodium cyanide (8 g) and barium chloride (2 g)whereupon a deep blue solution was obtained which wasallowed to stand under a nitrogen atmosphere for 6 d. Bluecrystals were filtered off and air-dried (yield 2.5 g, 50%) (Found:C, 17.6; H, 4.7; N, 9.0. C,H,,BaN,O,V requires C, 17.5; H, 4.6;N, 8.8%). 1.r. (KBr disc): 2 1 0 0 s (CN) and 1450s cm-' (NO).Electronic spectrum: h,,,, (4 mol dm-3 KCN): 659 nm (E 29dm3 mol-' cm-').Reaction of Complex (1) with Protons.-An aqueous solution(50 cm3) of complex (1) (2 g) and NaClO, (10 g) was cooled to0 "C under argon.Perchloric acid (1 mol dm-3) was addeddropwise with stirring and cooling until the pH was 6, duringwhich time the colour changed from red to greenish yellow. Agreenish yellow material precipitated, which was rapidlyfiltered off (yield: 0.5 g) (Found: C, 20.7; H, 5.8; N, 7.6; ClO,,14.5. [{V(H,N0)[N(C,H40),])~0H]C10,~7H20 (tentativeformula) requires C, 20.55; H, 6.2; N, 8.0; ClO,, 14.2%).Spectrophotometric Determination of the Equilibrium Con-stant.-Compound (1) was dissolved in aqueous solutions ofKCN [0.05-1.0, I = 2.0 mol dm-3 (NaClO,)] and theabsorption at 510 and 660 nm measured at 20 "C. The molarabsorption coefficients of (l), c l , and (2), E , , at these wave-lengths were determined from a 0.001 mol dm-3 KOH solutioncontaining (1) and 4 mol dm-3 KCN containing (2).Forequilibrium (1) the expression (4) can be derived. A plot of E , -E,,,,~.)-~/(E, - E,)-' us. [CN-I-' was linear; K was determinedas 8 f 2 dm3 mol-' from the slope, using a least-squaresprocedure.Kinetic Measurements.-The kinetics of the equilibrationreaction between complex (1) and CN- were measured bJ. CHEM. SOC. DALTON TRANS. 1985 2497Table 5. Atom co-ordinates ( x lo4) for Ba[V(NO)(CN){N(C,H40),)1.5H2O, (2)X5 0 0 02 833(1)2 838(5)1 133(4)3 077(5)2 876(6)2 666(5)4 61 8(4)5 734(6)6 777(7)8 118(8)Y4 282( 1)635( 1)59 l(4)975(4)2 493( 5)634(4)607(4)4 025(6)3 676(6)6 420( 5 )- 1 028(3)i560( 1)2 234( 1)860(4)2 464(4)2 207(4)4 006(4)2 488(4)2 483(4)3 561(5)4 313(5)3 497(5)V-N( 1 ) 1.695(5) V-O( 5) 1.963(4)v-O( 2) 1.919(4) V-0(6) 1.973(5)V-C( 1 1) 2.172(6) N( 1)-O( 1) 1.25 1 (7)V-N(4) 2.185(5) C( 1 1)-N( 1 I ) 1.150(8)N( 1 tV-0(2)N( 1 )-V-C( 1 1)N( 1)-V-N(4)N( 1 )-V-O( 5)N( l)-V-0(6)0(2FV-c( 1 1)0(2)-V-N(4)0(2)-V-0(5)0(2)-V-0(6)99.0(3)90.8(3)176.9(4)9733)98.7(3)85.2(3)82.7(3)95.1(3)159.4(5)C( 1 l)-V-N(4)C( 1 1 )-V-O( 5)C(ll)-V-O(6)N(4)-V-0( 5)N(4)-V-0(6)O( 5)-V-0(6)V-C( 1 1)-N( 11)V-N( 1 )-O( 1)90.7(3)17 1.8( 5)84.1(3)80.9(2)79.8(3)93 .O( 3)176.0(6)178.0(7)X7 770(8)10 036( 10)9 056(7)8 189(6)7 848(5)5 212(5)2 866(7)3 174(6)693(5)62 l(6)Y5 580(5)4 265(5)3 821(6)1 525(5)4 420(4)6 343(4)5 823(4)8 024(4)6 241(4)3 328(6)z4 388(5)3 568(5)4 309(5)2 134(5)1 91 l(4)2 837(5)530(4)1 579(5)637(4)- 155(3)Fourier syntheses revealed the positions of all non-hydrogenatoms.Idealized positions of the H atoms bound to C atoms ofthe ligand were calculated [on the basis of d(C-H) 0.97 8, andsp3-hybridized C atoms] and included in the refinement cycleswith a fixed isotropic thermal parameter. No hydrogens werelocated for molecules of water of crystallization from finalFourier difference maps and were not included. The full-matrixleast-squares refinements were carried out with anisotropicthermal parameters for all non-hydrogen atoms [except 0atoms of C10,- anions in (l), which were refined with isotropicthermal parameters] and with unit weights, and the final Rfactors were 0.089 for (1) and 0.047 for (2).All computations were made on a NOVA 3 (General Data)computer.stopped-flow spectrophotometry (the instrument was interfacedto a PET 4001 Commodore computer for data acquisition andanalysis).The reaction was followed at 510 nm using pseudo-first-order conditions with [CN-] in large excess over complex(1) (2 x lC3 mol dmW3) and I = 2.0 mol dmP3 (NaClO,). Allsolutions were adjusted to pH 10 with NaOH.Pseudo-first-order rate constants were calculated by using aleast-squares program ' where the absorption at the beginningand after the completed reaction were treated as variables.Semilogarithmic plots of In (A, - A , ) were linear for at leastfour half-lives.The reproducibility of replicate runs was betterthan 8% for all reactions.X-Ray Structure Determinations.-Crystal data. C,H,,N,-Na,O,,V, (1). M = 444.6, monoclinic, a = 12.234(3), b =11.405(3), c = 12.478(4) A, p = 93.56(3)", U = 1737.6(8) A3,space group P2,la, Z = 4, D, = 1.699 g cm-3, p(Mo-K,) =8.1 1 cm-', F(0o0) = 91 1.8.C,H,,BaN309V, (2). M = 480.6, orthorhombic, a =space group P2,ab, Z = 4, I>, = 2.06 g cmP3, p(Mo-K,) = 28.4cm-'.Data collection.-A Siemens-Stoe AED I1 automatic four-circle diffractometer was used with graphite-monochromatedMo-K, radiation (h = 0.71069 A) and the 8-20 scan mode;2 104 unique reflections were measured for compound ( 1 ) and3 285 for compound (2) with I 3 2.5o(I) (3 d 20 < 70") andthese were used in the structure solutions and refinements.Empirical absorption and Lorentz polarization correctionswere applied.Structure solutions and refinement.The structures were solvedand refined using the SHELXTL program system.20 Thepositions of the V atoms of compounds (1) and (2) and of the Baatoms of (2) were located from Patterson syntheses. Subsequent10.918(1), b = 11.604(3), c = 12.327(3) A, U = 1 561.7(9) A3,AcknowledgementsFinancial support of this work by the Deutsche Forschungs-gemeinschaft and the Fonds der Chemischen Industrie is grate-fully acknowledged.References1 H. Hartkamp, 2. Anal. Chem., 1964, 202, 12.2 R. Benesand J. Novak, Collect. Czech. Chem. Commun., 1971,36,180.3 R. Benes, J. Novak, and Z. Sulcek, Collect. Czech. Chem. Commun.,4 K. Wieghardt and U. Quilitzsch, 2. Anorg. Allg. Chem., 1979,457,75.5 J. H. Enemark and R. D. Feltham, Coord. Chem. Ret.., 1974,13,339;6 K. Wieghardt, 'Advances in Inorganic and Bioinorganic Mechan-7 W. P. Griffith, J. Lewis, and G. Wilkinson, J. Chem. Soc., 1959, 872.8 A. Miiller, P. Werle, E. Diemann, and P. Aymonino, Chem. Ber.,9 U. Quilitzsch and K. Wieghardt, 2. Naturforsch., Teil B, 1979,34,640.10 K. Wieghardt, U. Quilitzsch, B. Nuber, and J. Weiss, Angew. Chem.,11 R. Bhattacharyya, P. S. Roy, and A. K. Dasmahapatra, J.12 K. Wieghardt and U. Quilitzsch, 2. Naturforsch., Teil B, 1981,36,683.13 B. Nuber and J. Weiss, Acta Crystallogr., Sect. B, 1981, 37, 947.14 F. Bottomley, W. V. Brooks, S. G. Clarkson, and S. B. Tong, J . Chem.15 R. D. Wilson and J. A. Ibers, Znorg. Chem., 1979, 18, 337.16 S. Jagner and N. G. Vannerberg, Acta Chem. Scund., 1970,6, 1988.17 J. C. Clardy, D. S. Milbrath, and J. G. Verkade, J. Am. Chem. Soc.,18 D. Brodalla and D. Mootz, .4ngew). Chem., 1981, 93, 824; Angew.19 D. F. DeTar, Comput. Chem., 1978, 2, 99.20 G. M. Sheldrick, SHELXTL, University of Gottingen, revision 3,1972, 37, 11 18.J. Am. Chem. Soc., 1974, 96, 5003.isms,' ed. A. G. Sykes, Academic Press, 1984, vol. 3, p. 248.1972, 105, 2419.1978, 90, 381; Angew. Chem., Inr. Ed. Engl., 1978, 17, 351.Organomet. Chem., 1984, 267, 293.Soc., Chem. Cnmmun., 1973, 919.1977,9!4, 631.Chem., int. Ed. Engl., 1981, 20, 791.July 1981.Received 19th February 1985; Paper 5128

ISSN:1477-9226    

DOI:10.1039/DT9850002493

出版商:RSC    

年代:1985

数据来源: RSC