摘要:

1974 a165Distorted Dodecahedra1 Co-ordination in the Crystal Structure of Iso-quinolinium Tetrakis[4,4,4-.trif luoro-I -( 2-thienyl) butane-) ,3-dionato]-cerium( 111)By Andrew T. McPhail * and Pui-Suen Wong Tschang, Paul M. Gross Chemical Laboratory, Duke University,The crystal structure of isoquinolinium tetrakis[4,4,4-trifluoro-l-(2-thienyl) butane-l,3-dionato]cerium(111) hasbeen established by three-dimensional X-ray analysis and the molecular parameters refined by full-matrix least-squares calculations to R 0.1 28 over 5325 observed reflections from photographic data. The crystals are mono-clinic, space group P2,lc. a = 22.76(4), b = 10.85(2), c = 20.13(4) A, p = 112.58(10)", Z = 4. Eight oxygenatomssurround the cerium atom, mean Ce-0 = 2.470 8, in a dodecahedral arrangement distorted by an N-H * - 0Durham.North Carolina 27706, U.S.A.hydrogen bond from the isoquinolinium ion.EIGHT-CO-ORDINATE metal complexes of the type MX,,where X = bidentate ligand, occur predominantly witheither square antiprismatic (82m-D,,) or dodecahedral(&2m-D,,) ~tereochernistry.l-~ The small potential energydifference between these two favoured forms makesit difficult to predict which geometry will be preferredin a particular complex and intermediate forms aresonietimes found. Previous structural studies onJ. L. Hoard and J. V. Silverton, Ivzzorg. Chem., 1963, 2, 235.S. J. Lippard, Progr. Ivzorg. Chem., 1967, 8, 109.anionic complexes of trivalent lanthanoids, M( p-di-ketone),-, have involved either spherically symmetricCs+ cations or the NH4+ ion, neither of which would beexpected to perturb significantly the co-ordinationgeometry around the lanthanoid ion. In contrast, thepresence of a lower symmetry counterion which has theE. L.Muetterties and C. M. Wright, Quart. Rev., 1967, 21,109.D. Blight and D. L. Kepert, Inwg. Chem., 1972, 7 , 1556,and references therein1166potential to associate with the atoms in the co-ordinationpolyhedron might be expected further to complicate thesituation. Accordingly, we have elucidated the crystalstructure of the isoquinolinium salt of tetrakis[4,4,4-t rifluoro- 1 - (2-t hien yl) but ane- 1,3-diona t 01 cerium ( 111) ,'Ce(ttb),]-, in order to define the geometry around thecerium(m) ion.EXPERIMENTALCrystal Data.-C,,H,,CeF,,?u'O,S,, 111 = 1 155, Mono-clinic, n = 22-76(4), b = 10.85(2), c = 20-13(4) A, p =112*58(10)", U = 4590 A'; D, = 1-66, Z = 4, D, == 1.676,F(000) = 2284, ~(CU-K,, h = 1.542 A) = 99 cm-'l.Spacegroup P2,/c (C,",) from absent spectra, Ok0 when R # 2n, lz02when I .f 2n.Crystallogmphic Measuwments.-Unit cell dimensionswere obtained from zero-level Weissenberg photographstaken with Cu-1qa radiation and precession photographstaken with Mo-K, ( A = 0.7107 A) radiation. Three-dimensional intensity data were estimated visually fromequi-inclination multiple-film Weissenberg photographs ofthe 120-101 reciprocal lattice nets taken with Cu-A',radiation. These data were corrected for spot shape,Lorentz, and polarization factors to yield 5325 independentstructure amplitudes.Xo corrections were made forabsorption or extinction. Initially the various layers ofdata were assumed t o be on a coninion scale as each hadbeen given similar exposure times. Absolute layer scaleswere established at the end of the isotropic refinement(vide infra) by correlation with the observed structureainpli tudes.Stvucture A mlysis.-The initial position for the ceriumatom was determined from the three-dimensional Pattersonmap, and approximate positions for the other non-hydrogenatoms were obtained Iron1 the cerium-phased (I? 0.36)three-dimensional I;, map. The identity of the sulphuratoms in three of the ligands w-as established on the basisof peak heights, but in thc remaining ligand two peaks ofapproximately equal height appeared in possible positions.Since the sulphur atom was consistently cis-planar withrespect to the adjacent C=O group in three ligands, wedecided to treat S(l) as a sulphur atom during the nextseries of calculations.The atomic positional and isotropicthermal parameters were then refined by full-matrix least-squares calculations from R 0.275 to R 0.155. Duringthese iterations the large structure was refined in blocks,treating 37 atoms in any one cycle and rotating the atoms inalternate cycles. At the end of this refinement the tem-perature factor for ~ ( 4 , B = 1.1 p i ~ , was significantly lessthan those of the atoms to which it was bonded, C(3),7.4 a2; C(5), 4.0 a2; while that for S(1) w-as high (7.8 Hia).These facts along with the earlier evidence from theelectron density suggested that this thienyl group wasdisordered.A similar disordering of the thienyl moietyhas been noted in 2-[( 2) -dimethylaminoethyl-2-thienyl-aminolpyridine hydr~chloride.~ Since our least-squaresprogram does not allow for the refinement of atom occu-pation factors, we assumed 507& population of each of twoorientations resulting from rotation about the C(5)-C(6)bond, and employed the average atomic scattering factor(fs + fc)/2 for both S(l) and C(4). It was possible toidentify atom (64) in the isoquinolinium ion as the nitrogenatom from its relatively low temperature factor. The5 G. R. Clark and G. J. Palenik, J . Amer. Chenz. Soc., 1972,94, 4005.J.C.S.DaltonTABLE 1Fractional atomic co-ordinatcs ( :i 104) and temperaturefactor parameters, with estimated standard deviationsin parenthesesceCS(1)C ( 2 )c: ( 5 )O(7) c (8)C(9)O(10)C ( l i )F(12)F(13)S(1B)C(18)C(l9)C(20)O(21)C(22)C(23)O(24)C(25)F(28)Y(29)('(31)C(33)C(34)( 3 3 5 )('(37)c 1 ( 3 8 )Cl(39)Y40)F( 42)S(43)C(44)C(45)C(47)O(49)::L)C ( 6 )F(14)$;;F(26)1:(27)C(30)C(32)C(36)F(41)C(46)C(48)C(60)C(51)O(52) c ( 5 3 )F(5.1)F(55)F(56)C(57)C(58)C(69)C(60)C(61)C(62)C(63)"64)X / U24 10.3 (4)3784(6)4257( 13)47 1 5 ( 1 4)4666(5)3 7 09 ( 8)3152(7)4030( 9)4101 (10)3 833 ( 1 0)32 72 (6)4288( 12)4857( 10)4352( 12)4098 ( 1 0)972(3)324( 12)--250(11)29(8\1102(8)872(9)11 90(9)067(9)1679(6)1671(6)940( I 1771 (1 1)1368(11)458(11)1035(3)(i31(11)798(7)496(13!1 1 32 (9)1477(8)1704(6)1452(10)201 l(5)157q 15)I %24( 11)1276(11)2074( 12)3466(4)4033( 15)4403(16)4321 (1 1)3771(9)3448 (7)2986( 7)367 7 ( 9)2 897 (6)3523( 12)3%0( 11)3774( 12)3037( 10)2255(13)2461 (1 1 )2687( 10)2573(8)3 3 03 (8)3144( 11)2192(9)2370(7)2653(10)2751 (10)I 70 3 (9)3333(9)Y lb709.3(8)-327(13)- 306(29)567(30)1469(11 j749(21)1 129( 18)812 (15)1769(22)2204(23)2 127( 14)2751 (27)3030 (2 3)2044 (26)3783(22)-679(7)- 1543(24)--1674(17)- 1109(25)-11-!1(20)--920(18)- I108(20)-349(131-- 1 404 (2 1 )-- 405 ( 13)-- 1613(24)-2151 (23)-- 808(22)- 2300(23)2938(8)3988 (24)5068(29)5078(17)3 7 9 6 (20):z51(18)2285( 13)3833(2 1)328 8 (20)2325( 11 )331 7(24)4010(32)5004(25)?372 (23)- 31 1 1 (8)- 4252(31)-4330(35)- 3491 (24)- 2719(20)- 1731 (1 7)- 1224( 15)- 1480( 19)- 660(20)- 521 (25)- 1420(24)- 601 (20)- 1844(28)- 1139(23)124(141538123)97(22)- 251 (18)507(18j- 1474(23)339 (2 0)1445( 15)1782(22)22 12( 22)Z / C3 1 9-6 (4)- 11 8 1 (7)- 1564( 15)- 1256(16)- 666(G)-627(10)-- 145(9)-323(8)515(11)988(12)935( 7)1718( 14)17 15 (1 2)2247(13)1823(11)1596(4)1710(14)1115(13)736(10)621 (7)475(9)308 (9)~- 402( 10)- 729(7)- 84 1 ( 1 0)-1584(13)- 1732( 12)- 2086( 12)- 1720(12)1437 (4)1629( 13)1234( 14)645 (8)759(10)602(7)365(9)-274(11)-712(10)-1-?46(18)- lBO7( 13)--1977(13)- 1483(14)- 17?(4)-- 33 ( 1 7)- G84(6)641 ( 19)1159(13)722(10)961(S)4'30 (8)I688 ( 1 0)1935(10)2749( 13)3133( 13)3028 (1 3)29B2( 12)159 7 (7)- 34 1 8 (1 4)- 3690(11)- 2 999 (9)-2030( 10)-- 3835 ( 1 2 )-2606(9)-2822(12)- 1820(8)- 2180( 11)- 2734( 11)B (:$*)t7 4 ( 3 )6.9( 7)7.4(7)6*0(2)4.1 (4)3*4(3)4.5(3)4-3(4)5-8 (6)9.8 (6)9.0(5)B.O( 1)5 .6 ( 5 )5.1 (5)2 * 8 ( 3 )3.1 (3)3*8(3)3*9(4)3.9(4).3*5((-")a-1 (a)4*6(4)4.2 (3)11 -7 (7)3*8(4)10*7(6)9*9(6)1@.2(6)6.2(1',5.1 ( 5 )6.3(6)2.5(3)3.5(3)3.7(2)4.2(4)4*2(4)3.0(2)8.0(8)11.4(7)11.8(7)11.7(7)7.2 ( 2 )7-8(8)B.5(5)4.0(1)4*6(3)3.0(3)8.7(9)2.9(!)3-6(4)4.0 (4)4*2(3)11.2(7)5*7(6)11*4(7)4.9(5)4.6(4)3.4(3)9.4(6)6.5 (6)3.8 (3)5*1(5)4.1(4)4-0(8)4.5 (4)4*7(4)t For the cerium atom an anisotropic temperature factorof the form B sin2 O / A 2 = 105[b,,h2 + b,,kP + b3J2 + b&k -b,,hZ + b2,KZ] was employed with parametersb,, b,, b,, bl, 613 b,,131(1) 523(7) 170(1) -41(8) 70(2) 16(91974In the ligandsTABLE 2(a) Interatomic distances (A)1167Bond (u1---u2js (1)-C(2)S(l)-c(5)c (3)-C( 4)C(4)-C(5)C(5)-C(6)c (8)-C(9) c (9)-0 ( 10)C( 9)-c (1 1)C( 1 1)-F( 12)S(1) * - * O(7)C ( 2)-C (3)C(6)-O(7)C (6)-C(8)C( 1 1 )-F( 13)C( 1 1)-F( 14)O(10) - - F(13)O(10) - * * F(14)Atoms1*54(3)1 *56(3)1*37(4)1 -58( 3)1*67(2)1*48(3)1-23 (2)1.46(3)1*40(3)1 a24 (3)1.55 (4)1*33(4)1 a2 7 (4)1.25(4)2.92 (2)2*84(3)2-72 (3)(n)Atoms Atoms:rz -t 14) (w + 28)1.65(3) 1.62(3)1*68(2) 1*73(2)1.35(4) 1*38(4)1-50(3) 1*58(3)1.46(3) 1*56(3)1*56(3) 1.44(3)1*20(2) 1*23(2)1-42(3) 1.41(3)1.38(3) 1.36(3)1-28(3) 1.25(2)1*49(3) 1-60(4)1*37(4) 1-32(4)1*28(4) 1-27(4)1*33(4) 1.24(4)2.82(2) 2.87(2)2*75(2) 2*72(3)2*76(2) 2*78(3)A4tonis1-73(3) 1-67 *1*71(2) 1.71 *1*30(5) 1.34 *1.45(5) 1.51 *1.48(3) 1.50 *1*48(3) 1-491-24(2) 1.231-38(3) 1.421*40(3) 1.391*28(3) 1-261-63(3) 1.541.31(4) 1.301.29(4)1.32(4)2.88(2) 2-872.84 (3)(n + 42) MeanI2.74(3)) 2*77I n the isoquinolinium ionC (57)-C (58) 1.35 (4) C (60)-C(6l) 1 -43 (3) C (63)-N(64) 1 -2 8(3)C( 57)-C( 62) 1 *38( 4) C( 60)-C( 66) 1.48( 3) N(64)-C( 65) 1 -41 (3)C(58)-C(59) 1*45(3) C(61)-C(62) 1*40(3) C(65)-C(66) 1.31(3)C (59)-C (60) 1 *3 9 (3) C( 6 1 )-C( 63) 1 -43 (3)&an C-C = 1.40- - C-N 1.35Dodecahedron parametersCe-O(7) 2.492(15)Ce-O(l0) 2.425(15)Ce-O(21) 2-480(14)Ce-O(24) 2-454(13)Type gO(10)-O(35) 3-24(2)O(10)-O(52) 2.85(2)O(21)-O(36) 2.89(2)O(7)-O(38) 2*92(2)O(7)-O(49) 2*86(2)O(2 1)-O(52) 2.93 (2)O(24)-O(38) 3*05(2)O( 24)-O(49) 3*18(2)Cc-O(35) 2-460(14) MeanCe-O(38) 2*563(12) Ce-0Ce-O(49) 2.426(16) = 2.470Ce-O(52) 2.461(14)Typc mO(7)-O(10) 2*83(2)O(21)-O(24) 2*81(2)O(35)-O(38) 2-85(2)O(49)-O(52) 2*74(2)Type bO(10)-O(38) 3*42(2)O( 10)-O(49) 3.74(2)O(21)-O(38) 4*27(2)O(21)-O(49) 3.45(2)Type aO(7)-O(24) 3.41(2) 'leanO(35)-O(52) 3*49(2) 1 zg45In the ligandsc (2)-S( 1)-c(5)S ( l)-C(2)-c(3)S( l)-C(5)-C(4)C (2)-C (3)-C (4)C (3)-C( 4)-C( 6)S(l)--C(5)-C(6)C (4)-C( 5)-C( 6)C (5)-C (6)-O( 7)C (5)-C (6)-C (8)O( 7)-C(6)-C( 8) <: (6)-0 ( 7)-CeC (6)-C (8)-C (9)C( 8)-C( 9)-0 (10)C(8)-C( 9)-C( 11)C ( 9)-O( 10)-CeC(9)-C(lI)-F(12)C( 9)-C (1 1)-F( 1 3)C( 9)-C( 1 1)-F( 14)F(l2)-C(ll)-F(13)F( 12)-C( 11)-F( 14)F( 13)-C(ll)-F( 14)0 ( 7)--<:e-O ( 10)O( lO)-C(9)-C( 11)Atoms (n)102*6(16)109.9(25)120-6(25)93.4(16)113*2(13)123.1 (1 6)123.7 (1 6)1 16*5( 17)116-4( 17)127.0 (1 8)133*7( 13)120.4(20)128*5(22)L17.8(21)113*4(20)133*6(15)112*3(23)112-4(25)110*8(24)109-9(26)101 -3 (25)109*6(26)70*1(5)(b) Interatomic angles (")Atom (n + 14) (Atoms (n +91.2 (12) 94*1(12)11 5.3 (21) 11 8-O( 21)114*0(22) 11 2-6(23)102*4( 17) 102.2 (1 7)116*8(15) 113*1(13)1 15.1 (1 4) 118-4( 15)128-0( 17) 1 2 8 q 18)115-3(16) 117.1 (17)115*6(17) 11 8.6( 18)129.1 ( 1 8) 184-2( 18)137.1 (1 3) 141*1(12)1 30.6 (2 0) I34.9(20)11 7*9(20) 114*5(21)11 1*5(19) 110*7(20)134-6( 13) 129.1 (12)115*3(22) 112*1(27)1 15.3 (23) 109-7 (27)112*6(22) 1 1 1 *5 (28)108.1 (23) 107*3(30)99*9(22) 106.8 (30)104*0(23) 110*2(31)69 * 3 (4) 69*1(4)1 1 8.5 ( 1 9) 12 1 1 (20)28) (Atoms (+z + 42)9 1 -9 ( 1 4)111.0(28)120-1(33)103*9( 23)113*0( 16)118*0(14)128-9( 18)117.0( 16)11 7.1 (16)125-9(17)138*1(13)11 7*9( 18)13 1.2(18)118*4(19)132.0( 12)115-3( 23)116*2(24)113*4(22)110-5(26)97.1(23)101 *9 (24)68.1 (6)110.1 (18)}Mean92.4 *114-8116.6 *102.8 *114.3 *117.2 *128.5 *11 6-5116.9126.6137.6119.5131.4117.2111.4132.4113.1106.369.1168In thc isoquinoliuiri ionJ.C.S.DaltonTABLE 2 (Continued)(b) Interatomic angles ( c o n t i m d )C (!8)-C( 57)-C(68) C( 6O)-C ( 6 1 )-C (63)C (07)-C(58)-C (59) 1 1 8.4 (23) C( 57)-C( 63)-C(G1)C ( 5 8)-C( 59)-C (60) C (6 1 )-C (63)-p\I (64)C (59)-C (6O)--C(6 1) C( 63)-N (64)-C (65)C( 6 l )-C (6O)-C( 66) N (64)-C (65)-C (66)C(6O)-C(Gl)-C(62) 119*1(18) C(6O)-C(66)-C(65)L 27.0 (27)1 15.4 (20)f 23.5 (1 9)1 1 7.0 (1 7)115*9(18)115.9(23)123*6( 19)122.1(18)119-3(21)121 -8 (2 1)* Omitting the distances and angles in the disorr?crcd thienyl rjiigInteriiiolecular distances .< 3.4 AO(38) * .* K(64)F(54) - - F ( 1 2 V )O(7) * * * N(64)F(40) - * - F ( 2 8 9F(26) . * * C(30nI)F(41) - * * N ( 6 4F(56) * * F(42I)C(30) - * - F(27I)F(40) - * * F(26II)F(14) - C(591)F(42) * - - C(65)2.ii72.902.932.993-043-133.133-173.203.233.26C(34) * * C(5Y)C(31) * * eF(271)S(29) * . *F(?l')O(7) * * - C(63)F(14) * * F(46II)O(24) * * * C(63)C(48) * - - C(58IV)F(42) - - N(64)(i(35) * - - C(66I)C(3.3) * * * C(601)3-2d3.293.323-333.363.363.363.363.373.39Roman numeral superscripts refer to the following transformations of the co-ordinates of Table 11 x > * - y , * + z I V x , -4 - y , 4 + zV l - - x , - + + y , * - - z I1 x , 1 -1- y , zI11 -x, -y, -2refinement process was brought to convergence at R 0.128by two more least-squares cycles during which the ceriumatom was allowed to assume anisotropic vibration para-meters.Final atomic positional and thermal parametersare given in Table 1.C(58)c (571 C(C(62) C(61) &66 c(60) 14% F t j 4 ) dF(56)FIGURE 1 Atom numbering scheme and solid stateconfiguration of C,H,N[ (C,H4F,0,S)4Ce]For all the structure factor calculations, scattering factorsfor cerium from ref.6, and carbon, oxygen, and fluorinefrom ref. 7 were used. In the least-squares calculationsCw(Fo - F,)a was minimized with weights w assigned* For details of Supplementary Publications see Notice toAuthors No. 7 in J.C.S. Dalton, 1973, Index issue.D. T. Cromer and J. T. Waber, Acta Cryst., 1966.18, 104.7 International Tables for X-Ray Crystallography, vol. 111,8 R. A. Lalancette, M. Cefola, W. C. Hamilton, and S. J . LaKynoch Press, 1962.Placa, Inovg. Chem., 1967, 6, 2127.according to the scheme .L/w = 1 for lFol < 50 and d w = 5O/IF01 for lFol > 50, and this appeared to beadequate when <wA2) was analysed in ranges of IFol.A Table of observed structure amplitudes and calculatedstructure factors has been deposited in SupplementaryPublication No.SUP 20985 (25 pp., 1 microfiche).*RESULTS AND DISCUSSIONFigure 1 shows the molecular configuration in theasymmetric crystal unit and the atom numberingscheme employed. Interatomic distances and anglesare reported in Table 2, and the results of mean planecalculations through groups of atoms are presented inTable 3,The cerium atom is co-ordinated by eight oxygenatoms with Ce-0 distances ranging from 2.425 to2-563 A, and there are significant deviations from themean of 2.470 A which is close to the correspondingM-0 distance of 2.46 A in NH,[Pr(ttb),]H,O and it isslightly longer than those of 2-40 and 2-32 A in a- andp- lo Ce(acac), (acac = acetylacetonate) and 2.323 A inCs[Y (hfac),] l1 (hfac = hexafluoroacetylacetonate).Inspite of the significant distortions from ideal geometryit is still possible to recognize that the oxygen atomssurround the cerium atom in a distorted D,, dodeca-hedral arrangement with the bidentate ligands spanningthe m edges (Hoard and Silverton notation, see Figure2) of the trapezoids 0(7)0(10)0(21)0(24) and O(35)-0(38)0(49)0(52) between which the 89.8" angle is notsignificantly different from the ideal D,, value of90°.1y12 Moreover, the angular shape parameters 8A I==38-7--48.6", mean 44-4O, and 6~ = 64.9-71-0", mean67.9", compare favourably with 0 A = 36-9', eI3 = 69.5"9 B. MatkoviC and D. Grdenik, A d a Cyyst., 1963, 16, 456.10 H. Titze, Acta Chew. Scand., 1969, 28, 399.l1 XI. J. Bennett, F.A. Cotton, P. Legzdins, and S. J. Lippard,l2 S . J . Lippard and B. J . Russ, Inovg. Cheln., 1968, 7, 1686.Inovg. Chewz., 1968, 9, 17701974 1169TABLE 3Equations of mean planes in the form * A X + BY + CZ --D = 0, and displacements (A) of some atoms from theplanes. Atoms not included in the derivation of theplane arc il alicizedPlane -4 : -0.4195X + 0-8045Y - 0.42052 + 1.878 = 0O(7) -0.28, O(10) 0.18, O(21) -0.22,0(24) 0.26, Ce0.06Plane B: -0.7836-Y - 0-5627Y - 0.28372 -+ 4.774 = 0O(35) 0-31, O(38) -0.26, O(49) 0.22, O(52) -0.34, Ce 0.08l'larl~ C : -0.3437A- -+ 0.6389Y - 0.68822 + 1.985 = 0CS (1) 0.00, C(2) 0.03, C(3) -0.04, CS(4) 0.03, C(5) -0.01,C(6) 0.01P l a ~ ~ c D : - O.28'30'Y -/- 0.9150Y - 0.28152 + 1.800 = 0S(15) 0.01, C(L6) -0.03, C(17) 0.03, C(18) -0.02, C(19) 0.01,C(20) 0.07Plane E: -0.6309X - 0.4020Y - 0.66362 -j- 3.843 = 0S(29) 0.00, C(30) 0.00, C(31) 0.00, C(32) 0.00, C(33) 0.00,C(34) 0.03P l ~ i ~ l c F : 0.7377s + 0.6657Y - 0.16072 - 3.764 = 0S(43)-0*01, C(44) 0.01, C(45) -0.01, C(46) 0.00, C(47) 0.01,C(48) -0.04Pla11e G -0.0473X 0.8560Y - 0.51472 - 0.742 = 0C(6) 0-04, O ( i ) -0.03, C(8) -0.01, C(9) -0-02, O(10) 0.02,PlarieH: -0.4'357X f 0-8171Y - 0.29442 -t 2.155 = 0CC -0.6'4, C ( 5 ) 0.10, C(11) -0.23C(20) 0.05, O(21) -0.04, C(22) -0.01, C(23) -0.03, O(24) 0.03.CC 0.01, C(19) 0.27, C(25) -0.08Plane 1 : -0-722SX - 0.4903Y - 0.48712 + 4.311 = 0C(34) 0.03, O(35) -0.01, C(36) -0.02, C(37) 0.01, O(38) 0.00,Ct: -0.14, C(33) 0.17, C(39) 0.09Plane J : 0.714GX + 0.6936Y - 0.09092 - 3.604 = 0C(48) 0.01, O(49) -0.02, C(50) 0.04, C(51) -0-08, O(52) 0.05,CP 0.62, C(47) - 0.04, C(53) - 0.25PIXIC I<: -0.730911: + 0.3088Y - 0.59772 + 2.540 = 0C(57) -0.03, C(58) 0.08, C(59) -0.02, C(60) -0.01, C(61)-0.02, C(62) -0.04, C(63) 0.06, N(64) 0.01, C(65) -0.01,* Cartesian co-ordinates (X, Y, 2) are related to the frac-tional atomic co-ordinates ( x , y , z) by the transformationIS, Y ,C(66) -0.02= [xu 3- zc cos p, yb, zc sin p]Dihedral angles (") between the planes areE / I 12.5 g:; F/J 4.7D/H 13.2calculated by Hoard and Silverton for the hard-spheremodel. Normally, complexes of D,, dodecahedral co-ordination have the order of magnitudes of the sidesg > a = m and bidentate ligands span the m edges.13However, noteworthy exceptions to this general rulehave been reported for NH,[Pr(ttb)4]H20,8 Cs[Y (hfac),] ,11and isomorphous Cs[Eu(hfac),] l4 and Cs[Am(hfac),] ,14where it has been found that g = m < a and thebidentate ligands span the g edges.We also find fromthe present study that g = m < a but here the ligandsspan the m edges. Inspection of the dodecahedra1 bparameters (Table 2) reveals significant differences amongthem, especially noteworthy is the long O(21)-O(38)distance of 4-27 A which is a consequence of N-H - . 0l3 See e.g. W. D. Bonds, juxi., R. D. Archer, and Mi. C . Harnil-ton, Inorg. Chena., 1971, 8, 1764.hydrogen bonding, N - . 0 = 2-87 A, between the iso-quinolinium ion and O(38) in the cerium co-ordinationsphere. The presence of this hydrogen bonded associ-ation weakens the Ce-O(38) interaction and increasesthe separation between these atoms to 2.563 k which issignificantly longer than the 2.470 A Ce-0 mean; aconcomitant reduction in the Ce-O(l0) = 2.426 andCe-O(49) = 2.426 distances takes place. The netresult is that the hydrogen bond causes significantdistortion from a regular D z d dodecahedral arrangementaround the cerium atom, and molecular models showclearly that in the absence of this interaction a regularconfiguration can be attained when the O(21) .O(38)distance is restored to a more normal value. It is ofnote that the hydrogen bond involves an oxygen atomin the cerium(II1) co-ordination sphere rather than oneof the electronegative peiipheral fluorine atoms which(a) Ib)FIGURE 2 The Dzd dodecahedron (a) from ref.8, and (b)in (C,H,F,O,S),Ce- with oxygen sites labelledcould act as proton acceptors. However, in additionto the hydrogen bond, the observed arrangementpositions the positively charged nitrogen atom close totwo fluorine atoms and another oxygen atom as shownin Figure 1. If we distinguish between the terminalgroups of the ligands, then the Ce(ftb),- anion has C,symmetry, for occupation of dodecahedral A and Bsites by different ends of the ligands is not conserved inthis complex. A like result was noted in the crystalstructure of NH,[Pr(ttb),]H,O where one of the ligandshas its terminal groupings reversed.The distances of the cerium atom from the P-diketoneOCCCO least-squares planes are in Table 3.From thesewe find that the cerium atom is approximately coplanarwith the other five atoms in two chelate rings,C(20)-O(24) and C(34)-0(38), whereas it is significantlydisplaced from the corresponding planes, C(6)-O( 10)and C(48)-0(52), in the other two ligands, the displace-ments corresponding to folding of 18" about the 0-0line. It has been pointed out elsewhere that while suchfolding is common it is not an essential featureI5 ofp-diketone complexes. The differences noted here maybe ascribed to differences in the intra- and inter-molecularforces exerted on each of the ligands. In the p-diketonechelate rings the mean C-C and C-0 distances, 1.41 and1-25 k, and the mean C-C-C angle 119-5", are compatiblewith the values expected for a delocalized system, andthey are in satisfactory agreement with, for example, thel4 J.H. Burns and M. D. Danford, Inorg. Chem.. 1969,8, 1780.l5 F. -4. Cotton and J. S. Wood, Inorg. Chem., 1964, 2, 2451170 J.C.S. Daltoncorresponding mean dimensions 1 ~390 (3), 1 -274( 3) A, and124.0(3)o in a number of acetylacetonate complexes.16Significant differences occur in the angles subtendedat the carbonyl carbon atoms. Adjacent to the tri-fluoromethyl group the mean C-C-0 ring angle is131.4" whereas at the other end of the ligand the meanof the C-C-0 angles is 126.6". The latter is close tothat of 124.0" in NH,[Pr(ttb),]H,O * and to the averageof 125.3(3)" in acetylacetonate complexes.16 The anglea t the trifluoromethyl group is in good agreement withthe values found in other trifluoroacetate ligands, e.g.,129.7" in Cu(hfac),H,O(dmed), l7 (dmed = NN-di-methylethylenediamine), 132.3" in Cs[Eu(hfac),] I4 andthe C(5)-C(6) bond.It is possible that the individualvariations in the other three rings reflect some furtherdisordering and that the isotropic model employed is anentirely inadequate description. In each ligand thethienyl rings are planar within the accuracy of theanalysis, and their substituent carbon atoms lie closeto the ring plane (Table 3). Dihedral angles betweenthe intraligand thienyl and the OCCCO P-diketoneplanes range from 5 to 23" and the variation is probablydue to differences in crystal packing forces.Evaluation of the torsion angles about the C-C bondsat the trifluoromethyl groups indicates that a conform-ational preference exists, for in all four cases one fluorineFIGURE 3 The crystal structure viewed in projection along the b-axisCs [Am (hf ac),] ,14 and 130.4" in N H,iPr (ht t a),] H,O.Thus substitution of the methyl group by the moreelectronegative trifluoromethyl group results in anincrease in @-diketone chelate ring angle at the carbonatoms bearing these groups.The dimensions of chemically equivalent bonds andvalency angles in the thienyl rings are in rather pooragreement and a detailed discussion is not justified.For one of these groups we assumed a 50% occupationof each of two orientations obtained by rotation about19tif3, 88, 2951.16 EL C .Lingafelter and R. L. Braun, J . Amer. Clieut. S O C . .atoni lies close to tvam-planar with respect to tlieadjacent P-diketone oxygen atom while the other twofluorine atoms are approximately equidistant from thisatom. ,4 similar result was noted in crystallineNH,[Pr(ttb),]H,O. In the trifluoromethyl groups themean dimensions are C-F = 1.30 A, C-C-F = 113.1",and 17-C-17 = 106.3". Although the mean C-F bondlength is notably shorter than the sum of the single bondcovalent radii,ls 1.41 A, it is not atypical for such bondsl7 M. A. Bush and D. E. Fenton, J . Chewz. SOC. ( A ) , 1971, 2446.L. Pauling. ' The Nature of the Chemical Bond,' 3rd edn.,Cornell liniversity Press, Ithaca, X~ew Yorlr, 19601974 1171in fluoroalkyl groups which are subject to substantiallibrational motion as in the present c ~ m p l e x . ~ ~ J ~ ~ ~ ~ Thedifferences in C-C-I; and F-C-I; angles represent aconsistent feature of trifluoromethyl groups. Corre-sponding values in some other complexes are 114 and204" in Cs[Y(hfac),],ll 112-9 and 105.9" in Cu(hfac),H,O-(dmed),,17 112 and 104" in Cu(hfac),-.19 In hfacH andliexafluoroacetic anhydride 21 the respective values are110.6 and 108.3" and 110-2 and 108-7".The atoms of the isoquinolinium cation are approxi-mately coplanar as would be expected and the meanbond lengths and angles compare f avourably withnormal values.2231. 13. Truter and B. L. Vickery, J.C.S. D a l t o ~ , 1972, 396.D-0 1%. Elder, I~iovg. Chcnt., 1969, 8, 2103.A view of the molecular packing in the crystal isshown in Figure 3 and the shorter intermolecularseparations are in Table 2. Apart from the shortNH - - - 0 hydrogen bonded separation (vide su$wa) thedistances correspond to normal van der Waals separ-ations.The extensive crystallographic calculations were carriedout on the IBM 370/165 computer located at the TriangleUniversities Computation Centre, Research Triangle Park,North Carolina. We thank Dr. F. E. Msbbs for supplyingthe crystals used for this analysis.[3/2204 RecPived, 36th Octobcv, 1973121 A. L. Andreassen, D. Zcbelman, and S. H. Bailer, J . Auzer.22 Chem. SOC. Special Publ., No. 11, 1958, and So. 18, 1965.Chem. SOL., 1971, 93, 1148, and references therein

ISSN:1477-9226    

DOI:10.1039/DT9740001165

出版商:RSC    

年代:1974

数据来源: RSC