Organometallics 1995, 14, 1850-1854
1850
Synthesis and Reaction Behavior of the Novel Mono(a-alkynyl)titanocene Chloride C(175-C5H2SiMe3)SiMe2]2Ti(C1) (CCSiMe3) H. Lang,* S. Blau, H. Pritzkow, and L. Zsolnai Ruprecht-Karls-Universitat Heidelberg, Anorganisch-ChemischesInstitut, I m Neuenheimer Feld 270, 0-69120 Heidelberg, Germany Received November 28, 1994@ The reaction of [(q5-C5H2SiMe3)SiMe2]2TiC12 (1)with 1 equiv of LiCCSiMe3 (2) yields the (3). 3 can novel mono(odkyny1)titanocene chloride [(q5-CsH2SiMe3)SiMe212Ti(Cl)(CCSiMe3) be used as a n organometallic chelating ligand for the stabilization of monomeric [CuXl entities [X = C1, Br, 02CMe1, yielding ([(q5-C5H2SiMe3)SiMe212Ti(C1)(CCSiMe3)}CuX [5a,X = C1; 5b,X = Br; 5c,X = 02CMeI. The X-ray structure analyses of 3 and 5a are reported. Crystals of 3 are orthorhombic, space group Pna21, with a = 20.22(2) b = 10.9_49(8) c = 29.53(3) V = 6537(9) Hi3, and 2 = 8; crystals Of 5x3 are triclinic, space group P1 with a = 11.195(3) b = 11.502(3) c = 14.788(4) a = 96.27(2)", B = 110.62(2)", y = 100.90(2)", V = 1717.7(8) A3, and 2 = 2.
A, A,
A,
A,
Introduction While mono(a-alkyny1)zirconocene compounds are well studied,l the corresponding titanocene species are known t o exchange ligands in solution to yield titanocene dichlorides and bis(alkynyl)titanocenes.2 Recently, we have shown that the latter can successfully be used as organometallic chelating ligand (organometallic n-tweezers) for the stabilization of low-valent metal carbonyl building blocks M(C0) (M = Ni, Col3 and various Fe(II),4C U ( I ) , and ~ , ~ Ag(II6fragments, whereas titanocene dichlorides neither interact with Ni(C0)dnor with [MXI aggregates (M = Cu, Ag; X = singly bonded ligand). Here, we describe the synthesis of the first stable mono(a-alkynylltitanocene chloride [(y5-C5H2SiMe3)SiMezlzTi(Cl)(C=CSiMes)(3)and its reaction with [CuXl (X= C1, Br, 02CMe);the solid state structures of 3 and { [(y5-C5H$3iMe3)SiMe212Ti(Cl)(C=CSiMe3)}CuC1 (5a)are discussed. Results and Discussion The doubly MezSi-bridged titanocene dichloride [(y5CsH2SiMe3)SiMe232TiC12 ( l I 7 reacts at 25 "C in Et20 with equimolar amounts of LiC=CSiMes (2)to form the mono[o-(trimethylsilyl)ethynyl]titanocenechloride [(y5@
A,
A,
CsH2SiMe3)SiMe212Ti(Cl)(C=CSiMe3)(3) in 97% yield. .SiMe.
-.
.
Ti
...ct SiMe,
SiMe,
3
1
Extraction of the crude material with n-pentane and evaporation of the solvent affords an orange residue, which can be crystallized from n-pentane at -30 "C. Crystals of 3 are remarkably stable toward air for several months. As in the solid state, 3 is stable in solution; the formation of [(y5-CsH2SiMe3)SiMe212TiC12 (1) and [(y5-C5H2SiMe3)SiMe212Ti(C=CSiMe3)2 is not observed. Addition of 3 to a suspension of the copper(1) compounds [CuXl(4a,X = C1; 4b, X = Br; 4c, X = OzCMe), in a 1:l molar ratio, leads to the formation of the complexes { [(y5-C5H2SiMe3)SiMe212Ti(C1)(C=CSiMe3)}CuX [5a, X = C1; 5b, X = Br; 5c, X = 02CMel in 8590% yield. Compounds 5a-c feature a monomeric CuX
Abstract published in Advance ACS Abstracts, March 1, 1995.
(1)Erker, G . ;Fromberg, W.; Benn, R.; Mynott, R.; Angermund, K.; Kriiger, C. Organometallics 1989,8, 911.
(2) Lang, H.; Seyferth, D. Z. Naturforsch. 1990,45b,212. For the synthesis of related (r15-C5H5)2Ti(C'CSiMes)2, see also: Wood, G. L.; Knobler, C. B.; Hawthorne, M. F. Inorg. Chem. 1989,28,382. (3)Yasufuku, K.;Yamazaki, H. Bull. Chem. SOC.Jpn. 1972,45, 2664. Lang, H.; Zsolnai, L. J . Organomet. Chem. 1991,406,C5. Lang, H.; Imhof, W. Chem. Ber. 1992, 125, 1307. Lang, H.; Herres, M.; Zsolnai, L. Bull. Chem. SOC.Jpn. 1993,66, 429. Lang, H.; Herres, M.; Imhof, W. J . Organomet. Chem. 1994,465, 283. (4) Lang, H.; Herres, M.; Zsolnai, L.; Fritz, M. J . Organomet. Chem. 1991,409, C7. Herres, M.; Lang, H. J . Organomet. Chem., in press. (5) Lang, H.; Kohler, K.; Blau, S. Coord. Chem. Reu., in press and literature cited therein. (6) Lang, H.; Herres, M.; Zsolnai, L. Organometallics 1993, 12, 5008. (7)Lang, H.; Blau, S.; Muth, A.; Weiss, K.; Neugebauer, U. J . Organomet. Chem., in press.
3
5
50: X = Ci 5b: X = Br
5c:
x
= o*cMe
unit, with the copper atom in an essentially trigonalplanar environment. Complexes 5a-c are soluble in benzene, THF, and acetone and can be isolated as red crystalline solids by cooling their THF solutions to -30 "C. In the solid state 5 can be handled in air for short periods of time. Compounds 5a-c are monomeric as cryoscopic molecular weight determinations in benzene have shown.
0276-733319512314-1850$09.00/0 0 1995 American Chemical Society
A Novel Mono(a-alkyny1)titanocene Chloride
Organometallics, Vol. 14, No. 4, 1995 1851 Table 1. Crystallographic Parameters for 3 and Sa
C 2 4 9
3
Sa
CsnH46CI ZSi i()Ti? 1134.76 orthorhombic Pna21 (No. 33) 20.22(2) 10.949(8) 29.53(3)
formula fw cryst syst space group
Cz~H41ClzCuSisTi 666.38 triclinic PI (No. 2) 11.195(3) a, A 11.502(3) h, A 14.788(4) c, A 96.27(2) a, deg 110.62(2) D>deg 100.90(2) 17 17.7(8) 6537(9) 1.288 1.153 gem-' Z 8 2 0.3 x 0.3 x 0.5 cryst size, mm3 0.3 x 0.2 x 0.3 Siemens R3mN diff model Siemens R3mN 1.195 abs coeff. mm-' 0.539 Mo K a (0.710 73) Mo K a (0.710 73) radiation (A,A) temp, K 200 295 scan mode w-scan w-scan I .20 scan range, deg 1.20 5.0-29.3 scan speed, deg min-I 3.6-29.3 20 range, deg 4.0-48.1 3.0-50.0 O5h513 index ranges 05h523 -135k513 -125 k 5 0 - 1 7 . 5 1 5 16 051533 6096 526 1 no. of unique data 3830 no. obsd [ I z 2a(f)] 3373 RI" 0.073 0.066 WRZ~ 0.140 0.198 (i R I - [EllFnl - lFcll/EIFnl] only for observed reflections. "wRz = [E[Fn?- Fc?)?]/Z[w(F,?)2]]".' for all reflections.
Table 2. Selected Bond Lengths (A) and Angles (deg) for 3 and Sa 3
Sa
Bond lengths Cu( I)-C( 1 I j Cu( 1)-C( 12) Cu( 1)-C1(2) Cu( I)-Cl( 1j Cu( 1)-Ti( 1) Ti(I)-C(Il) Ti( I)-Cl( I ) C(ll)-C(12)
2.10(2) 2.320(4) 1.20(2)
2 .OOO( 6) 2.104(6) 2.163(2) 2.344(2) 2.9 lO(2) 2.083(6) 2.357(2) I .216(8)
Angles
Figure 1. Molecular structures of 3 (top) and 5a (bottom), showing the atomic numbering schemes. The 'H-and 13C('H}-NMR spectra of 5a-5c remain essentially unchanged in the temperature range 200317 K, and the data are consistent with monomeric species in solution. In order to establish the solid state structure of 3 and 5a-c, an X-ray diffraction study was exemplarly carried out on single crystals of 3 and 5a (Figure 1,Tables 1-4). The CuCl moiety in 5a is cooperatively bonded t o a chloro substituent (C1(1))as well as to a CEC triple bond (C(ll)-C(l2)). The atoms Ti(l), Cu(l), C(11), (3121, C1(11, C1(2), and Si(5) form a plane (maximum atomic deviation 0.058 A)(Table 3). The copper atom possesses a trigonal-planar environment, comprisingthe CZbuilding block (C(ll)-C(l2)) and both chloro atoms (C1(1), C1(2)), and represents the first example in copper(1) chemistry for which the monomeric structure of the copper(1)moiety is brought about by one v2-coordinated Me3SiCW ligand and one +bonded chloro group (Cl-
C(1 l)-cu(l)-cl(2) C( 12)-Cu( 1)-C1(2) C1(2)-Cu( 1)-Cl( I ) Cu(l)-C(I 1)-Ti(1) C(lZ)-C(Il)-Ti(l) C(l l)-C(l2)-Si(5) C(ll)-Ti(l)-Cl(l)
176(1) 174(1) 99.8(4)
153.5(2) 119.2(2) 108.84(8) 90.9(2) 168.40j 164.2(6) 94.9(2)
(1)).As a result of the dative Cl(l)-Cu(l) bonding the Ti(l)-Cl( 1)bond is slightly lengthened from 2.320(4)A in 3 to 2.357(2) in 5a. The Cu(l)-C1(1) interatomic distance of 2.344(2)A in 5a is significantly longer than the according Cu(l)-C1(2) bond length of 2.163(2) A due to different bonding types. These data are in agreement with Cu-C1 bond distances found in compounds of type [(q5-C5H~SiMe&Ti(CM!SiMe3)21CuC1 [Cu-C1: 2.182(3) AI8 and (dppe)(CO)3Mn[(q2-CWPh)CuC11[dppe = bis(dipheny1phosphino)ethanel [Cu-C1: 2.120(1) &,9J0 containing terminal copper-chloride units, and [(q5C5H5)(C0)2Fe(~z-C~CPh)CuCl12 [Cu-C1: 2.267(5)All1
A
(8)Lang, H.; Hemes, M.; Kohler, K.; Blau, S.; Weinmann, S.; Weinmann, M.; Rheinwald, G.; Zsolnai, L. J . Organomet. Chem., in press. (9)Solans, X.; Solans, J.;Miravitlles, C.; Miguel, D.; Riera, V.; RubioGonzales, J. M. Acta Crystallogr. 1986, C42, 975. (10)Bruce, M. I.; Abu Salah, 0. M.; Davies, R. E.; Ragharan, N. V. J . Organomet. Chem. 1974, 64, C48.
1852 Organometallics, Vol. 14,No.4,1995
Lang et al.
Table 3. Atomic Coordinates ( x lo4) and Equivalent Isotropic Displacement Parameters (A2x lo3) for 3a atom
X
v
1773(1) 4188(1) 2497(2) 4254(2) 3545(2) 961(2) 685(2) 1230(2) 2403(2) 4557(8) 3707( 16) 5 100( 13) 48 12(21) 4766( 16) 39 19(24) 53 l3(21) 5019(34) 4014(2) 3748(2) 6076(2) 2738(2) 2627(5) 2 122(6) 1515(6) I6 18(6) 2311(6) 746(6) 646(5) 803(5) 1006(6) 950(6) 2070(6) 2237(6) 3261(19) 2406(20) 1813(22) 2956( 19) 2716(23)
3347(2) -402(2) 3347(3) - 1698(4) 4204(3) 5724(3) 3769(4) 767(3) -530(4) 3830( 19) 4469( 34) 4836(26) 3808(43) 3655(38) 4486(45) 4685(42) 3209(64) 905(4) -2231(4) -758(6) 369(5) 4474( 10) 4036( 1 I ) 4500( 1 I ) 5290( 1 I ) 527% IO) 4062( 10) 3264( 11) 2068( 10) 2087( 1 1) 3324( 1 I ) l728( 13) 840( 13) -1071(41) 45(37) - 1708(42) -1572(35) -222(44) - 1400(29)
1558(15)
U?"
3145(1) 5101(1) 3754( I ) 5722(2) 2626( 1) 3319(2) 2396(1) 3994( I ) 2281(2) 5817(9) 5755( 14) 541% 10) 6358(13) 5831(14) 5992( 18) 5603( 16) 64 I O(2 I ) 4153 I ) 4350(2) 5385(2) 5917(2) 2693(4) 2405(5) 2520(4) 2894(5) 2983(4) 3384(5) 2999(4) 3156(4) 3617(4) 3739(5) 2823(5) 26 1415) 2388( 15) l658( 13) 238 1( 16) 2571(13) 1751(15) 2254( I I )
atom
v
X
3684(8) 3896( 14) 3809( 16) 3977(7) 1361(8) 288(7) 769(7) 26(8) 1948(6) 489(6) 1444(8) 3409(5 ) 3243(5) 3034(6) 3068(6) 3293(6) 4675(6) 456 l(6) 5008(7) 5392(6) 5 164(6) 444 I(7) 4558(7) 4230(7) 383X7) 3502(8) 3703(9) 5846(24) 6496(29) 6736(20) 6304(3 1) 5900( 18) 6800(28) 2 199(16) 3434( 17) 22 l3( 16) 1992(28) 3325( 19) 2509(26)
2717(16) 5628(27) 5266(3 I ) 4280( 17) 6287( 13) 6763( 12) 2474( 15) 4817( 17) - 144( 12) -264( 12) 1390(13) 304( 12) 9l3( 13) 84( 13) -1099(13) -972( 13) - 139(12) - l456( 12) - 1784(15) -78 1 ( 13) 223(13) l274( 13) 2282( 15) 25 16(12) 737(15) -2492( 17) -3690( 15) 45 l(44) -2392(53) 265(42) 902(56) - 1570(33) -9 l6(64) 1874(29) 640(35) -859(3 1) 1072(53) 1066(39) - 1304(44)
ti,,
2348(6) 2344( 1 I ) 2 152(12) 3173(7) 3837(6) 3 15318) 2007(5) 2186(6) 3777(5) 4024(6) 4558(5) 4582(4) 4985(4) 5328(5) 5127(5) 4667(5) 4390(5) 4458(5)
4802(6) 4967(6) 4684(5) 5399(4) 5555(5)
4270(4) 3553(5) 3766(6) 4645(8) 5895( 18) 5198(20) 5131(16) 5546(26) 5879( 13) 5161(21) 5889( 12) 63 13( 12) 6125(11) 5910(22) 6288( 15) 6164( 19)
(' tieq IS defined as one-third of the trace of the orthogonalized U,, tensor.
I Lp
\ Figure 2. Schematical representation of { [(75-C5HzSiMedSiMezIzTi(Cl)(CECSiMe3))CuCl (5a, left) and [(r5CsH4SiMe3)~Ti(C=CSiMe3)21CuCl~(right). [(~2-Me3SiCWSiMe~)CuC1]2 [Cu-C1: 2.279(1), 2.281(1)&,12 and [(y2-tmtch)CuC112(tmtch = 3,3,6,6-tetramethyl-l-thia-4-cycloheptyne, C1oH1&3) [Cu-C1: 2.267(21, 2.283(2) &,13 dimeric compounds, which exhibit bridging copper-chloride entities. As a result of the r2-coordination of the CEC triple bond to the copper atom the angle Cl(l)-Ti(l)-C(ll) in 3 decreases from 99.8" to 94.9(2)" in Sa. This leads to a deformation of the Ti-CW-Si unit in 5a [TiC(ll)-C(12) = 168.4(5)", C(ll)-C(l2)-Si(5) = 164.2(61'1, which is almost linear in 3 [Ti(l)-C(ll)-C(l2) = 176(1)",C(ll)-C(l2)-Si(5) = 174(1)"1. Through this de(11)Bruce, M. I.; Clark, R.; Howard, J.;Woodward, P. J. Organomet. Chem. 1972,42,C107. Abu Salah, 0. M.; Bruce, M. I. J . Chem. Soc., Dalton Trans. 1974,2302. (12) Aleksandrov, G. G.; Gol'ding, I. R.; Sterlin, S. R.; Sladkov, A. M.; Struchkov, Yu.T.; Garbuzova, I. A.; Aleksanyan, V. T. Itu. Akad. Nauk S S R , Ser. Khim. 1980,12,2679 (Engl. Transl., 1858).
formation different copper-carbon bond lengths [Cu(l)C(11) = 2.000(6) A, Cu(l)-C(12) = 2.104(6) AI are observed (Figure 2). Similar bonding situations were found in compounds of the type [(y5-CsH4SiMe&Ti(C=CSiMe&]hfX (M = Cu, Ag; X = singly bonded inorganic or organic ligand) in which the bis(alkyny1)titanocene acts as "organometallic n tweezers'' (Figure 2).3-6 The D(l)--Ti(l)-D(2) angles [D(l), D(2) = centroids of the cyclopentadienyl ligands] are thereby not influenced (Table 3). The y2-coordinationof the C W unit to a CuCl entity in 5a is additionally confirmed by IR spectroscopy: The CW-stretching vibration is shifted from 2023 cm-' in 3 to 1905 cm-' in 5a, indicating a weaker CEC bond in 5a.6 The same observation is made for 5b (1905 cm-l) and 5c (1909 cm-l), a phenomenon typical for n-bonding of alkynes t o copper(1) moieties in which the alkyne ligand is acting as a 2-electron donor.5 The OzCMe unit in 5c is bidentate bonded to the copper atom as evidenced by the difference of the asymmetric (1561 cm-') and the symmetric (1421 cm-l) OZC stretching vibration. l4 In the 13C{lH}-NMRspectra it is found that upon q2coordination of the (trimethylsily1)ethynyl ligand to the copper atom in 58-c, the resonance signals of the C, ~~
~~~
~
(13) Olbrich, F.; Schmidt, C.; Behrens, U.;Weiss, E. J . Organomet. Chem. 1991,418, 421. (14) Nakamoto, K. In/ra,rvl- and Ramal/-Spectraoflnorganic and Coordination Compound.s, 3rd cd.; Wiley Interscience: New York, 1977.
Organometallics, Vol. 14, No. 4, 1995 1853
A Novel Mono(a-alkyny1)titanocene Chloride Table 4. Atomic Coordinates ( x 104) and Equivalent Isotropic Displacement Parameters (A2x 103) for 5a' atom
X
39 I6( 1) 2204( 1) 1646(2) 4554(2 ) 2255(2) -469(2) 2570(2) 3390(2) 7 I IO(2) 1882(6) 2597(6) 1858(6) 609(6) 665(6) 987(6) 2252(6) 3 194(6) 2598(6) 1248(6) 4205 (6) 5309(6) 7306(49) 77 17(58) 7696(58) 7554(22) 7897(24) 7680(28) 3977(7) 1940(9) 1115( 10) - 1659(7) - I340(8) 4357(7) 1762(8) 5062(39) 3185(63) 2486(55) 4598(27) 4257(27) 2079( 18)
v
1052(1) 2707( I ) 603( I ) -610(2) I185(2) 3444(2) 5478(2) 2 188(2) 2934(2) 2306(5) 3511(5) 4 1440) 3304(6) 2213(5) 3656(6) 4473(5) 4025(5) 2960(5) 2752(6) 2839(5) 2694(6) 2432(82) 454 I(46) 2232(73) 3 17 l(25) 4244( 25) 1656(30) 1117(7) 1739(8) -296(7) 2020(7) 4660(7) 6034(6) 6748(6) 2382(68) 30 16(42) 613(27) 1393(25) 3358( 13) 1147(22)
UP"
2261( 1) 1893(1) 1338(1) 2294(2 ) 4261(2) 1084(I ) 2487( I ) -410(1) 3657(2) 3440(4) 3587(4) 2918(4) 2341(4) 2671(4) 725(4) 1302(4) 1051(4) 332(4) 155(4) 262 l(4) 2998(4) 4762(42) 3846(67) 2868(54) 4970( 16) 3375(20) 3295(25) 4645(5) 5364(6) 3612(7) 385(5) 1047(6) 3204(6) 2375(6) 275(37) -1490(31) -907(45) 305(15) -864( 2 1) - 1435(14)
Ueqis defined as one-third of the trace of the ortho-gonalized
U,
tensor.
and Cp atoms in the Ti-CW-Si entity (at 163.7 and 133.1 ppm in 3)are slightly shifted downfield (5a, 165.1, 134.3ppm; 5b, 167.2,135.0ppm; 5c, 167.1,134.1ppm). This is in agreement with the observation generally made by changing from noncoordinated to y2-coordinated a l k y n e ~ . ~This J ~ also results in a high-field shift of the proton signals of the (trimethylsily1)ethynyl groups in the lH-NMR spectra of 5a-c.
Experimental Section General Comments. All reactions were carried out under an atmosphere of nitrogen using standard Schlenk techniques. Tetrahydrofuran (THF) and diethyl ether (Et201 were purified by distillation from sodiumhenzophenoneketyl; n-pentane was purified by distillation from calcium hydride. Infrared spectra were obtained with a Perkin-Elmer 9830 spectrometer. 'HNMR spectra were recorded on a Bruker AC 200 spectrometer operating a t 200.132 MHz in the Fourier transform mode; I3CNMR spectra were recorded at 50.323 MHz. Chemical shifts are reported in 6 units (parts per million) downfield from tetramethylsilane with the solvent as the reference signal. FAB and E1 mass spectra were recorded on a Finnigan 8230 mass spectrometer operating in the positive-ion mode. Melting points were determined with use of analytically pure samples, which were sealed in nitrogen-purged capillaries on a Gallen-
kamp MFB 595 010 M melting point apparatus. Microanalyses were performed by the Organisch-Chemisches Institut der Universitat Heidelberg. (A) Synthesis of 3. [(r15-C5H2SiMe3)SiMezlzTiC12(1)' (1.0 g, 1.98 mmol) was added a t 25 "C in one portion to a solution of LiCCSiMe3 (2)16(0.2 g, 1.98 mmol) in 100 mL of EtzO. After the solution was stirred for 2 h the solvent was evaporated and the residue was extracted with 50 mL of n-pentane. Crystallization a t -30 "C yielded 3 (1.1g, 1.92 mmol; 97%) as a n orange-colored solid. Data for 3. Mp: 142 "C. IR (KBr): 2023 (w) [YC-C]cm-'. 'H-NMR 6 [CDCls] 0.10 (S, SiMes, 9H), 0.35 (S, SiMea, 18H), 0.48 (S, SiMe, 3H), 0.50 (S, SiMe, 3H), 0.71 (S, SiMe, 3H), 0.84 (S, SiMe, 3H), 6.71 (D, JHH = 1.4 Hz, Cp, 2H), 7.38 (D, J H H= 1.4 Hz, Cp, 2H). W{'H}-NMR: 6 [CDCl3I -5.4 (S, SiMe), -4.5 (S, SiMe), 0.1 (S, SiMe3, SiMe), 1.0 (S, SiMe), 1.9 (S, SiMes), 110.6 (S, Cp), 116.2 (S, Cp), 133.1 (S, CC-Si), 134.2 (S, Cp), 144.7 (S, Cp), 144.9 (S, Cp), 163.7 (S, CC-Ti). EI-MS [mlz (re1 int)]: 566 (loo),M+; 551 (31),M+ - Me; 493 (201,M+ - SiMe3; 478 (23), M+ - SiMer; 459 (53), M' - C1 - SiMe3; 434 (291, M+ - C1- CzSiMes; 386 (241, M+ - C1 - 2SiMes. Anal. Calcd for C25H43C1Si5Ti(567.38): C, 52.92; H, 7.64. Found: C, 52.67; H, 7.39. (B) Synthesis of 5a-c. To a solution of [(v5-C6H2SiMe3)SiMezlzTi(Cl)(CECSiMe3) (3)(150 mg, 0.26 mmol) in THF (20 mL) the appropriate [CIS], (4a, 30 mg; 4b, 43 mg; 4c, 37 mg; 0.30 mmol) was added in one portion. The suspension was stirred in the dark for 2 h a t 25 "C and afterward filtered through a pad of Celite (5.0 x 2.5 cm2;THF). On concentrating the filtrate and cooling it to -30 "C compound 5 (5a, 156 mg, 0.23 mmol, 90%; 5b, 157 mg, 0.22 mmol, 85%; 5c, 152 mg, 0.22 mmol, 85%) was obtained as a red crystalline solid. Data for 5a. Mp: 180 "C (dec). IR (KBr): 1905 (w) [vc=cI cm-'. 'H-NMR: 6 [CDC13] 0.26 (S, SiMe3, 18H),0.31 (S, SiMes, 9H), 0.49 (S, SiMe, 3H), 0.60 (S, SiMe, 3H), 0.78 (S, SiMe, 3H), 0.92 (S, SiMe, 3H), 6.43 (D, JHH = 1.2 Hz, Cp, 2H), 6.97 (D, J H H 1.2 Hz, Cp, 2H). I3C{'H}-NMR: 6 [CDCls] -5.5 (S, SiMe), -4.5 (S, SiMe), -0.2 (S, SiMes), 0.9 (S, SiMe), 1.4 (S, SiMe), 111.3 (S, Cp), 115.2 (S, Cp), 134.3 (S, CZC-Si), 135.0 (S, Cp, 140.1 (S, Cp), 141.6 (S, Cp, 2 0 , 165.1 (S, CGC-Ti, 1C). FAB-MS [mlz (re1 int)]: 666 (181, M'; 631 (100) M+ C1. Anal. Calcd for C25H43C12CuSi5Ti(666.38): C, 45.06; H, 6.50. Found: C, 45.20; H, 6.36. Data for 5b. Mp: 142 "C (dec). IR (KBr): 1905 (w) [vc=cI cm-I. 'H-NMR 6 [CDCls] 0.28 (S, SiMes, 18H),0.35 (S, SiMes, 9H), 0.52 (S, SiMe, 3H), 0.62 (S, SiMe, 3H), 0.81 (S, SiMe, 3H), 0.95 (S, SiMe, 3H), 6.46 (D,JHH = 1.2 Hz, Cp, 2H), 7.01 (D, J H H= 1.2 Hz, Cp, 2H). 13C{'H}-NMR: 6 (acetone-&) -5.4 (S, SiMe), -4.5 (S, SiMe), 0.0 (S, SiMes), 0.1 (S, SiMes), 1.5 (S, SiMe), 1.6 (S, SiMe), 112.9 (S, Cp), 116.8 (S, Cp), 135.0 (s, C=C-Si), 135.3 (S, Cp), 141.2 (S, Cp), 142.6 (s,cp), 167.2 (s, C=C-Ti). EI-MS [mlz (re1 int)]: 710 (1)M+; 566 (loo),M+ CuBr; 551 (lo), M+ - CuBr - Me; 493 (241, M+ - CuBr SiMe3; 478 (28) M' - CuBr - SiMe4;458 (40), M+ - CuBr C1 - SiMe3; 383 (35), M+ - CuBr - C2Si~Me.i. Anal. Calcd for C25H43BrC1CuSi5Ti(710.83): C, 42.24; H, 6.10. Found: C, 41.76; H, 5.86. Data for 5c. Mp: 203 "C. IR (KBr): 1909 (w) [vc-cl cm-'; 1561 (m), 1421 (m) [vcoL1cm-'. 'H-NMR: 6 (CDC13) 0.28 (S, SiMes, 18H), 0.31 (S, Me, 3H), 0.33 (S, SiMe3, 9H), 0.51 (S, SiMe, 3H), 0.62 (S, SiMe, 3H), 0.80 (S, SiMe, 3H), 0.94 (S, SiMe, 3H), 6.45 (D, JHH = 0.9 Hz, Cp, 2H), 6.99 (D, JHH = 0.9 Hz, Cp, 2H). 13C{'H}-NMR: 6 (acetone-dd -5.4 (S, SiMe), -4.5 (S, SiMe), 0.0 (S, SiMes), 1.5 (S, SiMes), 1.5 (S, SiMe), 20.5 (S, Me), 112.6 (S, Cp), 116.5 (S, Cp), 134.1 (S,C=C-Si), 135.0 (S, Cp), 141.0 (S, Cp), 142.6 (S, Cp), 167.1 (S, CZC-Ti), 171.9 (S, 02C). FAB-MS [mlz (re1 int)]: 653 (42), M+ - C1; 631 (1001, M+ - 02CMe. Anal. Calcd for C27H46ClCuO~Si5Ti (689.97): C, 47.00; H, 6.72. Found: C, 48.03; H, 6.70. ~~
(15)Wrackmeyer, B.; Horchler, K. Prog. NMR Spectrosc. 1990,22, 209.
(16) Lang, H.; Keller, H.; Imhof, W.; Martin, S. Chem. Ber. 1990, 123,417 and literature cited therein.
1854 Organometallics, Vol. 14, No. 4, 1995 X-ray Structure Determinations of 3 and 5a. The structures of compounds 3 and Sa were determined from single crystal X-ray diffraction data, which were collected using a Siemens R3mN (Nicolet Syntex) diffractometer. Crystallographic data for 3 and 5a are given in Table 1. The structures of 3 and 5a were solved by direct methods (SHELXS 8617 1. An empirical absorption correction was applied. The structures were refined by the least-squares method based on F with all measured reflections (SHELXL 9318 ). Two of the trimethylsilyl groups (C(13)-C(15); C(23)-C(25)) in 5a are disordered and were refined by two sets (site occupation factor 0.66/0.34, 0.68/0.32). The carbon atoms of the cyclopentadienyl rings (C(l)-C(lO)) in 3 were refined (17)SHELXS 86: Sheldrick, G. M. Program for Crystal Structure Determination, University of Gottingen, 1986. (18)SHELXL 93: Sheldrick, G . M. Program for Crystal Structure Determination, University of Gottingen, 1993.
Lang et al. isotropically. All other heavy atoms were refined anisotropically. The hydrogen atoms were placed in calculated positions, and their temperature factors were refined isotropically.
Acknowledgment. We are grateful to the Deutsche Forschungsgemeinschaft, the Volkswagenstiftung, and the Fonds der Chemischen Industrie for financial support. We thank Prof. Dr. G . Huttner and Dr. Th. Seitz for many discussions and Th. Jannack for carrying out the MS measurements. Supplementary Material Available: Tables of crystallographic parameters, hydrogen parameters, anisotropic thermal parameters, and bond distances and angles (17 pages). Ordering information is given on any current masthead page. OM9409027
