Syntheses and Properties of Cyclopentadienyl-Substituted Imidotitanium Fluorides

Article abstract of DOI:10.1021/ic950778z

The reaction of 2 equiv of Me₃SnF with [(η⁵-C₅H₄Me)TiCl(NPh)]₂ in the presence of at least 2 equiv of pyridine affords [(η⁵-C₅H₄Me)TiF(NPh)]₂ (1) in high yield. (η⁵-C₅H₄SiMe ₃)TiCl(N-t-Bu)·py reacts quantitatively with an equimolar amount of Me₃SnF to yield [(η⁵-C₅H₄SiMe₃)TiF(N-t-Bu)] ₂ (2). The fluorides [η⁵-Cp'TiF(NSnMe₃)]₂ (Cp′ = C₅Me₄Et (3), C₅H₄Me (4)) are obtained in high yield by reaction of N(SnMe₃)₃ with (η⁵-C₅Me₄Et)TiF₃ and (η⁵-C₅H₄Me)TiF₃, respectively. Complex 3 has been characterized by X-ray diffraction. (MeAlNMes)₄ (Mes = 2,4,6-trimethylphenyl) reacts as a transamination reagent with 4 equiv of (η⁵-C₅H₄Me)₂TiF₂ to provide [(η⁵-C₅H₄Me)TiF(NMes)]₂ (5) in low yield.

Full text of DOI:10.1021/ic950778z

Inorg. Chem. 1996, 35, 741-744
741
Syntheses and Properties of Cyclopentadienyl-Substituted Imidotitanium Fluorides
Feng-Quan Liu, Axel Herzog, Herbert W. Roesky,* and Isabel Uso´n
Institute of Inorganic Chemistry, University of Go¨ttingen, Tammannstrasse 4,
D-37077 Go¨ttingen, Germany
ReceiVed June 24, 1995X
The reaction of 2 equiv of Me3SnF with [(η5-C5H4Me)TiCl(NPh)]2 in the presence of at least 2 equiv of pyridine
affords [(η5-C5H4Me)TiF(NPh)]2 (1) in high yield. (η5-C5H4SiMe3)TiCl(N-t-Bu)‚py reacts quantitatively with
an equimolar amount of Me3SnF to yield [(η5-C5H4SiMe3)TiF(N-t-Bu)]2 (2). The fluorides [η5-Cp′TiF(NSnMe3)]2
(Cp′ ) C5Me4Et (3), C5H4Me (4)) are obtained in high yield by reaction of N(SnMe3)3 with (η5-C5Me4Et)TiF3
and (η5-C5H4Me)TiF3, respectively. Complex 3 has been characterized by X-ray diffraction. (MeAlNMes)4 (Mes
) 2,4,6-trimethylphenyl) reacts as a transamination reagent with 4 equiv of (η5-C5H4Me)2TiF2 to provide [(η5-
C5H4Me)TiF(NMes)]2 (5) in low yield.
Introduction
it was shown that the oxo bridged species [η5-Cp*TiF(O)]4 (Cp*
) C5Me5) can be prepared by treatment of [η5-Cp*TiCl(O)]3
Organoimido complexes of transition metals1 have received
considerable attention in the last years, due to their presumed
role in catalytic processes such as propylene ammonoxidation,2
nitrile reduction,3 and hydrodinitrogenation catalysis.4 Com-
plexes of titanium,5 zirconium,6 and hafnium with terminal and
bridging imidochlorides,6e,f,7 are well-known but in the case of
imidometal(IV) fluoride complexes only one example is de-
scribed in the literature.5g This is due to a lack of suitable
synthetic routes for the preparation of these compounds.
Recently, we have reported on Me3SnF as an excellent
fluorinating reagent for organometallic chlorides.8 Furthermore,
with Me3SnF.8 This demonstrates that the metathesis reaction
is working in the presence of an oxo function at the metal center.
[η5-Cp*TiF(O)]4 was already accessible from the reaction of
η5-Cp*TiF3 using O(n-Bu3Sn)2.9
In order to establish synthetic routes to the isoelectronic imido
fluoride complexes of titanium(IV), we report herein an exten-
sion of this method and the properties and solid state structure
of one of these compounds.
To the best of our knowledge, iminoalanes have not previ-
ously been used as transfer reagents for the imino function.
These compounds should be particularly effective in their
reaction with organometallic fluorides due to the high fluorine
affinity toward aluminum.
* To whom correspondence should be addressed. FAX: int. + 551-
39-3373.
X Abstract published in AdVance ACS Abstracts, December 15, 1995.
(1) (a) Nugent, W. A.; Mayer, J. M. Metal-Ligand Multiple Bonds; John
Wiley and Sons: New York, 1988. (b) Nugent, W. A.; Haymore, B.
L. Coord. Chem. ReV. 1980, 31, 123. (c) Chisholm, M. H.; Rothwell,
I. P. In ComprehensiVe Coordination Chemistry; Wilkinson, G.,
Gillard, R. D., McCleverty, J. A., Eds.; Pergamon Press: Oxford,
England, 1987; Vol. 2, pp 161-188.
Results and Discussion
Me3SnF is particularly suited for the syntheses of organoti-
tanium imido fluorides in high yields. Thus, the imido fluoride
1 can be obtained by treatment of the chloride complex [(η5-
C5H4Me)TiCl(NPh)]2 with an equimolar amount of Me3SnF in
toluene. However, the reaction must be carried out in the
presence of pyridine. Otherwise no metathesis reaction takes
place. It seems to be necessary to cleave first the imido-bridged
dimer [(η5-C5H4Me)TiCl(NPh)]2 in order to generate in situ the
mononuclear pyridine adduct (η5-C5H4Me)TiCl(NPh)‚py. In
agreement with this observation, (η5-C5H4SiMe3)TiCl(N-t-
Bu)‚py can be fluorinated easily with Me3SnF, and the
coordinated pyridine is displaced. Cyclopentadienyltitanium
imido fluorides can be obtained alternatively by reaction of
cyclopentadienyltitanium trifluorides with tris(trimethylstannyl)-
(2) (a) Maatta, E. A.; Du, Y.; Rheingold, A. L. J. Chem. Soc., Chem.
Commun. 1990, 756. (b) Maatta, E. A.; Du, Y. J. Am. Chem. Soc.
1988, 110, 8249. (c) Chan, D. M.-T.; Fultz, W. C.; Nugent, W. A.;
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Nugent, W. A. Inorg. Chem. 1985, 24, 1422. (e) Grasselli, R. K.;
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therein.
(3) (a) Bakir, M.; Fanwick, P. E.; Walton, R. A. Inorg. Chem. 1988, 27,
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Chem. Soc. 1992, 114, 5462. (b) Perot, G. Catal. Today 1991, 10,
447.
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Soc. 1988, 110, 8731. (b) Cummins, C. C.; Van Duyne, G. D.;
Schaller, C. P.; Wolczanski, P. T. Organometallics 1991, 10, 164.
(c) Walsh, P. J.; Hollander, F. J.; Bergman, R. G. J. Am. Chem. Soc.
1988, 110, 8729. (d) Profilet, R. D.; Zambrano, C. H.; Fanwick, P.
E.; Nash, J. J.; Rothwell, I. P. Inorg. Chem. 1990, 29, 4362. (e) Bai,
Y.; Roesky, H. W.; Noltemeyer, M.; Witt, M. Chem. Ber. 1992, 125,
825. (f) Arney, D. J.; Bruck, M. A.; Huber, S. R.; Wigley, D. E.
Inorg. Chem. 1992, 31, 3749.
(7) Profilet, R. D.; Zambrano, C. H.; Fanwick, P. E.; Nash, J. J.; Rothwell,
I. P. Abstracts of Papers, 201st National Meeting of the American
Chemical Society: Atlanta, GA; American Chemical Society: Wash-
ington, DC, 1991; INOR 321.
(5) (a) Roesky, H. W.; Voelker, H.; Witt, M.; Noltemeyer, M. Angew.
Chem. 1990, 102, 712; Angew. Chem., Int. Ed. Engl. 1990, 29, 669.
(b) Hill, J. E.; Profilet, R. D.; Fanwick, P. E.; Rothwell, I. P. Angew.
Chem. 1990, 102, 713; Angew. Chem., Int. Ed. Engl. 1990, 29, 664.
(c) Hill, J. E.; Fanwick, P. E.; Rothwell, I. P. Inorg. Chem. 1991, 30,
1143. (d) Cummins, C. C.; Schaller, C. P.; Van Duyne, G. D.;
Wolczanski, P. T.; Chan, A. W. E.; Hoffmann, R. J. Am. Chem. Soc.
1991, 113, 2985. (e) Duchateau, R.; Williams, A. J.; Gambarotta, S.;
Chiang, M. Y. Inorg. Chem. 1991, 30, 4863. (f) Bai, Y.; Noltemeyer,
M.; Roesky, H. W. Z. Naturforsch. 1991, 46B, 1357. (g) Bai, Y.;
Roesky, H. W.; Schmidt, H.-G.; Noltemeyer, M. Z. Naturforsch. 1992,
47B, 603. (h) Winter, C. H.; Sheridan, P. H.; Lewkebandara, T. S.;
Heeg, M. J.; Proscia, J. W. J. Am. Chem. Soc. 1992, 114, 1095. (i)
Doxsee, K. M.; Farahi, J. B. J. Chem. Soc., Chem. Commun. 1990,
1452. (j) Doxsee, K. M.; Farahi, J. B.; Hope, H. J. Am. Chem. Soc.
1991, 113, 8889.
(8) Herzog, A.; Liu, F.-Q.; Roesky, H. W.; Demsar, A.; Keller K.;
Noltemeyer, M.; Pauer, F. Organometallics 1994, 13, 1251.
(9) Roesky, H. W.; Leichtweis, I.; Noltemeyer, M. Inorg. Chem. 1993,
32, 5102.
0020-1669/96/1335-0741$12.00/0 © 1996 American Chemical Society

742 Inorganic Chemistry, Vol. 35, No. 3, 1996
Liu et al.
Scheme 1
Figure 1. Structure of [(η5-C5Me4Et)TiF(NSnMe3)]2 (3). Selected
bond distances (Å) and bond angles (°). With hydrogen atoms omitted
for clarity: Ti(1)-F(1) 1.836(2), Ti(1)-N(2) 1.903(3), Ti(1)-N(1)
1.911(3), Sn(1)-N(1) 2.067(3), Ti(1)-Cp(1) 2.101(2); F(1)-Ti(1)-
N(1) 106.36(11), Ti(1)-N(2)-Ti(2) 94.35(13), Ti(1)-N(1)-Ti(2)
93.97(13), Ti(2)-N(2)-Sn(2) 126.45(14), Ti(1)-N(1)-Sn(1) 126.1-
(2), Ti(1)-N(2)-Sn(2) 126.62(14), Ti(2)-N(1)-Sn(1) 129.12(14),
N(2)-Ti(1)-N(1) 85.61(12), F(1)-Ti(1)-N(2) 106.02(11), N(2)-Ti-
(2)-N(1) 85.44(12).
Scheme 2
from 82 to 110 ppm. This indicates a relative low electron
density at the fluorine nuclei as expected for terminal bonded
fluorine. In the 19F NMR spectra of the fluoride complexes
(η5-Cp*MF3)4 (M ) Zr, Hf) the terminal bonded fluorine atoms
resonate at δ 97.5 and 41.8 ppm, respectively, while the bridging
ones have chemical shifts of at least 100 ppm to higher field
(range from -26.3 to -97.8 ppm).
The crystal structure of 3 has been determined by single-
crystal X-ray diffraction at low temperatures. The molecular
structure of 3 is shown in Figure 1, along with selected bond
distances and angles. In agreement with the result of the 19F
NMR in C6D6 solution, 3 is an imido N-bridged dimer in the
solid state as well.
Scheme 3
The Ti2N2 four-membered ring core deviates from planarity
(mean deviation from the best least-squares plane of the four
atoms involved 0.05 Å). 3 displays a cis geometry of the ligands
with respect to the Ti2N2 ring. The SnMe3 groups are slightly
bent out of the Ti2N2 plane toward the same side where the
fluoride ligands are oriented (distance between the least-squares
Ti2N2 plane and: Sn(1) ) 0.73 Å; Sn(2) ) 0.81 Å). This
minimizes the steric repulsion between the bulky C5Me4Et and
the SnMe3 groups. The structure is similar to the comparable
imido chloride complex [η5-Cp*TiCl(NSnMe3)]2 (6).6e
The Ti-N bond lengths in 3 (1.903(3)-1.912(3) Å) are
equivalent and only slightly longer than the corresponding ones
of the chloride complex 6 (mean 1.890 Å). The Ti-F bond
distances in complex 3 (mean 1.839 Å) are comparable with
those in [η5-Cp*TiF(O)]4 (1.845 Å) or in (η5-C5Me4Et)TiF3
(mean 1.830 Å).
amine. Reaction of (η5-C5Me4Et)TiF3 or (η5-C5H4Me)TiF3, with
N(SnMe3)3 in 1:1 ratio leads to the fluoride complexes [(η5-
C5Me4Et)TiF(NSnMe3)]2 (3) and [(η5-C5H4Me)TiF(NSnMe3)]2
(4), respectively. Complex 3 is accessible in refluxing THF
while for the synthesis of compound 4 boiling toluene is needed.
Finally, we were interested to determine whether organoimi-
noalanes are potentially active transfer reagents for the imido
function to organotitanium trifluorides. Despite the high fluorine
affinity of aluminum the reaction of η5-Cp*TiF3 with (MeAl-
10
NMes)4 takes 12 h at 80 °C in toluene to be completed.
Transamination takes place, Vide infra, but no defined product
could be isolated. In contrast to this result [(η5-C5H4Me)TiF-
(NMes)]2 can be obtained in 20 % yield when (η5-C5H4Me)2TiF2
is treated with (MeAlNMes)4 under the same conditions.
However, it was impossible to characterize a byproduct from
this reaction containing the remaining C5H4Me group.
The EI mass spectra of complexes 1, 2, 3, 4 and 5 indicate
on the basis of their molecular ion peaks that they are also
dimers in the gaseous state as formulated in the equations
(Schemes 1-3).
Conclusions
It has been shown that Me3SnF is a suitable fluorinating
reagent for organometallic chlorides even when an imido
function is present. This method as well as the reaction of
cyclopentadienyltitanium trifluorides with tris(trimethylstannyl)-
amine are convenient synthetic routes for preparing cyclopen-
tadienyltitanium imido fluorides in high yields. Their solid state
structures are comparable to those of the analogous chloride
complexes. They are imido N-bridged dimers possessing a
Ti2N2 four-membered ring. From the stronger electronic back
donation of fluorine rather than chlorine to the titanium center
The 19F NMR spectra of these cyclopentadienyltitanium imido
fluorides gave singlet resonances at low field in the δ range
(10) Waggoner, K. M.; Power, P. P. J. Am. Chem. Soc. 1991, 113, 3385.

Substituted Imidotitanium Fluorides
Inorganic Chemistry, Vol. 35, No. 3, 1996 743
Table 1. Crystallographic Data for 3
results a stronger basicity of the nitrogen atoms and the
complexes become more stable against bases like pyridine.
compd
3
empirical formula
fw
data collcn at T/°C
cryst dimens/mm
cryst syst
space group
a/Å
C28H52F2N2Sn2Ti2
787.90
-123(2)
0.5 × 0.4 × 0.4
monoclinic
P21/c
8.160(2)
18.749(4)
21.828(4)
99.48(3)
3293.9(12)
4
Experimental Section
General Details. All experiments were performed under a nitrogen
atmosphere by standard Schlenk techniques. Solvents (including NMR
solvents) were distilled under N2 prior to use from an appropriate drying
agent. Abbreviations: Me ) CH3, Et ) C2H5, Ph ) C6H5, t-Bu )
C(CH3)3, Mes ) 2,4,6-(CH3)3C6H2.
b/Å
c/Å
Starting Materials. Me3SnF,11 N(SnMe3)3,12 (MeAlNMes)4,10 [(η5-
C5H4Me)TiCl(NPh)]2,13 (η5-C5H4SiMe3)TiCl(N-t-Bu)‚py,5f (η5-C5Me4-
Et)TiF3,8 (η5-C5H4Me)TiF3,8 and (η5-C5H4Me)2TiF28 were prepared from
the literature procedures.
â/deg
cell vol V/Å3
formula units per cell, Z
calcd density, F/Mg m-3
Abs. coeff, µ/mm-1
F(000)
1.589
1.996
1584
7-45
Physical Measurements. 1H NMR spectra were recorded on a
Bruker WP 80 SY instrument, and 19F, 13C and 119Sn NMR spectra, on
a Bruker MSL 400 instrument, using SiMe4, CFCl3, and SnMe4,
respectively, as external standards. In all cases C6D6 was used as a
solvent. The infrared spectra were obtained using a Bio-Rad FTS-7
spectrophotometer. Mass spectra were recorded on a Varian MAT CH5
and Finnigan MAT 8230 system. Melting points (uncorrected) were
measured by using a Bu¨chi 510 apparatus. Elemental analyses were
performed by the Analytical Laboratory of the Inorganic Institute at
the Universita¨t Go¨ttingen.
Preparations. [(η5-C5H4Me)TiF(NPh)]2 (1). A mixture of [(η5-
C5H4Me)TiCl(NPh)]2 (1.50 g, 2.96 mmol) and Me3SnF (1.08 g, 5.92
mmol) in toluene (50 mL) was stirred with pyridine (0.5 mL) for 8 h
at 60 °C. All volatile contents were removed carefully in Vacuo,
yielding an orange solid. The solid was washed once with cold hexane
(20 mL). Recrystallization from toluene (20 mL) at -24 °C affords 1
as yellow-orange crystals which were filtered off and dried in Vacuo,
yield 1.26 g (2.66 mmol, 90%). Mp: 153 °C. 1H NMR (C6D6): δ
7.10-6.79 (m, 5 H, NPh), 6.14 (t, JHH ) 2.7 Hz, 2 H, C5H4Me), 5.65
(t, JHH ) 2.7 Hz, 2 H, C5H4Me), 1.96 (s, 3 H, C5H4Me). 19F NMR
(C6D6): δ 95.9 (s). Mass spectrum (EI): m/z 474 (M, 60), 395 (M -
C5H4Me, 100%). Anal. Calcd for C24H24F2N2Ti2: C, 60.79; H, 5.10;
F, 8.01; N, 5.91. Found: C, 60.7; H, 5.0; F, 8.0; N, 5.9.
measured 2θ-range/deg
no. of data measured; no. of unique data
R,a wR2b (I > 2σI)
R, wR2 (all data)
goodness of fit Sc
weight factors a, bd
refined params
restraints
4309, 4289 (Rint ) 0.04)
0.025, 0.063
0.029, 0.075
1.117
0.03, 5.31
341
0
largest diff peak, largest hole/e Å-3
+0.644, -0.833
a R ) [∑||Fo| - |Fc||]/[∑|Fo]|]. b wR2 ) [[∑w(Fo - Fc2)2]/
2
2
2
[∑w(Fo )2]]1/2
.
c S ) [[∑w(Fo2 - Fc2)2]/[∑(n - p)]]1/2
.
d w-1 ) σ2(Fo )
+ (aP)2 + bP; P ) [Fo + 2Fc2]/3.
2
SnMe3). 19F NMR (C6D6): δ 87.9 (s). 119Sn NMR (C6D6, SnMe4): δ
29.9 (s). Mass spectrum (EI): m/z 788 (M, 30), 639 (M - C5Me4Et,
100%). IR (KBr): ν 726 st, 658 st, 611 st, 583 st, 527 st, 505 st, 376
st cm-1. Anal. Calcd for C28H52F2N2Sn2Ti2: C, 42.36; H, 6.65; F,
4.82; N, 3.56. Found: C, 42.5; H, 6.6; F, 5.0; N, 3.5.
[(η5-C5H4Me)TiF(NSnMe3)]2 (4). (η5-C5H4Me)TiF3 (1.50 g, 8.15
mmol) and N(SnMe3)3 (4.12 g, 8.15 mmol) in THF (50 mL) were
treated as described for the preparation of compound 3. The extraction
procedure was carried out with toluene (20 mL) to yield 2.27 g (3.50
mmol, 86%) of yellow-orange 4. Mp: 155 °C. 1H NMR (C6D6): δ
6.41 (t, JHH ) 2.6 Hz, 4 H, C5H4Me), 5.58 (t, JHH ) 2.7 Hz, JHH ) 0.6
Hz, 4 H, C5H4Me), 2.13 (t, JHH ) 0.6 Hz, 6 H, C5H4Me). 19F NMR
(C6D6): δ 82.6 (s). Mass spectrum (EI): m/z 648 (M, 20), 165 (SnMe3,
100%). Anal. Calcd for C18H32F2N2Sn2Ti2: C, 33.38; H, 4.98; F, 5.87;
N, 4.33. Found: C, 33.1; H, 4.9; F, 5.9; N, 4.3.
[(η5-C5H4Me)TiF(NMes)]2 (5). A solution of (MeAlNMes)4 (2.01
g, 2.9 mmol) in toluene (30 mL) was added dropwise under stirring to
a solution of (η5-C5H4Me)2TiF2 (2.79 g, 11.4 mmol) in toluene (30
mL) at room temperature. The reaction mixture was heated for 10 h
at 80 °C. Afterward the volume of the solution was reduced to 20 mL
in Vacuo and the mixture was kept at -24 °C. The product crystallized
as red crystals, which were filtered off and dried in Vacuo, yield 0.96
g (1.72 mmol, 30%). Mp: 194 °C dec. 1H NMR (C6D6): δ 6.75 (s,
4 H, Mes-H), 5.49 (m, 8 H, C5H5Me), 2.75 (s, 12 H, o-Me-H), 2.13
(s, 6 H, p-Me-H), 1.66 (s, 6 H, C5H4Me-H). 19F NMR (C6D6): δ
100.1 (s). Mass spectrum (EI): m/z 559 (M, 35), 426 (M - NMes,
100%). IR (KBr): ν 1606 m, 1492 m, 1462 vst, 1378 vst, 1213 st,
1154 st, 1052 m, 853 vst, 731 st, 590 st, 535 st cm-1. Anal. Calcd
for C30H36F2N2Ti2: C, 64.53; H, 6.50; F, 6.80; N, 5.02. Found: C,
64.3; H, 6.4; F, 6.8; N, 4.8.
[(η5-C5H4SiMe3)TiF(N-t-Bu)]2 (2). A mixture of (η5-C5H4SiMe3)-
TiCl(N-t-Bu)‚py (1.04 g, 2.80 mmol) and Me3SnF (0.51 g, 2.80 mmol)
in toluene (40 mL) was stirred at 100 °C for 1 h. The solution was
allowed to cool to room temperature and all reaction volatiles were
removed in Vacuo. Recrystallization from toluene (15 mL) at -24 °C
afforded light-red crystals of 2, which were filtered off and dried in
Vacuo, yield 0.72 g (1.31 mmol, 94 %). Mp: 218 °C. 1H NMR
(C6D6): δ 6.99 (t, JHH ) 2.4 Hz, 4 H, C5H4SiMe3), 5.95 (t, 3JHH ) 2.4
Hz, 4 H, C5H4SiMe3), 1.05 (s, 18 H, CMe3), 0.31 (s, 18 H, SiMe3). 13
C
NMR (C6D6): δ 117.5 (s, C5H4SiMe3), 113.9 (s, C5H4SiMe3), 74.9 (s,
CMe3), 33.1 (s, CMe3), -0.9 (s, SiMe3). 19F NMR (C6D6): δ 109.5
(s). Mass spectrum (EI): m/z 550 (M, 20), 479 (M - N-t-Bu, 100%).
IR (CsI): ν 1180 st, 1046 st, 1012 st, 840 st, 822 st, 801 st, 643 st,
623 st, 595 st, 408 st, cm-1. Anal. Calcd for C24H44F2N2Si2Ti2: C,
53.36; H, 8.06; F, 6.90; N, 5.09. Found: C, 53.3; H, 7.8; F, 7.0; N,
5.3.
[(η5-C5Me4Et)TiF(NSnMe3)]2 (3). A mixture of (η5-C5Me4Et)TiF3
(1.27 g, 5.0 mmol) and N(SnMe3)3 (2.53 g, 5.0 mmol) in THF (50
mL) was refluxed for 8 h. When the reaction was cooled to room
temperature, THF was removed from the suspension in Vacuo. The
residue was extracted with hexane (70 mL) and filtered. 3 precipitated
as light-red crystals after reducing the volume of the filtrate to 20 mL.
The product was filtered off and dried in Vacuo, yield 1.75 g (2.22
mmol, 89%). Mp: 163.5 °C. 1H NMR (C6D6): δ 2.58 (q, 3JHH ) 7.5
Hz, 4 H, C5Me4(CH2CH3)), 2.12 (s, 12 H, C5Me4Et), 2.05 (s, 12 H,
C5Me4Et), 1.00 (t, 3JHH ) 7.4 Hz, 6 H, C5Me4(CH2CH3)), 0.40 (s, 2JSnH
) 55 Hz, 18 H, SnMe3). 13C NMR (C6D6): δ 126.1 (s, C5Me4Et),
120.7 (s, C5Me4Et), 119.9 (s, C5Me4Et), 20.8 (s, C5Me4(CH2CH3)), 15.2
(s, C5Me4(CH2CH3)), 12.5 (s, C5Me4Et), 12.2 (s, C5Me4Et), -0.3 (s,
X-ray Data Collection, Structure Solution, and Refinement of
3. Orange crystals, suitable for X-ray diffraction were grown from
THF at room temperature. A crystal was mounted on a glass fiber in
a rapidly cooled perfluoropolyether.14 Diffraction data were collected
on a Siemens-Stoe AED2 four-circle instrument at 150(2) K, with
graphite-monochromated Mo KR radiation (λ ) 0.710 73 Å), ω-2θ
scans (7° < 2θ < 45°), on-line profile fitting,15 and constant scan speed.
The structure was solved by the Patterson method SHELXS-9016 and
(11) (a) Krause, E. Ber. Dtsch. Chem. Ges. 1918, 51, 1447. (b) Johnson,
W. K. J. Org. Chem. 1960, 25, 2253. (c) Levchuk, L. E.; Sams, J.
R.; Aubke, F. Inorg. Chem. 1972, 11, 43.
(12) Lehn, W. L. J. Am. Chem. Soc. 1964, 86, 305.
(13) [(η5-C5H4Me)TiCl(NPh)]2 was made analogously to the preparations
described in ref 5g.
(14) Kottke, T.; Stalke, D. J. Appl. Crystallogr. 1993, 26, 615.
(15) Clegg, W. Acta Crystallogr. 1981, A37, 22.
(16) Sheldrick, G. M. SHELXS-90. Acta Crystallogr. 1990, A46, 467.

744 Inorganic Chemistry, Vol. 35, No. 3, 1996
Liu et al.
refined against F2 on all data by full-matrix least-squares methods with
SHELXL-93.17 All non-hydrogen atoms were refined anisotropically.
The hydrogen atoms on two methyl groups were refined disordered in
two alternative sites. All other hydrogen atoms were included in the
model at geometrically calculated positions and refined using a riding
model.
Acknowledgment. This work was supported by the Deutsche
Forschungsgemeinschaft, the BMBF, the Volkswagen-Stiftung,
and the Hoechst AG. I.U. thanks the European Union for a post-
doctoral grant (ERB CHBG 93 0338).
Supporting Information Available: Listings of crystal data, atomic
coordinates and equivalent isotropic displacement parameters for all
non-hydrogen atoms, hydrogen positional and thermal parameters,
anisotropic displacement parameters, bond distances and angles (7
pages). Ordering information is given on any current masthead
page.
Details of the crystal structure refinement are summarized in Table
1. Further details of the crystal structure investigation are available
from the Director of the Cambridge Crystallographic Data Centre,
University Chemical Laboratory, Lensfield Road, GB-Cambridge CB2
1EW, England, on quoting the full journal citation.
(17) Sheldrick, G. M. SHELXL-93. University of Go¨ttingen.
IC950778Z