Complexes of titanium and zirconium containing a tridentate linked amido-cyclopentadienyl ligand with a soft donor group: Synthesis, structure, and ethylene polymerization catalysis

Article abstract of DOI:10.1016/S0022-328X(99)00451-9

Group 4 metal complexes M(η⁵:η¹-C₅R₄SiMe ₂NCH₂CH₂SMe)Cl₂ (R=H, M=Ti; R=Me, M=Ti, Zr) containing the thioether-functionalized linked amido-cyclopentadienyl ligand were synthesized and characterized by ¹H- and ¹³C-NMR spectroscopy, mass spectrometry, and elemental analysis. The crystal structures of the complexes Ti(η⁵:η¹-C₅H₄SiMe ₂NCH₂CH₂SMe)Cl₂ and Zr(η⁵:η¹:η¹-C₅Me ₄SiMe₂NCH₂CH₂SMe)Cl₂ were determined by single-crystal X-ray diffraction studies. The titanium complex is a conventional three-legged piano-stool molecule without an intramolecular interaction between the sulfur donor group and the titanium center, whereas the zirconium complex adopts a trigonal bipyramidal structure, with the five-membered ring and the coordinating methylthio group in the apical positions. Reaction between the titanium dibenzyl Ti(η⁵:η¹-C₅Me₄ZNCH ₂CH₂SMe)(CH₂Ph)₂ (Z=SiMe₂, CH₂SiMe₂) and B(C₆F₅)₃ in C₆D₅Br resulted in the clean formation of the solvent-separated ion pair [Ti(η⁵:η¹-C₅Me₄ZNCH ₂CH₂SMe)(η²-CH₂Ph)] ⁺[(PhCH₂)B(C₆F₅)₃] ^-. The dichloro complexes M(η⁵:η¹-C₅Me₄SiMe ₂NCH₂CH₂SMe)Cl₂, when activated with methylaluminoxane, catalyzed the polymerization of ethylene with moderate activities. The phosphino-functionalized ligand C₅Me₄SiMe₂NC₆H₄(PPh ₂)-2 was also coordinated at titanium and zirconium centers; NMR spectroscopic data inferred an intramolecular metal-phosphine interaction for these M{η⁵:η¹-C₅Me₄SiMe ₂NC₆H₄(PPh₂)-2}Cl₂ complexes.

Full text of DOI:10.1016/S0022-328X(99)00451-9

www.elsevier.nl/locate/jorganchem
Journal of Organometallic Chemistry 591 (1999) 127–137
Complexes of titanium and zirconium containing a tridentate
linked amido–cyclopentadienyl ligand with a soft donor group:
synthesis, structure, and ethylene polymerization catalysis
Jun Okuda *, Thomas Eberle, Thomas P. Spaniol, Vale´rie Piquet-Faure´
Institut fu¨r Anorganische Chemie und Analytische Chemie, Johannes Gutenberg-Uni6ersita¨t, Duesberg-Weg 10–14, D-55099 Mainz, Germany
Received 17 June 1999; accepted 19 July 1999
Abstract
Group 4 metal complexes M(h5:h1-C5R4SiMe2NCH2CH2SMe)Cl2 (R=H, M=Ti; R=Me, M=Ti, Zr) containing the
thioether-functionalized linked amido–cyclopentadienyl ligand were synthesized and characterized by 1H- and 13C-NMR
spectroscopy, mass spectrometry, and elemental analysis. The crystal structures of the complexes Ti(h5:h1-
C5H4SiMe2NCH2CH2SMe)Cl2 and Zr(h5:h1:h1-C5Me4SiMe2NCH2CH2SMe)Cl2 were determined by single-crystal X-ray diffrac-
tion studies. The titanium complex is a conventional three-legged piano-stool molecule without an intramolecular interaction
between the sulfur donor group and the titanium center, whereas the zirconium complex adopts a trigonal bipyramidal structure,
with the five-membered ring and the coordinating methylthio group in the apical positions. Reaction between the titanium
dibenzyl Ti(h5:h1-C5Me4ZNCH2CH2SMe)(CH2Ph)2 (Z=SiMe2, CH2SiMe2) and B(C6F5)3 in C6D5Br resulted in the clean
formation of the solvent-separated ion pair [Ti(h5:h1-C5Me4ZNCH2CH2SMe)(h2-CH2Ph)]+[(PhCH2)B(C6F5)3]−. The dichloro
complexes M(h5:h1-C5Me4SiMe2NCH2CH2SMe)Cl2, when activated with methylaluminoxane, catalyzed the polymerization of
ethylene with moderate activities. The phosphino-functionalized ligand C5Me4SiMe2NC6H4(PPh2)-2 was also coordinated at
titanium and zirconium centers; NMR spectroscopic data inferred an intramolecular metal–phosphine interaction for these
M{h5:h1-C5Me4SiMe2NC6H4(PPh2)-2}Cl2 complexes. © 1999 Elsevier Science S.A. All rights reserved.
Keywords: Titanium; Zirconium; Linked amido–cyclopentadienyl ligand; Thioether ligand; Benzyl cation; Ethylene polymerization
center within this ligand framework [4]. The additional
1. Introduction
two-electron donor X=OMe and NMe2 could stabilize
alkyl cations of the type [M(h5:h1-C5Me4SiMe2NCH2-
In the context of homogeneous olefin polymerization
catalysis, complexes of Group 3 and 4 metals contain-
ing a linked amido–cyclopentadienyl ligand C5R%ZNR¦
[1] may be considered as hybrids of the Brintzinger-type
CH2X)CH2Ph]+ to make them more amenable to study
[5] than those of complexes containing the original
bidentate amido–cyclopentadienyl ligand C5Me4SiMe2-
4
NCMe3 [6]. Although fluxional on the NMR timescale,
ansa-metallocenes [2] and the electronically more unsat-
the coordination of the third donor group X appeared
urated and sterically more open bis(amido) chelate
to be fairly strong, resulting in a decreased activity
complexes [3]. (Scheme 1) We recently introduced a
toward ethylene polymerization. Since soft donor
potentially tridentate variation of the linked amido–cy-
groups are known to stabilize reactive Group 3 and 4
clopentadienyl ligand, C5R%SiMe2NCH2CH2X, in
which the supplementary donor ligand was designed to
4
metal centers [7–10], yet remain kinetically labile, we
decided to utilize sulfur and phosphorus donor function
temporarily protect the highly electrophilic d0-metal
groups. We report here the synthesis and characteriza-
tion of Group 4 metal complexes containing tridentate
linked amido–cyclopentadienyl ligands with SMe and
PPh2 groups.
* Corresponding author. Fax: +49-6131-395605.
E-mail address: okuda@mail.uni-mainz.de (J. Okuda)
0022-328X/99/$ - see front matter © 1999 Elsevier Science S.A. All rights reserved.
PII: S0022-328X(99)00451-9

128
J. Okuda et al. / Journal of Organometallic Chemistry 591 (1999) 127–137
Scheme 1.
2. Results and discussion
the methylthio group was observed at l 1.94 and 15.1
1
in the H- and 13C-NMR spectrum, respectively. When
2.1. Ligands with a methylthio-functionalized side chain
the ligand (C5Me4)CH2SiMe2NCH2CH2SMe, which is
prolonged by a CH2 bridge [4e], was coordinated in an
analogous manner, Ti(h5:h1-C5Me4CH2SiMe2NCH2-
CH2SMe)Cl2 (2b) was isolated (see Scheme 2).
The synthesis proceeded analogously to the one used
to prepare the methoxy- and N,N-dimethylamino-func-
tionalized complexes of titanium [4a]. Reaction between
equimolar amounts of lithium amide Li(NHCH2-
CH2SMe) and Ti(h5-C5H4SiMe2Cl)Cl3 in the presence
of triethylamine led to the complex Ti(h5:h1-
C5H4SiMe2NCH2CH2SMe)Cl2 (1) in moderate yield as
analytically pure, yellow crystals. Because the molecule
The homologous zirconium complex Zr(h5:h1-
C5Me4SiMe2NCH2CH2SMe)Cl2 (3) was prepared from
the reaction between ZrCl4(THF)2 and Li2(C5Me4-
SiMe2NCH2CH2SMe) and isolated as hexane-soluble,
colorless crystals which could be fully characterized (see
Table 1). Analogous to the methoxy and N,N%-dimethyl-
amino derivatives, Zr(h5:h1:h1-C5Me4SiMe2NCH2-
1
is Cs-symmetric, as shown by the H- and 13C-NMR
spectra, it was not possible to decide whether in-
tramolecular coordination of the thioether group was
present or not. The methylthio group appears as a
1
resonance at l 1.86 and 15.0 in the H- and 13C-NMR
spectra, respectively. Since these values do not differ
significantly from those of the free ligand, we suspect
that a dynamic situation with the equilibrium shifted
towards the from without the thioether coordination is
present. The open structure without any intramolecular
coordination was found for the crystalline state by
X-ray crystal structure analysis. Fig. 1 shows that the
methylthioethyl side chain attached to the amido–ni-
trogen atom is not interacting with the titanium center.
The side chain adopts a different conformation to that
of the methoxyethyl side chain in Ti(h5:h1-C5H4SiMe2-
NCH2CH2OMe)Cl2, but all metrical parameters
pertinent to the titanium coordination are very similar
[4b].
The tetramethylcyclopentadienyl analog Ti(h5:h1-
C5Me4SiMe2NꢀCH2CH2SMe)Cl2 (2a) could also be
prepared according to a conventional procedure. It was
isolated as yellow crystals, and was fully characterized
Fig. 1. ORTEP diagram of the molecular structure of Ti(h5:h1-
C5H4SiMe2NCH2CH2SMe)Cl2 (1). Thermal ellipsoids are drawn at
the 50% probability level. Hydrogen atoms are omitted for the sake
1
by elemental analysis, H- and 13C-NMR spectroscopy,
and mass spectrometry. A molecule with a mirror plane
was again observed in solution; its NMR spectrum
which did not change in the temperature range +80 to
−80°C suggests a similar situation as that for 1, with a
preference for the open form [4a,5]. The resonance for
,
of clarity; selected bond distances (A) and angles (°): TiꢀCp (centroid)
2.013(3), TiꢀN 1.876(3), SiꢀN 1.748(3), TiꢀCl1 2.264(2), TiꢀCl2
2.266(2), SꢀC9 1.804(4), SꢀC10 1.795(6); SiꢀNꢀC8 133.5(2),
C9ꢀSꢀC10 100.2(3), NꢀC8ꢀC9 113.4(3), C8ꢀC9ꢀS 112.5(3), TiꢀNꢀSi
108.5(1), TiꢀNꢀC8 117.9(2).

J. Okuda et al. / Journal of Organometallic Chemistry 591 (1999) 127–137
129
Scheme 2.
accommodate a long ZrꢀS bond while the other four
bonds, including the ZrꢀN bond of 2.088(2) are rela-
tively short. The sulfur atom is pyramidalized, the angle
CH2X)Cl2 (X=OMe, NMe2) (3) is a Cs-symmetric
molecule, but the resonances for the methylthio group
is somewhat low-field shifted compared to those for 2
(l 1.97 and 16.1). The resonances are invariant in the
temperature range of −80 to +80°C.
The single-crystal X-ray structure analysis of 3 re-
vealed a trigonal bipyramidal configuration, similar to
that found in the structure of Zr(h5:h1:h1-
C5Me4SiMe2NCH2CH2X)Cl2 (X=OMe, NMe2), with
,
a zirconium–sulfur distance of 2.791(1) A (Fig. 2).
This value is comparable to that found for
[Zr(h5-C5Me5)2Me(THT)]+[BPh4]− (2.730(4) A) [8]
,
(THT=tetrahydrothiophene) or [Zr(h5:h1-C5Me4-
,
CH2CH2SMe)Cl3]2 (2.767(2) A) [11a]. Similar bond
lengths between a thioether sulfur and a tetravalent
zirconium were reported in chelating bis(amido)
,
complexes: 2.805(1) A for Zr{(2,6-Me2C6H3NCH2-
i
,
CH2)2S}Me2 [9a] and 2.734(1) A for Zr{( PrN-o-
C6H4)2S}Me2 [9b]. The ZrꢀS bond in 3 is considerably
,
A in
longer than the ZrꢀO bond of 2.375(2)
Zr(h5:h1:h1-C5Me4SiMe2NCH2CH2OMe)Me2 [5], and
this results in a significant distortion of the slightly
puckered five-membered chelate ring. Although still
perfectly planar, the angles around the sp2-hybridized
amido nitrogen are different. Most notably, the
ZrꢀNꢀC12 angle with 131° is larger than the corre-
Fig. 2. ORTEP diagram of the molecular structure of Zr(h5:h1:h1-
C5Me4SiMe2NCH2CH2SMe)Cl2 (3). Thermal ellipsoids are drawn at
the 50% probability level. Hydrogen atoms are omitted for the sake
,
of clarity; selected bond distances (A) and angles (°): ZrꢀS 2.791(1),
ZrꢀCp (centroid) 2.214(3), ZrꢀN 2.088(2), SiꢀN 1.727(2), ZrꢀCl1
2.446(1), ZrꢀCl2 2.432(1), SꢀC13 1.799(3), SꢀC14 1.798(3); ZrꢀNꢀSi
107.3(1), ZrꢀNꢀC12 131.0(2), SiꢀNꢀC12 121.6(2), Cl1ꢀZrꢀCl2
108.27(4), NꢀC12ꢀC13 111.6(3), C12ꢀC13ꢀS 110.6(2), C13ꢀSꢀC14
100.6(2), C13ꢀSꢀZr 93.7(1), C14ꢀSꢀZr 107.8(1).
sponding
angle
in
Zr(h5:h1:h1-C5Me4SiMe2N-
CH2CH2OMe)Me2 (124.2(2)°) or Hf(h5:h1:h1-C5Me4-
SiMe2NCH2CH2OMe)Cl2 (124.7(5)°). This can be as-
cribed to the rather distorted chelate ring, which has to

130
J. Okuda et al. / Journal of Organometallic Chemistry 591 (1999) 127–137
(sum of the angles: 355.9° in Zr(h5:h1:h1-C5Me4-
SiMe2NCH2CH2OMe)Me2). In conclusion, all the
structural features are consistent with a somewhat
weaker interaction of the third ligating group.
Table 1
Crystallographic data for Ti(h5:h1-C5H4SiMe2NCH2CH2SMe)Cl2 (1)
and Zr(h5:h1-C5Me4SiMe2NCH2CH2SMe)Cl2 (3)
Compound
1
3
Formula
C10H17Cl2NSSiTi C14H25Cl2NSSiZr
Crystal shape
Crystal color
Crystal size (mm)
Crystal system
Space group
Prism
Yellow
Prism
White
2.2. Ethylene polymerization and benzyl cation formation
0.20×0.30×0.40 0.45×0.65×0.70
Triclinic
When the dichloro complexes were activated with
MAO under standardized conditions, ethylene was
polymerized with good activity (Table 2) to high-molec-
ular-weight linear polyethylene. As found previously, it
is striking that the zirconium complex 3 is by one order
of magnitude less active than the titanium complex 2a.
Furthermore, compared to the prototypical tert-butyl-
amido derivative Ti(h5:h1-C5Me4SiMe2NCMe3)Cl2, the
catalyst precursor 2a is less active, but shows signifi-
cantly higher activity values than the OMe- and NMe2-
functionalized analogs. This can be ascribed to the
dissimilar coordination abilities of the various third
donor groups, which effectively compete with the in-
coming ethylene molecule for coordination.
Orthorhombic
Pbca (no. 61)
(
P1 (no. 2)
Unit cell dimensions
,
a (A)
8.501(3)
9.555(5)
10.902(5)
110.20(4)
111.80(3)
91.72(4)
758.8(6)
2
0.7107 (Mo–Ka) 0.7107 (Mo–Ka)
1.108
30
7466
3029
14.954(3)
9.813(3)
25.635(9)
,
b (A)
,
c (A)
h (°)
i (°)
k (°)
3
,
V (A )
Z
3762(2)
8
,
Wavelength (A)
vlin (mm−1
)
1.034
30
9539
3524
q Scan range (°)
Reflections measured
Independent reflections
observed
As the analogous methyl cation is very sensitive, we
decided to study the solution properties of the titanium
benzyl cation, to gain some information about the
coordination sphere within the tridentate ligand system.
The dibenzyl complexes Ti(h5:h1-C5Me4ZNCH2-
CH2SMe)(CH2Ph)2 (Z=SiMe2 (4a), Z=CH2SiMe2
(4b)) were synthesized by alkylating the corresponding
[I\2|(I)]
[Rint=0.0313]
0.0563, 0.1260
[Rint=0.0460]
0.0358, 0.0753
Final R indices R1, wR2
(observed data)
Final R indices R1, wR2
(all data)
Goodness-of-fit
Parameters refined
0.0909, 0.1561
0.0777, 0.0936
1.149
214
1.063
204
0.563, −0.398
Residual density: max., min. 0.626, −1.083
dichloro
complexes
Ti(h5:h1-C5Me4ZNCH2CH2-
−3
,
Dz (e A
)
SMe)Cl2 (2) with dibenzylmagnesium. Spectroscopic
features of the complexes, isolated as red crystals, indi-
cate a structure similar to that of related dibenzyl
complexes of the general type Ti(h5:h1-C5R%-
4
at sulfur C13ꢀSꢀC14 being 100.6(2)°, similar to the
ZNR¦)(CH2Ph)2 [1b,5,12]. When the dibenzyl com-
plexes 4a and 4b were treated with one equivalent of
B(C6F5)3 in C6D5Br, NMR spectroscopy indicated
clean formation of the benzyl cations [Ti(h5:
h1 - C5Me4ZNCH2CH2SMe)(h2 - CH2Ph)]+[(PhCH2)B-
(C6F5)3]− (5a and 5b). All attempts at isolating the ion
pairs on a preparative scale have failed so far, although
they appear to be thermally stable as bromobenzene
values found for Zr{(2,6-Me2C6H3NCH2CH2)2S}Me2
(105.0(2)°)
[9a]
and
Zr{(iPrN-o-C6H4)2S}-Me2-
(103.5(1)°) [9b], as well as the titanium complex
[Ti{(OC6H2-4-Me-6tBu)2S}(OiPr)2]2 (100.8(2)°) [10f].
This coordination of the sulfur atom (sum of the an-
gles: 302.1°) contrasts to the trigonal planar methoxy
oxygen atom that can be regarded as sp2-hybridized
Table 2
Data for ethylene polymerization with methylaluminoxane-activated Ti(h5:h1-C5Me4ZNR%)Cl2 complexes a
Precatalyst
Yield (g)
Activity b
Tm (°C) c
Ref.
Ti(h5:h1-C5Me4SiMe2NtBu)Cl2
4.11
0.23
0.08
0.08
1.15
0.15
950
53
12
13
265
34
141.6
135.5
132.3
136.5
141.0
140.3
[12b]
[4e]
[5]
[5]
This work
This work
Ti(h5:h1-C5Me4SiMe2NCH2CH2NMe2)Cl2
Ti(h5:h1-C5Me4SiMe2NCH2CH2OMe)Cl2
Zr(h5:h1-C5Me4SiMe2NCH2CH2OMe)Me2
Ti(h5:h1-C5Me4SiMe2NCH2CH2SMe)Cl2 (2a)
Zr(h5:h1-C5Me4SiMe2NCH2CH2SMe)Cl2 (3)
a Polymerization conditions: titanium complex 5 mmol, methylaluminoxane 2500 mmol in 200 ml of toluene at 25°C, constant ethene pressure
3 bar (cethylene=0.432 mol l−1), reaction time 2 h.
b Activity in kg (PE) mol Ti−1×h×cethylene
c Determined by DSC (heating rate, 10 K min−1
.
)

J. Okuda et al. / Journal of Organometallic Chemistry 591 (1999) 127–137
131
Scheme 3.
solutions. That a solvent-separated ion-pair formed can
be concluded from the Dl (meta-, para-F) values of 2.8
for the anion [PhCH2B(C6F5)3]− in the 19F-NMR spec-
tra of 5a [13]. The cation contains no mirror plane, and
judged by comparison of the NMR spectroscopic data
of 5a with those of 5b, which shows resonances for the
2
benzyl group at l=2.21 and 3.32, with JHH=7.4 Hz,
1
and a 13C resonance at l=74.2, with JCH=144 Hz.
1
its H-NMR spectrum has two and four signals for the
Apparently the less basic OMe and SMe shifts the
equilibrium towards the more electrophilic dihapto-
bonded benzyl [4e,5,14].
SiMe2- and C5Me4-methyl groups, respectively. At 70°C
these signals coalesced to one SiMe2 and two C5Me4
resonances (DG‡=69 kJ mol−1), suggesting a rapid
symmetrization via a monohapto-bonded benzyl group.
At room temperature (r.t.), the benzyl group at l=
2.3. Ligands with a diphenylphosphino-functionalized
side chain
2
2.59 and 3.15 has a JHH value of 6.3 Hz in the
Because the amine H2NCH2CH2PMe2 is difficult to
prepare, we turned to the easily accessible ortho-
diphenylphosphinoaniline [15] as the precursor for the
amido side chain. Reaction of (C5Me4H)SiMe2Cl with
Li{NHC6H4(PPh2)-2} smoothly produced the cyclopen-
tadiene (C5Me4H)SiMe2NHC6H4(PPh2)-2 (31P-NMR: l
−18.4), which could be deprotonated with two equiva-
lents of n-butyllithium. The complexation reaction with
TiCl3(THF)3/PbCl2 and ZrCl4(THF)2 gave M{h5:h1-
C5Me4SiMe2NC6H4(PPh2)-2}Cl2 (M=Ti (6), Zr=(7))
as brown and colorless microcrystals, respectively.
Purification proved to be difficult because of their low
1
1H-NMR spectrum, while the JCH value of the 13C
resonance at l=72.3 is 150 Hz, suggesting a dihapto
coordination. As with the methoxy derivative [5], spe-
cies C of the various possible equilibrating species is
preferred (Scheme 3). In contrast, the N,N%-dimethyl-
amino-functionalized analog appears to contain as the
main species a monohapto benzyl group of type B
(2JHH=11.4 Hz), evidently due to the higher basicity of
the amino group [5]. Finally, the longer bridge between
the ring and the amido nitrogen does not affect the
intramolecular coordination significantly, as can be

132
J. Okuda et al. / Journal of Organometallic Chemistry 591 (1999) 127–137
Scheme 4.
crystallinity, but NMR spectroscopic data suggested the
expected structure. While 1H- and 13C-NMR spectra
indicate Cs-symmetry for both complexes, the change in
olefin polymerization in catalysts containing a thioether
function is thought to be due to the decrease in the
barrier to insertion of ethylene into the growing poly-
mer chain. The thioether ligand and the incoming
ethylene substrate [18] are more or less equal donors to
the electrophilic alkyl cation, and thus the stability of
the p-complex is decreased.
1
2
the magnitude of the JPC and JPC values for the ipso-
and ortho-carbon atoms in the 13C-NMR, as well as the
significant high-field shift of the 31P-NMR resonance
suggests an interaction of the phosphorus atom with
the metal center (Dl=34.8 for 6; 28.5 for 7). A similar
situation is reported for the half-sandwich complexes
Zr(h5:h1-C5H4CH2CH2PPh2)Cl3(THF) [16a] and Ti(h5-
C5H5)Cl2(OC6H3-tBu-6-PPh2) [16b] in which a metal–
phosphorus interaction is present, according to X-ray
crystallography and solution studies. In the absence of
crystallographic data, we hypothesize that intramolecu-
lar coordination of the PPh2 unit at the metal center is
preferred because of the rigid ortho-phenylene bridge
and the electron-withdrawing anilido group. The zirco-
nium complex 7 retains one molecule of THF, as
indicated by NMR spectroscopy. So far all attempts to
prepare the dialkyl complexes have failed (see Scheme
4).
4. Experimental
4.1. General considerations
All experiments were performed under argon using
standard Schlenk or glovebox techniques. Diethylether,
THF, pentane, and hexane were purified by distillation
from sodium–benzophenone ketyl. Toluene was dis-
tilled over sodium sand. H2NCH2CH2SH [19],
(C5Me4H)SiMe2Cl [7], (C5Me4H)CH2SiMe2Cl [4e],
Ti(h5-C5H4SiMe2Cl)Cl3
[20],
TiCl3(THF)3
[21],
ZrCl4(THF)2 [21], and Mg(CH2Ph)2(THF)2 [22] were
prepared according to literature procedures. All other
reagents were commercially available and used as re-
ceived. NMR spectra were recorded on a Bruker DRX
400 spectrometer (1H, 400 MHz; 13C, 101 MHz; 31P,
162 MHz; 19F, 376 MHz; 29Si, 79.5 MHz) at 298 K,
3. Conclusions
1
We have extended the class of tridentate linked
amido–cyclopentadienyl ligands to include soft donor
groups SMe and PPh2, which are well suited to form
semilabile ligands. We have noted significant differences
in the structures, solution dynamics, and reactivities of
the resulting titanium and zirconium complexes com-
pared with those containing the OMe- and NMe2-func-
tionalized systems [4,5]. Although the changes are
subtle, the nucleophilicity (donor ability) increases in
the order SMeBOMeBNMe2 and allows more ratio-
nal modifications to the electrophilicity at the metal
center. The role of sulfur donor groups in linked
bis(phenoxide) ligands has recently been studied both
experimentally [10] and theoretically [17] in view of the
commercial interest in olefin polymerization catalysts
based on Group 4 metal complexes with non-cyclopen-
tadienyl ligands [3]. The increase in the activity for
unless otherwise stated. Chemical shifts for H and 13C
spectra were referenced internally using the residual
solvent resonances and reported relative to tetramethyl-
silane. 19F spectra were referenced externally to CFCl3,
31P spectra to 85% H3PO4. Mass spectra were recorded
on a Finnigan 8230 spectrometer. Elemental analyses
were performed by the microanalytical laboratory of
this department.
4.2. (2-Aminoethyl)methylsulfide [23]
At 0°C a suspension of 2-aminoethanethiol (5.40 g,
70.0 mmol) in 40 ml of dry methanol was slowly treated
with 13.3 ml (70.0 mmol) of a 30% methanolic solution
of NaOMe and 10 ml of additional methanol. The
reaction mixture was allowed to warm up to r.t. and
concentrated to a volume of 30 ml. After addition of

J. Okuda et al. / Journal of Organometallic Chemistry 591 (1999) 127–137
133
10.1 g (71.0 mmol) of iodomethane, dissolved in 5 ml of
4.5. (C5Me4H)CH2SiMe2NCH2CH2SMe
methanol, the mixture was stirred for a further 2 h
followed by removal of the solvent in vacuo. After
addition of 10 ml of water and 1.5 g of sodium chlo-
ride, the aqueous phase was extracted with 3×10 ml of
CH2Cl2 and the combined organic layers were dried
over MgSO4. Fractional distillation at 40°C and 12
(C5Me4H)CH2SiMe2Cl (4.18 g, 18.3 mmol) was
added to a suspension of Li(NHCH2CH2SMe) (1.78 g,
18.2 mmol) in 70 ml of hexane at −78°C. The reaction
mixture was allowed to warm to r.t. and stirred for 14
h. Filtration of the resulting suspension and removal of
all volatiles in vacuo gave crude the product which was
distilled at 100–105°C and 8×10−3 mbar to give a
mixture of isomers as a yellow oil: yield 4.15 g (84%).
1H-NMR (C6D6): l 0.11, 0.15, 0.18 (s, 6H, SiCH3), 0.82
(s, 1H, NH), 1.13, 1.14, 1.17, 1.18 (total 2H, CH2Si),
1.86, 1.87, 1.90, 1.91, 1.93, 1.96 (s, 15H, C5(CH3)4,
SCH3), 2.39 (m, 2H, CH2S), 2.59, 2.60 (1H, C5Me4H),
2.88 (m, 2H, NCH2); 13C{1H}-NMR (C6D6): l −1.1,
−0.9, −0.8 (SiCH3), 11.4, 11.8, 12.0, 12.6, 14.8, 14.9,
17.0, 17.8 (C5(CH3)4, SMe, CH2Si), 39.2, 40.9, 51.3,
51.7 (CH2S, NCH2, ring C at CH2), 132.1, 134.7, 136.0,
136.6, 138.1, 139.7 (C5(CH3)4). Anal. Calc. for
C15H29NSSi: C, 63.54; H, 10.31; N, 4.94. Found C,
62.49; H, 10.78; N, 5.37%.
1
mbar afforded 1.89 g (30%) of a colorless oil. H-NMR
(CDCl3): l 1.37 (s, 2H, NH2), 1.95 (s, 3H, CH3), 2.45
2
2
(dt, JHH=6.3 Hz, 2H, CH2), 2.74 (dt, JHH=6.3 Hz,
2H, CH2).
4.3. Ti(p5:p1-C5H4SiMe2NCH2CH2SMe)Cl2 (1)
To a solution of Ti(h5-C5H4SiMe2Cl)Cl3 (0.92 g, 2.94
mmol) in 40 ml of THF, was added dropwise a solution
of Li(NHCH2CH2SMe) (0.29 g, 2.94 mmol) and tri-
ethylamine (0.30 g, 2.94 mmol) in 20 ml of THF at
−60°C. The mixture was allowed to warm to r.t. and
stirred for 3 h. All volatiles were removed in vacuo and
the residue was extracted with 40 ml of a 1:2 hexane–
toluene mixture. Filtration and concentration of the
extracts, followed by crystallization at −20°C afforded
4.6. Ti(p5:p1-C5Me4SiMe2NCH2CH2SMe)Cl2 (2a)
1
yellow crystals: yield 0.43 g (44%). H-NMR (C6D6): l
3
0.24 (s, 6H, SiCH3), 1.86 (s, 3H, SCH3), 2.47 (t, JHH
=
Crude Li2(C5Me4SiMe2NCH2CH2SMe) (1.86 g, 6.62
3
7.1 Hz, 2H, CH2S), 4.58 (t, JHH=7.1 Hz, 2H, NCH2),
6.17 (‘t’, 2H, C5H4), 6.57 (‘t’, 2H, C5H4); 13C{1H}-
NMR (C6D6): l 2.4 (SiCH3), 15.0 (SCH3), 34.8 (SCH2),
55.8 (NCH2), 109.2 (ring C at Si), 124.0, 126.0 (C5H4).
EI MS: m/z (%): 329 (16, M+), 268 (100, M+
−C2H5S), 240 (53, M+−C3H7NS), 205 (27, M+
−C3H7NS, −Cl). Anal. Calc. for C10H17Cl2NSSiTi: C,
36.38; H, 5.19; N, 4.24. Found: C, 36.57; H, 5.18; N,
4.195.
mmol),
obtained
by
deprotonation
of
(C5Me4H)SiMe2NHCH2CH2SMe with two equivalents
of n-butyllithium in hexane, was dissolved in 40 ml of
THF and added dropwise to
a suspension of
TiCl3(THF)3 (2.45 g, 6.62 mmol) in 40 ml of toluene at
−60°C. After warming to r.t., the green reaction mix-
ture was stirred for 2 h and treated with solid PbCl2
(1.84 g, 6.62 mmol). After stirring for 12 h, the solvent
was removed under vacuum and the residue was ex-
tracted with 80 ml of a 2:1 toluene–hexane mixture.
Filtration of the extracts, followed by concentrating the
filtrate and cooling to −20°C afforded in several crops
4.4. (C5Me4H)SiMe2NHCH2CH2SMe
(C5Me4H)SiMe2Cl (3.74 g, 17.4 mmol) was added to
a suspension of Li(NHCH2CH2SMe) (1.69 g, 17.4
mmol) in 60 ml of hexane at −78°C. The reaction
mixture was allowed to warm to r.t. and stirred for 14
h. Filtration of the resulting suspension and removal of
all volatiles in vacuo gave crude (C5Me4H)-
SiMe2NHCH2CH2SMe, which was distilled at 100°C
and 8×10−3 mbar to give a yellow oil: yield 3.33 g
1
of yellow crystals: yield 1.32 g (52%). H-NMR (C6D6):
l 0.45 (s, 6H, SiCH3), 1.94 (s, 3H, SCH3), 2.08 (s, 6H,
C5(CH3)4), 2.09 (s, 6H, C5(CH3)4), 2.60 (‘t’, 2H, CH2S),
4.50 (‘t’, 2H, NCH2); 13C{1H} (C6D6): l 6.0 (SiCH3),
12.8 (C5(CH3)4), 15.1 (SCH3), 16.0 (C5(CH3)4), 35.4
(CH2S), 53.8 (NCH2), 103.2 (ring C at Si), 136.0, 141.0
(C5(CH3)4); EI MS: m/z (%): 385 (11, M+), 370 (8,
M+−Me), 335 (14, M+−Me, −Cl), 324 (100, M+−
C2H5S), 296 (34, M+−C3H7NS). Anal. Calc. for
C14H25Cl2NSSiTi: C, 43.53; H, 6.52; N, 3.63. Found: C,
44.06; H, 7.59; N, 3.87%.
1
(71%). H-NMR (C6D6) of the 5-isomer: l 0.10 (s, 6H,
SiCH3), 0.78 (s, 1H, NH), 1.82 (s, 3H, SCH3), 1.96 (s,
6H, C5(CH3)4), 2.09 (s, 6H, C5(CH3)4), 2.39 (‘t’, 2H,
CH2S), 2.85 (‘t’, 2H, NCH2), 2.89 (s, 1H, C5Me4H);
13C{1H}-NMR (C6D6): l 2.2 (SiCH3), 11.4, 14.6
(C5(CH3)4), 15.0 (SCH3), 39.1 (CH2S), 40.9 (NCH2),
56.7 (ring C at Si), 132.7, 135.6 (C5(CH3)4); EI MS: m/z
(%): 269 (55, M+), 254 (23, M+−CH3), 222 (17,
M+−SCH3), 208 222 (17, M+−SC2H5). Anal. Calc.
for C14H27NSSi: C, 62.39; H, 10.10; N, 5.20. Found: C,
61.89; H, 10.29; N, 5.55%.
4.7. Ti(p5:p1-C5Me4CH2SiMe2NCH2CH2SMe)Cl2 (2b)
Crude Li2(C5Me4CH2SiMe2NꢀCH2CH2SMe) (2.80 g,
9.50 mmol), obtained by double deprotonation of
(C5Me4H)CH2SiMe2NHCH2CH2SMe with n-butyl-
lithium in hexane, was dissolved in 120 ml of THF and

134
J. Okuda et al. / Journal of Organometallic Chemistry 591 (1999) 127–137
3
added dropwise to a suspension of TiCl3(THF)3 (3.51 g,
9.50 mmol) in 30 ml of THF at −60°C. After warming
up to r.t., the reaction mixture was stirred for 2 h and
treated with PbCl2 (2.64 g, 9.50 mmol). After stirring
for 12 h, the solvent was removed under vacuum and
the residue was extracted with 150 ml of 2:1 toluene–
hexane mixture and filtered. Concentrating the filtrate
and crystallization at −20°C afforded yellow crystals:
yield 1.48 g (39%). 1H-NMR (C6D6): l 0.12 (s, 6H,
SiCH3), 1.94 (s, 6H, C5(CH3)4), 1.96 (s, 2H, CH2Si),
2.14 (s, 6H, C5(CH3)4), 2.16 (s, 3H, SCH3), 2.74 (‘t’, 2H,
CH2S), 4.49 (‘t’, 2H, NCH2); 13C{1H}-NMR (C6D6): l
2.2 (SiCH3), 13.3, 13.4 (C5(CH3)4), 15.0 (CH2Si), 15.3
(SCH3), 33.4 (CH2S), 51.0 (NCH2), 128.6, 128.8
(C5(CH3)4), 134.4 (ring C at CH2); EI MS: m/z (%) 398
(12, M+), 337 (100, M+−C2H5S), 309 (6, M+−
C3H7SN), 302 (9, M+−Cl, −C2H5S). Anal. Calc. for
C15H27NCl2SSiTi: C, 45.01; H, 6.80; N, 3.50. Found: C,
44.85; H, 6.71; N, 3.71%.
7.01 (m, 6H, C6H5), 7.30 (d, JHH=8.2 Hz, 4H, ortho-
C6H5); 13C{1H}-NMR (C6D6): l 3.4 (SiCH3), 11.4, 14.8
(C5(CH3)4), 15.3 (SCH3), 36.8 (CH2S), 52.2 (NCH2),
80.5 (CH2Ph), 97.6 (ring C at Si), 122.2 (para-C6H5),
126.9 (ortho-C6H5), 128.6 (meta-C6H5), 129.6, 135.1
(C5(CH3)4), 149.0 (ipso-C6H5); EI MS: m/z (%): 496
(25, M+), 465 (4, M+−C2H7), 301 (3, M+−C15H15).
Anal. Calc. for C28H39NSSiTi: C, 67.58; H, 7.90; N,
2.81. Found: C, 65.47; H, 7.86; N, 3.67%.
4.10. Ti(p5:p1-C5Me4CH2SiMe2NCH2CH2SMe)-
(CH2Ph)2 (4b)
Hexane (50 ml) was added to a solid mixture of
Ti(h5:h1-C5Me4CH2SiMe2NCH2CH2SMe)Cl2 (0.39 g,
0.98 mmol) and Mg(CH2Ph)2(THF)2 (0.40 g, 1.14
mmol) at −78°C. The mixture was allowed to warm to
r.t. and stirred for 14 h. All volatiles were removed in
vacuo and the residue was extracted with 30 ml of
hexane. After filtration, the red solution was concen-
trated and cooled to −20°C to give red crystals: yield
4.8. Zr(p5:p1-C5Me4SiMe2NCH2CH2SMe)Cl2 (3)
1
0.31 g (61%). H-NMR (C6D6): l 0.20 (s, 6H, SiCH3),
1.73 (s, 6H, C5(CH3)4), 1.78 (s, 2H, CH2Si), 1.91 (s, 3H,
A mixture of ZrCl4(THF)2 (1.95 g, 5.17 mmol) and
Li2(C5Me4SiMe2NCH2CH2SMe) (1.45 g, 5.17 mmol)
was treated dropwise with 60 ml of toluene at −60°C
and stirred for 2 days at r.t. All volatiles were removed
in vacuo and the residue extracted with hexane. Filtra-
tion of the extracts, followed by concentrating the
filtrate and cooling to −50°C afforded colorless crys-
2
SCH3), 1.98 (s, 6H, C5(CH3)4), 2.21 (d, JHH=10.6 Hz,
2H, CH2Ph), 2.30 (d, 2JHH=10.6 Hz, 2H, CH2Ph), 2.49
(m, 2H, CH2S), 4.26 (m, 2H, NCH2), 7.03 (m, 6H,
C6H5), 7.29 (m, 4H, C6H5); 13C{1H}-NMR (C6D6): l
3.0 (SiCH3), 11.9, 12.2 (C5(CH3)4), 15.1, 15.3 (CH2Si,
1
1
SMe), 35.6 (t, JCH=140 Hz, CH2S), 50.0 (t, JCH
=
1
tals: yield 0.93 g (42%). H-NMR (C6D6): l 0.46 (s, 6H,
135.5 Hz, NCH2), 78.9 (t, 1JCH=121 Hz, CH2Ph),
121.6 (C5(CH3)4), 122.2 (para-C6H5), 123.5 (C5(CH3)4),
125.4 (ring C at CH2), 127.0 (ortho-C6H5), 128.4 (meta-
SiCH3), 1.97 (s, 3H, SCH3), 2.20 (s, 6H, C5(CH3)4), 2.25
(s, 6H, C5(CH3)4), 2.52 (‘t’, 2H, CH2SMe), 3.21 (‘t’, 2H,
NCH2); 13C{1H}-NMR (C6D6): l 2.4 (SiCH3), 12.0,
14.7 (C5(CH3)4), 16.1 (SCH3), 38.1 (CH2S), 49.6
(NCH2), 101.2 (ring C at Si), 130.8, 131.7 (C5(CH3)4);
EI MS: m/z (%) 428 (21, M+), 413 (62, M+−Me), 381
(11, M+−SMe), 368 (39, M+−C2H6S), 339 (21, M+
−C3H7NS), 304 (10, M+−C3H7NS, −Cl). Anal.
Calc. for C14H25Cl2NSSiZr: C, 39.14; H, 5.86; N, 3.26.
Found: C, 39.01; H, 5.28; N, 3.43%.
C6H5),
150.4
(ipso-C6H5);
Anal.
Calc.
for
C29H41NSSiTi: C, 68.07; H, 8.08; N, 2.74. Found: C,
67.33; H, 7.36; N, 2.48%.
4.11. [Ti(p5:p1-C5Me4SiMe2NCH2CH2SMe)-
(CH2Ph)][B(C6F5)3] (5a)
C6D5Br (0.5 ml) was added to a solid mixture of the
dibenzyl complex 4a (18 mg, 36 mmol) and B(C6F5)3 (18
mg, 35 mmol) in an NMR tube at −10°C. The color of
the solution turned brown upon warming up to r.t.
1H-NMR (C6D5Br, −5°C): l 0.30 (s, 3H, SiCH3), 0.57
(s, 3H, SiCH3), 1.46 (s, 3H, C5(CH3)4), 1.67 (s, 3H,
C5(CH3)4), 2.15 (s, 3H, SMe), 2.16 (s, 3H, C5(CH3)4),
2.17 (s, 3H, C5(CH3)4), 2.59 (d, 2JHH=6.3 Hz, 1H,
TiCH2Ph), 2.71 (m, 1H, CH2S), 2.95 (m, 1H, CH2S),
4.9. Ti(p5:p1-C5Me4SiMe2NCH2CH2SMe)(CH2Ph)2
(4a)
A mixture of 0.54 g (1.40 mmol) of Ti(h5:h1-
C5H4SiMe2NCH2CH2SMe)Cl2 and 0.50 g (1.43 mmol)
of Mg(CH2Ph)2(THF)2 was treated dropwise with 30 ml
of hexane at −60°C and stirred for 20 h at r.t. Evapo-
ration of the solvent and extraction of the residue with
2×15 ml of hexane, followed by filtration of the
extracts, concentrating the filtrate and cooling to
2
3.15 (d, JHH=6.3 Hz, 1H, TiCH2Ph), 3.24 (m, 1H,
NCH2), 3.61 (br s, 2H, BCH2Ph), 3.95 (m, 1H, NCH2),
6.28 (br s, 2H, ortho-C6H5), 7.29 (m, 10H, C6H5);
13C{1H}-NMR (C6D5Br, −5°C): l 0.5, 2.7 (SiMe),
11.3, 13.3 (C5(CH3)4), 16.0, 16.1, 17.8 (C5(CH3)4, SMe),
1
−50°C afforded red crystals: yield 0.43 g (62%). H-
NMR (C6D6): l 0.40 (s, 6H, SiCH3), 1.83 (s, 6H,
C5(CH3)4), 1.92 (s, 6H, C5(CH3)4), 1.94 (s, 3H, SCH3),
2
2.20 (d, JHH=10.2 Hz, 2H, CH2Ph), 2.36 (overlap. m,
32.9 (BCH2), 51.3 (CH2S), 52.3 (NCH2), 72.3 (t, 1JCH
=
3
4H, CH2Ph, CH2S), 3.98 (t, JHH=7.8 Hz, 2H, NCH2),
150 Hz, TiCH2), 110.1 (ring C am Si), 121.3, 122.4,

J. Okuda et al. / Journal of Organometallic Chemistry 591 (1999) 127–137
135
1
123.1, 123.3, 127.6, 129.4 (C6H5), 132.8, 133.0, 133.3
(C5(CH3)4), 135.9 (C6F5), 136.6, 136.8, 137.6 (C6H5,
C5(CH3)4), 138.3 (C6F5), 139.2 (C6H5), 147.7 (C6F5),
149.2 (ipso-BCH2C6H5), 150.1 (C6F5); 19F-NMR
(C6H4-3), 136.4 (d, JPC=9 Hz, ipso-C6H5), 150.8 (d,
2JPC=20 Hz, C6H4-1); 31P{1H}-NMR (C6D6):
l
−17.0. EI MS: m/z (%) 277 (100, M+), 261 (8, M+
−NH2), 185 (9, M+−C6H6N).
3
(C6D6Br, −5°C): l −130.1 (d, JFF= 22.9 Hz, ortho-
3
C6F5), −163.7 (t, JFF=22.9 Hz, para-C6F5), −166.6
4.14. {(C5Me4H)SiMe2NHC6H4(PPh2)-2}
3
(t, JFF=20.7 Hz, meta-C6F5).
(C5Me4H)SiMe2Cl (1.17 g, 5.46 mmol) was added to
a suspension of Li{NHC6H4(PPh2)-2} (1.55 g, 5.46
mmol) in 40 ml of hexane at −60°C. The reaction
mixture was allowed to warm to r.t. and stirred for 14
h. Filtration of the resulting suspension and removal of
all volatiles in vacuo gave crude (C5Me4H)SiMe2-
NHC6H4(PPh2)-2 as a slightly brown, waxy solid: yield
4.12. [Ti(p5:p1-C5Me4CH2SiMe2NCH2CH2SMe)-
(CH2Ph)][B(C6F5)3] (5b)
C6D5Br (0.5 ml) was added to an equimolar mixture
of dibenzyl 4b (12 mg, 25 mmol) and B(C6F5)3 (13 mg,
25 mmol) in an NMR tube at −10°C. The color turned
brown upon warming up to r.t. 1H-NMR (C6D5Br,
−5°C): l 0.05 (s, 3H, SiCH3), 0.28 (s, 3H, SiCH3), 1.47
(s, 3H, C5(CH3)4), 1.74 (s, 3H, C5(CH3)4), 1.97 (d,
2JHH=14.5 Hz, 1H, CH2Si), 2.10, 2.11 (s, 3H,
C5(CH3)4; s, 3H, SCH3), 2.14 (overlap d, 1H, CH2Si),
2.24 (s, 3H, C5(CH3)4), 2.68 (m, 1H, CH2S), 2.76 (d,
2JHH=7.4 Hz, 1H, TiCH2), 2.87 (m, 2H, CH2S,
1
2.14 g (86%). H-NMR (C6D6): l 0.24 (s, 6H, SiCH3),
1.38 (s, 1H, NH), 1.90 (s, 6H, C5(CH3)4), 1.97 (s, 6H,
C5(CH3)4), 3.06 (s, 1H, C5Me4H), 6.73 (‘t’, 1H, C6H4),
7.02 (m, 1H, C6H5, C6H4), 7.12 (m, 6H, C6H5, C6H4),
7.21 (m, 2H, C6H5, C6H4), 7.47 (m, 4H, C6H5, C6H4);
13C{1H}-NMR (C6D6): l −1.9 (SiCH3), 11.5, 14.3
(C5(CH3)4), 54.9 (ring C at Si), 115.9 (C6H4-6), 118.7
1
(C6H4-4), 122.3 (d, JPC=5 Hz, C6H4-2), 128.6 (meta-
2
NCH2), 3.32 (d, JHH=7.4 Hz, 1H, TiCH2), 3.55 (br s,
C6H5), 128.8 (para-C6H5), 129.3 (C5(CH3)4), 130.8
(C6H4-5), 132.4 (C5(CH3)4), 134.1 (d, 2JPC=19 Hz,
ortho-C6H5), 135.5 (C6H4-3), 136.5 (d, 1JPC=8 Hz,
3
2H, BCH2), 3.87 (m, 1H, NCH2), 6.38 (d, JHH=4.7
Hz, 2H, ortho-C6H5), 7.07 (m, 2H, C6H5), 7.32 (m, 6H,
C6H5); 13C{1H}-NMR (C6D5Br, −5°C): l 0.5, 1.8
(SiCH3), 11.2 (C5(CH3)4), 13.5, 13.8, 14.3, 16.1, 17.8
(C5(CH3)4, SCH3, CH2Si), 32.5 (BCH2), 48.3 (CH2S),
52.8 (NCH2), 74.2 (t, 1JCH=144 Hz, TiCH2), 121.3,
122.4, 123.1, 123.3, 124.4, 124.5, 126.0, 127.6, 128.1,
129.4, 131.4 (C6H5, C5(CH3)4), 132.8, 133.0, 133.3
(C5(CH3)4), 135.4 (C6H5), 135.8 (C6F5), 137.2 (C6H5),
138.4, 139.4, 147.8 (C6F5), 149.3 (ipso-BCH2C6H5),
150.2 (C6F5); 19F-NMR (C6D5Br, −5°C): l −130.3
2
ipso-C6H5), 151.6 (d, JPC=20 Hz, C6H4-1);.31P{1H}-
NMR (C6D6): l −18.4. EI MS: m/z (%) 455 (100,
M+).
4.15. Ti{p5:p1-C5Me4SiMe2NC6H4(PPh2)-2}Cl2 (6)
A solution of crude Li2{C5Me4SiMe2NC6H4(PPh2)-
2}, obtained by double deprotonation of (C5Me4H)-
SiMe2NHC6H4(PPh2)-2 (2.14 g, 4.70 mmol) with n-
BuLi in 40 ml of toluene, was added dropwise to a
suspension of TiCl3(THF)3 (1.74 g, 4.70 mmol) in 20 ml
of THF at −60°C. After warming up to r.t. the
reaction mixture was stirred for 4 h and treated with
PbCl2 (1.31 g, 4.70 mmol). After stirring for 14 h, the
solvent was removed under vacuum and the residue was
extracted with 60 ml of 2:1 toluene–hexane mixture
and filtered. Evaporation of the solvent gave brown
3
3
(d, JFF=20.8 Hz, ortho-C6F5), −163.7 (t, JFF=20.8
Hz, para-C6F5), −166.5 (t, 3JFF=20.8 Hz, meta-
C6F5).
4.13. Ortho-diphenylphosphinoaniline [15]
Diphenylphosphine (2.22 g, 11.9 mmol) was added to
a solution of 2-iodoaniline (2.61 g, 11.9 mmol) and
triethylamine (1.66 ml, 11.9 mmol) in 30 ml of acetoni-
trile. The reaction mixture was treated with Pd(PPh3)4
(0.14 g, 0.12 mmol) in 10 ml of acetonitrile and 10 ml
of water and stirred under reflux for 40 h. The solvent
was removed in vacuo and the residue was extracted
with 30 ml of a 1:1 H2O–CH2Cl2 mixture. After re-
moval of the solvent the organic layer afforded a brown
1
microcrystals: yield 1.48 g (55%). H-NMR (C6D6): l
0.69 (s, 6H, SiCH3), 2.10 (s, 6H, C5(CH3)4), 2.19 (s, 6H,
C5(CH3)4), 6.79 (m, 1H, C6H4), 6.87 (m, 1H, C6H4),
7.12 (m, 8H, C6H5, C6H4), 7.76 (m, 4H, C6H5, C6H4);
13C{1H}-NMR (C6D6): l 2.7 (SiCH3), 13.0, 15.6
3
(C5(CH3)4), 108.8 (ring C at Si), 116.5 (d, JPC=6 Hz,
C6H4-6), 123.1 (d, 3JPC=3 Hz, C6H4-4), 124.4 (d,
1
2
solid: yield 2.66 g (81%). H-NMR (C6D6): l 3.85 (br s,
1JPC=26 Hz, C6H4-2), 127.9 (C6H4-5), 128.6 (d, JPC
=
2H, NH2), 6.43 (m, 1H, C6H5, C6H4), 6.70 (‘t’, 1H,
C6H4), 7.13 (m, 8H, C6H5, C6H4), 7.50 (m, 4H, C6H5,
C6H4); 13C{1H}-NMR (C6D6): l 115.3 (C6H4-6), 118.7
(C6H4-4), 119.2 (d, 1JPC=9 Hz, C6H4-2), 128.0 (d,
3JPC=3 Hz, meta-C6H5), 128.8 (para-C6H5), 130.7
(C6H4-5), 134.1 (d, 2JPC=19 Hz, ortho-C6H5), 134.8
22 Hz, C6H4-3), 128.8 (meta-C6H5), 129.7 (para-C6H5),
2
132.2 (C5(CH3)4), 133.8 (d, JPC=19 Hz, ortho-C6H5),
1
134.1 (d, JPC=12 Hz, ipso-C6H5), 135.2 (C5(CH3)4),
2
162.6 (d, JPC=32 Hz, C6H4-1); 31P{1H}-NMR (C6D6):
l 16.4; EI MS: m/z (%)=571 (1, M+), 275 (73,
NC6H4PPh+2 ), 185 (50, PPh+2 ).

136
J. Okuda et al. / Journal of Organometallic Chemistry 591 (1999) 127–137
4.16. Zr{p5:p1-C5Me4SiMe2NC6H4(PPh2)-2}Cl2(THF)
(7)
Data Centre, CCDC no. 126008 for 1, and 126009 for
3. Copies of this information may be obtained free of
charge from The Director, CCDC, 12 Union Road,
Cambridge CB2 1EZ, UK (fax: +44-1223-336-033 or
Crude Li2{C5Me4SiMe2NC6H4(PPh2)-2} (4.11 g, 8.8
mmol), obtained by deprotonation of (C5Me4H)-
SiMe2NHC6H4(PPh2)-2 with 2 equivalents of n-butyl-
lithium in hexane, was dissolved in 45 ml of toluene and
added dropwise to a solution of ZrCl4(THF)2 (3.32 g,
8.8 mmol) in 45 ml of toluene cooled to −78°C. The
mixture was allowed to warm up to r.t. and stirred for
additional 15 h. The solvent was evaporated and the
residue was extracted with 100 ml of a 2:1 toluene–hex-
ane mixture. Filtration of the extracts, followed by
concentrating the filtrate afforded a colorless solid: yield
e-mail:
deposit@ccdc.cam.ac.uk
or
http://www.
ccdc.cam.ac.uk).
Acknowledgements
This work was supported by the Fonds der Chemi-
schen Industrie, BASF AG (Kunststofflaboratorium),
and the Bundesministerium fu¨r Bildung, Wissenschaft,
Forschung und Technologie. V.P. thanks the Alexander
1
3.71 g (68%). H-NMR (C6D6): l 0.70 (s, 6H, SiCH3),
von Humboldt Foundation for
fellowship.
a
postdoctoral
1.43 (m, 4H, b-CH2 of THF), 2.03 (s, 6H, C5(CH3)4),
2.10 (s, 6H, CCH3), 3.62 (m, 4H, a-CH2 of THF) 6.64
(m, 1H, C6H5, C6H4), 6.87 (m, 1H, C6H5, C6H4), 7.01
(m, 6H, C6H5, C6H4), 7.42 (m, 2H, C6H5, C6H4), 7.75
(m, 4H, C6H5, C6H4); 13C{1H}-NMR (C6D6): l 4.0
(SiCH3), 11.9, 14.3 (C5(CH3)4), 25.7 (b-CH2 of THF),
68.1 (a-CH2 of THF), 102.2 (ring C at Si), 117.7 (d,
References
[1] (a) A.L. McKnight, R.M. Waymouth, Chem. Rev. 98 (1998)
2587. (b) J. Okuda, T. Eberle, in: A. Togni, R.L. Halterman
(Eds.), Metallocenes, Wiley–VCH, Weinheim, 1998, p. 415.
[2] (a) H.H. Brintzinger, D. Fischer, R. Mu¨lhaupt, B. Rieger, R.M.
Waymouth, Angew. Chem. 107 (1995) 1255; Angew. Chem. Int.
Ed. Engl. 34 (1995) 1143. (b) P.C. Mo¨hring, N.J. Coville, J.
Organomet. Chem. 479 (1994) 1.
3
3JPC=8 Hz, C6H4-6), 120.5 (d, JPC=5 Hz, C6H4-4),
1
3
122.1 (d, JPC=36 Hz, C6H4-2), 128.6 (d, JPC=9 Hz,
2
meta-C6H5), 130.0 (para-C6H5), 131.9 (d, JPC=29 Hz,
ortho-C6H5), 132.1 (C5(CH3)4), 132.8 (C6H4-5), 133.8
1
(C5(CH3)4), 134.0 (d, JPC=11 Hz, ipso-C6H5), 135.3
(C6H4-3), 161.9 (d, 2JPC=32 Hz, C6H4-1); 31P{1H}-
NMR (C6D6): l 10.1; 29Si{1H}-NMR: l −16.1 (d,
4JPSi=5.9 Hz); EI MS: m/z (%) 615 (22, M+), 430 (11,
M+−PPh2), 318 (4, M+−Cl, −C6H4PPh2), 275 (39,
NC6H4PPh+2 ).
[3] G.J.P. Britovsek, V.C. Gibson, D.F. Wass, Angew. Chem. 111
(1999) 448; Angew. Chem. Int. Ed. 38 (1999) 428.
[4] (a) K.E. du Plooy, U. Moll, S. Wocadlo, W. Massa, J. Okuda,
Organometallics 14 (1995) 3129. (b) J. Okuda, K.E. du Plooy,
W. Massa, H.C. Kang, U. Rose, Chem. Ber. 129 (1996) 275. (c)
F. Amor, K.E. du Plooy, T.P. Spaniol, J. Okuda, J. Organomet.
Chem. 558 (1998) 139. (d) F. Amor, T.P. Spaniol, J. Okuda,
Organometallics 16 (1997) 4765. (e) T. Eberle, Ph.D. Thesis,
University of Mainz, Germany, 1999. (f) K.C. Hultzsch, T.P.
Spaniol, J. Okuda, Organometallics 16 (1997) 4845. (g) K.C.
Hultzsch, T.P. Spaniol, J. Okuda, Organometallics 17 (1998)
485.
4.17. X-ray crystal structural analysis and
determination of the structures of 1 and 3
Data sets were obtained with an Enraf–Nonius
CAD4 diffractometer in the ꢀ-scan mode. The reflec-
tions were corrected for Lp effects using the program
[5] F. Amor, A. Butt, K.E. du Plooy, T.P. Spaniol, J. Okuda,
Organometallics 17 (1998) 5836.
system
MolEN [24] and for absorption using „-scans
[6] (a) J.M. Canich, G.G. Hlatky, H.W. Turner, PCT Appl. WO
92-00333 (1992). J.M. Canich, Eur. Patent Appl. EP 420 436-A1
(1991) (Exxon Chemical Co.). (b) J.C. Stevens, F.J. Timmers,
D.R. Wilson, G.F. Schmidt, P.N. Nickias, R.K. Rosen, G.W.
Knight, S. Lai, Eur. Patent Appl. EP 416 815-A2 (1991) (Dow
Chemical Co.). (c) D.D. Devore, F.J. Timmers, D.L. Hasha,
R.K. Rosen, T.J. Marks, P.A. Deck, C.L. Stern, Organometal-
lics 14 (1995) 3132. (d) Y.X. Chen, C.C. Stern, S. Yang, T.J.
Marks, J. Am. Chem. Soc. 118 (1996) 12 451. (e) Y.X. Chen, T.J.
Marks, Organometallics 16 (1997) 3649.
[25]. All structures were solved by Patterson and Fourier
methods using the program SHELXS-86 [26a]. The refin-
ements were carried out using the program SHELXL-93
based on F2 [26b]. Anisotropic thermal parameters were
refined for all non-hydrogen atoms. The hydrogen
atoms of the methyl groups in 3 were incorporated into
idealized positions of tetrahedral geometry by applying
rotating group refinements. All other hydrogen atoms
were located and refined with isotropic thermal parame-
ters. Results are given in Table 1.
[7] (a) P.J. Shapiro, E.E. Bunel, W.P. Schaefer, J.E. Bercaw,
Organometallics 9 (1990) 867. (b) P.J. Shapiro, W.D. Cotter,
W.P. Schaefer, J.A. Labinger, J.E. Bercaw, J. Am. Chem. Soc.
116 (1994) 4623.
[8] J.J. Eshuis, Y.Y. Tan, A. Meetsma, J.H. Teuben, J. Renkema,
G.G. Evens, Organometallics 11 (1992) 362.
[9] (a) M. Aizenberg, L. Turculet, W.M. Davis, F. Schattenmann,
R.R. Schrock, Organometallics 17 (1998) 4795. (b) D.D. Graf,
R.R. Schrock, W.M. Davis, R. Stumpf, Organometallics 18
(1999) 843.
5. Supplementary material
Crystallographic data for the structural analyses have
been deposited with the Cambridge Crystallographic

J. Okuda et al. / Journal of Organometallic Chemistry 591 (1999) 127–137
137
[10] (a) M. Kakugo, T. Miyatake, K. Mizunuma, Chem. Express 2
(1987) 445. (b) T. Miyatake, K. Mizunuma, Y. Seki, M. Kakugo,
Makromol. Chem., Rapid Commun. 10 (1989) 349. (c) T. Miy-
atake, K. Mizunuma, M. Kakugo, Makromol. Chem. Macro-
mol. Symp. 66 (1993) 203. (d) C.J. Schaverien, A.J. van der
Linden, A.G. Orpen, Am. Chem. Soc. Polym. Div. Polym.
Prepr. 35 (1994) 672. (e) C.J. Schaverien, A.J. van der Linden,
A.G. Orpen, J. Am. Chem. Soc. 117 (1995) 3008. (f) S. Fokken,
T.P. Spaniol, H.C. Kang, W. Massa, J. Okuda, Organometallics
15 (1996) 5069. (g) L. Porri, A. Ripa, P. Colombo, E. Miano, S.
Capelli, S.V. Meille, J. Organomet. Chem. 514 (1996) 213.
[11] (a) D.P. Krut’ko, M.V. Borzov, V.S. Petrosyan, L.G. Kuz’mina,
A.V. Churakov, Russ. Chem. Bull. 45 (1996) 1740. (b) D.P.
Krut’ko, M.V. Borzov, V.S. Petrosyan, L.G. Kuz’mina, A.V.
Churakov, D.A. Lemenovskii, O.A. Reutov, Inorg. Chim. Acta
280 (1998) 257.
Willoughby, R.R. Duff, Jr., W.M. Davis, S.L. Buchwald,
Organometallics 15 (1996) 472. (c) J.A. van Doorn, H. van der
Heijden, A.G. Orpen, Organometallics 13 (1994) 4271.
[17] (a) R.D.J. Froese, D.G. Musaev, T. Matsubara, K. Morokuma,
J. Am. Chem. Soc. 119 (1997) 7190. (b) R.D.J. Froese, D.G.
Musaev, K. Morokuma, Organometallics 18 (1999) 373.
[18] (a) Z. Wu, R.F. Jordan, J.L. Petersen, J. Am. Chem. Soc. 117
(1995) 5867. (b) C.P. Casey, S.L. Hallenbeck, J.M. Wright, C.R.
Landis, J. Am. Chem. Soc. 119 (1997) 9680. (c) M.V. Galakhov,
G. Heinz, P. Royo, Chem. Commun. (Cambridge) (1998) 17.
[19] R.E. Davis, S.P. Molnar, R. Nehring, J. Am. Chem. Soc. 91
(1969) 91.
[20] S. Ciruelos, T. Cuenca, P. Go´mez-Sal, A. Manzanero, P. Royo,
Organometallics 14 (1995) 177.
[21] L.E. Manzer, Inorg. Synth. 21 (1982) 135.
[22] R.R. Schrock, J. Organomet. Chem. 122 (1976) 209.
[23] D.R. Burfield, S.N. Gan, R.H. Smithers, J. Chem. Soc. Perkin
Trans. I (1977) 666.
[12] (a) J. Okuda, T. Eberle, T.P. Spaniol, Chem. Ber. 130 (1997)
209. (b) J. Okuda, T. Eberle, T.P. Spaniol, Eur. J. Inorg. Chem.
(1998) 237.
[13] A.D. Horton, J. de With, A.J. van der Linden, H. van de Weg,
Organometallics 15 (1996) 2672.
[24] C.K. Fair,
MolEN, An Interactive Structure Solution Procedure,
Enraf–Nonius, Delft, The Netherlands, 1990.
[25] A.C.T. North, D.C. Phillips, F. Scott Mathews, Acta Crystal-
logr. Sect. A 24 (1968) 351.
[14] P.-J. Sinnema, K. Liekelma, O.K.B. Staal, B. Hessen, J.H.
Teuben, J. Mol. Cat. 128 (1998) 143.
[26] (a) G.M. Sheldrick, SHELXS-86, A Program for Crystal Structure
Solution, University of Go¨ttingen, Germany, 1993. (b) G.M.
Sheldrick, SHELXL-93, A Program for Crystal Structure Refine-
ment, University of Go¨ttingen, Germany, 1993.
[15] O. Herd, A. Hessler, M. Hingst, M. Tepper, O. Stelzer, J.
Organomet. Chem. 522 (1996) 69.
[16] (a) D.P. Krut’ko, M.V. Borzov, N.E. Veksler, A.V. Churakov,
J.A.K. Howard, Polyhedron 17 (1998) 3889. (b) C.A.
.