Investigation of titanium-catalysed dehydrogenative coupling and hydrosilylation of phenylhydrogenosilanes in a one-pot process

Article abstract of DOI:10.1016/j.jorganchem.2009.03.018

Titanium-catalysed dehydrocondensation and hydrosilylation of primary, secondary and tertiary phenylsilanes have been investigated in a one-pot process with Cp₂Ti(OPh)₂ as catalyst by NMR studies. Only primary and secondary silanes were found to undergo simultaneous dehydrogenative coupling and hydrosilylation reactions to produce the functional polysilanes.

Full text of DOI:10.1016/j.jorganchem.2009.03.018

Journal of Organometallic Chemistry 694 (2009) 2427–2433
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Journal of Organometallic Chemistry
journal homepage: www.elsevier.com/locate/jorganchem
Investigation of titanium-catalysed dehydrogenative coupling and hydrosilylation
of phenylhydrogenosilanes in a one-pot process
c
a
a,
Julien Garcia a,b, Daniel J.M. Meyer b, , Denis Guillaneux , Joël J.E. Moreau , Michel Wong Chi Man
*
*
a Institut Charles Gerhardt Montpellier, UMR 5253, CNRS-UMII-ENSCM-UMI, Laboratoire Architectures Moléculaires et Matériaux Nanostructurés, Ecole Nationale Supérieure
de Chimie de Montpellier, 8, rue de l’école normale, 34296 Montpellier cédex 05, France
b Institut de chimie séparative de Marcoule, UMR 5257, BP 17171, 30207 Bagnols-sur-Cèze, France
c Laboratoire de conception des architectures moléculaires, VRH/DEN/DRCP/SCPS/LCAM-CEA Marcoule, Atalante, BP 17171, 30207 Bagnols-sur-Cèze, France
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 6 January 2009
Received in revised form 10 March 2009
Accepted 11 March 2009
Available online 20 March 2009
Titanium-catalysed dehydrocondensation and hydrosilylation of primary, secondary and tertiary phenyl-
silanes have been investigated in a one-pot process with Cp2Ti(OPh)2 as catalyst by NMR studies. Only
primary and secondary silanes were found to undergo simultaneous dehydrogenative coupling and
hydrosilylation reactions to produce the functional polysilanes.
Ó 2009 Elsevier B.V. All rights reserved.
Keywords:
Polysilane
Dehydrogenative coupling
Hydrosilylation
Titanium catalyst
Polymerisation
NMR studies
1. Introduction
Although the two reactions have already been observed with a sec-
ondary silane (PhMeSiH2) in the presence of an olefin [9c], no
The search for efficient new materials with tailored properties is
of significant interest for applications. Polysilanes figure among
these materials which have long been synthesised and exploited
mainly for their optical, electronic and chemical properties [1].
Among the various synthetic methods which exist [2], the dehy-
drocoupling polymerisation of silanes is one of the most interest-
ing and effective way for preparing these polymers [3]. These
reactions were initially performed following Harrod’s pioneering
work with titanium catalysts and in this field, new catalysts based
on group 4 metallocenes afterwards proved to be the most active
[4,5]. Cp2Ti(OPh)2 [6] figures among these catalysts and gave inter-
esting results in the polymerisation of PhSiH3 and also of Me-
SiH2(CH2)2SiH3 [7]. We are interested in synthesising functional
polysilanes and one possibility to achieve such materials involves
the hydrosilylation of the Si–H groups. The main drawback of this
route, until now, is the use of two different catalysts, one for the
dehydrogenative coupling (usually a metallocene catalyst) and
one for the hydrosilylation reaction (usually a platinum catalyst
or AIBN [8]). Ti, Zr and Hf are also known to promote the hydrosi-
lylation of olefins [9] but not as efficiently as platinum catalysts.
substituted polysilane was reported. Indeed, the formation of non
hydrosilylated oligosilanes was observed with the Cp2TiCl2/nBuLi
catalyst employed. More recently the dehydrocoupling of PhSiH3,
PhMeSiH2 and Ph2MeSiH was also studied in the presence of sev-
eral group 4 metallocenes [10].
Following these reported results, we envisaged a one-pot reac-
tion combining the dehydrocoupling of silanes and the hydrosily-
lation of an olefin with a titanocene derivative. We report here
our study by solution NMR (1H, 13C and 29Si) with a family of model
compounds based on phenylsilanes. These compounds consist of a
primary silane (PhSiH3), a secondary silane (Ph2SiH2), a tertiary si-
lane (Ph3SiH) and a tertiary di-silane (Ph2HSi–SiHPh2).
2. Results and discussion
Vinyltrimethoxysilane and Cp2(TiOPh)2 were selected as re-
agent and catalyst, respectively, for the hydrosilylation reactions
with the four silanes mentioned above. The reactions were studied
by solution NMR (1H, 13C and 29Si).
2.1. Reaction with the primary silane, PhSiH3
* Corresponding authors. Tel.: +33 467147219; fax: +33 467144353 (M.W.C.
Man).
PhSiH3 was mixed with the alkoxysilane (1/1 mole equivalent)
and catalyst (3 mole%) and the resulting mixture was heated to
E-mail addresses: daniel.meyer@cea.fr (D.J.M. Meyer), michel.wong-chi-man@-
enscm.fr (M. Wong Chi Man).
0022-328X/$ - see front matter Ó 2009 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2009.03.018

2428
J. Garcia et al. / Journal of Organometallic Chemistry 694 (2009) 2427–2433
Si(OMe)3
Si(OMe)3
Si(OMe)3
Ph
Si
Ph
1) Cp2Ti(OPh)2
50°C, 20 min
H
R
H
PhSiH3
1 mole eq.
+
Si
H
Si(OMe)3
Si(OMe)3
H
Ph Si
Ph Si
Ph Si
Si(OCH3)3
H
n
m
2) rt, 24h
1 mole eq.
H
Si(OMe)3
R
C
B
A
R
R
Si(OCH3)3
R
R
R
R
Ph Si Si Ph
Ph Si Si Si Ph
Ph
Ph Si
R
Si
Ph
Si Ph
R
Scheme 1. Reaction with the primary silane, PhSiH3.
R
R
R
R
n
functionalised oligomers
R = H, Si, CH2CH2Si(OMe)3
50 °C for 20 min until the catalyst was activated. The initial orange
solution turned dark blue. The reaction was monitored until the
alkoxysilane had been consumed (Scheme 1).
H3
H2
R
R
R
R
H1
H3
Si Si Si Si Si Si
Ph Ph
Ph Ph Ph
Ph
2.1.1. 1H NMR study
D
1H NMR enabled the evolution of the characteristic chemical
shifts of the reagents to be monitored. The chemical shifts of the
two reagents (PhSiH3 and vinyltrimethoxysilane) are depicted in
spectra (a) and (b), respectively, while spectrum (c) shows the evo-
lution of the reaction with time after complete consumption of the
alkoxysilane.
Scheme 2. Possible silicon sites obtained from reaction with PhSiH3.
2.1.2. 13C NMR study
The 13C spectrum of the reaction mixture (Fig. 2) confirms the
disappearance of the C-sp2 peak associated with the vinylic group
and also shows the formation of Si–CH2 (3 peaks at around 5 ppm),
as expected for the products of the hydrosilylation reaction. A
sharp peak is observed at around 50 ppm corresponding to the car-
bon atoms of the methoxy groups on silicon atoms. The phenylic
groups appear, as expected, as multiple peaks in the region of
125–135 ppm.
The comparison of these three spectra leads to two main obser-
vations. In spectrum (c), the chemical shifts at around 6 ppm
(vinylic protons) disappeared completely and consequently signals
between 0.5 to 1.2 ppm appeared. These are attributed to C-sp3
species bound to Si, which arise from quantitative hydrosilylation.
The Si–H3 signal at 4.25 ppm also completely disappeared and new
chemical shifts were observed at 4.95 (predominant) and 4.85 ppm
(Fig. 1, inset) which correspond to several new Si–H sites. Scheme
2 depicts a non-exhaustive list of different silicon sites likely to
form during the reaction. The formation of mono- to tri-functional-
ised monomers (A–C), functionalised dimers and trimers, as well as
a series of polyfunctionalised oligomers, are expected. Based on
previous work [11], the predominant peak at 4.95 ppm may be
attributed to Si–Si–H protons which are formed during the dehy-
drocoupling reaction (H2 and H3 in molecule D – Scheme 2). The
small triplet found at 4.85 ppm could correspond to a proton
bonded to a monohydrosilylated silicon site (for example in mole-
cule A and also H1 in molecule D for R = CH2CH2Si(OMe)3).
2.1.3. 29Si NMR study
The 29Si NMR spectrum (Fig. 3) exhibits several peaks, which are
assigned as follows [12]:
– The peak at À2.9 ppm is assigned to a silicon atom bonded to the
phenyl group and to three trimethoxysilylethenyl groups
(Scheme 2, compound C). This compound results from complete
hydrosilylation of the three H atoms of PhSiH3
– The peak at À16.4 ppm corresponds to the chemical shift of a
dihydrosilylated silicon atom bound to phenylene group and
either (a) one H atom (Scheme 2, compound B) [13]; or (b) a
Si atom arising the dehydrocoupling of the H atom [14].
Fig. 1. 1H NMR spectra of: (a) PhSiH3, (b) vinylSi(OMe)3, (c) reaction mixture of vinylSi(OMe)3 with PhSiH3 after 24 h.

J. Garcia et al. / Journal of Organometallic Chemistry 694 (2009) 2427–2433
2429
Fig. 2. 13C NMR spectrum of the reacting mixture of the reaction with PhSiH3.
also further polymerise into oligosilanes and polysilanes [17].
Two additional compounds may form from a monohydrosilylation
and a dihydrosilylation of the initial silane which would lead to
Ph2SiH–CH2–CH2–Si(OMe)3
respectively.
and
Ph2Si–[CH2–CH2–Si(OMe)3]2,
2.2.1. 1H NMR study
The 1H spectra of Ph2SiH2, vinyltrimethoxysilane and the corre-
sponding reaction mixture are shown in Fig. 4.
As in the case of the primary silane, the complete disappear-
ance of the protons (about 6 ppm) of the vinyl group of the alk-
oxysilane and the formation of Si–CH2 (0.5–1.2 ppm) in
spectrum (c) confirm the hydrosilylation of the double bonds.
Moreover the chemical shift at 5.13 ppm (Si–H2) is not observed.
Only a new peak (4.94 ppm) appeared, corresponding to a Ph2SiHC
environment. This chemical shift may correspond to either (a) the
proton of the monohydrosilylated secondary silane leading to the
formation of Ph2SiH–CH2–CH2–Si(OMe)3 or (b) the product
formed by monohydrosilylation of the dimer, Ph2HSi-SiPh2-CH2-
CH2-Si(OMe)3. The non-substituted dimer itself can be precluded
since no signal corresponding to its Si–H proton (4.90 ppm) is ob-
served. The peak at 0.5–1.2 ppm confirms the hydrosilylation
reaction.
Fig. 3. 29Si NMR spectrum of the reacting mixture of the reaction with PhSiH3.
– The peaks at around À40 ppm are attributed to a silicon atom
linked to three methoxy groups and one C-sp3, C–Si(OMe)3.
– The last peak at around À50 ppm is assigned to a monohydrosi-
lylated silicon atom bound to a phenyl group and two X groups
*
(PhSi (H)(Si/H)CH2CH2Si(OCH3)3) (X = H or Si) [15].
These observations from the 29Si NMR spectrum gives evidence
of the formation of several products consisting of different silicon
sites which results from both the dehydrocoupling and the hydro-
silylation reactions.
2.2.2. 13C NMR study
2.2. Reaction with the secondary silane, Ph2SiH2
In this case, the hydrosilylation is confirmed by the two peaks
(2.3 and 3.4 ppm) observed due to the formation of Si–C(sp3).
The peak at 50.9 corresponds to the carbon of the methoxy groups
and the aromatic carbons are observed at 125–140 ppm (Fig. 5).
The same procedures as above were used for studying the reac-
tions of the secondary silane (Scheme 3) with stoichiometric quan-
tities of diphenylsilane and alkoxysilane.
2.2.3. 29Si NMR study
In this system, it has been reported that this secondary silane
leads essentially to the dimer (Ph2HSi–SiHPh2) [16] by dehydro-
coupling reaction. There are at least five possible compounds
which may be formed in this reaction. Three compounds may be
obtained consequently to dehydrogenative coupling: the dimer it-
self (Ph2HSi–SiHPh2), then Ph2HSi-SiPh2–CH2–CH2–Si(OMe)3 and
[SiPh2–CH2–CH2–Si(OMe)3]2 resulting from a monohydrosilylation
and a dihydrosilylation of the former. Moreover, the dimers
(Ph2HSi–SiHPh2, and then Ph2HSi–SiPh2–CH2–CH2–Si(OMe)3) may
Four peaks can clearly be seen in the 29Si spectrum, which are
assigned as follows (see Fig. 6):
– The peak at À10.6 ppm is assigned to the completely-substi-
tuted compound resulting from the dihydrosilylation of the ini-
tial secondary silane. This chemical shift is quite similar to that
described for (CH3)2SiPh2 [16].
– The peak at À28.9 ppm is attributed to the silicon atom of the
monohydrosilylated Ph2SiH–CH2–CH2–Si(OMe)3 [13,17].
– The two peaks at À40.6 and À42 ppm correspond to the silicon
atoms bearing the methoxy groups.
– A small peak which is observed at À51.2 ppm may be
attributed to the chemical shift of the monohydrosilylated
and dihydrosilylated dimers (respectively Ph2HSi–SiPh2–
CH2–CH2–Si(OMe)3 and [SiPh2–CH2–CH2–Si(OMe)3]2) [15].
This peak is very weak, suggesting that the hydrosilylation
reaction is favoured over the dehydrocoupling reaction in
this case.
1) Cp2Ti(OPh)2
50°C, 20 min
Ph Ph
Ph Si Si Ph
Ph2SiH2
+
Si(OCH3)3
1 mole eq.
2) rt, 24h
H
1 mole eq.
Si(OCH3)3
Scheme 3. Reaction with the secondary silane, Ph2SiH2.

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J. Garcia et al. / Journal of Organometallic Chemistry 694 (2009) 2427–2433
Fig. 4. 1H NMR spectra of (a) Ph2SiH2, (b) vinylSi(OMe)3, and (c) the reacting mixture of vinylSi(OMe)3 with Ph2SiH2.
Fig. 5. 13C NMR spectrum of the reaction mixture with Ph2SiH2.
2.4.1. 1H NMR study
Fig. 7 shows the 1H NMR spectra of the disilane, the alkoxysi-
lane and the reaction mixture.
2.3. Reaction with the tertiary silane, Ph3SiH
In this case, hydrosilylation does occur, since the NMR spectrum
of the reaction mixture (Fig. 7, spectrum c) exhibits no chemical
shift at around 6 ppm (vinylic protons) whereas Si-CH2 protons ap-
pear at 0.5–1.2 ppm. Moreover, the Si-H signal of the starting di-
It is known that tertiary silanes do not readily undergo dehy-
drocoupling [16b]. However it was of interest to see if hydrosilyla-
tion could occur in this case with the titanocene complex.
The same procedure as above was used with a 1/1 molar
amount of the silane and the alkoxysilane (Scheme 4).
mer disappears completely and
a new signal (4.94 ppm) is
observed. The chemical shift of this Si–H peak is similar to that ob-
served in the case of the secondary silane, Ph2SiH2, and could cor-
respond to the monohydrosilylated compound, Ph2HSi–
SiCH2CH2Si(OMe)3Ph2.
Despite the drastic conditions used (higher reaction tempera-
ture at 70 °C for 24 h) no reaction occurred, and only the two start-
ing reagents were observed by NMR. This confirms that the
titanium complex is not a convenient catalyst for the hydrosilyla-
tion reaction in the case of a bulky tertiary silane. (see Scheme 4).
2.4.2. 13C NMR study
The 13C spectrum of the reaction mixture is presented in Fig. 8
and exhibits Si–C sp3 chemical shifts at 2.34 and 3.52 ppm. The
peak at 51.3 ppm is attributed to the methoxy groups and shifts
associated with the phenylene groups are observed at 125–
140 ppm. These observations give clear evidence that the disilane
can undergo hydrosilylation.
2.4. Reaction with tertiary disilane, Ph2HSi-SiHPh2
Since the secondary silane Ph2SiH2 dimerises to form Ph2HSi–
SiHPh2 it was of interest to investigate if this dimer, which is con-
sidered to be a tertiary silane, could be hydrosilylated (Scheme 5).
If so, then at least two compounds may be obtained in this reaction
with monohydrosilylation and dihydrosilylation of the dimer lead-
ing to Ph2HSi–SiCH2CH2Si(OMe)3Ph2 and [SiCH2CH2Si(OMe)3Ph2]2,
respectively. Again according to the literature, the monohydroge-
nosilane Ph2HSi–SiCH2CH2Si(OMe)3Ph2 can polymerise to form oli-
gosilanes. The same reaction conditions were used as for the
primary and the secondary silanes with stoichiometric (1/1) quan-
tities of the disilane and alkoxysilane.
2.4.3. 29Si NMR study
In this case the 29Si spectrum exhibits several peaks (Fig. 9)
which may be assigned as follows:
– The peak at À28.9 ppm is attributed to the monohydrogeno sil-
icon atom of the Ph2SiH–SiPh2[CH2–CH2–Si(OMe)3] [13,17].

J. Garcia et al. / Journal of Organometallic Chemistry 694 (2009) 2427–2433
2431
Fig. 6. 29Si NMR spectrum of the reaction mixture with Ph2SiH2.
– The peaks at À39.9 and À42.1 ppm are assigned to the silicon
atoms bearing three methoxy groups.
Ph
Ph Si
Cp2Ti(OPh)2
Ph
Ph3SiH
+
Si(OCH3)3
1 mole eq.
– The peak at À50.6 ppm is attributable to the monohydrosilylat-
ed and dihydrosilylated dimers (Ph2HSi–SiPh2–CH2–CH2–
Si(OMe)3 and [SiPh2–CH2–CH2–Si(OMe)3]2, respectively) and
also to the silicon atoms of the oligomers which may form
[17]. Indeed this peak is relatively intense compared to the cor-
responding feature in the spectrum of the secondary silane. It
may be considered that oligomerisation of the dimer occurs
more readily than with the secondary silane in which the dehy-
drocoupling is somehow inhibited due to the formation of
Ph2Si–[CH2–CH2–Si(OMe)3] by dihydrosilylation.
70°C, 24h
1 mole eq.
Si(OCH3)3
Scheme 4. Reaction with the tertiary silane, Ph3SiH.
1) Cp2Ti(OPh)2
50°C, 20 min
Ph Ph
Ph Si Si Ph
Ph Ph
Ph Si
H
+
Si(OCH3)3
1 mole eq.
Si Ph
2) rt, 24H
H
H
1 mole eq.
Si(OCH3)3
Scheme 5. Reaction with the tertiary di-silane, Ph2HSi–SiHPh2.
– Moreover no peak at À10.7 ppm is observed which is expected
since no dihydrosilylation can occur.
Fig. 7. 1H NMR spectra of (a) (Ph2SiH)2, (b) vinylSi(OMe)3 and (c) the reaction mixture of vinylSi(OMe)3 with (Ph2SiH)2.

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J. Garcia et al. / Journal of Organometallic Chemistry 694 (2009) 2427–2433
son (France). 1H and 13C NMR solution spectra were recorded on
Bruker AC-200 spectrometers at 200 and 50 MHz, respectively.
29Si NMR solution spectra were recorded on a Bruker AC-250 or
AC-400 and CDCl3 was used as a solvent. All chemical shifts are re-
ported as d values in parts per million relative to Me4Si (d 0 ppm for
1H).
4.1.1. Dimerisation of Ph2SiH2 [16]
Ph2SiH2 (2.00 g, 10.9 mmol) and Cp2Ti(OPh)2 (8.0 mg, 2.2 lmol)
were mixed in a flask under argon. The mixture, upon heating at
100 °C, turned dark blue and hydrogen was evolved. After 15 h,
the mixture was cooled to room temperature. Crystallisation from
pentane gave 0.85 g of Ph2SiH2. (Yield 22%. mp = 79 °C (literature
[16] 78 – 80 °C. 1H NMR (CDCl3): d = 7.56–7.35 (m, 20H, Ph-H),
5.27 (s, 2H, SiH)).
Fig. 8. 13C NMR spectrum of the reaction mixture with (Ph2SiH)2.
4.2. Reaction of the phenylsilanes and vinyltrimethoxysilane with
Cp2Ti(OPh)2
4.2.1. PhSiH3 + vinyltrimethoxysilane
PhSiH3 (300 mg, 2.77 mmol), vinyltrimethoxysilane (411 mg,
2.77 mmol) and Cp2Ti(OPh)2 (30 mg, 0.083 mmol) were mixed in
a flask under argon. The solution was heated to 50 °C. After
20 min at 50 °C, the solution colour changed from yellow to dark
blue and H2 was released, indicating the commencement of the
dehydrocondensation reaction. The solution was stirred at room
temperature for 24 h until the vinylic protons were no longer evi-
dent in the 1H NMR spectrum, indicating that the hydrosilylation
was complete.
1H NMR (CDCl3): d = 0.5–1.2 (m, PhSiCH2CH2Si), 3.51–3.63 (m,
OCH3), 4.85 (t, Ph(CH2CH2Si(OCH3)3)SiHSi), 4.95 (s, Si–SiH), 7.32–
7.81 (m, Ph-H); 13C NMR (CDCl3): d = 0–3.7 (SiCH2), 50.4 (OCH3),
Fig. 9. 29Si NMR spectrum of the reaction mixture with Ph2SiH2.
127–136 (Ph and catalyst); 29Si NMR (CDCl3): d = À50.2 (PhSi (H)(-
*
Si/H)CH2CH2Si(OCH3)3), À41.9 and À40.6 (Si(OCH3)3), À16.4
*
*
3. Conclusions
(PhSi (Si/H)(CH2CH2Si(OCH3)3)2), À2.9 (PhSi [CH2CH2Si(OCH3)3]3);
Anal. Found for C5.27H8.47O1.33Ti0.02Si: C, 51.79; H, 6.98; O, 17.43;
Ti, 0.84; Si, 22.96%.
In conclusion, we report a one-pot synthesis of functional poly-
silanes using CP2Ti(OPh)2 as catalyst. The latter promoted the
dehydrogenative coupling of the silanes which simultaneously re-
act with vinyltrimethoxysilane via a hydrosilylation reaction.
These reactions readily occur with primary and secondary silanes,
where the dehydrocoupling step is favourable. It does not appear
to occur with tertiary silanes, which do not undergo any of the
two reactions even under more drastic conditions. However, it
was shown that the dimer Ph2HSi–SiHPh2 bearing the Si–Si bond
undergoes the hydrosilylation reaction and oligomerisation. From
these studies it appears that the formation of Si–Si bonds through
the catalysed dehydrocoupling of hydrogenosilanes is the key step
favouring the simultaneous hydrosilylation reaction. Although it is
possible that the Si–Si bond may facilitate the hydrosilylation reac-
tion, it is also possible that the disilane may first react directly with
the titanium catalyst to generate sufficiently reactive species that
subsequently participate in the hydrosilylation reactions.
4.2.2. Ph2SiH2 + vinyltrimethoxysilane
Ph2SiH2 (300 mg, 1.63 mmol), vinyltrimethoxysilane (242 mg,
1.63 mmol) and Cp2Ti(OPh)2 (18 mg, 0.049 mmol) were mixed in
a flask under argon. The solution was heated to 50 °C. After
20 min at 50 °C, the colour of the solution changed from yellow
to dark blue with evolution of H2. The solution was stirred at
50 °C for 24 h until the vinylic protons were no longer evident in
the 1H NMR spectrum, indicating that the hydrosilylation was
complete.
1H NMR (CDCl3): d = 0.5–1.2 (m, Ph2SiCH2CH2Si), 3.49–3.63 (m,
OCH3), 4.92 (m, SiH), 7.36–7.68 (m, Ph-H); 13C NMR (CDCl3): d = 2.3
and 3.4 (SiCH2CH2Si), 50.9–51.1 (OCH3), 127.8–134.8 (Ph and cata-
lyst); 29Si NMR (CDCl3): d = À51.2 (Ph2(H)Si Si(Ph2)CH2CH2-
*
Si(OCH3)3),
(Ph2(H)SiSi (Ph2)CH2CH2Si(OCH3)3),
Si(OCH3)3)2); Anal. Found for C9.05H10.8O1.44Ti0.02Si: C, 63.28; H,
6.34; O, 13.45; Ti, 0.58; Si, 16.35%.
À42
and
À40.6
(Si(OCH3)3),
À28.9
*
*
À10.6
(Ph2Si (CH2CH2-
4. Experimental
4.1. General and techniques
4.2.3. (Ph2SiH)2 + vinyltrimethoxysilane
(Ph2SiH)2 (150 mg, 0.41 mmol), vinyltrimethoxysilane (61 mg,
0.41 mmol) and Cp2Ti(OPh)2 (5 mg, 0.012 mmol) were mixed in a
flask under argon. The solution was heated to 50 °C. After 20 min
at 50 °C, the colour of the solution changed from yellow to dark
blue with evolution of H2. The solution was stirred at 50 °C for
24 h until the vinylic protons were no longer evident in the 1H
NMR spectrum, indicating that the hydrosilylation was complete.
1H NMR (CDCl3): d = 0.5–1.23 (m, Ph2SiCH2CH2Si), 3.34–3.63 (m,
OCH3), 4.9 (s, SiH), 7.29–7.56 (m, Ph-H); 13C NMR (CDCl3):
All reactions were carried out under a nitrogen atmosphere
using vacuum line and Schlenk techniques. The reagents were pur-
chased from Aldrich or Alfa Aeser. Karstedt and Speier catalysts
were obtained from ABCR and Aldrich, respectively. Cp2Ti(OPh)2
was synthesised according to the literature [6].
Melting points were determined on an electrothermal appara-
tus (IA9000 series) and are uncorrected. Elemental analyses were
undertaken by the ‘‘Service Central d’Analyse du CNRS” at Vernai-

J. Garcia et al. / Journal of Organometallic Chemistry 694 (2009) 2427–2433
2433
(d) K. Matyjaszewski, Y.L. Chen, H.K. Kim, in: M. Zeldin, K.J. Wynne, H.R.
Alcock (Eds.), Inorganic and Organometallic Polymers, Vol. 360, Am. Chem.
Soc., Washington, DC, 1988 (Chapter 6).
d = 2.2 and 4.2 (SiCH2CH2Si), 50.3 and 50.7 (OCH3), 126.9–137.3 (Ph
and catalyst); 29Si NMR (CDCl3) : d = À50.6 (Ph2(H)Si
*-
Si(Ph2)CH2CH2Si(OCH3)3), À42.1 and À39.9 (Si(OCH3)3), À28.9
[3] (a) E. Samuel, J.F. Harrod, J. Am. Chem. Soc. 106 (1984) 1859–1860;
(b) C. Aitken, J.F. Harrod, E. Samuel, J. Organomet. Chem. 279 (1985) C11–C13;
(c) C. Aitken, J.P. Barry, F. Gauvin, J.F. Harrod, A. Malek, D. Rousseau,
Organometallics 8 (1989) 1732–1736.
*
(Ph2(H)SiSi (Ph2)CH2CH2Si(OCH3)3); Anal. Found for C9.78H9.98O0.74-
Ti0.01Si: C, 69.83; H, 5.98; O, 7.07; Ti, 0.43; Si, 16.69%.
[4] (a) H.G. Woo, T.D. Tilley, J. Am. Chem. Soc. 111 (1989) 8043–8044;
(b) T.D. Tilley, Acc. Chem. Res. 26 (1993) 22–29.
[5] (a) J.Y. Corey, Adv. Silicon Chem. 1 (1991) 327–387;
(b) J.Y. Corey, X.H. Zhu, J. Organomet. 439 (1992) 1.
[6] K. Andrä, J. Organomet. Chem. 11 (1968) 567.
[7] S. Bourg, R.J.P. Corriu, M. Enders, J.J.E. Moreau, Organometallics 14 (1995) 564–
566.
[8] R. Shankar, A. Joshi, J. Organomet. Chem. 691 (2006) 3310.
[9] (a) J.F. Harrod, S.S. Yun, Organometallics 6 (1987) 1381;
(b) M.R. Kesti, M. Abdulrahman, R.M. Waymouth, J. Organomet. Chem. 417
(1992) C12;
4.2.4. Ph3SiH + vinyltrimethoxysilane
Ph3SiH (100 mg, 0.38 mmol), vinyltrimethoxysilane (57 mg,
0.38 mmol) and Cp2Ti(OPh)2 (4.5 mg, 0.011 mmol) were mixed in
a flask under argon. Although the solution was heated at 70 °C
for 24 h. no reaction occurred.
Acknowledgment
(c) J.Y. Corey, X.H. Zhu, Organometallics 11 (1992) 672–683;
(d) L. Bareille, S. Becht, J.L. Cui, P. Le Gendre, C. Moïse, Organometallics 24
(2005) 5802.
The authors are grateful to the CNRS and the Ministère de la
Recherche et de la Technologie, ACI nanosciences-nanotechnolo-
gies for fundings. M.W.C.M. would like to thank J.R. Bartlett for
fruitful discussions and help.
[10] Q. Wang, J.Y. Corey, Can. J. Chem. 78 (2000) 1434–1440.
[11] Y.-L. Hsiao, R.M. Waymouth, J. Am. Chem. Soc. 116 (1994) 9779.
[12] J.P. Kintzinger, H. Marsmann, in: P. Diehl, E. Fluck, R. Kosfeld (Eds.), NMR 17
Basic Principles and Progress, Grundlagen der Fortschritte, Oxygen-17 and
Silicon-29, Springer-Verlag, Berlin, Heidelberg, New York, 1981.
[13] T. Tarayama, I. Ando, Bull. Chem. Soc. 60 (1987) 3125–3129.
[14] K.G. Sharp, P.A. Sutor, E.A. Williams, J.D. Cargioli, T.C. Farrar, K. Ishibitsu, J. Am.
Chem. Soc. 98 (1976) 1977–1979.
[15] C. Chatgilialoglu, A. Guerrini, M. Lucarini, G.F. Pedulli, P. Carrozza, G.D. Roit, V.
Borzatta, V. Lucchini, Organometallics 17 (1998) 2169–2176.
[16] (a) J.S. Winkler, H.J. Gilman, J. Org. Chem. 26 (1961) 1265;
(b) L.S. Chang, J.Y. Corey, Organometallics 8 (1989) 1885.
[17] E. Hengge, M. Weinberger, C. Jammegg, J. Organomet. Chem. 410 (1991) C1–
C4.
References
[1] (a) R. West, J. Organomet. Chem. 300 (1986) 327;
(b) R.D. Miller, J. Michl, J. Organomet. Chem. 89 (1989) 1359;
(c) C.J.M. Ziegler, Mol. Cryst. Liq. Cryst. 190 (1990) 265.
[2] (a) R.H. Baney, J.M. Gaul, T.K. Hilty, Organometallics 2 (1983) 859;
(b) C. Biran, M. Bordeau, P. Pons, M.P. Leyer, J. Dunoguès, J. Organomet. Chem.
332 (1990) C17;
(c) K. Sakamoto, K. Ohata, M. Mirata, N. Nakajima, H. Sakurai, J. Am. Chem. Soc.
111 (1989) 7641;