One-pot synthesis of poly(alkoxysilane)s by Si-Si/Si-O dehydrocoupling of silanes with alcohols using Group IV and VIII metallocene complexes

Article abstract of DOI:10.1016/S0022-328X(03)00469-8

Si-Si/Si-O dehydrocoupling reactions of silanes with alcohols (1:1.5 mole ratio), catalyzed by Cp₂MCl₂/Red-Al (M=Ti, Zr) and Cp₂M′ (M′=Co, Ni), produced poly(alkoxysilane)s in one-pot in high yield. The silanes included p-X-C₆H₄SiH₃ (X=H, CH₃, OCH₃, F), PhCH₂SiH₃, and (PhSiH₂)₂. The alcohols were MeOH, EtOH, ⁱPrOH, PhOH, and CF₃(CF₂) ₂CH₂OH. The weight average molecular weight of the poly(alkoxysilane)s ranged from 600 to 8000. The dehydrocoupling reactions of phenylsilane with ethanol (1:1.5 mole ratio) using Cp₂HfCl₂/Red-Al and phenylsilane with ethanol (1:3 mole ratio) using Cp₂TiCl₂/Red-Al gave only triethoxyphenylsilane as product.

Full text of DOI:10.1016/S0022-328X(03)00469-8

Journal of Organometallic Chemistry 685 (2003) 93ꢁ98
/
www.elsevier.com/locate/jorganchem
One-pot synthesis of poly(alkoxysilane)s by SiÃ
/
Si/SiÃ
/
O
dehydrocoupling of silanes with alcohols using Group IV and VIII
metallocene complexes
Bo-Hye Kim, Myong-Shik Cho, Mi-Ae Kim, Hee-Gweon Woo *
Department of Chemistry and Institute of Basic Sciences, Chonnam National University, Kwangju 500-757, South Korea
Received 9 January 2003; received in revised form 26 April 2003; accepted 22 May 2003
Abstract
SiÃ
/
Si/SiÃ
/
O dehydrocoupling reactions of silanes with alcohols (1:1.5 mole ratio), catalyzed by Cp2MCl2/Red-Al (Mꢀ
/
Ti, Zr) and
Cp2M? (M?ꢀ
/
Co, Ni), produced poly(alkoxysilane)s in one-pot in high yield. The silanes included p-XÃC6H4SiH3 (Xꢀ
/
/H, CH3,
i
OCH3, F), PhCH2SiH3, and (PhSiH2)2. The alcohols were MeOH, EtOH, PrOH, PhOH, and CF3(CF2)2CH2OH. The weight
average molecular weight of the poly(alkoxysilane)s ranged from 600 to 8000. The dehydrocoupling reactions of phenylsilane with
ethanol (1:1.5 mole ratio) using Cp2HfCl2/Red-Al and phenylsilane with ethanol (1:3 mole ratio) using Cp2TiCl2/Red-Al gave only
triethoxyphenylsilane as product.
# 2003 Elsevier Science B.V. All rights reserved.
Keywords: Hydrosilanes; Dehydrocoupling; Metallocene; Catalyst; Poly(alkoxysilane)
1. Introduction
polysilanes prepared by Wurtz coupling, particularly for
phenyl-substituted polysilanes [7ꢁ10]. Recently devel-
/
Polysilanes have recently attracted considerable atten-
tion due to their peculiar electronic and photophysical
properties as well as their potential applications in
microlithography [1], in ceramics [2], as photoconduct-
ing polymers [3], and as third-order nonlinear optical
materials [4]. The unique properties of polysilanes stem
from the extensive delocalization of s-electrons along
the silicon backbone and depend on the nature of the
substituents attached to the polymer backbone, the
polymer conformation, and the polymer molecular
weight [5]. Polysilanes are generally prepared by Wurtz
coupling of dichlorosilanes using sodium metal in
refluxing hydrocarbon solvents such as toluene [5].
The introduction of functionality onto the polymer
chain is quite limited due to the harsh reaction condi-
tions employed in the reductive coupling reaction [6].
Some recent success has been achieved in functionalizing
oped transition-metal mediated dehydrocoupling synth-
eses of polysilanes provide exciting opportunities for the
synthesis of polymers with defined structure and func-
tionality [11]. One of the appealing characteristics of
polysilanes synthesized by the catalytic SiÃ
coupling of primary silanes is the reactive SiÃ
functionality in the backbone of the polysilanes. The
SiÃH functional group can be transformed to other
/Si dehydro-
/H
/
useful functional groups by simple chemical reactions.
Very recently, Waymouth and co-workers [12,13] re-
ported a free-radical method for selectively substituting
the backbone SiÃ
radical chlorination of polyphenylsilane [Ã
with CCl4 afforded poly(chlorophenylsilane) [Ã
Si(Cl)PhÃ]n, which was subsequently reacted with
nucleophiles to produce a new polysilane [ÃSi(X)PhÃ
(XꢀMe, OMe).
A wide range of catalysts have been reported for SiÃ
/H bonds of polyphenylsilane. Free-
/
Si(H)PhÃ
/
]
n
/
/
/
/
]
n
/
/O
dehydrocoupling of OH-containing compounds with
silanes [14,15]. These catalysts include acids, bases,
and both homogeneous and heterogeneous transition
* Corresponding author. Tel.: ꢂ
3389.
E-mail address: hgwoo@chonnam.ac.kr (H.-G. Woo).
/
82-62-530-3378; fax: ꢂ82-62-530-
/
0022-328X/03/$ - see front matter # 2003 Elsevier Science B.V. All rights reserved.
doi:10.1016/S0022-328X(03)00469-8

94
B.-H. Kim et al. / Journal of Organometallic Chemistry 685 (2003) 93ꢁ98
/
metal catalysts. Bedard and Corey [16] carried out a
survey of the dehydrocoupling of a range of organosi-
lanes and alcohols under the influence of Cp2TiCl2/
2nBuLi. The transition metal complexes of Group VIII
(Ni, Co, Rh, Pd, Ir, Pt etc.) have been extensively
applied for the catalytic dehydrocoupling of hydrosi-
ð1Þ
ð2Þ
lanes with various nucleophilic reagents [17ꢁ21]. In the
/
presence of Raney nickel and Pd/C catalysts, dehydro-
coupling of triallylsilane with excess alcohol produced
trialkoxysilane [22]. SiÃ/Si dehydrocoupling of hydro-
silanes with late transition metal catalysts produced a
mixture of oligomers along with a significant amount of
redistributed by-products [23].
The weight average molecular weight of the produced
polymers ranged from 700 to 2800. In the SiÃSi
dehydrocoupling of phenylsilane catalyzed by
Cp2TiCl2/Red-Al, 30ꢁ40% of cyclic formation was
reported [11]. By comparison, small amount (Â3%;
judged by Gel permeation chromatography (GPC)
analysis) of cyclic formation was observed in the SiÃ
O dehydrocoupling of phenylsilane with ethanol
/
In spite of numerous reported studies on the alcoho-
lysis of hydrosilanes and on the dehydropolymerization
of silanes in the presence of transition metal catalysts, to
our knowledge there is no single report regarding the
/
/
/
one-pot synthesis of poly(alkoxysilane)s by direct SiÃ
SiÃO dehydrocoupling of hydrosilanes with alcohols.
Poly(alkoxysilane)s can be used as precursors for
preparing interesting polysilaneꢁsiloxane hybrids by
solꢁgel methods [24]. Herein we report a mild and
/Si/
Si/SiÃ
/
/
(1:1.5 mole ratio) catalyzed by Cp2TiCl2/Red-Al. How-
ever, no appreciable cyclic formation was found in the
O dehydrocoupling of phenylsilane with etha-
nol (1:1.5 mole ratio) catalyzed by Cp2ZrCl2/Red-Al.
The 1H-NMR spectra of the poly(alkoxysilane)s showed
/
SiÃ
/
Si/SiÃ
/
/
simple one-pot procedure for the introduction of alkoxy
groups (OMe, OEt, OiPr, OCH2(CF2)2CF3) onto the
polysilane backbone with Group IV metallocene
no appreciable SiÃ
/
H resonances. Nonetheless, the IR
spectra of the poly(alkoxysilane)s exhibited an extremely
weak nSiH band around 2100 cmꢃ1. Therefore, we can
assume that the polymers are almost fully substituted
poly(alkoxysilane)s. In the catalytic reaction of hydro-
silane and ethanol with Cp2TiCl2/Red-Al catalyst, as
expected, the mole ratio of hydrosilane to alcohol
largely affected the degree of alkoxy-substitution and
the weight average molecular weight (Mw) of the
polymer products. It is interesting to note that reaction
time also affected the degree of substitution and Mw as
Cp2MCl2 (Mꢀ
VIII metallocene Cp2M? (M?ꢀ
/
Ti, Zr)/Red-Al combination and Group
Co, Ni) catalysts.
/
2. Results and discussion
2.1. SiÃ
/
Si/SiÃ
/
O dehydrocoupling of silanes and alcohols
catalyzed by Cp2MCl2/Red-Al (Mꢀ
/Ti, Zr)
shown in Table 1. In the SiÃ
/
Si/SiÃ
/
O dehydrocoupling of
For 48 h at 50 8C, a 1.5:1 mole ratio of alcohols
i
phenylsilane with ethanol (1:1.5 mole ratio) catalyzed by
(EtOH, PrOH) and hydrosilanes [p-X-C6H4SiH3 (Xꢀ
/
1
Cp2TiCl2/Red-Al, Â
scopy) of ethoxy-substituted polymer with 960 of Mw
was obtained for 24 h of reaction time where as Â100%
/70% (judged by H-NMR spectro-
H, F, CH3, OCH3), PhSiH3, PhCH2SiH3, PhSiH2-
SiH2Ph] reacted in the presence of 2 mol% of
/
Cp2MCl2/Red-Al (MꢀTi, Zr) catalyst to produce
/
of ethoxy-substituted polymer with 1220 of Mw was
obtained for 480 h of reaction time. In terms of the
catalyst, the degree of polymerization decreased in the
poly(alkoxysilane)s along with the respective trialkox-
ysilane as a minor product. The reaction of phenylsilane
and ethanol with Cp2TiCl2/Red-Al catalyst produced
30% substituted poly(ethoxyphenylsilane) (mole ratio of
1:0.5) in 91% isolated yield and fully substituted
poly(ethoxyphenylsilane) (mole ratio of 1:1.5) in 76%
yield (Eq. 1). The only isolated product from the
dehydrocoupling reaction of a 1:3 mole ratio of PhSiH3
and ethanol with Cp2TiCl2/Red-Al catalyst was
PhSi(OEt)3. The dehydrocoupling reaction of PhSiH3
and ethanol (1:1.5 mole ratio) with Cp2HfCl2/Red-Al
catalyst did not result in polymerization, with the only
product being PhSi(OEt)3 (Eq. 2). The results of the
reactions of hydrosilanes and alcohols, catalyzed by
order Tiꢀ
tions of PhSiH3 with EtOH (1:1.5 mole ratio) using
Cp2MCl2/Red-Al (MꢀTi, Zr) were performed for 5
/
Zrꢁ/Hf. When the dehydrocoupling reac-
/
days at ambient temperature, the only isolated product
was triethoxyphenylsilane.
2.2. SiÃ
/
Si/SiÃ
/
O dehydrocoupling of silanes and alcohols
Co, Ni)
catalyzed by Cp2M? (M?ꢀ
/
The SiÃ
alcohols with 2 mol.% of Cp2M? (M?ꢀ
poly(alkoxysilane)s at room temperature in high yields
/
Si/SiÃ/O dehydrocoupling of hydrosilanes and
Cp2MCl2/Red-Al (Mꢀ
/
Ti, Zr, Hf), are summarized in
/Co, Ni) yielded
Table 1.

B.-H. Kim et al. / Journal of Organometallic Chemistry 685 (2003) 93ꢁ
/98
95
Table 1
Results for the reactions of hydrosilane and alcohol with Group IV metallocene-based Cp2MCl2/Red-Al combination catalysts
Silane:Alcohol (mole ratio)
Catalyst a [M]
Polymer isolated yield (%)
Mol wt. b
Mw
Mn
Mw/Mn
PhSiH3:EtOH (1:0.5)
PhSiH3:EtOH (1:1.5)
PhSiH3:EtOH (1:1.5) c
PhSiH3:EtOH (1:3)
Ti
Ti
Ti
Ti
Zr
Hf
Ti
Ti
Ti
Ti
Zr
Ti
Zr
Ti
Zr
91
76
1540
1220
960
1180
580
1.3
2.1
1.6
50
600
PhSi(OEt)3 (98)
76
ꢁ/
1030
ꢁ/
690
ꢁ/
1.5
PhSiH3:EtOH (1:1.5)
PhSiH3:EtOH (1:1.5)
(PhSiH2)2:EtOH (1:2)
PhCH2SiH3:EtOH (1:1.5)
PhSiH3:i PrOH (1:1.5)
PhSi(OEt)3 (43)
ꢁ/
ꢁ/
670
360
ꢁ/
70
77
64
82
87
76
74
79
83
1620
1010
750
1.7
2.8
1.3
1.2
1.1
1.4
1.1
1.3
1.4
570
Poly(p-FÃ
Poly(p-FÃ
Poly(p-CH3Ã
Poly(p-CH3Ã
Poly(p-OCH3Ã
Poly(p-OCH3Ã
/
C6H4SiH3):EtOH (1:1.5)
2300
1120
2800
1400
2560
1310
1920
1020
2000
1270
1970
940
/C6H4SiH3):EtOH (1:1.5)
/
C6H4SiH3):EtOH (1:1.5)
C6H4SiH3):EtOH (1:1.5)
/
/
C6H4SiH3):EtOH (1:1.5)
C6H4SiH3):EtOH (1:1.5)
/
Heated at 50 8C in neat for 48 h.
a
[M]/[Si]ꢀ0.02.
Measured by GPC in THF (vs. polystyrene).
Heated at 50 8C in neat for 24 h.
/
b
c
after workup and column chromatography. The results
of these reactions are given in Table 2.
As in the case of Group IV metallocene catalysts, the
mole ratio of hydrosilane to alcohol significantly
affected the degree of alkoxy-substitution and the
polymer molecular weights in the dehydrocoupling
1H-NMR spectra of the polymers prepared from the
SiÃ
/
Si/SiÃ
/
O
dehydrocoupling reaction of silanes
(PhSiH3, PhCH2SiH3, PhSiH2SiH2Ph) and alcohols
reaction of silane and alcohol with Cp2M? (M?ꢀCo,
/
i
ROH (Rꢀ
showed no appreciable SiÃ
of all the polymers exhibited a strong nSiÃO band around
1100ꢁ
1000 cmꢃ1. The FT-IR spectra reflected the
/
Et, Pr) with Cp2Co and Cp2Ni catalysts
Ni). The reaction of phenylsilane and ethanol (1:0.5
mole ratio) produced 40% partially substituted polymer.
The dehydrocoupling reaction of phenylsilane and
ethanol (1:3 mole ratio) produced triethoxyphenylsilane
and unidentified materials as minor products (Eq. 3).
The unidentified materials were believed to be by-
products from the redistribution of aryl or alkoxy
groups (e.g., Ph2Si(OEt)2, Ph3SiOEt). It has been
/H resonances. The IR spectra
/
disappearance of the nSià H band. The weight average
molecular weight of the produced polymers ranged from
600 to 8100. The GPC characterization data of these
reactions are given in Table 3.
Table 2
Results for the reactions of hydrosilane and alcohol with Group VIII metallocene Cp2M? catalysts
Silane:Alcohol (mole ratio)
Catalyst a [M?]
Reaction time (h)
Product (isolated% yield)
PhSiH3:EtOH (1:0.5)
PhSiH3:EtOH (1:1.5)
PhSiH3:EtOH (1:3)
Co
Co
Co
Ni
23
16
24
32
10
20
26
22
16
10
24
24
24
poly(ethoxyphenylsilane) (83)
poly(ethoxyphenylsilane) (87)
PhSi(OEt)3 (92)
PhSiH3:EtOH (1:1.5)
PhSiH3:MeOH (1:1.5)
PhSiH3:i PrOH (1:1.5)
PhSiH3:PhOH (1:1.5)
PhSiH3:CF3(CF2) 2CH2OH (1:1.5)
(PhSiH2)2:EtOH (1:2)
(PhSiH2)2:MeOH (1:2)
PhCH2SiH3:EtOH (1:1.5)
PhCH2SiH3:MeOH (1:1.5)
PhSiH3:EtOH (1:3)
poly(ethoxyphenylsilane) (78)
poly(methoxyphenylsilane) (81)
poly(isopropoxyphenylsilane) (81)
poly(phenoxyphenylsilane) (88)
poly(alkoxyphenylsilane) (75)
poly(ethoxyphenylsilane) (92)
poly(methoxyphenylsilane) (84)
poly(methoxyphenylsilane) (64)
poly(methoxyphenylsilane) (68)
PhSi(OEt)3 (92)
Co
Co
Co
Co
Co
Co
Co
Co
Co
Stirred at ambient temperature in neat until the reaction mixture became rigid.
a
[M]/[Si]ꢀ0.02.
/

96
B.-H. Kim et al. / Journal of Organometallic Chemistry 685 (2003) 93ꢁ98
/
Table 3
GPC characterization of hydrosilane and alcohol with Group VIII
metallocene Cp2M? catalysts
Silane:Alcohol (ratio)
Catalyst a
Mol wt. b
[M?]
Mw Mn Mw/
Mn
PhSiH3:EtOH (1:0.5)
PhSiH3:EtOH (1:1.5)
PhSiH3:EtOH (1:1.5)
PhSiH3:MeOH (1:1.5)
PhSiH3:i PrOH (1:1.5)
PhSiH3:PhOH (1:1.5)
PhSiH3:CF3(CF2)2CH2OH
(1:1.5)
Co
Co
Ni
2010 1510 1.3
1470 790 1.9
610 580 1.1
5900 1110 5.4
3800 2400 1.6
5260 660 8.0
2090 520 4.0
Co
Co
Co
Co
Fig. 1. UV spectra of
poly(ethoxyphenylsilane).
Ã
/
(PhSiX)n Ã: (a) polyphenylsilane; (b)
/
(PhSiH2)2:EtOH (1:2)
(PhSiH2)2:MeOH (1:2)
PhCH2SiH3:EtOH (1:1.5)
PhCH2SiH3:MeOH (1:1.5)
Co
Co
Co
Co
3910 2190 1.8
8130 2310 3.5
3320 1970 1.7
2870 820 3.5
2.4. Conclusions
Stirred at ambient temperature in neat until the reaction mixture
became rigid.
Poly(alkoxysilane)s were prepared in high yields from
the SiÃSi/SiÃO dehydrocoupling reactions of silanes
with alcohols (1:1.5 mole ratio) in the presence of
Cp2MCl2/Red-Al (MꢀTi, Zr) and Cp2M? (M?ꢀCo,
a
/
/
[M]/[Si]ꢀ
/
0.02.
b
Measured with GPC (vs. polystyrene) in THF.
/
/
reported that the dehydrocoupling of hydrosilanes with
late transition metal catalysts produced a mixture of
oligomers along with significant amounts of redistribu-
tion products [23].
Ni) catalyst. Thus, this is a mild and one-pot procedure
with considerable synthetic flexibility for the prepara-
tion of a wide variety of functionalized polysilanes.
3. Experimental
2.3. UV absorption spectrum of
poly(ethoxyphenylsilane)
3.1. General procedures and materials
The UV absorption spectrum of polyphenylsilane
All reactions and manipulations were carried out
under prepurified nitrogen atmosphere using Schlenk
techniques. Dry, oxygen-free solvents were employed
throughout. All glasswares were flamed-dried before
use. Infrared spectra were obtained using a Nicolet 520
contains a weak transition at 297 nm (oSiÃSi
cmꢃ1 Mꢃ1). Substitution of the SiÃ
H group with a
SiÃOEt group resulted in a red shift of 45 nm and an
increase in the extinction coefficient (Fig. 1). The
differences in the lmax for the ÃH and ÃOEt substituents
ꢀ/2062
/
/
/
/
FT-IR or a Perkinꢁ
meter. Electronic spectra were acquired using an IBM
9420 UVꢁvis spectrophotometer. Proton NMR spectra
/Elmer 1600 Series FT-IR spectro-
are likely a result of an electronic perturbation of the
silicon backbone by the ethoxy substituent. The lone-
pair electrons on the oxygen substituent might be
expected to perturb the electronic structure of the
polymer backbone by destabilizing the HOMO more
than the LUMO, leading to a decrease of the transition
energy.
/
were recorded on a Varian Gemini 300 spectrophot-
ometer using CDCl3/CHCl3 as a reference at 7.24 ppm
downfield from Me4Si. GPC was carried out on a
Waters Millipore GPC liquid chromatograph. The
calibrant (monodisperse polystyrene) and the sample
(3)

B.-H. Kim et al. / Journal of Organometallic Chemistry 685 (2003) 93ꢁ
/98
97
were dissolved in THF and separately eluted from an
Ultrastyragel GPC column series (sequence 500, 103,
3.2.2. Reaction of PhSiH3 and EtOH ([Si]:[EtOH]ꢀ
1:1.5) catalyzed by Cp2TiCl2/Red-Al
Off-white powder, yield 76%, Mwꢀ1220, Mnꢀ580.
IR (KBr pellet): 3067, 3047, 2924, 2162, 1962, 1823,
1593, 1429, 1127, 1040, 850, 738. 1H-NMR (CDCl3, 300
/
4
5
˚
10 , 10 A columns). Molecular weights were extrapo-
lated from the calibration curve derived from the
polystyrene standard. Data analyses were carried out
using a Waters Data Module 570. Cp2TiCl2, Cp2ZrCl2,
Cp2HfCl2, Red-Al, Cp2Co, and Cp2Ni were purchased
from Aldrich Chemical Co and were used as received.
Methanol, ethanol, isopropyl alcohol, phenol and 1,2,3-
heptafluorobuthanol were dried according to the litera-
/
/
MHz): d 1.04ꢁ
/
1.18 (br, OCH2CH3), 3.10ꢁ
/
3.65 (br,
OCH2CH3), 6.80ꢁ
/
7.80 (br, Ph).
3.2.3. Reaction of PhSiH3 and EtOH ([Si]:[EtOH]ꢀ
/
ture procedure [25]. The p-XÃ
CH3, OCH3) compounds were obtained by the reaction
p-XÃC6H4MgBr with Si(OEt)4, respectively, in THF.
The p-XÃC6H4SiH3 reagents were prepared by reduc-
tion of the p-XÃC6H4Si(OEt)3 with LiAlH4 in diethyl
ether.
/
C6H4Si(OEt)3 (XꢀH, F,
/
1:3) catalyzed by Cp2TiCl2/Red-Al
Clear oil, yield 95%. IR (KBr pellet): 3067, 3032,
2919, 1961, 1731, 1594, 1429, 1388, 1301, 1152, 947, 789.
/
/
1H-NMR (CDCl3, 300 MHz): d 1.22ꢁ
/
1.27 (t, Jꢀ
3.91 (quartet, Jꢀ7.0 Hz, 2H,
7.41 (m, 3H, Ph), 7.66ꢁ7.69 (m, 2H,
/
7.0
/
Hz, 3H, OCH2CH3), 3.84ꢁ
OCH2CH3), 7.36ꢁ
Ph).
/
/
/
/
3.2. Synthesis of poly(alkoxysilane)s with Group IV
metallocene combination catalysts
3.2.4. Reaction of PhSiH3 and EtOH ([Si]:[EtOH]ꢀ
/
1:1.5) catalyzed by Cp2HfCl2/Red-Al
Clear oil, yield 43%. IR (KBr pellet): 3067, 3032,
2919, 1961, 1731, 1594, 1429, 1388, 1301, 1152, 947, 789.
3.2.1. General procedure for the reaction of PhSiH3 and
1H-NMR (CDCl3, 300 MHz): d 1.22ꢁ
/
1.27 (t, Jꢀ
3.91 (quartet, Jꢀ7.0 Hz, 2H,
7.41 (m, 3H, Ph), 7.66ꢁ7.69 (m, 2H,
/
7.0
EtOH ([Si]:[EtOH]ꢀ/1:1.5) catalyzed by Cp2ZrCl2/
Hz, 3H, OCH2CH3), 3.84ꢁ
OCH2CH3), 7.36ꢁ
Ph).
/
/
Red-Al
/
/
To a Schlenk flask containing Cp2ZrCl2 (0.01 g, 0.03
mmol) and Red-Al (0.01 ml, 0.03 mmol; 3.4 M solution
in toluene) were injected phenylsilane (0.18 g, 1.66
mmol) and ethanol (0.11 g, 2.43 mmol) in that order
at room temperature. The reaction mixture immediately
turned deep yellow with vigorous gas evolution. After
disappearance of the gas evolution the reaction mixture
was heated at 50 8C. The reaction medium became
viscous. After 48 h, the catalyst was deactivated by
exposure to the air for a minute. The mixture was passed
3.2.5. Reaction of PhSiH2ꢁ
([Si]:[EtOH]ꢀ1:2.0) catalyzed by Cp2TiCl2/Red-Al
Off-White powder, yield 70%. Mwꢀ1620, Mnꢀ670.
IR (KBr pellet): 3062, 3030, 2976, 2883, 2126, 1583,
/
SiH2Ph and EtOH
/
/
/
1
1434, 1137, 897. H-NMR (CDCl3, 300 MHz): d 1.10ꢁ
1.28 (m, br, OCH2CH3), 3.60ꢁ3.91 (m, br, OCH2CH3),
7.0ꢁ7.4 (br, Ph).
/
/
rapidly through a silica gel column (28ꢁ
/
200 mesh, 20ꢄ
/
/
2 cm) using 200 ml diethyl ether as an eluent. Removal
of the volatiles in vacuo yielded a pale yellow tacky
product. The tacky product was washed well with dry n-
3.2.6. Reaction of PhCH2SiH3 and EtOH
([Si]:[EtOH]ꢀ1:1.5) catalyzed by Cp2TiCl2/Red-Al
Off-White powder, yield 77%. Mwꢀ1010, Mnꢀ360.
IR (KBr pellet): 3063, 2924, 2889, 2157, 1593, 1496,
1060. 1H-NMR (CDCl3, 300 MHz): d 1.03ꢁ
1.15 (m, br,
OCH2CH3), 1.88ꢁ2.13 (br, PhCH2Si), 3.55ꢁ3.69 (m, br,
OCH2CH3), 7.02ꢁ
hexane (10 mlꢄ3) and dried in vacuo to give 0.21 g of
/
/
off-white brittle powder which was soluble in most
organic solvents. The combined washing solution was
evaporated at reduced pressure to yield 0.04 g of a clear
oil (PhSi(OEt)3).
/
/
/
/
/
Off-white powder, yield 76%, Mwꢀ
/
1030, Mnꢀ690.
/
/
7.28 (br, Ph).
IR (KBr pellet): 3052, 2919, 2878, 2166, 1424, 1137,
1
1050, 845, 732. H-NMR (CDCl3, 300 MHz): d 0.93ꢁ
1.19 (br, OCH2CH3), 3.54ꢁ3.83 (br, OCH2CH3), 6.80ꢁ
7.80 (br, Ph).
/
/
/
i
3.2.7. Reaction of PhSiH3 and PrOH
Clear oil, yield 10%, IR (KBr pellet): 3.67, 3.37, 2929,
2883, 1588, 1424, 1396, 1260, 1169, 958. 1H-NMR
([Si]:[iPrOH]ꢀ
Off-White powder, yield 64%. Mwꢀ
IR (KBr pellet): 3073, 3046, 2927, 2896, 2166, 1963,
/
1:1.5) catalyzed by Cp2TiCl2/Red-Al
/
750, Mnꢀ570.
/
(CDCl3, 300 MHz): d 1.14ꢁ
OCH2CH3), 3.75ꢁ3.83 (q, Jꢀ
7.21ꢁ7.41 (m, 3H, Ph), 7.57ꢁ7.63 (m, 2H, Ph). 7.57ꢁ
7.63 (m, 2H, Ph).
/
1.19 (t, Jꢀ/7.0 Hz, 3H,
1
/
/7.0 Hz, 2H, OCH2CH3),
1822, 1593, 1431, 1129, 1036. 848. H-NMR (CDCl3,
/
/
/
300 MHz): d 0.8ꢁ
/
1.27 (br, CH(CH3)2), 3.22ꢁ3.65 (br,
/
CH(CH3)2), 6.82ꢁ7.74 (br, Ph).
/

98
B.-H. Kim et al. / Journal of Organometallic Chemistry 685 (2003) 93ꢁ98
/
3.3. Synthesis of poly(alkoxysilane)s with Group VIII
metallocene catalysts
MHz): d 0.98ꢁ
PhCH2Si), 3.53ꢁ
Ph).
/
1.11 (br, OCH2CH3), 1.94ꢁ
/
2.13 (br,
7.52 (br,
/
3.71 (br, OCH2CH3), 6.75ꢁ
/
3.3.1. General procedure for the reaction of PhSiH3 and
EtOH ([Si]:[EtOH]ꢀ/1:1.5) catalyzed by Cp2Co
Off-White powder, yield 87%. Mwꢀ
IR (KBr pellet): 3061, 2976, 2926, 2851, 1894, 1721,
1595, 1435, 1390, 1296, 1134, 1070. 736. 1H-NMR
/
1470, Mnꢀ790.
/
Acknowledgements
This research was supported by the Leading Re-
searcher Research Fund, Korea Research Foundation
(Project No. 2000-041-D00165).
(CDCl3, 300 MHz): d 0.79ꢁ
3.46ꢁ3.70 (br, OCH2CH3), 7.08ꢁ
7.49 (br, Ph).
/
1.04 (br, OCH2CH3),
/
/
7.20 (br, Ph), 7.26ꢁ
/
3.3.2. Reaction of PhSiH3 and EtOH ([Si]:[EtOH]ꢀ
1:1.5) catalyzed by Cp2Ni
Off-White powder, yield 78%. Mwꢀ
IR (KBr pellet): 3078, 3047, 2975, 2929, 2176, 1962,
1
1823, 1579, 1424, 1393, 1163, 1040, 953, 735. H-NMR
/
References
/
610, Mnꢀ
/
580.
[1] J.M. Zeigler, L.A. Harrah, A.W. Johnson, Proc. SPIE-Int. Soc.
Opt. Eng. 539 (1985) 166.
[2] D. Seyferth, T.G. Wood, H.J. Tracy, J.L. Robinson, J. Am.
Chem. Soc. 75 (1992) 1300.
(CDCl3, 300 MHz): d 1.04ꢁ
/
1.18 (br, OCH2CH3), 3.10ꢁ
/
3.65 (br, OCH2CH3), 6.78ꢁ7.82 (br, Ph).
/
[3] R.G. Kepler, J.M. Zeigler, L.A. Harrah, S.R. Kurtz, Phys. Rev. B
35 (1987) 2818.
[4] F. Kajzar, J. Messier, C. Rosilio, J. Appl. Phys. 60 (1986) 3040.
[5] R.D. Miller, J. Michl, Chem. Rev. 89 (1989) 1359.
[6] R.D. Miller, R. Sooriyakumaran, Macromolecules 21 (1988)
3120.
3.3.3. Reaction of PhSiH3 and MeOH
([Si]:[MeOH]ꢀ1:1.5) catalyzed by Cp2Co
Off-White powder, yield 81%. Mwꢀ5900, Mnꢀ
/
/
/
1110.
IR (KBr pellet): 3078, 3052, 2890, 1723, 1130, 1070, 998,
738, 698. 1H-NMR (CDCl3, 300 MHz): d 3.00ꢁ
3.33 (br,
OCH3), 7.16ꢁ7.77 (br, Ph).
[7] H. Stueger, R. West, Macromolecules 21 (1985) 2349.
[8] K. Matyjaszewski, J. Inorganic. Organomet. Polym. 1 (1991) 463.
[9] T. Seki, A. Thonai, T. Tamaki, K. Ueno, J. Chem. Soc. Chem.
Commun. (1993) 1876.
/
/
[10] Y. Nakano, S. Murai, R. Kani, S. Hayase, J. Polym. Sci. Part A:
Polym. Chem. 31 (1993) 1876.
3.3.4. Reaction of PhSiH3 and PhOH ([Si]:[PhOH]ꢀ
1:1.5) catalyzed by Cp2Co
Off-White powder, yield 88%. Mwꢀ
IR (KBr pellet): 3063, 1982, 1641, 1498, 1136, 928. 698.
1H-NMR (CDCl3, 300 MHz): d 6.20ꢁ
7.80 (br, Ph).
/
[11] (a) C.T. Aitken, J.F. Harrod, E. Samuel, J. Organomet. Chem.
279 (1985) C11;
/
5260, Mnꢀ660.
/
(b) H.-G. Woo, T.D. Tilley, J. Am. Chem. Soc. 111 (1989) 8043;
(c) J.Y. Corey, X.-H. Zhu, Organoemtallics 11 (1992) 672;
(d) F. Gauvin, J.F. Harrod, H.-G. Woo, Adv. Organomet. Chem.
42 (1998) 363;
/
3.3.5. Reaction of PhSiH3 and CF3CF2CF2CH2OH
([Si]:[CF3CF2CF2CH2OH]ꢀ1:1.5) catalyzed by
Cp2Co
Off-White powder, yield 75%. Mwꢀ2100, Mnꢀ520.
IR (KBr pellet): 3078, 3011, 1957, 1824, 1593, 1434,
1
1229, 1127, 1060, 912, 732, 697. H-NMR (CDCl3, 300
(e) T.D. Tilley, Acc. Chem. Res. 26 (1993) 22.
/
[12] J.P. Banovetz, Y.-L. Hsiao, R.M. Waymouth, J. Am. Chem. Soc.
115 (1993) 2540.
[13] J.P. Banovetz, Y.-L. Hsiao, R.M. Waymouth, Polym. Prepr. 34
(1993) 228Am. Chem. Soc. Div. Polym. Chem..
/
/
[14] E. Lukevics, M. Dzintara, J. Organomet. Chem. 295 (1985) 265.
[15] C.G. Pitt, in: A.L. Rheingold (Ed.), Homoatomic Rings, Chains,
and Macromolecules of Main-Group Elements, Elsevier Scientific
Publishing Company, Amsterdam, 1977, p. 203.
MHz): d 3.41ꢁ
/
4.13 (br, CF3CF2CF2CH2OH), 6.81ꢁ
/
7.74 (br, Ph).
[16] T.C. Bedard, J.Y. Corey, J. Organomet. Chem. 428 (1992) 315.
[17] L.H. Sommer, J.E. Lyons, J. Organomet. Chem. 89 (1967) 1521.
[18] L.H. Sommer, J.D. Citron, J. Org. Chem. 32 (1967) 2470.
[19] R.J.P. Corriu, J.J. Moreau, J. Chem. Soc. Chem. Commun.
(1973) 38.
3.3.6. Reaction of PhSiH2SiH2Ph and EtOH
([Si]:[EtOH]ꢀ1:2) catalyzed by Cp2Co
Off-White powder, yield 92%. Mwꢀ3910, Mnꢀ
/
/
/
2190.
[20] (a) R.J.P. Corriu, J.J. Moreau, Tetrahedron Lett. (1973) 4469;
(b) R.J.P. Corriu, J.J. Moreau, J. Org. Chem. 114 (1976) 135;
(c) R.J.P. Corriu, J.J. Moreau, J. Org. Chem. 127 (1977) 7;
(d) R.J.P. Corriu, J.J. Moreau, J. Org. Chem. 120 (1976) 337.
[21] I. Ojima, T. Kogure, M. Nihonyanagi, H. Kono, S. Inaba, Y.
Nagai, Chem. Lett. (1973) 501.
IR (KBr pellet): 3070, 3042, 2920, 2887, 1957, 1824,
1
1596, 1423, 1390, 1134, 1056, 956, 789, 733. H-NMR
(CDCl3, 300 MHz): d 0.60ꢁ
/
1.20 (br, OCH2CH3), 3.21ꢁ
/
3.84 (br, OCH2CH3), 7.62ꢁ7.82 (br, Ph).
/
[22] (a) L.H. Sommer, J.E. Lyons, J. Am. Chem. Soc. 89 (1967) 1521;
(b) L.H. Sommer, J.E. Lyons, J. Am. Chem. Soc. 91 (1967) 761.
[23] J.Y. Corey, Adv. Silicon Chem. 1 (1991) 327.
[24] B.-H. Kim, H.-G. Woo, in preparation.
3.3.7. Reaction of PhCH2SiH3 and EtOH
([Si]:[EtOH]ꢀ1:1.5) catalyzed by Cp2Co
Off-White powder, yield 64%. Mwꢀ3320, Mnꢀ
/
/
/
1970.
IR (KBr pellet): 30762, 2925, 1870, 1736, 1601, 1493,
1392, 1293, 1175, 1073, 959, 696. 1H-NMR (CDCl3, 300
[25] W.L.F. Armarego, D.D. Perrin, Purification of Laboratory
Chemicals, fourth ed., Butterworth Heinemann, Oxford, 1996.