AlCl3-catalyzed hydrosilylation of alkynes with hydropolysilanes

Article abstract of DOI:10.1021/om100376d

AlCl₃ catalyzes addition reactions of hydrooligosilanes (H(SiMe₂)_nR; n = 2-4, R = H, Me, Ph) with 1-decyne and other alkynes under mild conditions. In most reactions the Si-Si bonds remain intact to form anticipated products in fair to excellent yields, although Si-Ph bonds appear to be cleaved partially under the conditions. Arylethynes tend to form abnormal products due to Si-Si bond scission, but at a low temperature, the addition reaction proceeds normally. The reaction of 1,2- dihydrotetramethyldisilane with 1-decyne furnishes 1,2-didecenyldisilane, 1,3-didecenyltrisilane, and other byproducts at 0 °C, while the reaction run at a lower temperature proceeds cleanly. 1,3-Dihydrohexamethyltrisilane reacts more cleanly even at 0 °C. The reaction of pentamethyldisilane with 1,6-heptadiyne proceeds in a different direction, leading to cyclization. 1,7-Octadiyne reacts with 1,3-dihydrohexamethyltrisilane to give a polymeric material. The reaction of 1,2,3-trihydropentamethyltrisilane or poly(phenylsilylene) with 1-dectyne proceeds cleanly without perceptible Si-Si bond cleavage.

Full text of DOI:10.1021/om100376d

5274 Organometallics 2010, 29, 5274–5282
DOI: 10.1021/om100376d
AlCl3-Catalyzed Hydrosilylation of Alkynes with Hydropolysilanes†
Nobu Kato, Yusuke Tamura, Taigo Kashiwabara, Takanobu Sanji, and Masato Tanaka*
Chemical Resources Laboratory, Tokyo Institute of Technology, Nagatsuta,
Midori-ku,Yokohama 226-8503, Japan
Received April 30, 2010
AlCl3 catalyzes addition reactions of hydrooligosilanes (H(SiMe2)nR; n = 2-4, R = H, Me, Ph) with
1-decyne and other alkynes under mild conditions. In most reactions the Si-Si bonds remain intact to form
anticipated products in fair to excellent yields, although Si-Ph bonds appear to be cleaved partially under
the conditions. Arylethynes tend to form abnormal products due to Si-Si bond scission, but at a low
temperature, the addition reaction proceeds normally. The reaction of 1,2-dihydrotetramethyldisilane with
1-decyne furnishes 1,2-didecenyldisilane, 1,3-didecenyltrisilane, and other byproducts at 0 °C, while the
reaction run at a lower temperature proceeds cleanly. 1,3-Dihydrohexamethyltrisilane reacts more cleanly
even at 0 °C. The reaction of pentamethyldisilane with 1,6-heptadiyne proceeds in a different direction,
leading to cyclization. 1,7-Octadiyne reacts with 1,3-dihydrohexamethyltrisilane to give a polymeric
material. The reaction of 1,2,3-trihydropentamethyltrisilane or poly(phenylsilylene) with 1-dectyne
proceeds cleanly without perceptible Si-Si bond cleavage.
Introduction
H(SiMe2)nR, has been believed to be a rather tough and intri-
cate task due to the Si-Si bond cleavage,2 although very few
successful examples have been encountered incidentally.3 For
instance, Urenovitch and West reported long ago that attempted
platinum-catalyzed reaction of 1-octene with pentamethyldi-
silane gave trimethylsilane and a trace of octyltrimethylsilane.4
Besides transition metal complexes, Lewis acids are also
known to catalyze the hydrosilylation with hydromonosilanes.5
Rosenberg and co-workers have reported Lewis acid-catalyzed
reactions of thiobenzophenone, thiols, phenols, thiophenols,
aldehydes, and R-diketones with hydrodisilanes.6 However,
Lewis acid-catalyzed reactions of hydrooligo- and hydro-
polysilanes with unsaturated carbon linkages have not been
documented.7 This article discloses that AlCl3 is a capable
catalyst to promote the addition of hydrooligosilanes and
hydropolysilanes to alkynes without deterioration of the silicon
chain under carefully tuned conditions. A possible side reac-
tion, which we have to keep in mind beforehand, is skeletal
rearrangement of Si-Si chains.8 In the present study, such a
Hydrosilylation is a long-known reaction and is an indispen-
sable tool to create a silicon-to-carbon bond.1 The majority
of precedents deal with reactions with hydromonosilanes such
as trichlorosilane, phenyldimethylsilane, trimethoxysilane, and
diphenylsilane. As far as transition metal-catalyzed hydro-
silylation is concerned, the reaction with a hydrooligosilane,
† Part of the Dietmar Seyferth Festschrift.
*To whom correspondence should be addressed. E-mail: m.tanaka@
res.titech.ac.jp.
(1) Reviews: (a) Comprehensive Handbook on Hydrosilylation; Marciniec,
B., Ed.; Pergamon Press: Oxford, 1992. (b) Ojima, I.; Li, Z.; Zhu, J. In The
Chemistry of Organic Silicon Compounds; Rappoport, Z., Apeloig, Y., Eds.;
John Wiley & Sons: New York, 1998; Vol. 2, Pt. 2, pp 1687-1792. (c) Hydro-
silylation; Marciniec, B., Ed.; Advances in Silicon Science 1; Springer: Berlin,
2009.
(2) (a) Sharma, H. K.; Pannell, K. H. Chem. Rev. 1995, 95, 1351. (b)
Radical hydrosilylation of alkynes with hydrodisilanes was reported to
proceed without deterioration of the Si-Si chain. See: Miura, K.; Oshima,
K.; Utimoto, K. Bull. Chem. Soc. Jpn. 1993, 66, 2356.
(3) (a) Yamamoto, K.; Kumada, M.; Nakajima, I.; Maeda, K.;
Imaki, N. J. Organomet. Chem. 1968, 13, 329. (b) Tamao, K.; Asahara,
M.; Kawachi, A. J. Organomet. Chem. 1996, 521, 325.
(6) (a) Harrison, D. J.; McDonald, R.; Rosenberg, L. Organometallics
2005, 24, 1398. (b) Harrison, D. J.; Edwards, D. R.; McDonald, R.; Rosenberg, L.
Dalton Trans. 2008, 3401. (c) Skjel, M. K.; Houghton, A. Y.; Kirby, A. E.;
Harrison, D. J.; McDonald, R.; Rosenberg, L. Org. Lett. 2010, 12, 376.
(7) Lewis acid-mediated functionalization of surface Si-H bonds of
porous silicon and related materials with alkenes or alkynes has been
documented. The integrity of the local structure where the reaction took
place is uncertain. (a) Buriak, J. M.; Allen, M. J. J. Am. Chem. Soc. 1998,
120, 1339. (b) Holland, J. M.; Stewart, M. P.; Allen, M. J.; Buriak, J. M. J. Solid
State Chem. 1999, 147, 251. (c) Nelles, J.; Sendor, D.; Ebbers, A.; Petrat, F. M.;
Wiggers, H.; Schulz, C.; Simon, U. Colloid Polym. Sci. 2007, 285, 729.
(8) (a) Ishikawa, M.; Kumada, M. J. Chem. Soc. D, Chem. Commun.
1970, 157. (b) Ishikawa, M.; Iyoda, J.; Ikeda, H.; Kotake, K.; Hashimoto, T.;
Kumada, M. J. Am. Chem. Soc. 1981, 103, 4845. (c) Ishikawa, M.;
Watanabe, M.; Iyoda, J.; Ikeda, H.; Kumada, M. Organometallics 1982, 1,
317. (d) Blinka, T. A.; West, R. Organometallics 1986, 5, 128. (e) Fischer, J.;
Baumgartner, J.; Marschner, C. Science 2005, 310, 825. (f) Wagner, H.;
Wallner, A.; Fischer, J.; Flock, M.; Baumgartner, J.; Marschner, C. Organo-
metallics 2007, 26, 6704. See also: (g) Wagner, H.; Baumgartner, J.; M€uller,
T.; Marschner, C. J. Am. Chem. Soc. 2009, 131, 5022.
(4) Urenovitch, J. V.; West, R. J. Organomet. Chem. 1965, 3, 138.
(5) (a) Review: Jung, I. N.; Yoo, B. R. Adv. Organomet. Chem. 2005, 53,
41. (b) Finke, U.; Moretto, H. (to Bayer A.-G.) DE 1979-2804204A1; Chem.
Abstr. 1979, 91, 193413x. (c) Oertle, K.; Wetter, H. Tetrahedron Lett. 1985,
26, 5511. (d) Anwar, S.; Davis, A. P. Tetrahedron 1988, 44, 3761. (e) Yamamoto,
K.; Takemae, M. Synlett 1990, 259. (f) Sudo, T.; Asao, N.; Gevorgyan, V.;
Yamamoto, Y. J. Org. Chem. 1999, 64, 2494. (g) Rubin, M.; Schwier, T.;
Gevorgyan, V. J. Org. Chem. 2002, 67, 1936. (h) Song, Y.-S.; Yoo, B. R.; Lee,
G.-H.; Jung., I. N. Organometallics 1999, 18, 3109. (i) Asao, N.; Yamamoto, Y.
Bull. Chem. Soc. Jpn. 2000, 73, 1071. (j) Parks, D. J.; Blackwell, J. M.; Piers,
W. E. J. Org. Chem. 2000, 65, 3090. (k) Dias, E. L.; Brookhart, M.; White, P. S.
Chem. Commun. 2001, 423. (l) Asao, N.; Ohishi, T.; Sato, K.; Yamamoto, Y.
Tetrahedron 2002, 58, 8195. (m) Roesler, R.; Har, B. J. N.; Piers, W. E.
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r
pubs.acs.org/Organometallics
Published on Web 06/24/2010
2010 American Chemical Society

Article
Organometallics, Vol. 29, No. 21, 2010 5275
Table 1. Reactions of Alkynes with Pentamethyldisilane 1aa
conversionb
R1CtCR2 2
temp (°C),
time (h)
product; % GC yieldb
(isolated yield)
entry
R1 =, R2 =
1
2
1
2
2A, n-Bu, n-Bu
2B, Ph, Ph
2C, n-Oct, H
2C
2D, Ph, H
2D
2D
0, 1
0, 1
0, 1
0, 1
100
100
100
91
100
100
94
100
91
100
69
100
85
100
99
100
100
100
90
(Z)-3aA; 94 (80), (E)-3aA; 5
(Z)-3aB; 80 (62)
(Z)-3aC; 71 (44), r-3aC; 2
(Z)-3aC; 77
(Z)-3aD; 36 (29), 4; 13
(Z)-3aD 46, 4; 26
(Z)-3aD; 68, 4; 10
(Z)-3aD; 28, 4; 37 (31)
(Z)-3aD; 70 (54), 4; 7
(Z)-3aE; 48f (43), r-3aE; 3f
(Z)-3aF; 8, (E)-3aF; 7
3-1
3-2c
4-1
4-2
4-3
4-4d
4-5e
5
0, 1
-14, 1
-42, 2
-42, 5
-42, 2
0, 1
2D
2D
99
100
49
2E, Cl(CH2)3, H
2F, p-An, H
6
0, 24
a Reaction conditions: 1a (1.0 mmol), 2 (1.0 mmol), AlCl3 (10 mol %), CH2Cl2 1 mL, in a 25 mL reactor. b Determined by GC using n-dodecane as an
internal standard. The figures in parentheses are isolated yields. c Run in toluene. d Run in 10 mL of CH2Cl2. e Run in 0.5 mL of CH2Cl2. f Determined by
GC using n-octane as an internal standard.
Scheme 1
Scheme 2
of the mixture showed two other products were also formed.
One of these, formed in 2% yield, was a branched one, 2-penta-
methyldisilanyl-1-decene, r-3aC, the structure of which was
confirmed by comparison with an authentic sample prepared
via a separate route. The other, which was formed in <1%
yield, appeared to be (E)-3aC on the basis of comparison of its
MS data with those of (Z)-3aC.9 The reaction of phenyla-
cetylene 2D afforded (Z)-3aD (Scheme 2). However its GC yield
was only 36%. Since the conversions of the disilane and phenyl-
acetylene were both near 100%, the material balance of this
particular reaction was obviously unsatisfactory. Search for
other byproducts showed that compound 4 was a major
byproduct (13% GC yield). To suppress its formation (vs the
formation of (Z)-3aD), a much lower reaction temperature
(-42 °C, entry 4-3) and a minimized quantity of the solvent
(entry 4-5) were favorable. On the other hand, a reaction run in a
more diluted solution (entry 4-4) formed 4 more extensively
(relative to the formation of (Z)-3aD) and enabled us to
successfully isolate 4, allowing full characterization and mecha-
nistic discussion (vide infra).
As was anticipated, alkynes bearing functional groups
were reluctant to cleanly or smoothly react. The reaction of
5-chloro-1-pentyne (2E) afforded a complex mixture of
products, among which anticipated product (Z)-3aE was
found in 48% GC yield, along with a small quantity of
r-3aE. The reaction of p-anisylacetylene 2F was quite slow
as compared with parent phenylacetylene, and a complex
mixture resulted to afford an approximately 1:1 mixture of
(Z)- and (E)-3aF in 15% total yield.10 Other alkynes such as
side reaction did proceed depending on the substrate, but could
be readily minimized by tuning the conditions.
Results and Discussion
Before commencement of the present study, we briefly
examined the reaction of 1-decyne with triethylsilane according
to the reported procedure.5f The results were not always consis-
tent, which appeared to be associated with the purification
procedure of AlCl3. After various attempts, we have come to a
best method, which furnishes reproducible results not only in
the foregoing reaction with triethylsilane but also in the reac-
tions with hydrooligosilanes. We strongly advise to strictly
adhere to the procedure given in the Experimental Section,
somewhat detailed in Figure S1 in the Supporting Information.
Reaction of Pentamethyldisilane with Alkynes. A trial
reaction of pentamethyldisilane 1a with 5-decyne 2A was
run under the standard conditions using AlCl3 (10 mol %) in
dichloromethane at 0 °C for 1 h. The resulting mixture was
analyzed by GC to reveal (Z)-5-pentamethyldisilanyl-5-
decene, (Z)-3aA, being formed in 94% yield. GC and GC-MS
analyses suggested that an isomer, presumably (E)-3aA, was
also formed in 5% yield. Evaporation afforded a nearly pure
sample, which was further purified by column chromatography
to furnish (Z)-3aA as a colorless oil in 80% yield.
Similar reactions of other acetylenes are summarized in
Table 1.
Diphenylacetylene 2B also reacted fairly well to form
(Z)-3aB in 80% GC (62% isolated) yield. Unlike the reaction
of 5-decyne, the E-isomer was not detected in the reaction
mixture.
The reactions of terminal acetylenes, on the other hand, were
somewhat complex. Thus, 1-decyne 2C formed (Z)-1-penta-
methyldisilanyl-1-decene, (Z)-3aC, in 71% GC yield. GC analysis
(9) GC analysis showed that traces of many other products were also
formed. GC-MS suggested that one of them was a compound coming
from one molecule of 1-decyne and two molecules of pentamethyldisi-
lane. Although detailed structural characterization was not made, it can
be a simple double addition product or a compound like 4 found in the
phenylacetylene reaction (vide infra).
(10) (2-p-Anisylethyl)pentamethyldisilane was also formed in ap-
proximately 1% yield.

5276 Organometallics, Vol. 29, No. 21, 2010
Kato et al.
Scheme 3
Figure 1. Molecular structure of 40. Thermal ellipsoids are
shown at the 50% probability level. Hydrogen atoms except
H1 are omitted for clarity.
Chart 1
3-methoxy-1-propyne, methyl 5-hexynoate,11 5-hexynenitrile,
and 6-methoxyl-1-hexyne did not react at all under the
standard conditions.
Scheme 4
The structure of 4 was characterized by NMR and MS
study. To gain more convincing evidence, however, we ran a
reaction of p-tert-butylphenylacetylene (2D0) with 2 equiv of
1a at -15 °C for 5 h. The reaction afforded 40 (40% isolated
yield), along with a simple addition product, (Z)-3aD0, and
two isomeric products, 5 and 6 (Chart 1), coming from
double addition of 1a to 2D0 in ∼2, 6.3, and 4.4% yields,
respectively. Compound 40 displayed NMR spectroscopic
features very similar to 4. Further purification by careful
recrystallizations, first from hexane and then from methanol,
afforded a prism. Its X-ray diffraction study confirmed the
structure unequivocally as shown in Figure 1.
The structures of 4 and 40 indicate that two molecules of
the disilane reacted, involving Si-Si bond scission. What we
presume has taken place is outlined in Scheme 3. A key
feature lies in that the bond scission takes place before a
second molecule of 1a reacts, presumably via intermediates I,
II, and III (IV) (vide infra).
To gain supportive observations relevant to the mechanistic
detail, several experiments were carried out (Scheme 4). First, an
authentic sample of (Z)-3aD, prepared beforehand, was treated
with 1a at 0 °C using 10 mol % AlCl3. The reaction was unex-
pectedly slow as compared with entries 4-1-4-5, which started
with 1a and 2D and were envisioned to proceed via (Z)-3aD; the
yield of 4 was 60% even after 42.5 h at 0 °C. This indicates that
rearrangement of authentic (Z)-3aD used as starting material is
slow as compared with the rearrangement of the intermediary
(Z)-3aD generated incidentally in the reaction of 1a and 2D that
proceeds even at -42 °C. A second observation relevant to the
mechanism is an attempted rearrangement of (Z)-3aD in the
absence of 1a run at -14 °C, which resulted in nearly complete
recovery of (Z)-3aD even though the rearrangement leading to 4
did proceed during the reaction of 2D with 1a at the same
temperature and also at -42 °C (entries 4-1-4-5). Finally, the
reaction of (Z)-1-phenyl-1-propene, somewhat similar to (Z)-2-
pentamethyldisilanylstyrene in that these are both β-substituted
styrenes, proceeded normally without rearrangement to afford
1-phenyl-2-pentamethyldisilanylpropane, 7. The disilanyl group
is attached to the β-carbon (central carbon in the propane chain)
in product 7,12 while it is bound to the R-carbon (benzylic
carbon) in 4 and 40.
(11) Despite the lack of reactivity of methyl 5-hexynoate in our
attempt, Lewis acid-catalyzed hydrosilylation of propiolate esters with
HSi(SiMe3)3 has been reported. See ref 5n.
(12) Details will be reported separately.

Article
Organometallics, Vol. 29, No. 21, 2010 5277
Scheme 5
Scheme 6
Chart 2
The foregoing observations and the concentration-dependent
ratio of (Z)-3aD:4 in the catalytic reaction (entries 4-3-4-5)
appear to substantiate the formation of 4 as illustrated in
Scheme 3. We presume that the skeletal rearrangement leading
eventually to 4 proceeds before a second molecule of 1a reacts
with intermediary (Z)-3aD, but does not proceed so easily once
(Z)-3aD has left the proximity of AlCl3. In the reaction starting
with 2D with 1a, the disilanyl linkage in (Z)-3aD is envisioned to
rearrange via intermediates I-III (IV). In the reaction run in a
dilute solution (entry 4-4), rearrangement, which is a unimole-
cular process, should be favored (in terms of selectivity relative
to (Z)-3aD) and proceeds rather easily even at a lower tempera-
ture, leading eventually to 4. In a more concentrated solution
(entry 4-5), on the other hand, another molecule of 1a may
interact with intermediate I to liberate (Z)-3aD, which is
reluctant to re-enter the catalytic cycle for the rearrangement.
The AlCl3-catalyzed skeletal rearrangement of linear peralkyl
polysilanes usually requires heating,6b which agrees with the
lack of rearrangement in 1-phenyl-2-pentamethydisilanylpro-
pane (7) formed in the reaction of (Z)-1-phenyl-1-propene. This
observation also indicates that the rearrangement forming 4and
40 is not an event that proceeds after addition of 1a has formed
saturated adducts such as 5 and 6.
Reaction of Other Hydrooligosilanes with Alkynes. Under
the standard conditions, the reaction of 1-decyne (2C) with
1,1,2,2-tetramethyl-2-phenyldisilane (1b) proceeded smoothly
to form (Z)-1-(2-phenyl-1,1,2,2-tetramethydisilanyl)-1-decene,
(Z)-3bC, in 64% GC (46% isolated) yield (Scheme 5). However
the conversions of 1b and 2C were both >98%, indicating
unsatisfactory material balance. GC analysis showed traces of
many unidentified byproducts being formed. We presume that
these byproducts, at least in part, have come from the aryl-Si
bond cleavage, which has been known to take place incidentally
in AlCl3-catalyzed hydrosilylation.5f,h,13
was (Z)-3dC, suggesting that rearrangement involving Si-Si
bond scission had taken place to a minute extent.
Reaction of r,ω-Dihydrooligosilanes. Unlike 1-hydrooligo-
silanes, R,ω-dihydrooligosilanes are tricky reagents to con-
trol the reactivity. When 1,2-dihydrotetramethyldisilane
(1e) was allowed to react with 1-decyne (2C) (2.0 equiv)
at 0 °C using AlCl3 (10 mol % relative to Si-H bond), the
reaction proceeded somewhat slowly as compared with that
with pentamethyldisilane. GC analysis after 4 h revealed
1,2-di[(Z)-1-decen-1-yl]tetramethyldisilane, (Z,Z)-8eC, being
formed in only 11% GC yield (Scheme 6). Quite surprisingly,
however, 1,3-di[(Z)-1-decen-1-yl]hexamethyltrisilane, (Z,Z)-
8fC, was also found to be formed in 12% GC yield. Besides
these, GC and GC-MS analyses suggested the formation of
other isomers of (Z,Z)-8eC and (Z,Z)-8fC, which were not
isolated and thus were not fully characterized. However, we
presume, in view of the formation of r-3aC in the reaction of
2C with 1a, that a major byproduct that displayed a peak
(∼7% yield) just before (Z,Z)-8eC in the gas chromatogram
would be the (Z),R-isomer of (Z,Z)-8eC (Chart 2). Other
1
support for this isomer came from H NMR analysis of the
crude mixture. Thus, the crude mixture obtained after routine
workup, displayed, besides the main signals due to (Z,Z)-8eC,
weak signals at 5.34-5.37 (m) and 5.75-5.78 (m), which
agreed fairly well with the values for an authentic sample of
r-3aC.14 GC-MS analysis also supported the structure (m/z
394 corresponding to [M]þ).15 As was the case for 1-hydro-
oligosilanes, 1e reacted more cleanly at a lower temperature
(-42 °C) to give (Z,Z)-8eC in 82% GC (71% isolated) yield,
and (Z,Z)-8fC was not formed in an appreciable quantity at
this temperature, although traces of (Z),R- and R,R-isomers
appeared to be formed.
The reaction of 1,3-dihydrohexamethyltrisilane (1f) with
2C was somewhat slow (0 °C, 8 h) as compared with that of
1e and also formed both (Z,Z)-8eC and (Z,Z)-8fC in 3% and
70% GC yields (Scheme 7). GC analysis showed that isomers
of (Z,Z)-8fC were also formed (approximately 20%), indi-
cating that the reaction resembles the foregoing reaction of
Longer chained hydrooligosilanes react more neatly than
shorter ones. Thus, similar reactions of 1-hydroheptamethyltri-
silane (1c) and 1-hydrononamethyltetrasilane (1d) with 1-de-
cyne (2C) afforded (Z)-1-heptamethyltrisilanyl-1-decene, (Z)-
3cC, and (Z)-1-nonamethyltetrasilanyl-1-decene, (Z)-3dC, in
88% (64% isolated) and 86% (75% isolated) GC yields, respec-
tively. The reactions were clean, and only traces of byproducts
were observed. In the former reaction, one of the byproducts
(13) See also for well-established electrophile-induced desilylation at
the aryl-Si bond, often catalyzed by AlCl3: (a) Bassindale, A. R.;
Taylor, P. G. In The Chemistry of Organic Silicon Compounds; Patai, S.,
Rappoport, Z., Eds.; Wiley: Chichester, U.K., 1989; Part 2, pp 909-919. (b)
Colvin, E. W. Arylsilanes. Silicon in Organic Synthesis; Butterworths:
London, 1981; pp 125-133.
(14) The SiEt3 analogue of r-3aC displays corresponding 1H NMR
signals at 5.28 (m) and 5.63 ppm. See: Takeuchi, R.; Tanouchi, N.
J. Chem. Soc., Perkin Trans. 1 1994, 2909.
(15) (Z),R- and R,R-isomers corresponding to (Z,Z)-8fC could have
also been formed as byproduct, although we did not try to search for
these.

5278 Organometallics, Vol. 29, No. 21, 2010
Kato et al.
Scheme 7
Scheme 10
Scheme 8
electron-rich, may have induced higher reactivity of the
aryl-Si bond toward protiodesilylation.17
Cyclization Reaction. Cyclization of 1,6-heptadiyne (2H)
with 1a (4 equiv) proceeded at -10 °C to give product 9 in 76%
GC (65% isolated) yield (Scheme 9). In another reaction run at
0 °C using 1 equiv of 1a, the yield decreased to 36% GC yield.18
An NOE experiment with product 9, which displayed a 6%
enhancement of the alkenyl proton at 6.09 ppm upon irradia-
tion of the terminal methylene proton at 5.27 ppm, confirmed
the stereochemistry. The structure is basically the same as the
product obtained from 2H and hydromonosilanes.5f,j Ni-
catalyzed reactions of 1,7-octadiyne with hydromono-
silanes are known to afford cyclized products, albeit in a
different direction. However, the catalyst system is unable
to cyclize 1,6-heptadiyne with hydrosilanes.19
Scheme 9
Extension to Polymer Synthesis. The foregoing procedures
can be successfully extended to polymer synthesis. When 1,7-
octadiyne (2J) was treated with 1,3-dihydrohexamethyltri-
silane (1f) (0.5 equiv) in the presence of AlCl3 (10 mol %
relative to 2J) in CH2Cl2 at 0 °C for 65 h, cyclization did not
appear to have proceeded, but a mixture of oligomeric and
polymeric materials (poly-10fJ) was formed in a nearly quanti-
tative yield (Scheme 10). GC analyses showed traces of two
oligomeric products, one comprising 1f and 2J in a 1:1 ratio
(GC-MSm/z282) and the other in a 2:1 ratio (GC-MS m/z458).
Routine workup followed by reprecipitation by addition of
methanol to a dichloromethane solution afforded oil (0.20 g)
and solid (0.08 g) fractions, which were separated by centri-
fugation. GPC analysis of the solid revealed Mn=3.3 ꢀ 103 and
Mw=2.1 ꢀ 104 (Mw/Mn=6.3). The 1H NMR spectrum of the
solid fraction displayed two olefinic protons, at 5.47 (d) and 6.32
(dt), and CH2 protons ranging from 1.26 to 2.07 in addition to
SiMe signals, supporting the structure of poly-10fJ.20 Besides
these, a septet at 3.7 was seen while no singlet signal was ob-
served evidently around 1.8 ppm, indicating that the structure of
termini was Si-H, but not CtCH. UV analysis displayed λmax
at 236 nm, reasonable for the σ,π-conjugated Si3 structure.21
The liquid fraction appeared to be a mixture of oligomeric and
polymeric materials, but was too complex to characterize.
1e, although the redistribution reaction resulting in the
change in the number of silicon atoms in the product to
form (Z,Z)-8eC was much less extensive.16
The reaction of p-di(1,1,2,2-tetramethyldisilanyl)benzene
(1g) with 1-hexyne (2G) (0 °C) was slow and resulted in a
complex mixture (Scheme 8). We were unable to conclude
that the expected product was formed, although we found
byproducts, which appeared, on the basis of GC-MS anal-
ysis, to be 1b, 1bG, and 1bG-(SiMe2)2H, in appreciable
yields. As compared with the reaction starting with 1,1,2,2-
tetramethyl-2-phenyldisilane (1b), aryl-Si bond cleavage
(vide supra) took place more extensively and caused the
complexity of the reaction with 1g. The presence of two
disilanyl groups in 1g, which makes the aromatic ring more
(16) We have encountered similar observations in transition metal-
catalyzed reactions of R,ω-dihydrooligosilanes. Among R,ω-dihydroo-
ligosilanes, 1,2-dihydrodisilanes undergo more extensive redistribution
than longer chained congeners. Details will be reported separately.
(17) Colvin, E. W. Silicon in Organic Synthesis; Butterworths: London,
UK, 1981; Chapter 10.
(18) Attempted cyclization of 1,5-hexadiyne (2I) with 1a (1 equiv
relative to 2I) failed (0 °C, 24 h, in CH2Cl2, 10 mol % AlCl3). GC and
GC-MS analyses suggested that only the adduct coming from simple
addition at the two triple bonds appeared to be formed rather selectively.
However, attempted purification of the crude mixture by distillation or
column chromatography after routine workup afforded unidentified
compounds, which hampered further characterization of the major
product. Another reaction using 2 equiv of 1a also formed the same
compound as the major product.
(19) (a) Tamao, K.; Kobayashi, K.; Ito, Y. J. Am. Chem. Soc. 1989,
111, 6478. (b) Tamao, K.; Kobayashi, K.; Ito, Y. Synlett 1992, 539.
(20) The intensity ratio of the olefinic and SiMe protons was approxi-
mately 3.6:18, indicating a deficiency of the olefinic proton for the
structure of poly-10fJ. This may suggest that the material has a
structural defect, which may have come from side reactions of an
intermediary Si-CHdCH unit with Si-H, which could lead to cross-
linking. However the 1H NMR spectrum does not permit us to propose
detailed structures.
(21) The λmax values for CH2dCH(SiMe2)3Me and Ph(SiMe2)3Ph
reported are 237 and 243 nm, respectively, while those for H(SiMe2)3H
and Me(SiMe2)3Me are 218 and 215 nm, respectively. See: Kumada, M.;
Tamao, K. Adv. Organomet. Chem. 1968, 6, 19.

Article
Organometallics, Vol. 29, No. 21, 2010 5279
Scheme 11a
Scheme 12
Finally we ran a reaction of poly(phenylsilylene) (1i) (Mw=
2.70ꢀ103, Mw/Mn=1.63 as analyzed by GPC with polysty-
rene standards) with 1-decyne (2C) (1 equiv relative to a SiHPh
repeat unit in the polymer) at 0 °C in CH2Cl2 using AlCl3
(10 mol % relative to 1-decyne) for 26 h (Scheme 12). Routine
workup gave product polymer 12 as a pale yellow oil. GPC
analysis revealed Mw=4.26ꢀ103, Mw/Mn=1.74, suggesting
that the polymer chain was modified by the reaction with
1-decyne. Although molecular weight estimation by GPC using
polystyrene standards is not very reliable, the GCP analysis
supports that chain scission has not taken place extensively.
a Determined by GC using n-octane as an internal standard. bThe
figures in parentheses are isolated yields. Based on 1h. Isolated by
c
d
e
GPC. Determined by GC using sym-tetrachroloethane as an internal
standard.
Chart 3. Possible Structures of 11-IV
1
The degree of modification was analyzed by H NMR spec-
troscopy23 only for higher molecular weight fraction 120 (sticky
oil, Mw=4.57ꢀ103, Mw/Mn=1.51), isolated by preparative
GPC. Although the signals were all broad, estimation was
made by comparison of signal intensities for Ph (6.0-8.1 ppm)
and octyl chain (0.2-2.9 ppm) regions, which suggested that
the degree of modification was 89%.
The reaction of poly(hydrosilylene)s is another approach to
polymer synthesis. A trial reaction to look into the possibility
was run using 1,2,3-trihydropentamethyltrisilane (1h) and
1-decyne (2C) (3 equiv) at 0 °C in the presence of AlCl3 (10
mol % relative to the trisilane). The reaction proceeded slowly.
Analysis after 48 h by GC using n-octane as an internal
standard revealed both starting materials remaining and for-
mation of 11-I-11-III in a total of 68% (Scheme 11). On the
basis of 1H NMR spectroscopy, material 11-II isolated appears
to be an approximately 1:1 mixture of 11-II-a and 11-II-b.
When the quantity of the catalyst was increased to 30 mol %
(i.e., 10 mol % relative to each Si-H), the reaction proceeded
faster and was complete in 3 h to give 11-III in 48% GC yield.
Byproducts of shorter retention times were not observed. How-
ever, GPC analysis suggested formation of a higher molecular
weight material, which was isolated by preparative GPC to give
93.2 mg of the higher molecular weight material 11-IV. Its 1H
NMR spectrum displayed signals arising from SiMe (0.00-
0.30 ppm) and olefinic CH (5.5 and 6.3 ppm) approximately in a
18.3:2.2 ratio, indicating that each trisilane linkage has approxi-
mately one decenyl group, which matches the structures ex-
emplified in Chart 3. Thus, olefinic bonds generated in hydro-
silylation of decyne 2C with 1h reacted further with remaining
Si-H bonds in intermediates 11-I and 11-II. However, a more
detailed structure of the polymer is uncertain at this stage.22
Conclusion
This report demonstrates clearly that AlCl3 is a capable
catalyst to promote hydrosilylation of alkynes, both terminal
and internal, with hydrooligosilanes H(SiMe2)nR (n=2-4,
R=H, Me, Ph) under mild conditions. Side reactions such as
Si-Si bond cleavage and rearrangement proceed occasion-
ally, but can be suppressed by tuning the reaction conditions.
The reaction of H(SiMe2)2H with 1-decyne (at 0 °C) gave not
only the Z,Z-adduct coming from the reaction at both
termini of H(SiMe2)2H but also the corresponding trisilane
adduct, but the latter is able to be minimized at -42 °C.
H(SiMe2)3H reacts more cleanly even at 0 °C. Cyclization of
1,6-heptadiyne with H(SiMe2)2Me also proceeds cleanly to
form a cyclohexene derivative. These hydrosilylation reac-
tions are applicable to polymerization and modification
of polysilanes such as H(SiMe2)SiMeH(SiMe2)2H and
-(SiHPh)n-. We believe these results have furnished a
somewhat detailed sketch of the landscape in the AlCl3-
catalyzed hydrosilylation to start with in future applications.
Experimental Section
Purification of AlCl3. In order to secure the reproducibility of
the AlCl3-catalyzed hydrosilylation, purification of AlCl3 should
(22) The ratio of signal intensity of the methyl region of the octyl
groups (0.86-0.9 ppm) and the olefinic C-H signals was 12.9:2.2, which
did not match the structure illustrated in Chart 3. This may be due partly
to overlapping of other signals arising from linkages such as RCHSi and
RCH2Si. However we are unable to exclude the possibility that the
material was contaminated with other octyl-rich polymeric materials.
(23) Since silicon-containing polymers occasionally fail to give satis-
factory elemental analysis due to difficulty of combustion, an estimate of
the degree of modification by elemental analysis may be less reliable than
that by 1H NMR spectroscopy.

5280 Organometallics, Vol. 29, No. 21, 2010
Kato et al.
adhere strictly to the following procedure. Under a dry nitrogen
atmosphere, AlCl3 was placed into a sublimation apparatus (glass
tube or flask fitted with a coldfinger), and the apparatus was
dipped into a hot oil bath set beforehand at 200 °C. After 1 h, the
apparatus was transferred to a glovebox, and the white sublimate
that condensed onto the coldfinger was collected and transferred to
a Schlenk tube, which was stored in the glovebox. In each reaction,
AlCl3 was weighed in the glovebox and placed into a reaction vessel
(Schlenk tube). Somewhat detailed information of the apparatus is
given as Figure S1 in the Supporting Information.
δ -2.15, -1.83, 127.28, 127.93, 128.09, 131.74, 140.03, 146.17.
29Si NMR (CDCl3): δ -27.89, -18.40. IR (neat, cm-1): 2952,
1594, 731, 694. GC-MS m/z (% relative intensity): 234 ([M]þ,
24), 161 ([M - SiMe3]þ, 100), 145 ([M - SiMe3 - Me - 1]þ, 74),
135 (26), 73 (25), 59 (5). HRMS (EI): calcd for C13H22Si2 m/z
234.1260, found 234.1256.
1-Phenyl-1-pentamethyldisilanyl-2-trimethylsilyl-2-dimethylsilyl-
ethane, 4. This compound was isolated from entry 4-4 (Table 1).
Colorless oil, bp 60-75 °C/0.44 mmHg (Kugelrohr). 1H NMR
3
(benzene-d6, 300 MHz): δ -0.01 (d, JHSiCH = 3.8 Hz, 3H,
Typical Procedure for AlCl3-Catalyzed Reactions of Alkynes
with Hydropolysilanes: Reaction of 5-Decyne with Pentamethyl-
disilane, Forming (Z)-5-Pentamethyldisilanyl-5-decene. To AlCl3
(0.100 mmol) and dichloromethane (0.5 mL) placed in a Schlenk
tube kept at 0 °C were added pentamethyldisilane (1a) (1.00
mmol) and a dichloromethane (0.5 mL) solution of 5-decyne
(2A) (1.00 mmol). The mixture was stirred at that temperature
for 1 h and was quenched with triethylamine (0.2 mL) and
saturated aqueous NaHCO3 (1.0 mL). The organic phase was
analyzed by GC after addition of n-dodecane as internal stan-
dard. After GC and GC-MS analyses, the mixture was sepa-
rated, the aqueous phase was extracted with hexane (2 mL ꢀ 4
times), and the combined organic phase was washed with brine
(5 mL) and dried over sodium sulfate. The filtrate of the dried
solution was evaporated to leave a nearly pure sample, which
was further purified by column chromatography (silica gel,
hexane) to give (Z)-3aA as a colorless oil in 80% yield.
SiMeH), 0.01 (s, 9H, SiSiMe3), 0.02 (s, 9H, CSiMe3), 0.16 (d,
3JHSiCH = 3.8 Hz, 3H, SiMeH), 0.26 (s, 3H, SiMeSiMe3), 0.29
(s, 3H, SiMeSiMe3), 0.60 (d, 3JHCCH = 1.5 Hz, 1H, CHSi2), 2.77
(d, 3JHCCH = 1.5 Hz, 1H, PhCH), 4.74 (sept, 3JHSiCH = 3.8 Hz,
1H, SiH), 6.99 (t, 3JHCCH = 7.4 Hz, 1H, p-Ph), 7.09 (m, 2H, m-
3
Ph), 7.33 (d, JHCCH = 7.4 Hz, 2H, o-Ph). 13C{1H} NMR
(benzene-d6, 75 MHz): δ -3.1, -2.6, -1.5 (3), -1.5 (9), -0.5,
1.1 (SiMe ꢀ 6), 17.4 (PhCHC), 34.2 (PhC), 125.8, 128.4, 130.5,
144.8. 29Si NMR (CDCl3, 60 MHz): δ -18.8, -12.9, -10.8, 5.1.
GC-MS (20 eV): m/z (% relative intensity) 366 ([M]þ, 6), 293
([M - Me]þ, 100), 234 (61), 220 (20), 205 (14), 193 (19), 161 (95),
146 (16), 135 (22), 131 ([SiMe2SiMe3]þ, 71), 73 (18). HRMS (EI):
calcd for C18H38Si4 m/z 366.2051, found 366.2057.
(Z)-1-Pentamethyldisilanyl-5-chloro-1-pentene, (Z)-3aE. Col-
orless oil, bp 37-46 °C/0.38 mmHg (Kugelrohr). 1H NMR
(CDCl3, 300 MHz): δ 0.07 (s, 9H, SiMe3), 0.18 (s, 6H, SiMe2),
3
1.86 (quint, JHCCH = 7.1 Hz, 2H, CH2CH2CH2), 2.23 (ddt,
3JHCCH=7.1 Hz, 3JHCCH=7.1 Hz, 4JHCCCH=1.2 Hz, 2H, CH2CHd
(Z)-5-Pentamethyldisilanyl-5-decene, (Z)-3aA. Colorless oil.
1H NMR (CDCl3): δ 0.06 (s, 9H, SiMe3), 0.17 (s, 6H, SiMe2),
0.89 (t, 3JHCCH = 6.8 Hz, 3H, CH3), 0.90 (t, 3JHCCH = 6.8 Hz, 3H,
CH3), 1.25-1.34 (m, 8H (CH2)2CH2C(Si)dCHCH2(CH2)2), 2.01
3
CH), 3.54 (t, JHCCH = 7.1 Hz, 2H, ClCH2), 5.55 (dt, JHCCH
3
=
=
4
3
13.7 Hz, JHCCCH =1.2 Hz, 1H, CHdCHSi), 6.28 (dt, JHCCH
3
13.7 Hz, JHCCH = 7.1 Hz, 1H, CH2CHdCH). 13C{1H} NMR
(CDCl3, 75 MHz): δ -2.6, -2.0, 31.3, 32.7, 44.5, 129.4, 146.4. 29Si
NMR (CDCl3, 60 MHz): δ -28.9, -18.8. IR (neat, cm-1): 2993,
2952, 2895, 2844, 1604, 1444, 1398, 1246, 833, 802, 768, 725, 690. GC-
MS (20 eV): m/z (% relative intensity) 219 ([M - Me]þ, 2), 161 ([M
- TMS]þ, 1), 126 (4), 111 (63), 98 (93), 93 (42), 83 (7), 73 ([TMS]þ,
100), 66 (5), 59 (10). HRMS(EI):calcdfor C9H20ClSi2 (value for [M
- Me]þ) m/z 219.0792, found 219.0790.
(t, 3JHCCH = 6.0 Hz, 2H, CH2CHdC(Si)CH2), 2.03 (d, 3JHCCH
=
7.1 Hz, 2H, CH2CHdC(Si)CH2), 5.94 (t, 3JHCCH = 7.1 Hz, 1H,
CH). 13C{1H} NMR (CDCl3): δ -2.46, -1.57, 14.04, 14.13, 22.50,
22.59, 32.54, 32.74, 33.33, 38.21, 138.09, 142.46. 29Si NMR
(CDCl3) δ -26.09, -18.68. IR (neat, cm-1): 2954, 1610, 1457,
835, 800. GC-MS m/z (% relative intensity): 270 ([M]þ, 24), 197
([M - SiMe3]þ, 100), 141 (30), 127 (46), 113 (32), 99 (31), 87 (12),
73 (45), 59 (11). Anal. Calcd for C15H34Si2: C, 66.58; H, 12.66.
Found: C, 66.44; H, 12.50.
(Z)-β-Pentamethyldisilanyl-p-methoxystyrene, (Z)-3aF. Col-
1
orless oil, bp 37.0-41.3 °C/0.053-0.068 mmHg (Kugelrohr). H
NMR (C6D6, 300 MHz): δ 0.13 (s, 9H, SiMe3), 0.24 (s, 6H, SiMe2),
3.27 (s, CH3O), 5.83 (d, 3JHCCH=14.8 Hz, 1H, CdCHSi), 6.78 (d,
3JHCCH =8.48 Hz, 2H, phenylene o-protons with respect to me-
thoxy), 7.27 (d, 3JHCCH=8.48 Hz, 2H, phenylene m-protons with
(Z)-1-(Pentamethyldisilanyl)stilbene, (Z)-3aB. Colorless oil.
1H NMR (CDCl3): δ -0.04 (s, 6H, SiMe2), 0.01 (s, 9H, SiMe3),
7.18-7.39 (m, 10H, 2Ph), 7.33 (s, 1H, CH). 13C{1H} NMR
(CDCl3): δ -1.54, -1.46, 125.71, 127.16, 127.25, 127.92, 127.98,
128.62, 139.78, 144.84, 146.37, 147.62. 29Si NMR (CDCl3): δ
-23.78, -17.88. IR (neat, cm-1): 3064, 2954, 1589, 1490, 833,
802. GC-MS m/z (% relative intensity): 310 ([M]þ, 4), 237 ([M -
SiMe3]þ, 100), 221 (15), 207 (3), 159 (22), 135 (34), 121 (7), 73 (4),
59 (7). Anal. Calcd for C19H26Si2: C, 73.48; H, 8.44. Found: C,
73.76; H, 8.57.
3
respect to methoxy), 7.39 (d, JHCCH = 14.8 Hz, 1H, SiCd
CH). 13C{1H} NMR (C6D6, 75 MHz): δ -1.7, -1.5, 54.8, 113.8,
129.2, 129.9, 133.1, 146.6, 159.8. 29Si NMR (C6D6, 60 MHz): δ
-18.7, -28.2. IR (neat, cm-1): 3031, 3001, 2952, 2895, 2835, 1608,
1508 1464, 1442, 1417, 1302, 1253, 1173, 1111, 1038, 833, 802,
727, 690, 617, 586, 521. GC-MS m/z (% relative intensity): 264
([M]þ, 33), 249 ([M - Me]þ, 68), 234 ([M - 2Me]þ, 11), 191 ([M -
TMS]þ, 100), 175 (79), 165 (76), 145 (32), 135 (16), 131
(Me3SiMe2Siþ, 10), 89 (13), 73 (72), 59 (56). HRMS (EI): calcd
for C14H24OSi2 m/z 264.1366, found 264.1366.
(Z)-1-Pentamethyldisilanyl-1-decene, (Z)-3aC. Colorless oil.
1H NMR (CDCl3): δ 0.06 (s, 9H, SiMe3), 0.16 (s, 6H, SiMe2),
3
0.88 (t, JHCCH = 6.4 Hz, 3H, CH3CH2), 1.28-1.36 (m, 12H,
3
(CH2)6), 2.07 (dt, JHCCH=6.9 Hz, 3JHCCH=7.0 Hz, 2H, CH3-
3
1-tert-Butylphenyl-1-pentamethyldisilanyl-2-trimethylsilyl-2-
dimethylsilylethane, 40. The reaction of p-tert-butylphenylacetylene
(1.0 mmol) with 2 equiv of 1a was run using the typical procedure.
Column chromatography (silica gel, gradient mixture of hexane
with increasing portion of dichloromethane) afforded this product
(166 mg, 40%). White prism, mp 48.9-50.2 °C. 1H NMR
(benzene-d6, 300 MHz): δ 0.01-0.03 (m, 12H, SiMeH þ SiSiMe3),
0.06 (s, 9H, CSiMe3), 0.19 (d, 3JHSiCH = 3.7 Hz, 3H, SiMeH), 0.24
(s, 3H, SiMeSiMe3), 0.31 (s, 3H, SiMeSiMe3), 0.62 (br s, 1H,
CHSi2), 2.80 (br s, 1H, PhCH), 4.80 (sept, 3JHSiCH = 3.7 Hz, 1H,
(CH2)6CH2), 5.46 (d, JHCCH = 13.7 Hz, 1H, CH2CHdCHSi-
Me2), 6.32 (dt, 3JHCCH=13.7 Hz, 3JHCCH=7.0 Hz, 1H, (Si)CHd
CHCH2). 13C{1H} NMR (CDCl3): δ -2.51, -2.06, 14.11, 22.68,
29.27, 29.47, 29.58, 29.90, 31.88, 34.24, 127.37, 149.10. 29Si NMR
(CDCl3): δ -29.28, -18.30. IR (neat, cm-1): 2952, 2857, 1602,
1457, 725, 690. GC-MS m/z (% relative intensity): 270 ([M]þ, 7),
255 ([M - Me]þ, 7), 196 ([M - SiMe3 - 1]þ, 100), 181 ([M -
SiMe3 - Me - 1]þ, 20), 168 (18), 139 (15), 131 (9), 125 (16), 99 (33),
81 (14), 73 (61), 59 (26). HRMS (EI): calcd for C15H34Si2 m/z
270.2199, found 270.2200. Anal. Calcd for C15H34Si2: C, 66.58; H,
12.66. Found: C, 66.42; H, 12.68.
3
SiH), 7.21 (d, JHCCH = 8.1 Hz, 2H, phenylene m-protons with
respect to tBu), 7.34 (d, 3JHCCH = 8.1 Hz, 2H, phenylene o-protons
with respect to tBu). 13C{1H} NMR (benzene-d6, 75 MHz): δ -3.1,
-2.6, -1.6, -1.5, -0.5, 1.1 (SiMe ꢀ 6), 17.2 (PhCHC), 31.5
(CMe3), 33.4 (PhC), 34.3 (CMe3) 125.2, 130.2, 141.6, 148.6. 29Si
NMR (benzene-d6, 60 MHz): δ -18.9, -12.7, -10.8, 5.0. GC-MS
(Z)-β-(Pentamethyldisilanyl)styrene, (Z)-3aD. This com-
pound was isolated from entry 4-5 (Table 1). Colorless oil. H
1
NMR (CDCl3): δ 0.03 (s, 9H, SiMe3), 0.11 (s, 6H, SiMe2), 5.85
(d, 3JHCCH=14.7 Hz, 1H, CHSiCH2), 7.23-7.34 (m, 5H, Ph),
7.37 (d, 3JHCCH=14.7 Hz, 1H, CHPh). 13C{1H} NMR (CDCl3):

Article
Organometallics, Vol. 29, No. 21, 2010 5281
(20eV):m/z(% relative intensity) 422 ([M]þ, 2), 349([M- TMS]þ,
100), 291 ([M - SiMe2SiMe3]þ, 57), 249 (24), 233 (84), 217 (41),
191 (52), 161 (17), 145 (34), 131 ([SiMe2SiMe3]þ, 20), 73 (34), 57
([SiMe2H]þ, 77). HRMS (FAB, 2-nitrobenzyl alcohol): calcd for
C22H45Si4 (value for [M - H]þ) m/z 421.2598, found 421.2593.
(Z)-1-(2-Phenyl-1,1,2,2-tetramethydisilanyl)-1-decene, (Z)-3bC.
Colorless oil, bp 92-105 °C/0.61 mmHg (Kugelrohr). 1H NMR
(CDCl3, 300 MHz): δ 0.16 (s, 6H, SiMe2SiMe2Ph), 0.35 (s, 6H,
SiMe2Ph), 0.89 (t, 3JHCCH = 6.6 Hz, 3H, CH3CH2), 1.22-1.41
(m, 12H, 6CH2), 1.95 (dt, 3JHCCH=7.1 Hz, 3JHCCH=7.1 Hz, 2H,
CH2CHdCH), 5.44 (d, 3JHCCH=13.7 Hz, 1H, CHdCHSi), 6.31
(dt, 3JHCCH = 13.7 Hz, 3JHCCH=7.1 Hz, 1H, CH2CH=CH),
7.30-7.32 (m, 3H, o- and p-H), 7.44-7.47 (m, 2H, m-H). 13C-
{1H} NMR (CDCl3, 75 MHz): δ -3.7 -2.3, 14.1, 22.7, 29.3,
29.4, 29.5, 29.8, 31.9, 34.2, 126.7, 127.6, 128.3, 133.9, 139.6,
149.7. 29Si NMR (CDCl3, 60 MHz): δ -29.0, -21.2. IR (neat,
cm-1): 3068, 3051, 2956, 2925, 2854, 1603, 1466, 1427, 1244,
1105, 831, 822, 795, 771, 731, 698, 648. GC-MS m/z (% relative
intensity): 332 ([M]þ, 8), 317 ([M - Me]þ, 5), 259 (45), 197 (25),
135 (100), 121 (35), 99 (13), 73 (16), 59 (40). HRMS (FAB,
2-nitrobenzyl alcohol): calcd for C20H36Si2 m/z 332.2356, found
332.2355.
2CH3CH2), 1.09-1.27 (m, 24H, 12CH2), 2.07 (apparent dt,
3
3JHCCH=6.8 Hz, JHCCH=6.9 Hz, 4H, 2CH2CHdCH), 5.46
(dt, JHCCH=13.7 Hz, JHCCCH = 1.2 Hz, 2H, 2CHdCHSi),
2
4
3
3
6.31 (dt, JHCCH=13.8 Hz, JHCCH=6.9 Hz, 2H, 2CH2CHd
CH). 13C{1H} NMR (CDCl3, 75 MHz): δ -6.1, -1.4, 14.1, 22.7,
29.3, 29.5, 29.6, 30.0, 31.9, 34.1, 127.8, 148.9. 29Si NMR (CDCl3,
60 MHz): δ -46.8, -25.5. GC-MS m/z (% relative intensity):
452 ([M]þ, 8), 393 (6), 379 (12), 321 (7), 255 ([M - SiMe2-
(C10H19)]þ, 24), 241 (15), 181 (34), 155 (24), 141 (36), 116 (65), 97
(29), 73 ([TMS]þ, 90), 59 (100).
(E)-1-Pentamethyldisilanylmethylene-2-cyclohexene, 9. Col-
orless oil. 1H NMR (CDCl3, 300 MHz): δ 0.06 (s, 9H, SiMe3),
0.15 (s, 6H, SiMe2), 1.71 (apparent quint, 3JHCCH = 6.2 Hz, 2H,
H-6), 2.08-2.14 (m, 2H, H-5), 2.36 (m, 2H, H-7), 5.27 (br s, 1H,
3
3
H-1), 5.79 (dt, JHCCH=4.5 Hz, JHCCH = 9.8 Hz, 1H, H-4),
6.09 (apparent dt, 3JHCCH=9.8 Hz, 4JHCCCH=1.8 Hz, 1H, H-3).
13C{1H} NMR (CDCl3, 75 MHz): δ -2.7 (SiMe3), -1.9
(SiMe2), 23.0 (C-6), 25.2 (C-5), 30.9 (C-7), 124.9 (C-1), 129.6
(C-4), 132.9 (C-3), 151.6 (C-2). 29Si NMR (CDCl3, 60 MHz): δ
-18.4, -29.3. IR (neat, cm-1): 2948, 2895, 1712, 1684, 1576,
1429, 1394, 1246, 1065, 837, 808, 791, 690. GC-MS m/z (%
relative intensity): 224 ([M]þ, 54), 209 ([M - Me]þ, 18), 165 (18),
135 (100), 131 ([SiMe2SiMe3]þ, 24), 123 (43), 109 (18), 95 (20), 91
(20), 85 (27), 78 (10), 73 (99), 59 (91). HRMS (EI): calcd for
C12H24Si2 m/z 224.1417, found 224.1423. A NOE experiment
was performed by irradiation of a signal at 5.27 ppm (Scheme 9).
Hydrosilylation Polymerization of 1,7-Octadiyne with 1,3-
Dihydrohexamethyltrisilane. To AlCl3 (1.00 mmol) and dichlor-
omethane (1.0 mL) placed in a Schlenk tube kept at 0 °C was
added 1,3-dihydrohexamethyltrisilane (1f) (1.00 mmol), and the
mixture was stirred for 7 min at that temperature. 1,7-Octadiyne
(2J) (1.00 mmol) was added to the mixture. The resulting
mixture was stirred for 65 h at that temperature and quenched
with triethylamine (0.2 mL) and saturated aqueous NaHCO3
(1.0 mL). The organic phase was analyzed by GC after addition
of biphenyl as internal standard. After GC and GC-MS
analyses, the mixture was separated, the aqueous phase was
extracted with dichloromethane (1 mL ꢀ 4 times), and the
combined organic phase was washed with brine (5 mL) and
dried over sodium sulfate. The filtrate of the dried solution was
evaporated to leave 0.26 g of a residue, which was analyzed by
NMR spectroscopy. Then the residue was dissolved in dichloro-
methane (5 mL) and the solution was poured into methanol
(100 mL) to develop a suspension, which was separated by
decantation to give 0.08 g of a solid material (poly-10fJ) and
also 0.2 g of liquid material after evaporation of the liquid phase.
Poly-10fJ. 1H NMR (CDCl3, 300 MHz) obtained for the solid
material (intensities given are observed values, relative to 12H
assignable to SiMe2SiMe2SiMe2 at 0.19 ppm): δ ∼0.10 (s, 5.0H,
SiMe2SiMe2SiMe2), ∼0.19 (s, 12H, SiMe2SiMe2SiMe2),
1.26-1.38 (br m, 7.2H, CH2CH2CH2CH2, perhaps overlapping
with other unknown signals), 2.07 (apparent br d, 3.9H
CH2CH2CH2CH2), 5.47 (d, 1.7H, 2SiMe2CH), 6.32 (dt, 1.6H,
2SiCHdCH). Besides these signals, the spectrum displayed
unidentified signals at 0.88 and 2.2-2.7 ppm.
(Z)-1-Heptamethyltrisilanyl-1-decene, (Z)-3cC. Colorless oil.
1H NMR (CDCl3): δ 0.08 (s, 9H, SiMe3), 0.09 (s, 6H, SiMe2-
SiMe3), 0.20 (s, 6H, CdCHSiMe2), 0.88 (t, JHCCH = 6.7 Hz,
3
3H, CCH3), 1.35-1.53 (m, 12H, (CH2)6), 2.08 (dt, 3JHCCH = 7.0
=
Hz, 3JHCCH = 6.8 Hz, 2H, SiCHdCHCH2), 5.47 (d, 3JHCCH
3
13.7 Hz, 1H, SiCHdCHCH2), 6.31 (dt, JHCCH = 7.0 Hz,
3JHCCH = 13.7 Hz, 1H, SiCHdCHCH2). 13C{1H} NMR
(CDCl3): δ -6.63, -1.49, -1.45, 14.12, 22.68, 29.28, 29.47,
29.58, 29.94, 31.88, 34.12, 127.73, 148.91. 29Si NMR (CDCl3): δ
-47.67, -25.78, -15.58. IR (neat, cm-1): 2950, 1602, 1460, 725,
688. GC-MS m/z (% relative intensity): 328 ([M]þ, 10), 313
([M - Me]þ, 3), 269 (5), 255 (10), 239 (4), 197(6), 181 (11), 155
(7), 141 (8), 131 ([SiMe2SiMe3]þ, 32), 116 ([SiMe2SiMe2]þ, 100),
99 (6), 73 (15), 59 (4). Anal. Calcd for C17H40Si3: C, 62.11; H,
12.26. Found: C, 61.92; H, 12.28.
(Z)-1-Nonamethyltetrasilanyl-1-decene, (Z)-3dC. Colorless
oil, bp 84-130 °C/0.56 mmHg (Kuhgelrohr). 1H NMR
(CDCl3, 300 MHz): δ 0.08 (s, 9H, SiMe3), 0.11 (s, 6H, SiMe2),
0.13 (s, 6H, SiMe2), 0.21 (s, 6H, CHSiMe2), 0.88 (t, 3JHCCH
=
6.4 Hz, 3H, CH3CH2), 1.22-1.41 (m, 12H, (CH2)6), 2.08 (dt,
3JHCCH = 7.0 Hz, 3JHCCH = 7.0 Hz, 2H, CH2CHdCH), 5.47
(d, 3JHCCH = 13.7 Hz, 1H, CHdCHSi), 6.31 (dt, 3JHCCH = 13.7
3
Hz, JHCCH = 7.0 Hz, 1H, CH2CHdCH). 13C{1H} NMR
(CDCl3, 75 MHz): δ -5.9, -5.4, -1.3, 14.1, 22.7, 29.3, 29.5,
29.6, 29.7, 29.9, 31.9, 34.1, 127.8, 149.0. 29Si NMR (CDCl3, 60
MHz): δ -44.4, -43.1, -24.9, -15.0. GC-MS m/z (% relative
intensity): 386 ([M]þ, 15), 313 ([M - TMS]þ, 11), 238 (11), 189
([M - SiMe2SiMe2SiMe3]þ, 30), 174 ([SiMe2SiMe2SiMe2]þ,
100), 159 (13), 141 (13), 131 ([SiMe2SiMe3]þ, 39), 129 (25), 117
(18), 99 (10), 73 ([TMS]þ, 76), 59 (34). Anal. Calcd for
C19H42Si4: C, 58.98; H, 11.98. Found: C, 59.12; H, 12.00.
1,2-Di[(Z)-1-decen-1-yl]tetramethyldisilane, (Z,Z)-8eC. Col-
1
orless oil, bp 101-118 °C/0.11 mmHg (Kugelrohr). H NMR
=
(CDCl3, 300 MHz): δ 0.18 (s, 12H, 2SiMe2), 0.88 (t, 3JHCCH
1-[(Z)-(1-Decen-1-yl)]-1,1,2,3,3-pentamethyltrisilane, 11-I. This
1
compound was isolated by preparative HPLC. Colorless oil. H
6.4 Hz, 6H, 2CH3CH2), 1.22-1.41 (m, 24H, 12CH2), 2.07 (dt,
3JH3CCH = 7.2 Hz, 3JHCCH = 7.2 Hz, 4H, 2CH2CHdCH), 5.46
NMR (CDCl3, 300 MHz): δ 0.15 (d, 3H, JHCSiH = 5.1 Hz,
3
3
3
4
(d, JHCCH = 13.7 Hz, 2H, 2CHdCHSi), 6.32 (dt, JHCCH
=
SiSiMeSi), 0.18 (dd, 3H, JHCSiH =4.5 Hz, JHCSiSiH =1.5 Hz,
SiSiSiHMe), 0.19 (d, 3H, J = 0.7 Hz, SiSiSiHMe), 0.21 (d, 3H,
4JHCSiSiH = 0.5 Hz, SiHSiHSiMe), 0.25 (s, 3H, SiHSiHSiMe), 0.88
(t, 3H, 3JHCCH=6.6 Hz, CH3CH2), 1.18-1.43 (br, 12H, 6CH2),
13.7 Hz, 3JHCCH = 7.2 Hz, 2H, 2CH2CHdCH). 13C{1H} NMR
(CDCl3, 75 MHz): δ -2.1, 14.1, 22.7, 29.3, 29.5, 29.6, 29.9, 31.9,
34.2, 127.4, 149.2. 29Si NMR (CDCl3, 60 MHz): δ -28.7. GC-
MS m/z (% relative intensity): 394 ([M]þ, 3), 379 ([M - Me]þ, 2),
321 (43), 255 ([M - C10H19]þ, 10), 197 ([M/2]þ, 45), 181 (10), 141
(10), 116 ([Si2Me4]þ, 5), 111 (25), 99 (36), 73 ([TMS]þ, 46), 59
(100). Anal. Calcd for C24H50Si2: C, 73.01; H, 12.76. Found: C,
72.79; H, 12.59.
3
3
2.11 (dt, 2H, JHCCH =7.0 Hz, JHCCH =7.1 Hz, CdC-CH2),
3.17-3.22 (m, 1H, SiSiHSi), 3.80-3.86 (d-sept, 1H, 3JHSiCH = 4.5
Hz, 3JHSiSiH = 1.5 Hz, SiSiSiH), 5.50 (dt, 1H, 3JHCCH = 12.9 Hz,
4JHCCCH = 1.4 Hz, SiCHdC), 6.33 (dt, 1H, 3JHCCH = 12.9 Hz,
3JHCCH = 7.1 Hz, C=CHC). IR (neat, cm-1): 2958, 2927, 2856,
2131, 1716, 1606, 1466, 1410, 1379, 1257, 1057, 908, 879, 837, 798,
771. GC-MS m/z (% relative intensity): 300 ([M]þ, 15), 255 (16),
241 ([M - SiHMe2]þ, 14), 197 (30), 181 (23), 160 (16), 155 (18), 141
1,3-Di[(Z)-1-decen-1-yl]hexamethyltrisilane, (Z,Z)-8fC. 1H
NMR (CDCl3, 300 MHz): δ 0.11 (s, 6H, SiMe2SiMe2SiMe2,),
0.20 (s, 12H, SiMe2SiMe2SiMe2), 0.88 (t, 3JHCCH = 6.6 Hz, 6H,

5282 Organometallics, Vol. 29, No. 21, 2010
Kato et al.
(40), 127 (30), 116 (70), 102 (89), 97 (37), 83 (14), 73 (79), 59 (100).
HRMS (EI): calcd for C15H36Si3 m/z 300.2125, found 300.2122.
1,2-Di[(Z)-(1-decen-1-yl)]-1,1,2,3,3-pentamethyltrisilane, 11-
II-a, and 1,3-Di[(Z)-(1-decen-1-yl)]-1,1,2,3,3-pentamethyltri-
silane, 11-II-b. Since separation of an approximately 1:1 mixture
of 11-II-a and 11-II-b, isolated by preparative HPLC, was not
possible, NMR and HRMS analyses were made for the mixture.
Colorless oil. 1H NMR (CDCl3, 300 MHz): δ 0.12-0.25
Reaction of Poly(phenylsilylene) with 1-Decyne. The reaction
of poly(phenylsilylene) (1i) (Mw=2697, Mw/Mn=1.63 as ana-
lyzed by GPC with polystyrene standards) with 1-decyne (2C)
(1 equiv relative to a SiHPh repeat unit in the polymer) was run
at 0 °C in CH2Cl2 using AlCl3 (10 mol % relative to 1-decyne) for
26 h. Quenching with triethylamine and aqueous sodium bicar-
bonate, extraction with CH2Cl2, drying over sodium sulfate,
filtration through a Florisil column, and evaporation of the
filtrate gave product polymer 12 (190 mg) as a pale yellow oil.
The oily material was fractionated by preparative HPLC to
isolate higher molecular weight fraction 120 as a sticky oil (84
mg). Molecular weight and extent of introduction of decenyl
units were analyzed by GPC and 1H NMR spectroscopy.
Higher Molecular Weight Fraction 120 of the Polymer Ob-
tained from the Reaction of Poly(phenylsilylene) with 1-Decyne.
Pale yellow sticky oil. 1H NMR (CD2Cl2, 300 MHz): δ 0.2-2.9
(br, alkyl-H), 3.7-4.5 (br, SiH), 4.5-6.0 (br, alkenyl-H),
6.0-8.1 (br, Ph). IR (neat, cm1): 3066, 3049, 2954, 2929, 2918,
2852, 2104, 1593, 1483, 1466, 1427, 1377, 1134, 1101, 1066, 1028,
997, 735, 698.
3
(m, 15H, 5SiMe), 0.88 (t, 6H, JHCCH = 6.6 Hz, 2CH3CH2),
1.20-1.41 (br, 24H, 12CH2), 2.02-2.15 (m, 4H, 2CdC-CH2),
3.20 (quart, 0.5H, 3JHSiCH = 5.2 Hz, 0.5SiSiHSi in 11-II-b), 3.82
(sept, 0.5H, 3JHSiCH = 4.5 Hz, 0.5SiSiSiH, 11-II-a), 5.43-5.51
(m, 2H, 2SiCHdC), 6.23-6.34 (m, 2H, 2CdCHC). IR (neat,
cm-1): 2956, 2925, 2854, 2087, 1603, 1466, 1408, 1377, 1244, 874,
837, 777, 688. HRMS (EI): calcd for C25H54Si3 438.3533, found
438.3539.
1,2,3-Tri[(Z)-(1-decen-1-yl)]-1,1,2,3,3-pentamethyltrisilane,
11-III. This compound was isolated by preparative HPLC.
Colorless oil. 1H NMR (CDCl3, 300 MHz): δ 0.22 (s, 6H,
2SiSiSiMe), 0.23 (s, 6H, 2SiSiSiMe), 0.26 (s, 3H, SiSiMeSi), 0.88
(t, 9H, 3JHCCH=6.6 Hz, CH3CH2), 1.17-1.42 (br, 36H, 18CH2),
2.00-2.12 (m, 6H, 3CdC-CH2), 5.45 (dt, 1H, 3JHCCH=13.6 Hz,
Acknowledgment. This work was supported by a
Grant-in-Aid for Scientific Research (No. 21605005)
from the Ministry of Education, Culture, Sports, Science
and Technology, Japan.
3
4JHCCCH =1.2 Hz, SiCHdC), 5.75 (dt, 2H, JHCCH =13.6 Hz,
3
4JHCCCH=1.2 Hz, 2SiCHdC), 6.30 (dt, 3H, JHCCH=13.6 Hz,
3JHCCH=7.6 Hz, 3CdCHC). 13C{1H} NMR (CDCl3, 75 MHz):
δ -6.1 (SiSiMeSi), -0.9 (SiSiSiMe ꢀ 2), 14.1, 22.7, 29,3, 29.57,
29.59, 29.63, 29.93, 31.9, 34.1, 34.7, 124.2, 127.8, 149.0, 149.1. 29Si
NMR (CDCl3, 60 MHz): δ -25.0, -54.6. IR (neat, cm-1): 2956,
2927, 2854, 1603, 1466, 1244, 1045, 837, 819, 773, 687. GC-MS m/z
(% relative intensity): 463 ([M - C8H17]þ, 43), 379 (19), 321 (10),
311 (11), 267 (13), 253 (19), 241 (17), 225 (10), 197 (20), 181 (27),
169 (13), 155 (32), 141 (46), 131 (14), 127 (26), 117 (33), 111 (27),
103 (12), 97 (39), 85 (24), 73 (50), 59 (100). HRMS (EI): calcd for
C35H72Si3 576.4942, found 576.4948.
Supporting Information Available: Experimental details,
spectral and/or analytical data of minor products (E)-3aA,
(E)-3aC, r-3aC, r-3aE, (E)-3aF, 3aF-saturated, 5, 6, (Z)-3aD0,
(Z,r)-8eC, 1bG, 1bG-(SiMe2)2H, 11-II-a, and 11-II-b, NMR
spectra of products, and crystallographic data for 40 in CIF
format. This material is available free of charge via the Internet
at http://pubs.acs.org.