Effect of catalysts on the reaction of allyl esters with hydrosilanes

Article abstract of DOI:10.1134/S1070363210040079

The reaction of hydrosilylation of allyl esters XOCH ₂CH=CH ₂ (X = MeCO, CF ₃CO, C ₃F ₇CO) and PhOCH ₂CH=CH ₂ with hydrosilanes HSiY ₃ (Y = Cl, OEt) in the presence of the Speier catalyst, the Speier catalyst with additives, and of various nickel complexes was studied. The catalytic hydrosilylation reaction in the presence of the Speier catalyst is accompanied by the reduction. Additives to the Speier catalyst (vinyltriethoxysilane and some ethers) allow to suppress considerably the reduction reaction. In the presence of the studied nickel complexes mainly reduction and isomerization reactions occurred. The best nickel catalysts of hydrosilylation were the mixtures of NiCl ₂ or Ni(acac) ₂ with phosphine oxides. In contrast to allyl esters, the hydrosilylation of simple olefins proceeds easier, the content of the product of hydrosilylation in the reaction mixture reaches 94.3%. Pleiades Publishing, Ltd., 2010.

Full text of DOI:10.1134/S1070363210040079

ISSN 1070-3632, Russian Journal of General Chemistry, 2010, Vol. 80, No. 4, pp. 728–733. © Pleiades Publishing, Ltd., 2010.
Original Russian Text © Z.V. Belyakova, M.G. Pomerantseva, L.A. Efimova, E.A. Chernyshev, P.A. Storozhenko, 2010, published in Zhurnal Obshchei
Khimii, 2010, Vol. 80, No. 4, pp. 568–572.
Effect of Catalysts on the Reaction of Allyl Esters
with Hydrosilanes
Z. V. Belyakova, M. G. Pomerantseva, L. A. Efimova,
E. A. Chernyshev, and P. A. Storozhenko
State Scientific and Research Institute of Chemistry and Technology of Organoelemental Compounds,
sh. Entuziastov 38, Moscow, 111123 Russia
e-mail: eos2004@inbox.ru
Received June 25, 2009
Abstract―The reaction of hydrosilylation of allyl esters XOCH2CH=CH2 (X = MeCO, CF3CO, C3F7CO) and
PhOCH2CH=CH2 with hydrosilanes HSiY3 (Y = Cl, OEt) in the presence of the Speier catalyst, the Speier
catalyst with additives, and of various nickel complexes was studied. The catalytic hydrosilylation reaction in
the presence of the Speier catalyst is accompanied by the reduction. Additives to the Speier catalyst
(vinyltriethoxysilane and some ethers) allow to suppress considerably the reduction reaction. In the presence of
the studied nickel complexes mainly reduction and isomerization reactions occurred. The best nickel catalysts
of hydrosilylation were the mixtures of NiCl2 or Ni(acac)2 with phosphine oxides. In contrast to allyl esters, the
hydrosilylation of simple olefins proceeds easier, the content of the product of hydrosilylation in the reaction
mixture reaches 94.3%.
DOI: 10.1134/S1070363210040079
The reactions of hydrosilylation [Eq. (1)] of allyl
esters in the presence of the Speier catalyst occurred
with different yields (19–70%) [1–3] and often were
accompanied with side reduction [Eq. (2)], and
isomerization [Eq. (3)] reactions.
formed at preliminary heating of the Speier catalyst
with allyl acetate (Table 1). The absence of tetra-
ethoxysilane in the product shows that reduction
reaction is suppressed.
Tetraethoxysilane is formed from the product of
reduction by disproportion.
XCH2CH=CH2 + HSiY3 → X (CH2)3 SiY3,
XCH2CH=CH2 + HSiY3 → XSiY3 + C3H6,
XCH2CH=CH2 → XCH=CH2CH3,
(1)
(2)
(3)
2XSi(OEt)3 → X2Si(OEt)2 + Si(OEt)4.
(4)
At the hydrosilylation of allyl acetate the amount of
tetraethoxysilane increases due to the reduction of
acetoxy group in the acetoxytriethoxysilane.
X = MeCOO, CF3COO, C3F7COO, CH2=C(CH3)COO, Ph;
Y = Cl, OEt.
MeCOOSi(OEt)3 + HSi(OEt)3 → Si(OEt)4.
(5)
In this work we studied the influence of certain
additives to the Speier and nickel catalysts on the
course of the main and side reactions in the hydro-
silylation of allyl esters and ethers.
We showed that at the hydrosilylation of allyl
acetate with triethoxysilane in the presence of the
Speier catalyst with the addition of vinyltriethoxy-
silane the yield of acetoxypropyltriethoxysilane in-
creased compared to the reaction without additives,
from 84.3 to 88.7%, while the content of tetra-
ethoxysilane fell from 8.8 to 0%. Tetraethoxysilane
also is not formed when the hydrosilylation of allyl
acetate was carried out in the presence of catalysts
Hydrosilylation of allyl phenyl ether in the presence
of the Speier catalyst proceeded with the 70% yield
[3]. Additives of vinyltriethoxysilane to the Speier
catalyst significantly affect the reaction: the yield of γ-
phenoxypropyltriethoxysilane increases up to 85% and
the molar ratio of the addition product to the reduction
product ADD/RED grows from 8.99 to 19.83 (Table 1).
Similar situation is observed in the hydrosilylation of
allyl methacrylate: adduct yield increases from 67 to
82%, and ADD/RED from 5.55 to 11.44%.
The process of hydrosilylation of allyl trifluoro-
acetate and allyl perfluorobutyrate was not affected by
728

EFFECT OF CATALYSTS ON THE REACTION OF ALLYL ESTERS
729
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 80 No. 4 2010

730
BELYAKOVA et al.
the addition of the vinyltriethoxysilane. This difference
in the behavior of allyl trifluoroacetate and allyl
perfluorobutyrate from allyl acetate is explained
apparently by the difference in the ability of these
reagents to the reaction of displacement of the vinyl
ligand in the platinum-olefin complex. Trifluoroacetate
addition to the Speier catalyst at the hydrosilylation of
allyl acetate only reduces the reaction rate but does not
exclude reduction.
Ni(1,5-cod)2 (VII), Ni (1,5-cod)·(DQ)1 (VIII), Ni(DQ)2
(IX), Ni(C10H12)2·(DQ) (X), Ni(TCC)2 (XI); hydride
3
complexes: HNi(PPh3)2Br (XII), HNi[P(C6H11)3]2Br
(XIII); alkyl complex EtNi[P(C6H11)3](acac) (XIV), as
well as some of these complexes and NiCl2 (XV), Ni
(acac)2 (XVI) mixed with the additives PPh3 (XVII),
CuCl (XVIII), and phosphine oxides Oct3P=O (XIX),
MePh2P=O (XX), Bu2PhP=O (XXI), ClC6H4P(=O)Et2
(XXII),
HOC6H4P(=O)Et2
(XXIII),
forming
complexes in situ (molar ratio complex : additive =
The rate of a reaction depends on the applied
catalyst. It may be that the reduction reaction proceeds
through the formation π-allyl complex of platinum
whose formation is favored by the existence of ligand-
acceptors [4].We quantitatively characterized the
increased role of reduction reaction depending on X by
the molar ratio of product of addition and reduction
ADD/RED. The following sequence was found:
PhO < MeCOO < CH2=C(Me)COO < CF3COO <
C3F7COO < Cl.
1:2).
Content of the adduct in the mixture formed after
the reaction of hydrosilylation of allyl phenyl ether
with triethoxysilane in the presence of the studied
catalysts did not exceed 14.4% (IX + XIX), and in
some cases along with the main product PhO(CH2)3SiX3
(XXIV) formed hydrogenated compound PhO·
(CH2)3SiHX2 (XXV), as is characteristic of nickel
catalysts.
PhOCH2CH=CH2 + HSiY3
→ PhO(CH2)3SiY3 + PhO (CH2)3SiHY2.
(6)
This series coincides with the series of increase in
the acidity of the residue X. Perhaps the suppression of
formation of π-allylic complexes is due to the positive
effects of amines [5] and amides [6] on the yield of the
addition product at the hydrosilylation of allyl chloride
in the presence of platinum catalysts. On the contrary,
yield of γ-chloropropyltrichlorosilane at the hydro-
silylation of allyl chloride with trichlorosilane using as
a catalyst a solution of H2PtCl6 in allyl chloride is
reduced by 15% compared to the Speier catalyst,
probably due to the partial formation of π-allyl
complexes. In the hydrosilylation of allyl chloride with
triethoxysilane the ratio ADD/RED is particularly low
(0.18). At the use of hydrochlorosilane instead of
triethoxysilane the ADD/RED increases, and in the
presence of the Speier catalyst with vinyltriethoxy-
silane it reaches 13.46. It should be noted that in the
hydrosilylation of allyl acetate with triethoxysilane
even in the presence of the Speier catalyst with
vinyltriethoxysilane it was impossible to eliminate
completely the reduction, but only possible to increase
the ADD/RED ratio.
XXIV
XXV
Similar data on the hydrosilylation of hexene with
methyldichlorosilane were obtained by V.O. Reikhsfel’d
and N.K. Skvortsov [8].
The content of the product of reduction C6H5OSiY3
(XXVI) reached maximum 60% (Y = OEt) and 13.8%
(Y = Cl), but the second product, namely propylene
[Eq. (2)], and the products of hydrosilylation of the
latter were not found. Perhaps, propylene underwent
polymerization: in the synthesis always a dark-colored
solid precipitate is formed, in some experiments in the
GLC was detected a peak between the peaks of
phenyltriethoxysilane and γ-phenoxypropyltriethoxy-
silane similar to that of propylene tetramer, that
disappears at longer synthesis. The following sequence
of activity in the reaction of reduction [Eq. (2)] is
obtained (in parentheses the content of the reduction
product in the reaction mixture, %): XVI + XXIII
(60.6) > XVI + XXI (56.4) > X + XIX (55.3) > X +
XVII (46.6) > XVI + XXII (46.2) > XVI + XIX
(40.7) > XI + XIX (39.8) > IX + XIX (35.8) > XV +
XIX (29.0)
Nickel is known to form π-allyl complexes easier
than platinum [7]. As catalysts for hydrosilylation of
allyl phenyl ether with hydrosilanes we examined the
following bivalent nickel complexes: NiCl2·(PPh3)2 (I),
NiCl2·[P(C6H11)3]2 (II), NiBr2·(PBu3)2 (III), NiBr2·
(PPh3)2 (IV); zero-valence nickel complexes: Ni(CO)2·
(PPh3)2 (V), Ni(C6H5CH=CHC6H5)·(PPh3)2 (VI),
The strongest reductive properties display nickel
complexes containing as ligands duroquinone (VIII–
X) and tetracyclone (XI) with phosphine oxides.
1
DQ = duroquinone.
2
C10H12 is biscyclopentadiene.
3
TCC is tetracyclone.
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EFFECT OF CATALYSTS ON THE REACTION OF ALLYL ESTERS
731
Table 2. Reaction of allyl phenyl ether with hydrosilanes in the presence of nickel catalysts
PhOCH2CH=CH2 + HSiY3 → PhO (CH2)3 SiY3 + PhO (CH2)3 SiHY2 + PhOCH=CHCH3
The composition of the
mixture, %
XXIV XXV XXVI
Molar ratio
catalyst:allyl
phenyl ether
propylphenyl
ether:allyl
phenyl ether
Conditions of reaction
Catalyst
Y
Note
method temperature, °С
time, h
7
10–3
OС2H5
2
125
0
0
0
Solvent
CH2Cl2
I
10–2
10–3
10–3
10–3
10–3
10–3
10–2
10–2
10–3
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
Сl
2
2
2
2
1
1
1
1
2
1
1
1
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
125
140
140
140
20
20
20
14
20
20
25
25
17
24
25
20
14
25
70
26
26
12
25
12
25
26
24
24
24
25
25
25
25
25
25
25
25
25
24
25
25
25
25
25
25
25
25
25
25
25
0
0
0
0
0
0
0
0
0
0
0
8.3
29
18
0
15/32
21/15
8.9/30
27/14
I + PPh3
I + CuCl
II
0
0
0
0
0
0
0
21.1
18
0
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
Cl
115
145
125
125
135
150
115
110
110
115
4.7
0
5.6/14.5
19/10
Precipitate
III
IV
Traces
8.0
0
0
12.0
0
14.3
14.4
0
10.2
5.6
0
V
0
0
0
1.5
0
11
0
0
0
0.08/1
1/16
3.8/9.3
0
VI
VII
VIII
VIII + XIX
IX
0.5×10–2
10–3
60.3
16.7
11.1
35.8
2.5
55.3
46.6
0
39.8
0
0
0
Precipitate
Precipitate
IX + XVII
IX + XIX
X
X + XIX
X + XVII
XI
XI + XIX
XII
XIII
XIV
10–3
0.8
0.8
0
0
3/9.2
10–3
10–3
125
125
125
115
125
125
125
125
125
125
125
125
125
125
125
125
110
125
125
125
125
125
125
125
125
125
125
125
0
0/3.2
Precipitate
Precipitate
0
0
10–3
10–3
10–3
10–3
6.6
0
0
0
0.8
0
0
0
0
0
Precipitate
Precipitate
0
0
X + XVII
XV + XIX
7.1
78.2
65.5
19.2
35.6
20.2
35.8
10.7
50.9
12.4
69.0
39.6
32.5
11.2
8.5
0
0
16.4
2.4
1×10–3
0.5×10–2
1×10–2
1×10–2
1×10–2
1×10–2
1×10–2
1×10–2
Cl
1.2
1.5
19.4
7.9
10.3
9.9
3.8
1.5
0.23/0.3
Cl
XV + XX
Cl
12.2
13.8
9.9
5.0/3.0
3.1/2.0
6.0/6.6
3.9/3.9
XV + XXI
XV + XXII
XV + XXIII
XVI + XVII
XVI + XIX
Cl
Cl
Cl
7.3
Cl
10.5
2.2
20.2/21.4
20.0/21.4
11.1/40.7
5.8/1.6
Cl
Cl
1.2
XVI + XXI
XVI + XXII
XVI + XXIII
XV + XIX
1×10–2
1×10–2
1×10–2
1×10–2
1×10–2
1×10–2
1×10–2
1×10–2
1×10–2
1×10–2
1×10–2
Cl
3.3
8.7
8.3
2.5
0.7
0
6.2
0.7
1.5
0.4
1.2
3.9
Cl
5.1
3.3/3.2
Gas
Gas
Precipitate
Precipitate
Cl
9.7
9.3/6.0
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
OC2H5
29
1.3/5.1
XV + XX
18.8
15.3/5.4
XVI + XVII
XVI + XIX
XVI + XX
10.7
8.5
5.7
10.7
7.8
40.7
11.8
56.4
46.2
60.6
1.3/1.6
15.3/15.4
0.9/4.4
10.2/5.4
0.8/4.2
Precipitate
XVI + XXI
XVI + XXII
XVI + XXIII
Precipitate
Precipitate
Precipitate
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732
BELYAKOVA et al.
Table 3. Hydrosilylation of olefins with hydrochlorosilanes in the presence of nickel catalysts
RCH=CH2 + MenSiHCl3–n → RCH2CH2SiMenCl3–n + RCH2CH2SiMenHCl2–n
The composition of
Conditions of reaction
Reaction (3)
contribution, %
the mixture, %
Catalyst
R
n
method
time, h
25
24
25
20
25
24
25
8
temperature, °С
XXIV
XXV
C6H13
C5H11
C5H11
C5H11
C5H11
C5H11
C5H11
C5H11
C5H11
C6H13
C5H11
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
1
1
2
2
2
1
1
135
130
125
135
125
125
125
125
125
130
130
8.0
12.5
21.0
3.6
0
4.0
14.3
0
0
20
0
30
0
0
0
0
0
II
V
VI
VII
0
0
XII
17.5
8.0
3.6
0
XIII
XIV
XV + XIX
79.5
70.3
77.8
94.3
0
0
0
0
5
22
22
0
0
Like with trichlorosilane, with triethoxysilane allyl–
propenyl isomerization often occurred [Eq. (3)]. The
ratio of the formed allyl propenyl ether to the initial
allyl phenyl ether reaches even 3:1.
meter, column 4×2000 mm, stationary phase Chro-
maton N-AW + 15% PMS 20000. The flow rate of
carrier gas (helium) 60 ml min–1. The temperature of
the evaporator 550°C, of oven from 50 to 250°C, the
programmed heating rate 20 deg min–1. The substances
obtained were identified by GLC by comparison with
known samples.
Hydrosilylation in the presence of platinum
catalysts. Speier catalyst (0.02 ml) + 0.02 ml of an
additive was heated at 50°C for 0.5 h, then 0.1 mol of
hydrosilane was added and over 20–25 min 0.1 mol of
allyl ester (or allyl chloride) was added at 50–65°C
(without heating). Then heating was continued for
some time (method 1). Method 2: the order of addition
is reversed. Method 3: the components were added as a
mixture.
Hydrosolylation in the presence of nickel
catalysts. To the reaction vessel flushed with argon
were placed 0.01 mol of allyl phenyl ether, 0.015 mol
of hydrosilane and the catalyst. The mixture of
reactants with the catalyst was refluxed in the flask
(method 1). The ampoule with the components was
sealed and heated at a certain temperature (method 2).
The degree of isomerization of allyl phenyl ether
depends on the heating duration, the nature of the
catalyst, and the concentration of the latter. Adding of
copper(I) chloride and triphenylphosphine, two moles
each relatively to the catalyst, increases dramatically
the isomerization. It is also seen from the data in Table 2
that in the presence of triethoxysilane the contribution
of isomerization is greater than in the presence of
methyldichlorosilane and trichlorosilane. By special
experiment we showed that in the absence of hydro-
silane the isomerization of allyl phenyl ether under the
same conditions does not occur. The isomerization
occurs more often in the cases where no other reaction
proceeds, but this is not the rule. In the presence of the
other studied complexes the original substance
returned unreacted.
The hydrosilylation of simple olefins in the
presence of nickel catalysts proceeds easier and less
complicated by the formation of by-products; the yield
of the main compound reached 94.3% (Table 3).
ACKNOWLEDGMENTS
RCH=CH2 + MenSiHCl3–n → RCH2CH2SiMenCl3–n
+ RCH2CH2SiMenHCl2–n
.
The nickel complexes have been provided by
L.S. Isaeva (INEOS, Russian Academy of Sciences),
phosphine oxides by N.K. Skvortsov (St. Petersburg
State Technological Institute) to whom the authors
express their gratitude.
EXPERIMENTAL
Products of reactions were analyzed on an LKhM-
72 chromatograph equipped with a detector katharo-
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 80 No. 4 2010

EFFECT OF CATALYSTS ON THE REACTION OF ALLYL ESTERS
733
4. Khenritsi-Olive, G. and Olive, S., Koordinatsiya i kataliz
(Coordination and Catalysis), Moscow: Mir. 1980, p. 203.
5. Hu Chunye, Yang Ponghua, and Jiang Yingyan, J., Mol.
Catal., 1998, vol. 2, no. 1, pp. 38–43; Ref. Zh. Khim.,
1990, 10 B 4106.
REFERENCES
1. Pomerantseva, M.G., Belyakova, Z.V., Golubtsov, S.A.,
Zubkov, V.I., Ainshtein, A.A., and Baranova, G.G., Zh.
Obshch. Khim., 1972, vol. 42, no. 4, pp. 862–866.
6. Japan Patent no. 63179883, 1988; Ref. Zh. Khim., 1990,
5 N 181P.
2. Belyakova, Z.V., Pomerantseva, M.G., and Golub-
tsov, S.A., Zh. Obshch. Khim., 1977, vol. 44, no. 8,
pp. 1780–1784.
7. Wilkinson, G., Comperative Organometallic Chemistry,
New York: Pergamon Press, 1986, vol. 6, p.160.
8. Moldavskaya, N.A., Skvortsov, N.K., Voloshina, N.F.,
and Reikhsfel’d, V.O., Zh. Obshch. Khim., 1981, vol. 51,
no. 7, pp. 1621–1624.
3. Belyakova, Z.V., Pomerantseva, M.G., Bykovchen-
ko, V.G., and Chernyshev, E.A., Zh. Obshch. Khim.,
1976, vol. 46, no. 5, pp. 1034–1040.
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