New polyunsaturated organosilicon dendrimers based on 1,1-diethynyl-and 1-vinyl-1-ethynylsilacycloalkanes

Article abstract of DOI:10.1134/S1070363206080172

1,1-Dichloro-and 1-vinyl-1-chlorosilacyclanes were prepared by reactions of tetrachlorosilane or vinyltrichlorosilane with magnesium and 1,4-dibromobutane or 1,5-dibromopentane. The reactions of the products obtained with ethynylmagnesium bromide or bis(bromomagnesio)acetylene yield the corresponding ethynylsilacyclanes. Condensation of 1,1-diethynylsilacyclanes or bis(ethynylsilacyclopentyl)ethyne with an equimolar amount of ethylmagnesium bromide and methylbis(trimethylsilylethynyl)fluorosilane gave the corresponding highly unsaturated mono-and binuclear first-generation dendrimers with the cores formed by the silicon atoms incorporated in silacycloalkane fragments. The ¹H, ¹³C, and ²⁹Si NMR spectra of all the compounds obtained were studied. The key parameters and the chemical graph of the new dendrimers are presented. Nauka/Interperiodica 2006.

Full text of DOI:10.1134/S1070363206080172

ISSN 1070-3632, Russian Journal of General Chemistry, 2006, Vol. 76, No. 8, pp. 1261 1265.
Pleiades Publishing, Inc., 2006.
Original Russian Text L.V. Zhilitskaya, E.E. Istomina, O.G. Yarosh, M.G. Voronkov, 2006, published in Zhurnal Obshchei Khimii, 2006, Vol. 76, No. 8,
pp. 1315 1319.
New Polyunsaturated Organosilicon Dendrimers
Based on 1,1-Diethynyl- and 1-Vinyl-1-ethynylsilacycloalkanes
L. V. Zhilitskaya, E. E. Istomina, O. G. Yarosh , and M. G. Voronkov
Favorskii Irkutsk Institute of Chemistry, Siberian Division, Russian Academy of Sciences,
ul. Favorskogo 1, Irkutsk, 664033 Russia
e-mail: voronkov@irioch.irk.ru
Received October 27, 2005
Abstract 1,1-Dichloro- and 1-vinyl-1-chlorosilacyclanes were prepared by reactions of tetrachlorosilane
or vinyltrichlorosilane with magnesium and 1,4-dibromobutane or 1,5-dibromopentane. The reactions of the
products obtained with ethynylmagnesium bromide or bis(bromomagnesio)acetylene yield the corresponding
ethynylsilacyclanes. Condensation of 1,1-diethynylsilacyclanes or bis(ethynylsilacyclopentyl)ethyne with an
equimolar amount of ethylmagnesium bromide and methylbis(trimethylsilylethynyl)fluorosilane gave the
corresponding highly unsaturated mono- and binuclear first-generation dendrimers with the cores formed by
1
the silicon atoms incorporated in silacycloalkane fragments. The H, 13C, and 29Si NMR spectra of all the
compounds obtained were studied. The key parameters and the chemical graph of the new dendrimers are
presented.
DOI: 10.1134/S1070363206080172
We have described previously 1-methyl-1-ethynyl-
silacyclobutane and -pentane, and also 1,1-diethynyl-
silacyclobutane and -pentane [1 3]. Proceeding with
these studies, we have prepared new representatives of
ethynylsilacycloalkanes. By the reaction of 1,1-dichlo-
rosilacyclohexane or 1-vinyl-1-ethynylsilacyclopen-
tane (-hexane) with ethynylmagnesium bromide in
THF, we have prepared 1,1-diethynylsilacyclohexane
I, 1-vinyl-1-ethynylsilacyclopentane II, and 1-vinyl-1-
ethynylsilacyclohexane III in 76, 66, and 93% yields,
respectively.
+ 2MgBrC CH
SiCl2
Si(C CH)2
I
(CH2)nSi(CH=CH2)Cl + BrMgC CH
(CH2)nSi(CH=CH2)C CH,
II, III
n = 4 (II), 5 (III).
The reaction of 1-vinyl-1-chlorosilacyclopentane
with bis(bromomagnesio)acetylene in THF gave bis-
(vinylsilacyclopentyl)ethyne IV in 35% yield.
Combined reaction of 1,1-dichlorosilacyclopentane
with bis(bromomagnesio)acetylene and ethynylmag-
nesium bromide in 2:1:2 molar ratio in THF gave
bis(ethynylsilacyclopentyl)ethyne V in 14% yield.
CH=CH2
+ BrMgC CMgBr
Si
2
+ BrMgC CMgBr + 2HC CMgBr
SiCl2
2
Cl
Si CH=CH2
CH2=CH Si C C
Si
HC C
C C Si C CH
V
IV
Deceased.
Ethynylsilacycloalkanes I IV are colorless liquids
1261

1262
ZHILITSKAYA et al.
with the characteristic odor of ethynylsilanes, which
can be distilled in a vacuum. Bis(ethynylsilacyclo-
pentyl)ethyne V is a crystalline substance, mp 125 C.
reactants at a temperature below 50 C gave 1,1-bis-
[methylbis(trimethylsilylethynyl)silylethynyl]sila-
cyclopentane IX and -hexane X.
The starting 1,1-dichlorosilacyclohexane VI was
prepared by the reaction of tetrachlorosilane with
magnesium and 1,5-dibromopentane in anhydrous
ether in 62% yield.
(CH2)nSi(C CH)2 + 2EtMgBr + 2(Me3SiC C)2SiMeF
Me
C C Si1 Me
Me
C C Si2 Me
Me
Br(CH2)5Br + SiCl4 + 2Mg
SiCl2
VI
C C Si Me
Me
(CH2)nSi3
1-Vinyl-1-chlorosilacyclopentane VII and -hexane
VIII were synthesized by the reaction of vinyltrichlo-
rosilane with magnesium and 1,4-dibromobutane or
1,5-dibromopentane in 30 and 32% yields, respec-
tively.
Me
C C Si Me
Me
C C Si Me
Me
CH2=CHSiCl3 + 2Mg + Br(CH2)nBr
(CH2)nSi(CH=CH2)Cl,
C C Si Me
Me
IX, X
VII, VIII
n = 4 (VII), 5 (VIII).
n = 4 (IX), 5 (X).
The yields and physical constants of I VIII are
The synthesized compounds IX and X are the first-
generation (G1) dendrimers. Their center is the silicon
atom simultaneously incorporated in a silacyclopen-
tane or silacyclohexane ring. This atom is the zero
branching point.
listed in Table 1. The structure of ethynylsilacycloal-
1
kanes I V was confirmed by H, 13C, and 29Si NMR
data (Table 2).
The presence of ethynyl groups containing a labile
hydrogen atom in compounds I V allows them to be
involved in various condensations. By this pathway
we prepared the first organosilicon acetylenic den-
drimers with the cyclic core. In particular, the re-
action of 1,1-diethynylsilacyclopentane or -hexane
with an equimolar amount of ethylmagnesium bro-
mide and methylbis(trimethylsilylethynyl)fluorosilane
in THF under at high dilution and slow mixing of the
The product of the reaction of bis(ethynylsilacyclo-
pentyl)ethyne with ethylmagnesium bromide and
methylbis(trimethylsilylethynyl)fluorosilane under the
similar conditions is the binuclear cyclic dendrimer
(G1) containing an acetylene bridge between two
silicon atoms in silacyclopentane rings, bis{1-[me-
thylbis(trimethylsilylethynyl)silylethynyl]silacyclo-
pent-1-yl}ethyne XI.
HC C
Si C C Si C CH + 2EtMgBr + 2(Me3SiC C)2SiMeF
Me
Me
C C Si1 Me
Me
Me Si C C
Me
Me
Me Si C C
Me
3
Si C C Si C C Si2 Me
Me Si C C
Me
C C Si Me
Me
XI
Dendrimer IX is a colorless viscous liquid which
can be distilled in a vacuum, and compounds X and
XI are crystalline substances. All these compounds
are soluble in hydrocarbons, ether, THF, and chloro-
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 76 No. 8 2006

NEW POLYUNSATURATED ORGANOSILICON DENDRIMERS
Table 1. Constants of compounds I XI
1263
Found, %
H
Calculated, %
H Si
bp,
or mp,
(p, mm Hg)
C
Comp. Yield,
C
d240
n2D0
Formula
no.
%
C
Si
C
I
II
76
66
93
45
14
62
30
32
25
45
20
69 (12) 0.9383 1.4840 72.42
60 (25) 0.8784 1.4780 71.32
70 (12) 0.9008 1.4780 70.55
8.25
8.44
9.39
9.22
8.26
18.35
30.58
17.62
21.89
26.23
C9H12Si
C8H12Si
C9H14Si
72.90
70.58
71.92
68.21
69.34
8.16
8.56
9.39
9.00
7.48
18.94
30.63
18.68
22.79
27.08
III
IV
Va
VI
VII
VIII
IX
X
100 (1)
125
0.9684 1.4825 69.11
68.56
C14H22Si2
C14H18Si2
C7H13ClSi
C6H11ClSi
C7H13ClSi
C30H50Si7
C31H52Si7
C36H58Si8
62 (12) 1.1634 1.4700
61 (22) 1.0774 1.4792
60 (4)
105 (2)
86
1.0791 1.4840
58.13
59.92
58.90
9.66
8.43
9.32
31.13
31.64
32.04
59.40
59.95
60.46
8.32
8.69
8.12
32.64
31.23
31.37
XI
59
a
m/e (I , %) 242 (13).
rel
Table 2. 1H, 13C, and 29Si NMR spectral parameters of ethynylsilacycloalkanes I V
1H NMR spectrum, , ppm (J, Hz)
Comp.
no.
2
5
3
2
6
3
4
4
SiCH=
=CH2
5.98
CH
Si
Si
5
I
2.47
0.85 (H2, H6), 1.42 (H4),
1.73 (H3, H5)
II
6.12 (Jtrans 18.42, Jcis 5.26)
2.47 0.67 (H2, H5), 1.45 (H3, H4)
2.42
III 6.09, 6.07 (Jtrans 17.24, Jcis 6.72) 5.91
0.75 (H2, H6), 1.42 (H4),
1.71 (H3, H5)
IV 6.19, 6.14 (Jtrans 20.18, Jcis 14.69, 6.01,
0.62 (H2, H5), 0.64 (H2, H5),
1.56 (H3, H4), 1.64 (H3, H4)
Jgem 3.51)
5.97,
5.84,
5.78
V
2.52 0.53 (H2, H5), 1.60 (H3, H4)
13C NMR spectrum, C, ppm
29Si MMR
spectrum,
Si, ppm
Comp.
no.
2
3
3
2
6
4
SiCH= =CH2
SiC
CH
Si
Si
4
5
5
I
84.55
94.86
13.10 (C2, C6), 23.27 (C3, C5),
29.94 (C4)
42.32
10.02
26.82
II
III
134.58 133.83 86.69
134.55 133.92 86.80
137.39 132.63
95.53 12.51 (C2, C5), 27.01
(C3, C4)
94.61
12.33 (C2, C6), 23.93 (C3, C5),
29.47 (C4)
IV
V
12.93 (C2, C5), 26.06 (C3, C4)
13.15
28.37
84.76, 95.53 13.60 (C2, C5), 26.56
110.58
(C3, C4)
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 76 No. 8 2006

1264
ZHILITSKAYA et al.
Table 3. 1H, 13C, and 29Si NMR spectral parameters of dendrimers IX XI
1H NMR spectrum, , ppm (J, Hz)
Comp.
no.
2
3
2
6
3
4
Si1Me3=
Si2Me
4
Si
Si
5
5
IX
X
XI
0.16
0.18
0.17
0.26
0.46
0.43
0.61 (H2, H5), 1.03 (H3, H4)
1.25 (H2, H5), 1.65 (H3, H4)
0.87 (H2, H6), 1.39 (H4), 1.74 (H3, H5)
29Si MMR spectrum, Si, ppm
13C NMR spectrum, C, ppm
Comp.
no.
2
3
2
3
4
Si1Me3 Si2Me
SiC
Si1
Si2
Si3
4
Si
Si
5
6
5
IX
X
0.25
0.43
0.22
1.84
1.19
1.3
6.96 (C2, C5),
8.14 (C3, C4)
106.70, 115.53,
108.96, 108.90
105.84, 116.71,
109.05, 109.69
116.42, 106.05
18.40
17.36
17.92
70.0
69.45
70.26
38.24
37.55
38.55
XI
13.74 (C2, C5),
29.70 (C3, C4)
form and are stable in storage. The yields of IX XI,
merous acetylenic bonds in dendrimers IX XI offers
unlimited opportunities for their further transforma-
tions into still more complex dendrimeric nanosized
structures.
1
their physical constants, and H, 13C, and 29Si data
are listed in Tables 1 and 3.
These compounds show promise as mesoporous
materials for membranes [5]. The presence of nu-
We have calculated some key parameters for
didendrones IX and X having a regular structure [6].
Generation number, G = 1; branching index or
number of dendrones growing from the core, NC =
2; branching index of units, i.e., the number of
branches formed by each repeating unit, NB = 2.
dendrone 1
Me
Si
Si
Si
Me
Me
Me
1Si
C
C
The degree of polymerization or the number of
repeating units was calculated by the formula
C
C
Me
Me
Me
NBG+1
NB
1
C
P = NC
.
1
C
branching
points
0 Si
terminal
groups
Number of terminal groups: Z = NCNGB = 4.
Me
C
Me
The chemical graph of didendrone IX is shown in
the figure. The chemical graph of dendrimer X is
similar to that of IX.
C
C
core
Me
C
1Si
C
C
Me
Me
Me
EXPERIMENTAL
Me
Si
The NMR spectra were taken on a Bruker DRX-
400 spectrometer (400 MHz) from 15% CDCl3 solu-
tions against internal HMDS.
dendrone 2
Chemical graph of a macromolecule of didendrone IX.
All the solvents used were thoroughly dried.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 76 No. 8 2006

NEW POLYUNSATURATED ORGANOSILICON DENDRIMERS
1265
1,1-Dichlorosilacyclopentane and methylbis-
(trimethylsilylethynyl)silane were prepared by the
previously described procedure [3, 7].
of 8.5 g of methylbis(trimethylsilylethynyl)fluoro-
silane in 50 ml of ether was added dropwise with stir-
ring. The resulting mixture was heated for 30 min at
50 C and treated with water, 5% NH4Br, and 5% HCl,
after which it was worked up as described above.
Crystallization from hexane gave 5.58 g (45%) of X.
1,1-Diethynylsilacyclohexane I. To a solution of
10.14 g of 1,1-dichlorosilacyclohexane in 50 ml of
anhydrous ether, a solution of HC CMgBr prepared
from 2.9 g of Mg, 13 g of ethyl bromide, and ace-
tylene in 100 ml of freshly distilled THF was added
with stirring. After heating at 50 C for 30 min, the
mixture was treated with water and 5% HCl. The
aqueous layer was separated on a separatory funnel
and extracted with ether (3 30 ml). The combined
ether extracts were dried over calcined CaCl2. The
drying agent was filtered off and washed with
anhydrous ether (2 30 ml). The solvents were
removed in a water-jet-pump vacuum; vacuum distil-
lation of the residue gave 6.73 g (76%) of I.
Compounds IX and XI were prepared similarly.
ACKNOWLEDGMENTS
The study was financially supported by the Grant
Council of the President of the Russian Federation
(grant no. NSh-4575-2006.3).
REFERENCES
1. Voronkov, M.G., Yarosh, O.G., Ivanova, Z.G., Ro-
man, V.K., and Albanov, A.I., Izv. Akad. Nauk SSSR,
Ser. Khim., 1987, no. 6, p. 1403.
Compounds II V were prepared similarly.
1,1-Dichlorosilacyclohexane VI. To 4.8 g of Mg
in 300 ml of anhydrous ether, 17 g of tetrachlorosilane
was added with stirring. After that, 23 g of 1,5-di-
bromopentane was added dropwise. The reaction
mixture was refluxed with stirring for 4 h. After
cooling, the precipitate was filtered off and washed
with 300 ml of anhydrous ether. The solvent was
removed, and the residue was distilled in a vacuum
to give 10.49 g (62.1%) of compound VI.
2. Voronkov, M.G., Yarosh, O.G., Roman, V.K., and
Albanov, A.I., Metalloorg. Khim., 1990, vol. 3, no. 6,
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Compounds VII and VIII were prepared similarly.
2001, no. 16, p. 1442.
1,1-Bis[methylbis(trimethylsilylethynyl)silyl-
ethynyl]silacyclohexane X. A solution of bis(bro-
momagnesioethynyl)silacyclohexane prepared from
0.9 g of Mg, 5 g of ethyl bromide, and 10.4 g of I in
50 ml of THF was added dropwise with stirring to
50 ml of freshly distilled THF. After that, a solution
6. Semchikov, Yu.D., Soros. Obraz. Zh., 1998, no. 12,
p. 45.
7. Yarosh, O.G., Zhilitskaya, L.V., Burnashova, T.D., and
Voronkov, M.G., Metalloorg. Khim., 1989, vol. 2,
no. 3, p. 515.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 76 No. 8 2006