Synthesis and properties of polysilanes with tetrathiafulvalene as pendant group

Article abstract of DOI:10.1039/b713819a

Two polysilanes with tetrathiafulvalene (TTF) as pendant groups were synthesized by reaction of 2-cyanoethyl substituted TTF 1 with (chloromethylphenyl)dimethyl(phenyl)polysilane, or reaction of 4-vinylphenyl-TTF 2 with poly[methylsilane-co-methyl(phenyl)

Full text of DOI:10.1039/b713819a

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Synthesis and properties of polysilanes with tetrathiafulvalene as pendant
group
Yibo Liu,a Chengyun Wang,*a Meijiang Li,b Guoqiao Laib and Yongjia Shen*a
Received (in Durham, UK) 11th September 2007, Accepted 19th November 2007
First published as an Advance Article on the web 4th December 2007
DOI: 10.1039/b713819a
Two polysilanes with tetrathiafulvalene (TTF) as pendant groups were synthesized by reaction of
2-cyanoethyl substituted TTF 1 with (chloromethylphenyl)dimethyl(phenyl)polysilane, or reaction
of 4-vinylphenyl-TTF 2 with poly[methylsilane-co-methyl(phenyl)silane]. The structures and
1
properties of TTF-polysilanes and their intermediates were characterized by H NMR, mass,
GPC, UV/Vis, IR and cyclic voltammetry (CV). The results of UV/Vis and CV of these
polysilanes indicated interaction between the TTF moieties and s-electron delocalized Si–Si chain
in the ground states. These polysilanes doped by I2 exhibited high conductivities (10À2 S cmÀ1).
classical synthetic reaction of cyanoethyl-TTF and an active
Introduction
halide, i.e., deprotection of the 2-cyanoethyl group in TTF 1
Polysilanes comprising Si–Si bonds have attracted much at-
with the aid of CsOH followed by the reaction with (chloro-
tention for their potential applications as functional poly-
methylphenyl)dimethyl(phenyl)polysilane afforded polymer
mers,1 such as photoconducting materials,2 conductors and
P1. The second one is the addition reaction of 4-vinylphe-
semiconductors,3,4 photoresists,5 Si–C ceramic precursors6
nyl-TTF 2 to poly[methylsilane-co-methylphenylsilane] in the
and NLO materials.7 Some of their intriguing electrical pro
presence of a catalytic amount of hexachloroplatinic acid
perties are related to the specific s-electron delocalization,
giving polymer 2. TTF 1 was synthesized according to a
literature procedure.13 The key intermediate TTF 2 and 3
which endows polysilanes with a directional conductivity that
is strongest along the axis of the chain. Meanwhile, tetrathia-
were synthesized by the reaction of TTF 1 and 4-(bromo-
fulvalene (TTF) and its derivatives are also of interest because
methyl)-1-vinylbenzene or benzyl bromide in the presence of
they have large electron donating properties and can form
CsOHÁH2O. Poly(hydrosilane)copolymer (PHMS), Methyl-
highly conducting charge-transfer complexes.8 Especially,
phenylpolysilane (PMPS) and (chloromethylphenyl)dimethyl-
crystals of TTF CT-complexes have metallic conductivity
phenylpolysilane (CMPMPS) were synthesized according to
the reported procedures.14–16
1
The H NMR spectra of polymers P1 and P2 are shown in
because of the regular formation of segregated stacks of
donors and acceptors and a certain degree of charge transfer
between the stacks. Despite the inherent electronic advantages,
Fig. 2. In polymer P1, the methyl protons of the Si–CH3
crystals of TTF CT-complexes tend to be brittle and unpro-
groups appeared as a broad peak at d 0.01–0.46 ppm, those of
the phenyl groups gave a broad peak at d 7.40–6.97 ppm, and
the methylene protons (PhCH2–TTF and PhCH2Cl) in poly-
cessable. The polymers of TTF can overcome this problem for
their good processability, however, they possess lower con-
ductivity than that of crystalline TTF CT-complexes. There
mer P1 gave a peak at d 4.57. S–CH2–, –CH2– and –CH3
protons of TTF groups in polymer P1 gave broad peaks at d
2.79–2.98, 1.20–2.03 and 0.89–1.02, respectively. The numbers
have been several attempts to integrate TTF moieties into
some polymers in recent decades,9–12 and it is a potential
direction in conducting polymers.
in Fig. 2 denote the integrated intensities for –CH3 and Ph
In this paper, we report two polysilanes with TTF moiety as
protons in polymers P1 and P2. These two peaks were chosen
pendant group (Fig. 1). Such polymers would possess an
for the integration calculation. On the other hand, the
advantage of both conjugated polymer chain and electron-
donating side chain.
Results and discussion
Synthesis
Two different synthetic routes lead to polysilanes with TTF
moieties as pendant groups (Scheme 1). The first one is a
a Laboratory of Advanced Materials and Institute of Fine Chemicals,
East China University of Science & Technology, Shanghai 200237,
P. R. China. E-mail: yjshen@ecust.edu.cn, cywang@ecust.edu.cn
b Key Lab of Organosilicon Chemistry and Material Technology of
Ministry of Education, Hangzhou Normal University, Hangzhou
310012, P. R. China
Fig. 1
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Scheme 1
following moieties were chosen as calculated models for poly-
mers P1 and P2.
As an example, the calculation of TTF content in the
polymer P1 is given as:
TTF content in polymer P1 = (1.76/6)M1/[(1.76/6)
M1 + (8.68/5)M2] Â 100% = 42.6%
The chemical shifts of the TTF moiety in polymer P2 were
similar to those of polymer P1. The TTF content in polymer
1
P2 was calculated to be 51.7% based on H NMR.
GPC analysis of polymer P1 showed Mn = 10 238, which
corresponds to a 45.1% content of TTF segments. The GPC
analysis of polymer P2 showed Mn = 7253, corresponding to
a 56.6% content of TTF segments.
The elemental analyses data of polymers P1 and P2 are also
listed in Table 1, the TTF content based on elemental analysis
were 40.66% and 55.13%, respectively, which were close to the
1
values based on H-NMR and GPC.
Thermogravimetric analysis (TGA) was performed in air
within a range of 20–600 1C with a heating rate of 10 1C
minÀ1. The thermal decomposition of the polymers P1 and P2
presented a single stage of decomposition (see Fig. 3). At
almost 35% weight loss was observed upon increasing the
temperature from 200 to 420 1C, which increased to about
50% at 500 1C. The decomposition process was essentially
complete around 700 1C, with 58% weight lost at this stage.
Fig. 2 1H NMR spectra of polymers P1 and P2 in CDCl3. The
numbers denote the integrated intensities for –CH3 protons in the
bis(hexylthio) moieties and Ph protons.
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Table 1 The composition of CMPMPS, PHMS, polymers P1 and P2
Elemental analysis (%)
TTF
contenta (wt%)
TTF content
(wt%)b
TTF contentc
(wt%)
TTF moieties :
Si atoms (mol)a
Polymer
Mn
5631
3147
10 238
7253
Mw/Mn
H
C
S
CMPMPS
PHMS
Polymer P1
Polymer P2
—
—
42.6
51.7
b
—
—
45.1
56.6
c
2.29
1.87
2.20
2.03
—
—
6.25
6.48
—
—
57.39
56.49
—
—
19.75
26.78
—
—
40.66
55.13
—
—
1:6
1:4.2
a
1
Based on H NMR. Based on GPC. Based on elemental analysis.
The IR spectrum displayed the specific absorption band of
that there was no distinct intermolecular interaction between
TTF 3 and PMPS in the mixture.
the Si–CH3 group at 1246 cmÀ1, C–H (phenyl) group at 3066
cmÀ1, the peaks at 540, 510 and 420 cmÀ1 were related to Si–Si
stretching absorption in the polymers P1 and P2. The absorp-
tion band of the Si–H group in the polymer P2 at 2150 cmÀ1
still remained, which indicated that some of the Si–H groups
were retained, because of steric hindrances.3 These residual
Si–H groups are useful for immobilization in the polysilane
and play an important role in the charge-generating process.
The electrochemical properties of TTF 3, polymers P1 and
P2 together with the mixture consisting of TTF 3 and PMPS
with the equivalent molar ratio of TTF moieties : Si atoms
were obtained by cyclic voltammetry. The CV curves of
polymer P1 and TTF 3 are shown in Fig. 5. The voltammetric
data were collected in Table 2.
As shown in Table 2, TTF 3 showed two one-electron
reversible oxidation waves at 0.56 and 0.96 V, respectively,
corresponding to the radical cation TTF+ and dication
TTF2+. The polymers P1 and P2 also showed two reversible
oxidation waves at 0.66, 1.14 V and 0.67 and 1.16 V, respec-
tively. It was clear that the TTF moiety retained its electro-
chemical activity in polymers P1 and P2. Significant
enhancement of the oxidation potentials compared to TTF 3
suggested that though polymers P1 and P2 preserved the
electrochemical character of the TTF moiety, they have higher
oxidation potentials than those of TTF 3, probably indicating
an intramolecular interaction between the Si–Si system and
TTF moiety in the ground state, due to the unique s-electron
delocalization similarly to some D–s-A compounds contain-
ing the TTF unit.8 The CV curve of a mixture consisting of
TTF 3 and PMPS was coincident with that of TTF 3, this
result also indicated that there was no distinct intermolecular
interaction between TTF 3 and PMPS.
UV/Vis spectra and cyclic voltammetry
The UV absorption maxima of the model compound TTF 3,
polymer PMPS, PHMS and polymers P1 and P2 together with
a mixture consisting of TTF 3 and PMPS with the equivalent
molar ratio of TTF moieties : Si atoms in CH2Cl2 are
summarized in Table 2. The absorption curves of the polymer
3, for example, are shown in Fig. 4. Polymer PMPS, PHMS
and TTF 3 showed absorption peaks at 338, 337 and 335 nm,
respectively. The maximum of the absorption curve of poly-
mer P1 was found at 316 nm, which suggests that the absorp-
tion of the polysilane moiety and TTF moiety in polymer P1
were overlapped. Surprisingly it was remarkably blue shifted
compared to those of TTF 3 and PMPS, and it was the same
for polymer P2. These results probably indicated an intramo-
lecular interaction between Si–Si system and TTF moiety due
to the unique s-electron delocalization.8 On the other hand,
the UV/Vis absorption curve of a physical mixture consisting
of TTF 3 and PMPS exhibited neither a new peak nor any
peak shift on the whole wavelength range. It may be concluded
Polysilane comprising Si–Si chain possesses unique s-elec-
tron delocalization, which endowed the polysilane with elec-
tron-accepting properties. The same situation also occurs for
poly(aryleneethynylene) species.17,18 Therefore, as for many
D–s-A compounds containing the TTF unit,8 the bridge
(alkylene and phenyl) between the Si–Si chain and TTF moiety
did not block the interaction between them. Actually, the
results of UV/Vis spectra and cyclic voltammetry of polymers
P2 exhibited that there were intramolecular interactions
Table 2 UV peaks and voltammetric data of polymers P1 and P2,
PMPS, PHMS and TTF 3
Compound
lmax/nm (25 1C) in CH2Cl2
CV (E1/2/V)
PMPS
PHMS
TTF 3
Polymer P1
Polymer P2
Mixturea
a
270, 338
274, 337
263, 335
266, 316
265, 314
262, 270, 336
—
—
0.56, 0.96
0.66, 1.14
0.67, 1.16
0.56, 0.97
Mixture consisting of TTF 3 and PMPS with the equivalent molar
ratio of TTF : Si atoms.
Fig. 3 TGA curves of polymers P1 and P2.
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Fig. 5 CV curves of TTF 3 (10À3 M) and a cast film of polymer P1
in MeCN.
Fig. 4 UV/Vis curves of polymer P1, PMPS and TTF 3 in CH2Cl2.
(5.4 eV) of polysilane is lower than the TTF group (6.7 eV).19
This suggested that charges were first generated from TTF–
iodine complexes, and transferred from the TTF groups to the
Si–Si backbone, finally charge transport occurred by hopping
between the s-electron conjugated Si–Si backbone. Therefore,
the s-electron Si–Si backbone gave the polymer systems
exceptional charge carrying ability and higher conductivity.
Polysilanes with TTF moieties as pendant groups can be
regarded as a new type of polysilane having both charge
generation sites and charge transport sites.
between the Si–Si chain and TTF moieties due to such unique
s-electron delocalization in the Si–Si chain.
Doping and electrical conductivity
Polymer films were prepared by spin-coating their THF solu-
tions onto a ITO glass plate, followed by drying in vacuum at
30 1C for 2 h. The average thickness of the polymer films
determined by a surface stepper was 500–800 mm. After
exposure of the polymers to an iodine atmosphere and re-
moval of the excess iodine in vacuo, the polymer appearance
changed from brown to black, the conductivity was measured
using a four-probe technique with SZ85 apparatus. The con-
tent of iodine was determined by gravimetric analysis. The
conductivity, which depended on the time of exposure and
content of iodine, increased rapidly and reached a plateau
(4 h) as shown in Fig. 6, when the content of iodine in
polymers P1 and P2 were 55 and 61%, respectively.
As shown in Fig. 6, the conductivity reached a plateau and
remained unchanged even when the polymers were exposed in
iodine atmosphere for longer times, which indicated that the
structures of polymers P1 and P2 were stable and Si–Si bonds
were not broken under the oxidative doping conditions. The
fact probably resulted from the carriers in polymers, which
were stabilized by the reversible transfer between the poly-
silane main chain and TTF moieties, even transferring inter-
molecularly through the TTF moieties and iodine.4
The conductivities of polymers P1 and P2, methylpolysilane
and some different TTF polymers doped by I2 were summar-
ized in Table 3.
The conductivity of polymer P2 was higher than that of
polymer P1. Although they were synthesized by two different
routes, their chemical structures were similar to each other.
The conductivities of polymers P1 and P2 with TTF moi-
eties as pendant groups were found to be one to three orders of
magnitude higher than those of non-conjugated TTF polymers
(backbone non-conjugation or pendant groups) and methyl-
polysilanes. Polymers P1 and P2 were oxidized by an equiva-
lent of TCNQ (tetracyanoquinodimethane) using the solution-
phase doping method with acetonitrile as solvent, and their
conductivities were slightly lower than those of polymers P1
and P2 doped by I2. Polymers P1 and P2 possessed higher
conductivities for two reasons. On the one hand, for the
polysilane, s-electrons of the Si–Si backbone can participate
and facilitate the mobilization of the charges along the poly-
silane main chain, thus causing an increase in the conductivity.
On the other hand, TTF and its derivatives would form
charge-transfer (CT) complexes with an electron acceptor,
such as iodine, and in the frame of TTF-based conductors,
such a combination could also contribute to increase the
charges and the dimensionality of the conduction process.
This combination might eventually lead to materials present-
ing hybrid conduction. In general, the ionization potentials
Fig. 6 Time dependence of conductivity of polymers P1 and P2
doped by I2.
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Table 3 The conductivity of iodine-doped polysilanes and some TTF polymers
Polymer
Conductivity (25 1C)/S cmÀ1
Ref.
PMPS
1.3 Â 10À6
This work
4
4
9
10
11
This work
This work
This work
This work
Methylpolysilane (pendant group: dimethylbenzenamine)
Methylpolysilane (pendant group: carbazole)
TTF polymer (pendant group)
TTF polymer (backbone)
1 Â 10À3
1 Â 10À3
5.0 Â 10À7
2.0 Â 10À6 (non-conjugation)
5.5 Â 10ÀÀ12, 1.5 Â 10À2 (conjugation)
1.6 Â 10 (I2)
Polymer P1
Polymer P1
Polymer P2
Polymer P2
7.8 Â 10À3 (TCNQ)
1.9 Â 10À2 (I2)
9.1 Â 10À3 (TCNQ)
The differences could be the result of different content of TTF
moieties in the polymer chain, because the conductivity of
iodine-doped TTF-polysilane was increased with an increase
of TTF content. More TTF moieties in the polymer would
generate more charges, which can transfer to the Si–Si chain
and facilitate the p–p interaction between neighboring TTF
units (intra- and inter-molecular reactions) just as in other
conducting TTF polymers.20
Synthesis of 2-(2-cyanoethylthio)-3-methylthio-6,7-
bis(hexylthio)tetrathiafulvalene (TTF 1)
TTF 1 was synthesized according to the literature.13 Yield:
1
51%. H NMR [400 MHz, CDCl3] d: 3.03 (2H, t, J = 4 Hz,
SCH2CH2CN), 2.83 (4H, t, J = 4 Hz, SCH2–), 2.78 (3H, s,
SCH3), 2.71 (2H, t, J = 4 Hz, SCH2CH2CN), 1.24–1.89 (16H,
m, –CH2–, SCH3), 0.88 (6H, t, J = 6.7 Hz, –CH3). MS (EI,
m/z): 567.02. Anal. Calc. for C22H33NS8: C, 46.52; H, 5.86.
Found: C, 46.51, H, 5.88%.
Some TTF polymers with p-conjugation were reported to
possess similar or higher conductivity, but they were sparingly
soluble and difficult to process. In contrast, polymers P1 and
P2 possess reasonable solubility in THF, CHCl3, toluene
and DMF.
Synthesis of 2-(4-vinylbenzylthio)-3-methylthio-6,7-
bis(hexylthio)tetrathiafulvalene (TTF 2)
To
a solution of 2-(2-cyanoethylthio)-3-methylthio-6,7-
bis(hexylthio)tetrathiafulvalene (1.0 g, 1.76 mmol) in anhy-
drous degassed THF (50 ml) was added a solution of CsOHÁ
H2O (320 mg, 1.9 mmol) in anhydrous degassed MeOH (5
ml) over a period of 30 min. The mixture was stirred for an
additional 30 min, then a solution of 1-(bromomethyl)-4-
vinylbenzene (431 mg, 2.2 mmol) in anhydrous degassed
THF (5 ml) was added. The reaction mixture was stirred
overnight. After removing solvent under reduced pressure
and separation by column chromatography on silica gel with
CH2Cl2–hexane (1 : 6, v/v) as eluent, 2-(4-vinylbenzylthio)-3-
methylthio-6,7-bis(hexylthio)tetrathiafulvalene 2 was obtained
as brown oil, yield: 68% (754 mg).
1H NMR [400 MHz, CDCl3] d: 7.35 (2H, d, J = 8 Hz,
Ar–H), 7.24 (2H, d, J = 8 Hz, Ar–H), 6.69 (H, q, J = 4 Hz,
–CHQ), 5.75 (H, d, J = 8 Hz, QCH–H), 5.26 (H, d, J = 4
Hz, QCH–H), 3.92 (2H, s, SCH2Ph), 2.81 (4H, t, J = 4 Hz,
SCH2–), 2.78 (3H, s, SCH3), 1.24–1.89 (16H, m, –CH2–,
SCH3), 0.88 (6H, t, J = 6.7 Hz, –CH3). 13C NMR [100
MHz, CDCl3]: d 135.0, 134.7, 134.2, 127.8, 127.5, 126.9,
117.2, 113.5, 45.4, 31.3, 29.7, 28.2, 27.3, 19.1, 16.8, 15.0. MS
(EI, m/z): 630.12. Anal. Calc. for C28H38S8: C, 53.29; H, 6.07.
Found: C, 53.30, H, 6.09%.
Conclusions
Novel polysilanes, polymers P1 and P2, with tetrathiafulva-
lene as pendant groups were synthesized by two different
routes. The results of UV/Vis and cyclic voltammetry of the
polymers indicated interaction between the TTF moieties and
Si–Si chain in the ground states. Both polymers exhibited
higher conductivities when doped by I2, and could be regarded
as a new type of polysilane having both charge generation sites
and charge transport sites. The conductivity depended on the
TTF content in the polymers. Polymers P1 and P2 are
promising as good potential conducting materials.
Experimental
All the reagents and solvents were of commercial quality and
were distilled or dried, if necessary, using the standard
procedures.
1H and 13C NMR spectra were recorded on a BRUKER 400
instrument. Mass spectra were measured on a TRACE DSQ
MS. Elemental analyses were performed on a Vario EL III.
Absorption spectra were measured with a Nicolet evolution
300 UV/Vis spectrophotometer. Gel permeation chromatogra-
phy (GPC) was carried out using toluene as a solvent.
Thermogravimetric analysis was performed on a MOM Pau-
lik–Pauli–Erdey derivatograph at 10 1C minÀ1 heating rate in
air. All the electrochemical experiments were performed in
dichloromethane or acetonitrile with n-Bu4NPF6 as the sup-
porting electrolyte, platinum as the working and counter
electrodes, and Ag/AgCl as the reference electrode. The scan
Synthesis of 2-benzylthio-3-methylthio-6,7-
bis(hexylthio)tetrathiafulvalene (TTF 3)
TTF 3 was synthesized with the same procedure as TTF 2,
benzyl bromide was used to replace 1-(bromomethyl)-4-vinyl-
benzene. 2-(benzylthio)-3-methylthio-6,7-bis(hexylthio)tetra-
thiafulvalene (TTF 3) was obtained as red–black solid, yield:
81%.
1H NMR [400 MHz, CDCl3] d: 7.37 (2H, d, J = 8 Hz,
Ar–H), 7.20 (2H, d, J = 8 Hz, Ar–H), 7.18 (2H, d, Ar–H),
3.91 (2H, s, SCH2Ph), 2.82 (4H, t, J = 4 Hz, SCH2–), 2.78
rate was 100 mV sÀ1
.
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(3H, s, SCH3), 1.24–1.88 (16H, m, –CH2–, SCH3), 0.88 (6H, t,
J = 6.7 Hz, –CH3). 13C NMR [100 MHz, CDCl3]: d 135.1,
134.3, 127.8, 127.2, 126.9, 116.8, 117.2, 44.5, 31.3, 29.7, 28.2,
27.3, 19.1, 16.8, 15.0. MS (EI, m/z): 604.11. Anal. Calc. for
C26H36S8: C, 51.61; H, 6.00. Found: C, 51.60, H, 6.02%.
copolymer (1.00 g, 0.47 mmol), and hexachloroplatinic acid
solution in isopropanol (0.1 ml, 0.1 mol lÀ1) dissolved in
freshly dried THF (30 ml) was stirred for 1 h at room
temperature and then refluxed for another 48 h. Then the
reaction mixture was cooled to room temperature and filtered.
The filtrate was concentrated to 10 ml and poured into 200 ml
methanol and the brown solid formed was washed several
times with hexane and dried in vacuum at 30 1C for 5 h, yield:
42% (1.92 g). Mn = 7253. Mw/Mn = 2.03. 1H NMR [400
MHz, CDCl3] d: 7.42–6.98 (SiPh), 4.47–4.61 (PhCH2S),
2.78–2.99 (TTF: SCH2–, SCH3), 0.88–2.14 (SiCH2CH2Ph
and TTF: –CH2–, –CH3). 13C NMR [100 MHz, CDCl3]: d
135.1–126.9 (Ph–C and TTF ring-C), 116.9–117.2 (TTF ring-
C), 46.3, 33.2, 31.4, 29.6, 28.2, 27.5, 19.1, 16.2, 15.1, 12.2, À6.3
(SiCH3). Anal. for polymer P2: C, 6.48, H, 56.49, S, 26.78%.
Synthesis of poly(hydrosilane)copolymer (PHMS)
The poly(hydrosilane)copolymer was obtained by the homo-
geneous reductive coupling between methyldichlorosilane and
methylphenyldichlorosilane.14 The mole ratio of methylphe-
nylsilylene unit to methylhydrosilylene units in the PHMS was
1
about 0.54 : 0.46, based on H NMR spectroscopy, which is
similar to the feeding ratio (1 : 1) of the monomers, yield 11%.
Mn = 3147, Mw/Mn = 1.87.
Synthesis of the methylphenylpolysilane (PMPS)
Methylphenylpolysilane was obtained by Wurtz coupling
reaction,15 yield: 41%, Mn = 25 630, Mw/Mn = 2.36.
Acknowledgements
Synthesis of the chloromethyl methylphenylpolysilane
(CMPMPS)
This work was supported by National Science Foundation of
China (No. 20676036), the Key Project of the Ministry of
Education of China (No. 03053) and the foundation of East
China University of Science & Technology.
The chloromethyl methylphenylpolysilane was synthesized
according to Ban’s report.16 The content of chloromethylene
moieties in the CMPMPS was about 40% of the polysilane
chain, based on 1H NMR, yield: 46%, Mn = 5631, Mw/Mn =
2.29.
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Synthesis of polymer P1
To
a solution of 2-(2-cyanoethylthio)-3-methylthio-6,7-
bis(hexylthio)tetrathiafulvalene (1.62 g, 2.86 mmol) in anhy-
drous degassed CHCl3 (30 ml) was added a solution of CsOHÁ
H2O (480 mg, 2.86 mmol) in anhydrous degassed MeOH (5
ml) over a period of 30 min. The mixture was stirred for an
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(chloromethylphenyl)methylphenylpolysilane (1.0 g, 0.22
mmol) in anhydrous degassed CHCl3 (30 ml). The reaction
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¨
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13 K. B. Simonsen, N. Svenstrup, J. Lau, O. Simonsen, G. J.
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14 G. Sacarescu, L. Sacarescu, R. Ardeleanu, P. Kurcok and Z.
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15 F. S. Kipping, J. Chem. Soc., Trans., 1924, 125, 2291.
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17 T. Yamamoto and T. Shimizu, J. Mater. Chem., 1997, 7, 1967.
18 T. Yamamoto, W. Yamada, M. Takagi, K. Kizu, T. Maruyama,
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1
yield: 39% (0.95 g). Mn = 10 238, Mw/Mn = 2.20. H NMR
[400 MHz, CDCl3] d: 7.40–6.97 (Si–Ph), 4.48–4.62 (PhCH2S),
2.79–2.98 (TTF: SCH2–, SCH3), 0.89–1.89 (TTF: –CH2–,
–CH3). 13C NMR [100 MHz, CDCl3]: d 135.1–127.2 (Ph–C
and TTF ring-C), 116.9–117.3 (TTF ring-C), 46.5, 31.3, 29.9,
28.4, 27.3, 19.1, 16.7, 15.0, À6.3 (Si–CH3). Anal. for polymer
P1: C, 6.25, H, 57.39, S, 19.75%.
Synthesis of polymer P2
19 L. L. Dennis, R. L. Johnston, K. Hinkelmann, T. Suzuki and F.
Wudl, J. Am. Chem. Soc., 1990, 112, 3302.
A mixture of 2-(4-vinylbenzylthio)-3-methylthio-6,7-bis(hexyl-
thio)tetrathiafulvalene (3.16 g, 5 mmol), polyhydrosilane
20 S. Frenzel, S. Arndt, R. Ma and K. Mullen, J. Mater. Chem., 1995,
10, 1529.
¨
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510 | New J. Chem., 2008, 32, 505–510