Synthesis and electrochemical properties of a chiral silyl-substituted tetrathiafulvalene derivative

Article abstract of DOI:10.1016/j.cclet.2014.01.018

A new chiral tetrathiafulvalene (TTF) derivative and related silyl-substituted 1,3-dithiole-2-(thi)one compounds were synthesized and characterized by ¹H NMR, ¹³C NMR, MS and IR spectra. Single crystal structure of the silyl-substituted 1,3-dithiole-2-one revealed the high degree of conjugation of the five-membered ring moiety in the compound. The electrochemical properties of the new TTF derivative were studied by cyclic voltammetry and the results indicated that the electron-donating ability of the chiral TTF derivative was similar to that of BEDT-TTF. The ΔE value for the new TTF derivative was smaller than those for TTF and BEDT-TTF, indicative of decreased Coulombic repulsion in the dicationic redox state. Formation of charge-transfer (CT) complex between the new donor and electron acceptor 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) was demonstrated.

Full text of DOI:10.1016/j.cclet.2014.01.018

Chinese Chemical Letters 25 (2014) 579–582
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Chinese Chemical Letters
journal homepage: www.elsevier.com/locate/cclet
Original article
Synthesis and electrochemical properties of a chiral silyl-substituted
tetrathiafulvalene derivative
Guo-Qi Liang, Zhong-Bao Zhang, Hong-Qi Li *, Ya-Ping Wang, Chun-Ying Xian
College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620, China
A R T I C L E I N F O
A B S T R A C T
Article history:
A new chiral tetrathiafulvalene (TTF) derivative and related silyl-substituted 1,3-dithiole-2-(thi)one
Received 7 October 2013
1
13
compounds were synthesized and characterized by H NMR, C NMR, MS and IR spectra. Single crystal
structure of the silyl-substituted 1,3-dithiole-2-one revealed the high degree of conjugation of the five-
membered ring moiety in the compound. The electrochemical properties of the new TTF derivative were
studied by cyclic voltammetry and the results indicated that the electron-donating ability of the chiral
Received in revised form 16 December 2013
Accepted 24 December 2013
Available online 17 January 2014
TTF derivative was similar to that of BEDT-TTF. The
DE value for the new TTF derivative was smaller than
Keywords:
those for TTF and BEDT-TTF, indicative of decreased Coulombic repulsion in the dicationic redox state.
Formation of charge-transfer (CT) complex between the new donor and electron acceptor 2,3-dichloro-
Tetrathiafulvalene
Chiral
5,6-dicyano-1,4-benzoquinone (DDQ) was demonstrated.
Silyl
ß 2014 Hong-Qi Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
Electrochemistry
1
. Introduction
structure. Herein, we report the synthesis and electrochemical
properties of the new silyl-substituted chiral TTF derivative.
Recently, the introduction of chirality into tetrathiafulvalene
TTF) received much attention and stimulated arise and rapid
(
2. Experimental
development of new research into so-called chiral conductors and
multifunctional materials. Various synthetic strategies for intro-
duction of chirality into TTF have been proposed [1], and a large
number of chiral TTF donors have been synthesized [2]. While the
majority of synthesized chiral TTF derivatives have been utilized in
preparation of conducting charge-transfer (CT) complexes and
radical cation salts [3], they are also interesting as redox-active
ligands for asymmetric synthesis [4], as chiroptical donors [5], and
in formation of organogel and supramolecular chirality [6]. We
have designed a novel silyl-substituted chiral TTF donor based on
All chemical reagents were purchased from commercial sources
and used as received unless otherwise stated. Melting points were
determined on a WRS-2A capillary melting apparatus, and the
1
13
quoted temperatures were uncorrected. H NMR and C NMR
spectra were recorded on a Bruker AM 400 spectrometer. CDCl
was used as the solvent and chemical shifts recorded were
internally referenced to Me Si (0 ppm). IR spectra were obtained
3
4
on a Thermo Electron Corporation Nicolet 380 FT-IR spectropho-
tometer. UV–vis spectra were recorded on a Hitachi U-3310
the following conception. Introduction of chalcogens in
a
À5
À1
spectrophotometer in CH
ture. Mass spectra were recorded on
spectrometer using electron ionization (EI) at 70 eV or an Agilent
000 LC-MS instrument (ESI, positive mode, 70–1000 amu).
Optical rotations were recorded at 589 nm on a Rudolph Autopol
I polarimeter using a 1 dm cell, and [ values are given in
deg cm g . X-ray crystal structure was measured on a
Bruker Smart CCD diffractometer by using Mo K radiation at
96(2) K. Voltammetric analysis was carried out in a standard
2
Cl
2
(c = 10 mol L ) at room tempera-
peripheral position is one of the most effective strategies for
chemical modification of TTF, to increase the dimensionality and
consequently improve the conductivity of the CT salts. In this
respect incorporation of silyl groups to TTF is an alternative way,
though less exploited compared to thiolate or thioether, as
reported by Avarvari et al. [7]. The new TTF derivative containing
a disiloxane motif may also be used in multifunctional materials
combining two or more physical properties, such as conductivity
and molecular sensing (towards metal ions), considering the
possible complexation effect of the S,O,Si-heterocycle in the
a
JEOL JMS-SX102A
6
a]
D
À1
0
2
–1
1
a
2
three-electrode cell with a CHI760 potentiostat at 293 K. The
working electrode was a platinum disc electrode and the auxiliary
electrode was a platinum wire. The reference electrode was a
À1
saturated calomel electrode (SCE, 0.1 mol L Bu
4
NClO
4
in CH
2
Cl
2
).
À1
*
Corresponding author.
The scanning speed was 100 mV s . Spectroscopic data of new
E-mail address: hongqili@dhu.edu.cn (H.-Q. Li).
compounds 7–9 were as follows:
1
001-8417/$ – see front matter ß 2014 Hong-Qi Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
http://dx.doi.org/10.1016/j.cclet.2014.01.018

5
80
G.-Q. Liang et al. / Chinese Chemical Letters 25 (2014) 579–582
1
7
: Yellow crystals, mp 76–78 8C; H NMR (400 MHz, CDCl
3
):
):
), 143.2 (C 55 C), 213.8 (C 55 S); MS (EI, 70 eV):
d
d
achieved by tosylation of 2 with p-toluene sulfonyl chloride in the
presence of triethylamine [12]. Thione 5 was synthesized by
referring to literature wherein ditosylate 3 was reacted with
disodium salt of 1,3-dithiole-2-thione-4,5-dithiolate in THF for
five days to afford 5 in 52% yield [13]. We tried to modify the
procedure in order to synthesize 5 in a higher yield and shorter
time. At first, we carried out the reaction in methanol. A solution of
sodium methoxide in methanol was added to compound 4 to
generate disodium 1,3-dithiole-2-thione-4,5-dithiolate, to which
3 was added and the suspension was stirred for two days. In this
case thione 5 was obtained in a low yield due to the poor solubility
of 3 in methanol. Then we carried out the reaction in a mixed
solvent of methanol/THF to get thione 5 in two days in 63% yield.
The thione was converted to the corresponding 1,3-dithiole-2-one
6 by reaction with mercuric acetate in high yield. Reaction
13
0
2
.20 (s, 12H, CH
.2 (SiCH
3
), 2.06 (s, 4H, CH
2
); C NMR (100 MHz, CDCl
3
3
), 24.2 (SiCH
2
+
m/z (%) 356 (M , 90), 149 (100), 163 (50), 131 (37), 70 (31), 164
–1
(
30), 173 (30), 134 (23); IR (KBr, cm ): n 2916, 1255, 1071, 836.
1
8
: Pale yellow solid, mp 85–86 8C; H NMR (400 MHz, CDCl
3
):
d
13
0
d
3
1
.19 (s, 12H, SiCH
3
), 2.02 (s, 4H, SiCH
2
); C NMR (100 MHz, CDCl
3
):
3 2
0.9 (SiCH ), 22.4 (CH ), 132.7 (C 55 C), 199.8 (C 55 O); MS (ESI): m/z
+
–1
04.4 (M + 1); IR (KBr, cm ):
155, 1083, 1071, 740 cm
9
n
2953, 2896, 1664, 1376, 1250,
À1
.
1
: Orange solid, mp 191–193 8C; H NMR (400 MHz, CDCl
3
):
), 2.64 (dd,
H, J = 13.1, 12.4 Hz), 3.26 (dd, 2H, J = 13.1, 3.8 Hz), 4.22 (dd, 2H,
d
0
2
3 3 2
.19 (s, 12H, SiCH ), 1.40 (s, 6H, CH ), 1.98 (s, 4H, SiCH
13
J = 12.4, 3.8 Hz); C NMR (100 MHz, CDCl
3
):
), 82 (CH), 112 (OCO), 134 (C 55 C), 135
2986, 2953, 2913, 2892, 1636, 1411, 1252,
3
d 3.26 (SiCH ), 24
(
(
1
SiCH
2 3 2
), 29 (CH ), 39 (CH
–1
C 55 C); IR (KBr, cm ):
113, 1209, 1071, 842, 797, 705; [
n
2 2
between TEA [Zn(DMIT) ] and 1,3-bis(chloromethyl)-1,1,3,3-
2
0
a
]
+ 79.6 (c 0.02, CHCl
3
).
tetramethyldisiloxane in acetone produced thione 7 in 81%
yield then it was converted to the corresponding 1,3-dithiole-
2-one 8 by reaction with mercuric acetate in 86% yield. Triethyl
phosphite-mediated cross-coupling between 6 and 8 afforded
D
3
. Results and discussion
1
13
The synthetic route to chiral TTF derivative 9 was showed in
Scheme 1. Preparation of compound 1 involves the protection of
,2-diol. It was reported that compound 1 could be prepared by
refluxing a solution of diethyl -tartrate, p-toluenesulfonic acid
and 2,2-dimethoxypropane in benzene [8]. We tried to use
toluene instead of toxic benzene as solvent to synthesize 1 but
found that more by-products were formed, decreasing yield of 1.
the new chiral TTF derivative 9 in 31% yield. The H NMR and
C
NMR spectrum (Fig. S1 and Fig. S2, respectively in Supporting
information) of chiral TTF 9 were obtained and all the spectral
data were in good accordance with the structure of the new
compound.
Single crystal structure of 8 is shown in Fig. 1. Compound 8
crystallizes in the triclinic system with space group P–1 (Table S1
1
L
˚
Feit [9] prepared 1 from diethyl
L
-tartrate and acetone which plays
in Supporting information). The C(1)–O(1) distance [1.205(2) A] is
a dual-effect of reagent and solvent. However, the reaction took
within the normal range of a typical C 55 O double bond (Table S2 in
nine days to complete. We improved synthesis of 1 by refluxing a
Supporting information). The C–S bond lengths out of the five-
˚
solution of diethyl
L
-tartrate, p-toluenesulfonic acid and 2,2-
membered dithiole ring are 1.825(3) and 1.815(2) A for C(4)–S(3)
dimethoxypropane in acetone. The reaction was finished in
several hours to afford 1 in a high yield of 93%. Reduction of
compound 1 with sodium borohydride and lithium chloride gave
and C(9)–S(4) bond, respectively. While the C–S bond lengths in
the five-membered ring are shorter than a typical C–S single bond
˚
˚
[range 1.746(2)–1.772(2) A]. The C 55 C bond length [1.343(3) A] in
the five-membered ring is slightly longer than a normal double
bond. This shows the high degree of conjugation of the five-
membered dithiole ring moiety in compound 8 (Fig. S3 in
Supporting information).
2
in 76% yield. Sodium borohydride alone does not reduce esters
under ambient conditions, but the reactivity of sodium borohy-
dride can be enhanced by the addition of certain additives such as
lithium chloride [10] and iodine [11]. Conversion of 2–3 was
Me CO(OMe)
2
EtO2C
2
O
O
EtO2C
EtO2C
OH
OH
O
O
O
O
TsOH/acetone
NaBH /LiCl
HO
HO
TsCl/Et3N
72%
TsO
TsO
4
7
6%
9
3%
EtO2C
1
2
3
SCOPh
SCOPh
S
S
S
S
S
S
S
S
S
O
O
S
S
O
4
Hg(OAc) /HOAc
2
MeONa
O
S
S
9
2%
63%
O
6
5
S
S
S
S
S
Zn
S
S
S
S
S
Si
Si
Si
S
S
O(SiMe CH Cl)
Hg(OAc)2
86%
2
2
2
Et N
S
S
O
4
2
O
O
8
1%
S
S
Si
S
S
TEA [Zn(DMIT) ]
2
2
7
8
S
S
S
Si
O
Si
6/P(OEt)3
1%
S
S
S
O
O
3
S
S
9
Scheme 1. Synthetic route to chiral TTF derivative 9.

G.-Q. Liang et al. / Chinese Chemical Letters 25 (2014) 579–582
581
Crystal structure of the silyl-substituted 1,3-dithiole-2-one
revealed the high degree of conjugation of the five-membered
ring in the compound. Cyclic voltammetry of the chiral TTF
derivative showed that its electron-donating ability was similar to
that of BEDT-TTF. The
DE value for the new TTF derivative was
smaller than those for TTF and BEDT-TTF, indicative of decreased
Coulombic repulsion in the dicationic redox state. Formation of CT
complex between the new donor and DDQ was demonstrated.
Apart from as a promising precursor for conducting CT complexes
and salts, the new TTF derivative may be used in multifunctional
materials.
Acknowledgment
The authors acknowledge the support by ‘‘the Fundamental
Research Funds for the Central Universities’’.
Fig. 1. Crystal structure of compound 8.
2
1
1
0
5
0
5
0
5
Appendix A. Supplementary data
Supplementary data associated with this article can be found, in
the online version, at http://dx.doi.org/10.1016/j.cclet.2014.01.018.
References
[
[
1] N. Avarvari, J.D. Wallis, Strategies towards chiral molecular conductors, J. Mater.
Chem. 19 (2009) 4061–4076.
2] (a) A. Saad, F. Barri e` re, E. Levillain, et al., Persistent mixed-valence [(TTF)
+
2
] * dyad
of a chiral bis(binaphthol) tetrathiafulvalene (TTF) derivative, Chem. Eur. J. 16
-
(2010) 8020–8028;
(b) S.J. Yang, A.C. Brooks, L. Martin, et al., Novel enantiopure bis(pyrrolo)tetrathia-
0.2
0.4
0.6
0.8
1.0
1.2
fulvalene donors exhibiting chiral crystal packing arrangements, CrystEngComm
11 (2009) 993–996;
Potential / V (vs. SCE)
(
c) M. Chas, F. Riob e´ , R. Sancho, C. Minguillon, N. Avarvari, Selective monosulfox-
idationof tetrathiafulvalenesintochiralTTF-sulfoxides,Chirality21(2009) 818–825;
2 2
Fig. 2. Cyclic voltammogram of the chiral TTF derivative 9 in CH Cl .
(
d) C. R e´ thor e´ , A. Madalan, M. Fourmigu e´ , et al., OÁÁÁS vs. NÁÁÁS intramolecular
nonbonded interactions in neutral and radical cation salts of TTF-oxazoline deriva-
tives: synthesis, theoretical investigations, crystalline structures, and physical prop-
erties, New J. Chem. 31 (2007) 1468–1483;
The electrochemical properties of the chiral TTF derivative 9
were studied in methylene dichloride solution by cyclic voltam-
metry and the cyclic voltammogram of 9 in methylene dichloride
(
e) C. R e´ thor e´ , M. Fourmigu e´ , N. Avarvari, Tetrathiafulvalene-hydroxyamides and -
oxazolines: hydrogen bonding, chirality, and a radical cation salt, Tetrahedron
1 (2005) 10935–10942;
6
–3
–1
solution (10 mol L ) was shown in Fig. 2. The new TTF derivative
exhibited two reversible redox waves. The half-wave oxidation
(f) C. R e´ thor e´ , M. Fourmigu e´ , N. Avarvari, Tetrathiafulvalene based phosphino-
oxazolines: a new family of redox active chiral ligands, Chem. Commun. (2004)
1384–1385;
1
2
potentials of 9 (E1/2 and E1/2 ) are larger than those of TTF but are
(g) S. Matsumiya, A. Izuoka, T. Sugawara, T. Taruishi, Y. Kawada, Effect of methyl
1
close to those of BEDT-TTF [14]. The difference between E1/2
substitutionon conformation and molecular arrangement of BEDT-TTF derivatives in
the crystalline environment, Bull. Chem. Soc. Jpn. 66 (1993) 513–522;
2
2
1
and E1/2
(
D
E = E1/2 À E1/2 ) for 9 is smaller than those for TTF
(h) J.D. Wallis, A. Karrer, J.D. Dunitz, Chiral metals? A chiral substrate for organic
and BEDT-TTF, indicative of decreased Coulombic repulsion in
conductors and superconductors, Helv. Chim. Acta 69 (1986) 69–70.
the dicationic redox state of 9. The HOMO level of 9 was estimated
[
3] (a) F. Pop, P. Auban-Senzier, A. Fr a˛ ckwiak, et al., Chirality driven metallic versus
semiconducting behavior in a complete series of radical cation salts based on
dimethyl-ethylenedithio-tetrathiafulvalene (DM-EDT-TTF), J. Am. Chem. Soc. 135
from the first onset of the oxidation potential [EHOMO = À
ox
(E
onset + 4.4) eV] [15] to be À5.11 eV, which makes it suitable for
(2013) 17176–17186;
use as p-type organic semiconductor [16]. Therefore compound 9may
be a good precursor for preparation of conducting CT complexes and
radical cation salts.
(b) F. Pop, S. Laroussi, T. Cauchy, et al., Tetramethyl-bis(ethylenedithio)-tetra-
thiafulvalene (TM-BEDT-TTF) revisited: crystal structures, chiroptical properties,
theoretical calculations, and a complete series of conducting radical cation salts,
Chirality 25 (2013) 466–474;
The UV–vis absorption spectra of donor 9 and 9–DDQ CT
(
c) A. Saad, O. Jeannin, M. Fourmigu e´ , Chiral, flexible binaphthol-substituted
tetrathiafulvalenes, Tetrahedron 67 (2011) 3820–3829;
d) A.M. Madalan, C. R e´ thor e´ , M. Fourmigu e´ , et al., Order versus disorder in chiral
–5
–1
complex in methylene dichloride (10 mol L ) were measured at
room temperature (Fig. S4 in Supporting information). Donor 9
alone showed two strong absorption peaks at 325 nm and 405 nm.
Upon mixing of 9 with DDQ, a new CT band at 425 nm was visible,
confirming the formation of CT complex between 9 and DDQ. It
demonstrated the usefulness of the new donor for preparation of
CT complexes with suitable electron acceptors such as DDQ.
Further studies in this aspect are underway.
(
tetrathiafulvalene-oxazoline radical-cation salts: structural and theoretical inves-
tigations and physical properties, Chem. Eur. J. 16 (2010) 528–537;
(e) M. Chas, M. Lemari e´ , M. Gulea, N. Avarvari, Chemo- and enantioselective
sulfoxidation of bis(ethylenedithio)-tetrathiafulvalene (BEDT-TTF) into chiral
BEDT-TTF-sulfoxide, Chem. Commun. (2008) 220–222;
(
f) C. R e´ thor e´ , N. Avarvari, E. Canadell, P. Auban-Senzier, M. Fourmigu e´ , Chiral
molecular metals: syntheses, structures, and properties of the AsF6 salts of
–
racemic (Æ)-, (R)-, (S)-tetrathiafulvalene-oxazoline derivatives, J. Am. Chem.
Soc. 127 (2005) 5748–5749;
(g) A. Karrer, J.D. Wallis, J.D. Dunitz, et al., Structures and electrical properties
of some new organic conductors derived from the donor molecule TMET (S,S,S,S-
bis(dimethylethylenedithio)tetrathiafulvalene), Helv. Chim. Acta 70 (1987)
4
. Conclusion
9
42–953.
[
4] (a) C. R e´ thor e´ , F. Riob e´ , M. Fourmigu e´ , et al., Tetrathiafulvalene–oxazoline
ligands in the iridium catalyzed enantioselective hydrogenation of arylimines,
Tetrahedron: Asymmetry 18 (2007) 1877–1882;
In conclusion, a new silyl-substituted chiral TTF derivative and
related 1,3-dithiole-2-(thi)one compounds were synthesized.

5
82
G.-Q. Liang et al. / Chinese Chemical Letters 25 (2014) 579–582
(
b) C. R e´ thor e´ , I. Suisse, F. Agbossou-Niedercorn, et al., Chiral tetrathiafulvalene
based phosphine- and thiomethyl-oxazoline ligands. Evaluation in palladium
catalysed asymmetric allylic alkylation, Tetrahedron 62 (2006) 11942–11947;
through silicon or germanium double bridges in rigid bis(tetrathiafulvalenes),
Chem. Eur. J. 13 (2007) 5394–5400.
[8] (a) M. Carmack, C.J. Kelley, The synthesis of the optically active Cleland reagent
(
c) A. Chesney, M.R. Bryce, Chiral oxazolines linked to tetrathiafulvalene (TTF):
redox-active ligands for asymmetric synthesis, Tetrahedron: Asymmetry 7 (1996)
247–3254.
5] (a) T. Biet, A. Fihey, T. Cauchy, et al., Ethylenedithio-tetrathiafulvalene-helicenes:
[(À)-1,4-dithio-L
g
-threitol], J. Org. Chem. 33 (1968) 2171–2173;
(b) A.F. Rodney, An efficient synthesis of (À)-posticlure: the sex pheromone of
3
Orgyia postica, Eur. J. Org. Chem. (2007) 5064–5070;
[
(c) P.M. Chincholkar, A.S. Kale, V.K. Gumaste, A.R.A.S. Deshmukh, An efficient
formal synthesis of (S)-dapoxetine from enantiopure 3-hydroxy azetidin-2-one,
Tetrahedron 65 (2009) 2605–2609.
electroactive helical precursors with switchable chiroptical properties, Chem. Eur.
J. 19 (2013) 13160–13167;
(
b) Y.L. Si, G.C. Yang, Z.M. Su, Chiroptical, linear, and second-order nonlinear
[9] P.W. Feit, 1,4-Bismethanesulfonates of the stereoisomeric butanetetraols and
related compounds, J. Med. Chem. 7 (1964) 14–17.
optical properties of tetrathiafulvalenylallene:
material, J. Mater. Chem. C 1 (2013) 1399–1406;
a multifunctional molecular
[10] A.E. Wr o´ blewski, I.E. Głowacka, Enantiomerically pure 4-amino-1,2,3-trihydrox-
ybutylphosphonic acids, Tetrahedron 61 (2005) 11930–11938.
[11] M. Periasamy, M. Thirumalaikumar, Methods of enhancement of reactivity and
selectivity of sodium borohydride for applications in organic synthesis, J. Orga-
nomet. Chem. 609 (2000) 137–151.
(c) M. Hasegawa, Y. Sone, S. Iwata, H. Matsuzawa, Y. Mazaki, Tetrathiafulvale-
nylallene: a new class of donor molecules having strong chiroptical properties in
neutral and doped states, Org. Lett. 13 (2011) 4688–4691.
6] (a) C. Wang, F. Sun, D.Q. Zhang, et al., Cholesterol-substituted tetrathiafulvalene
[
(
TTF) compound: formation of organogel and supramolecular chirality, Chin. J.
Chem. 28 (2010) 622–626;
b) I. Danila, F. Riob e´ , J. Puigmart ı´ -Luis, et al., Supramolecular electroactive
[12] G. Liu, Z. Wang, Total synthesis of koninginin D, B and E, Synthesis (2001)
119–127.
[13] G.A. Horley, T. Ozturk, F. Turksoy, J.D. Wallis, New substrates for the preparation
of electroactive materials: the syntheses of chiral tetrathiafulvalene derivatives
with hydroxyfunctionalised butane-1,4-dithio bridges, J. Chem. Soc., Perkin
Trans. 1 (1998) 3225–3231.
(
3
organogel and conducting nanofibers with C -symmetrical architectures, J. Mater.
Chem. 19 (2009) 4495–4504;
(
c) I. Danila, F. Pop, C. Escudero, et al., Twists and turns in the hierarchical
self-assembly pathways of a non-amphiphilic chiral supramolecular material,
Chem. Commun. 48 (2012) 4552–4554;
[14] K. Zong, W. Chen, M.P. Cava, R.D. Rogers, Synthesis and properties of bis(2,5-
dimethylpyrrolo[3,4-d]) tetrathiafulvalenes, a class of annelated tetrathiafulva-
lene derivatives with excellent electron donor properties, J. Org. Chem. 61 (1996)
8117–8124.
[15] L. Wang, H. Cho, S.H. Lee, et al., Liquid crystalline mesophases based on symmetric
tetrathiafulvalene derivatives, J. Mater. Chem. 21 (2011) 60–64.
[16] A.R. Murphy, J.M.J. Fr e´ chet, Organic semiconducting oligomers for use in thin film
transistors, Chem. Rev. 107 (2007) 1066–1096.
(
d) I. Danila, F. Riob e´ , F. Piron, et al., Hierarchical chiral expression from the nano-
to mesoscale in synthetic supramolecular helical fibers of a nonamphiphilic C
symmetrical p-functional molecule, J. Am. Chem. Soc. 133 (2011) 8344–8353.
3
-
[
7] (a) A. Hameau, F. Guyon, M. Knorr, et al., Synthesis and reactivity of silylated
tetrathiafulvalenes, Dalton Trans. 36 (2008) 4866–4876;
(b) F. Biaso, M. Geoffroy, E. Canadell, et al., Intramolecular mixed-valence state