ISSN 0012ꢀ5008, Doklady Chemistry, 2016, Vol. 467, Part 1, pp. 94–99. © Pleiades Publishing, Ltd., 2016.
Original Russian Text © M.L. Keshtov, S.A. Kuklin, D.Yu. Godovskii, I.O. Konstantinov, M.M. Krayushkin, A.S. Peregudov, A.R. Khokhlov, 2016, published in Doklady Akademii
Nauk, 2016, Vol. 467, No. 1, pp. 48–53.
CHEMICAL
TECHNOLOGY
Synthesis and Optical and Electrochemical Properties
of 5,6ꢀBis[9ꢀ(2ꢀdecyltetradecyl)ꢀ9Hꢀcarbazolꢀ3ꢀyl]naphtho[2,1ꢀ
b:3,4ꢀb']dithiophene as a Promising Building Block
for Photovoltaic Applications
M. L. Keshtova, S. A. Kuklina, D. Yu. Godovskiia, I. O. Konstantinova,
M. M. Krayushkinb, A. S. Peregudova, and Academician A. R. Khokhlova
Received November 6, 2015
Abstract—A new carbazoleꢀcontaining naphthodithiophene heteroaromatic compound, 5,6ꢀbis[9ꢀ(2ꢀ
decyltetradecyl)ꢀ9 ꢀcarbazolꢀ3ꢀyl]naphtho[2,1ꢀ :3,4ꢀ ']dithiophene (M1), was synthesized to be subseꢀ
H
b
b
quently used as the weak donor structure for the construction of narrow bandgap D–A conjugated polymers
in terms of the “weak donor–strong acceptor” concept. The composition and structure of M1 were conꢀ
firmed by the data of elemental analysis and IR and 1H and 13C NMR spectroscopy. The optical and electroꢀ
chemical characteristics of the product were measured. The compound M1 was shown to have lowꢀlying
HOMO (–5.57 eV), which is favorable for high openꢀcircuit voltage and to be suitable as a promising weak
donor moiety in the D–A conjugated polymer for photovoltaic applications.
DOI: 10.1134/S0012500816030022
In recent years, considerable attention has been naphthalene moiety and representing planar strucꢀ
devoted to organic semiconductors as promising
materials for optoelectronic applications. Most of the
studied organic semiconductors are based on the synꢀ
tures with a
intramolecular
π
ꢀconjugated system favorable for strong
π
ꢀconjugation and intermolecular
π
ꢀ
stacking [8]. Naphthodithiophene derivatives with
clearꢀcut weak donor properties incorporated in conꢀ
jugated D–Aꢀcopolymers lower the highest occupied
molecular orbital (HOMO) level, which increases the
openꢀcircuit voltage, and, as a consequence, they
increase the efficiency of polymeric solar cell [9].
Recently, Wong and coꢀworkers [10] synthesized the
D–A copolymer with a narrow bandgap (1.6 eV) and
lowꢀlying HOMO (–5.22 eV) based on 5,6ꢀdialkoxꢀ
ynaphthodithiophene derivatives and employed this
copolymer to design solar cells with a bulk heterojuncꢀ
tion of 5.3% efficiency not inferior to world analogs.
The low position of the HOMO led to high openꢀcirꢀ
cuit voltage (Vхх = 0.68 V) and, hence, to higher effiꢀ
ciency [10]. You and coꢀworkers [11] proposed one
more novel naphthodithiopheneꢀcontaining narrow
bandgap polymer, approaching the “ideal polymer,”
with a band gap of 1.59 eV and lowꢀlying HOMO
(–5.35 eV) [11].
thesis of
π
ꢀconjugated structures such as oligothꢀ
iophenes [1], oligofluorenes [2], polycyclic aromatic
compounds [3], and fused heterocyclic aromatic
structures [4]. A special place in the series of these
compounds is occupied by fused thiophene derivaꢀ
tives, which are of interest from both scientific and
practical standpoints. In view of the unusual elecꢀ
tronic and optical features and high chemical and
thermal stabilities, these compounds are tested as
active layers for field effect transistors [5], light emitꢀ
ting diodes [6], and organic solar cells [7]. In particuꢀ
lar, fused thiophene derivatives are studied owing to
their planar geometry providing good ꢀstacking and
π
highly ordered molecular structure promoting effiꢀ
cient charge transfer.
Among these promising classes of heteroaromatic
compounds are naphthodithiophene (NDT) derivaꢀ
tives containing two thiophene rings fused with a
Here we developed and synthesized a new monoꢀ
mer, 5,6ꢀbis[9ꢀ(2ꢀdecyltetradecyl)ꢀ9 ꢀcarbazolꢀ3ꢀ
H
a Nesmeyanov Institute of Organoelement Compounds,
Russian Academy of Sciences, ul. Vavilova 28, Moscow,
119991 Russia
b Zelinskii Institute of Organic Chemistry, Russian Academy
of Sciences, Leninskii pr. 47, Moscow, 119991 Russia
eꢀmail: keshtov@ineos.ac.ru; ineosꢀ50@mail.ru
yl]naphtho[2,1ꢀ :3,4ꢀ ']dithiophene (M1), based
b
b
on NDT containing carbazole moieties in the 5ꢀ and
6ꢀpositions (Scheme 1). As noted above, compounds
of this type form highly ordered
π
ꢀstacked structures,
which enhances the hole conductivity.
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