Synthesis and electropolymerisation of 3′,4′-bis(alkylsulfanyl)terthiophenes and the significance of the fused dithiin ring in 2,5-dithienyl-3,4-ethylenedithiothiophene (DT-EDTT)

A new series of regioregular poly(terthiophenes), bearing bis(thioether) side groups, has been prepared by electrochemical oxidation. Cyclic voltammetry of the parent trimers reveals an increase in electron donating ability in cyclic thioether derivatives. For example, one compound containing a central ethylenedithiothiophene (EDTT) unit gives two irreversible oxidation peaks which are significantly lower than the corresponding values for the structurally analogous bis(methylthio) derivative (ΔE1ox = 170 mV, ΔE2ox = 30 mV). The difference in oxidation potentials of each terthiophene in acetonitrile solution can be explained by examining the highest occupied molecular orbital (HOMO) energies. The electrochemical behaviour of the polymers illustrates the increase in p-doping ability of the EDTT-containing polymer. The cyclic voltammograms and electronic absorption spectra of the polymers show that the polymers containing cyclic thioether units have the lowest bandgap in the series (ca. 1.4 V and 1.5 eV, respectively). Photoinduced IR spectroscopy of poly(dithienyl-3,4-ethylenedithiothiophene) provides evidence of a long-living photoexcited charged state in the polymer.

[1]  P. Skabara,et al.  3,4-Disubstituted terthiophene systems: synthesis and electropolymerization , 2001 .

[2]  B. Batlogg,et al.  Gate-induced superconductivity in a solution-processed organic polymer film , 2001, Nature.

[3]  N. S. Sariciftci,et al.  Vibrational Spectroscopy on pDTT3A Low Band Gap Polymer Based on Dithienothiophene , 2001 .

[4]  N. S. Sariciftci,et al.  Photoexcited spectroscopy and in situ electrochemical spectroscopy in conjugated polymers: a comparative study , 2001 .

[5]  B. Patrick,et al.  Electropolymerization of a Cyclometalated Terthiophene: A Hybrid Material with a Palladium−Carbon Bond to the Backbone , 2000 .

[6]  J. Reynolds,et al.  Poly(3,4‐ethylenedioxythiophene) and Its Derivatives: Past, Present, and Future , 2000 .

[7]  R. Janssen,et al.  Synthesis and characterization of new copolymers of thiophene and vinylene: Poly(thienylenevinylene)s and poly(terthienylenevinylene)s with thioether side chains , 1999 .

[8]  H. Randriamahazaka,et al.  Nucleation and growth of poly(3,4-ethylenedioxythiophene) in acetonitrile on platinum under potentiostatic conditions , 1999 .

[9]  I. F. Perepichka,et al.  Novel Terthiophene and Bis(thienyl)furan Derivatives as Precursors to Highly Electroactive Polymers , 1999 .

[10]  S. Ng,et al.  Electrochemical Synthesis and Characterization Studies of Poly[3,3`-dialkylsulfanyl-2,2`-bithiophene] Films , 1999 .

[11]  Christoph J. Brabec,et al.  Photovoltaic properties of conjugated polymer/methanofullerene composites embedded in a polystyrene matrix , 1999 .

[12]  R. Seeber,et al.  Polymerization and Characterization of 4,4’-bis(alkylsulfanyl)-2,2’-bithiophenes , 1999 .

[13]  J. Roncali,et al.  Electrosynthesis of Highly Electroactive Tetrathiafulvalene‐Derivatized Polythiophenes , 1998 .

[14]  J. Roncali,et al.  Electrochemical synthesis of poly(3,4-ethylenedioxythiophene) from a dimer precursor , 1998 .

[15]  S. Sadki,et al.  Electropolymerization of 3,4-ethylenedioxythiophene and 3,4-ethylenedioxythiophene methanol in the presence of dodecylbenzenesulfonate , 1998 .

[16]  O. Stéphan,et al.  Electrochemical behaviour of 3, 4-ethylenedioxythiophene functionalized by a sulphonate group. Application to the preparation of poly(3, 4-ethylenedioxythiophene) having permanent cation-exchange properties , 1998 .

[17]  J. Reynolds,et al.  In situ conductivity studies of poly(3,4-ethylenedioxythiophene) , 1998 .

[18]  John P. Campbell,et al.  From Monomers to π-Stacks. A Comprehensive Study of the Structure and Properties of Monomeric, π-Dimerized, and π-Stacked Forms of the Cation Radical of 3‘,4‘-Dibutyl-2,5‘‘-diphenyl-2,2‘:5‘,2‘‘-terthiophene , 1997 .

[19]  J. Roncali.  Synthetic Principles for Bandgap Control in Linear pi-Conjugated Systems. , 1997, Chemical reviews.

[20]  Simon J. Higgins,et al.  Conjugated polymers incorporating pendant functional groups—synthesis and characterisation , 1997 .

[21]  H. Neugebauer,et al.  FTIR ATR spectroelectrochemical investigations of polyaniline with perrhenate as a new doping system , 1996 .

[22]  John P. Campbell,et al.  Single-Crystal X-ray Structure of the Cation Radical of 3‘,4‘-Dibutyl-2,5‘‘-diphenyl-2,2‘:5‘,2‘‘-terthiophene: Definitive Evidence for π-Stacked Oxidized Oligothiophenes , 1996 .

[23]  Tian-An Chen,et al.  Synthesis of Regioregular Head-to-Tail Poly[3-(alkylthio)thiophenes]. A Highly Electroconductive Polymer , 1995 .

[24]  H. Neugebauer.  In situ vibrational spectroscopy of conducting polymer electrodes , 1995 .

[25]  M. Kanatzidis,et al.  Determination of ground- and excited-state isomerization barriers for the oligothiophene 3',4'-dibutyl-2,2':5',2''-terthiophene , 1993 .

[26]  A. J. Heeger,et al.  Photoinduced Electron Transfer from a Conducting Polymer to Buckminsterfullerene , 1992, Science.

[27]  J. Roncali.  Conjugated poly(thiophenes): synthesis, functionalization, and applications , 1992 .

[28]  K. Müllen,et al.  Electronic and structural properties of polyparaphenylenevinylene from the vibrational spectra , 1991 .

[29]  J. Reynolds,et al.  Soluble Ethylmercapto Substituted Polythiophenes , 1989 .

[30]  Susumu Tanaka,et al.  Electrochemical preparation and properties of poly(3-methoxy-2,5-thiophenediyl) and poly(3-methylthio-2,5-thiophenediyl) , 1988 .

[31]  Vardeny,et al.  Amplitude and phase modes in trans-polyacetylene: Resonant Raman scattering and induced infrared activity. , 1987, Physical review. B, Condensed matter.

[32]  R. L. Elsenbaumer,et al.  Processible and environmentally stable conducting polymers , 1986 .

[33]  G. Tourillon,et al.  Structural effect on the electrochemical properties of polythiophene and derivatives , 1984 .

[34]  G. Tourillon,et al.  Effect of dopant on the physicochemical and electrical properties of organic conducting polymers , 1983 .

[35]  Olga Kennard,et al.  Systematic analysis of structural data as a research technique in organic chemistry , 1983 .

[36]  R. Waltman,et al.  Electrochemical studies of some conducting polythiophene films , 1983 .