@misc{oai:ir.soken.ac.jp:00000149,
 author = {小嵜, 正敏 and コザキ, マサトシ and KOZAKI, Masatoshi},
 month = {2016-02-17, 2016-02-17},
 note = {Introduction 
　　Recently much attention has been focused on conducting polymers due to their novel electrical electrochemical, and optical properties. Especially conducting polymers such as poly(pyrrole) and poly(thiophene), which can be electrochemically prepared, are of interest as promising candidates for organic batteries or transistors, because their properties are electrochemically adjustable and their thin films are easily produced. The preparation of new conducting polymers with better physical properties is very important for the promotion of the application as well as for the basic researches. In this study some novel conducting polymers were electrochemically prepared and their properties were investigated.

Poly( 2 - (2, 4-cyclopentadien- 1 ylidene) - 1, 3-di thioles)
　　Though there are many works for conducting polymers constructed of five-membered heterocycles, polymers consisting of five-membered carbon rings are rare. On the other hand, it was predicted that the introduction of 1,3-dithiole groups into a conducting polymer would cause strong interchain interactions, extended p-conjugation, and high polarization which are useful for the improvement of conducting properties. Therefore, the author designed poly(2-(2, 4-cyclopentadien-1-yldene)-1, 3-dithioles) (1) which consist of five-membered carbon skeletons bonded to 1,3-dithiole groups via a cross conjugation. Nonsubstituted polymer la and its benzo derivative 1b prepared by electrochemical polymerization were unstable to potential. The stability of the polymer was somewhat improved by the introduction of methy. I groups at the β-position of the cyclopentadiene rings, so that the oxidation peak was observed at a lower potential in the cyclic voltammogram. This polymer 1c showed a cathodic peak away from an anodic peak, indicating that the oxidation of 1c was accompanied by a large conformational change. MNDO-PM3 calculations show that the dihedral angle between the monomers is 93" in the most stable conformation of the dimer derived from 1a, whereas that for its radical cation is 171'

Poly(thiophenes) Containing 1, 3-Dithiol-2-yldene Moieties 
　　In order to improve the stability of poly(2-(2, 4- cyclopentadien-1 ylidene)-1, 3-dithiole), analogous thiophene-fused polymers, poly(4  (1, 3-dithiol-2-ylidene) -4H-cyclopenta[2, 1 b;3, 4-b' ]dithiophenes) (2) and poly(7-(1, 3-dithiol-2-ylidene) -7H-cyclopenta[1, 2-b;4, 3-b' ]dithiophenes) (3) were designed. The corresponding monomers were synthesized by Wittig-Horner or Wittig reactions. The X-ray structural analyses of the parent compounds reveal that both molecules haveplanar structures with short intermolecular S･･･S contacts and the molecule of the monomer of 3 additlonally has short intramolecular S･･･S contacts. They have low oxidation potentials and absorptions in a long wavelength region due to the 1,3-dithiole skeleton. An electrochemical oxidation afforded the corresponding polymers 2 and 3, which have low oxidation potentials. They were much stable to potential than 1. Electrochemically dedoped films of 2 and 3 have interband absorptions at 610-690nm and 420-590nm, respectively, in their electronic spectra. Some films exhibited high electrical conductivities with doping. Derivatives, containing linear alkyl chains, were synthesized in order to enhance solubilities in organic solvents and were found to be somewhat soluble in THF and chloroform. MNDO-PM3 calculations show that the torsion angles between the neighbor monomer fragments in the dimers and the trimers are about 30゜ which is almost similar to that of bithiophene. However, the oligomers derived from the monomer of 2 have more extended conjugated systems than those of 3, which was indicated by INDO/1-CI calculations. 

Poly(thiophenes) Connected by Azine Groups 
　　Poly(4H-cyclopenta[2, 1-b;3, 4-b' ]dithiophene-4-one azine) (4) and poly(7H-cyclopenta[1, 2-b;4, 3-b' ]dithiophene-7-0ne azine) (5) are very interesting since they seem to make a two-dimensional network structure and have a low band gap. 
  The monomers were prepared by the dehydrating condensation reaction of the corresponding ketones with hydrazine. The X-ray structural analysis of the monomer of 4 shows that the molecule is planar. The cyclic voltammograms of both monomers of 4 and 5 showed irreversible two-electron oxidation and two quasi-reversible one-electron reduction waves corresponding to the formation of dication, anion, and dianion, respectively. Their absorptions were observed in a long wavelength region in their electronic spectra. Polymer 4 was prepared by an electrochemical oxidation as a free standing film. On the other hand, 5 could not be prepared by an electrochemical method. Electrochemically dedoped 4 showed an absorption edge at 1.4eV. MNDO-PM3 calculations show that the monomers of 4 and 5 have three almost degenerating orbitals as HOMOs. The calculations for the monomer of 4 showing a large atomic orbital coefficient at the α-positions in HONOs predict that polymerization would proceed at these positions, which was proved by the fact that the polymerization was prevented by the introduction of a methyl group on the α-positions of the monomer of 4., 総研大甲第78号},
 title = {シクロペンタジエニリデン骨格を有する新規導電性高分子に関する研究},
 year = {}
}