Synthesis of Soluble Polythiophene Partially Containing 3,4-Ethylenedioxythiophene and 3-Hexylthiophene by Polycondensation

A novel poly(quinquethiophene) partially containing 3,4-ethylenedioxythiophene (EDOT) and 3-hexylthiophene, poly(3,3 ''''-dihexyl-3',4',3''',4'''-diethylenedioxy-2,2':5',2'':5'',2''':5''',2''''-quinquethiophene), was synthesized by three types of polycondensations. Among them, direct C-H coupling reaction gave the polymer with the highest molecular weight. The resulting polymer was soluble in common organic solvents. Absorption and fluorescence spectra of the polymer showed a remarkable red-shift compared with the corresponding monomer due to the expansion of effective π-conjugation length.