Synthesis and properties of alkoxy-substituted oligothiophene derivatives

Abstract

Three oligothiophenes containing alkoxy groups were synthesized, and their optical, electrochemical, and electrical properties were investigated. The oligothiophenes were soluble in common organic solvents owing to the presence of flexible alkyl chains in their alkoxy groups. The introduction of alkoxy groups induced a red-shift in the absorption and emission bands and a negative shift in the oxidation potentials observed for the compounds. The extension of the π-conjugation system enhanced the stability of the oxidized states of the oligothiophenes due to a reduction in the Coulombic repulsion. The electrochemically oxidized dodecathiophene showed excellent electrical conductivity.