Synthesis and Electronic Properties of Alternating α,α‘-Thiophene-Phosphole Oligomers

Abstract
Alternating thiophene-phosphole oligomers up to seven rings in length have been synthesized. A regular decrease of the HOMO−LUMO gap is observed upon increasing the length of the π-conjugated system. The nature of the P-moieties dramatically influences the optical and electrochemical properties of these phosphole-based oligomers. Electro-oxidation of derivative 5a afforded an electroactive polymer exhibiting reversible p-doping.