Furan- and pyrrole-containing analogs of α-quinquethiophene: spectroscopic and electrochemical properties

A series of pentacyclic analogs of α-quinquethiophene containing one or two furan or pyrrole units has been synthesized. The synthesis is based on the cyanide-catalyzed Stetter reaction, providing the ketonic precursors to the pentacycles. Spectral and electrochemical investigations show that the redox-stable mixed pentacycles display hypsochromic shifts in their absorption maxima, as well as a greater ease of oxidation, in comparison to α-quinquethiophene.