A facile synthesis of α-substituted thiophenes from a functionalized 2-aminothiophene by homo- and cross-coupling reactions

A series of new α-substituted thiophenes with elongated π-conjugation are prepared by homo- and cross-coupling reactions. An efficient one-step synthesis of a key intermediate, a substituted 2-iodothiophene, via aprotic diazotization of a Gewald-like 2-aminothiophene is reported.