Synthesis of 2,3-disubstituted thiophens via metalated acetylenes and allenes

Abstract

2,3-Disubstituted thiophen derivatives have been obtained in reasonable yields by treating 2-alkyne- and allene derivatives with butyllithium and potassium t-butoxide in tetrahydrofuran, adding carbon disulfide to the organometallic intermediate and then successively adding t-butyl alcohol, hexamethyl-phosphoric triamide and methyl iodide.