One-Pot Regioselective Synthesis of 3-Benzylthiazolo[3,2-a]indoles by Sequential Sonogashira Coupling Followed by Triethylamine-Induced Cyclization

A number of 2-(prop-2-ynylthio)-1H-indoles have been utilized for the synthesis of 3-benzylthiazolo[3,2-a]indoles by Sonogashira acetylide-coupling followed by triethylamine-induced regioselective cyclization in a one-pot operation. The cyclization is dependent on the nature of the substituents on the phenyl ring of the substrates.