The copper(i)-catalyzed tandem reaction of o-alkynylphenyl isothiocyanates with isocyanides: a rapid synthesis of 5H-benzo[d]imidazo[5,1-b][1,3]thiazines

Abstract

An efficient route to 5H-benzo[d]imidazo[5,1-b][1,3]thiazines has been developed using the copper(I)-catalyzed tandem reaction of o-alkynylphenyl isothiocyanates with isocyanides in THF with Cs₂CO₃ as base. The present tandem process allows the assembly of a variety of 5H-benzo[d]imidazo[5,1-b][1,3]thiazines in good to excellent yields.