Microwave assisted one-pot synthesis of pyrrolo[2,1-b]thiazol-6-ones from α-aroyl ketene-N,S-acetals†

Abstract

α-Aroyl ketene-N,S-acetals 3 prepared by the reaction of β-oxothioamides 1 with phenacyl bromides 2, underwent sequential cyclizations under microwave irradiation to afford pyrrolo[2,1-b]thiazol-6-ones 6 in good yields. A double cyclization takes place regioselectively in one pot and variety of functionalized pyrrolo[2,1-b]thiazol-6-ones were prepared by this protocol. The mode of cyclization under microwave condition is different from conventional heating. J. Heterocyclic Chem., (2010).