Solvent-free and efficient synthesis of imidazo[1,2-a]pyridine derivatives via a one-pot three-component reaction

Abstract

A green and highly efficient method for the regioselective synthesis of imidazo[1,2-a]pyridine derivatives has been developed by annulation of heterocyclic ketene aminals (HKAs) and β-oxodithioesters (ODEs) as building blocks with aldehydes under solvent-free conditions using Et₃N as the catalyst. The present green synthesis shows fascinating properties such as high regioselectivity, concise one-pot methodology, short reaction times, easy purification and avoids the use of transition metals. This methodology provides an alternative approach for easy access to highly substituted imidazo[1,2-a]pyridines in good yields.