Deep eutectic solvent promoted synthesis of structurally diverse hybrid molecules with privileged heterocyclic substructures

Abstract

An efficient and eco-friendly diversity oriented synthetic protocol has been presented to synthesize structurally diverse drug-like small hybrid molecules; indenopyrroloimidazoles, imidazoindoles, chromenopyrroloimidazoles and imidazopyrrlopyrimidines, using deep eutectic solvent (DES), guanidinium chloride and urea, as a sustainable solvent and promoter. The use of DES (guanidinium chloride and urea) as a recyclable and reusable solvent and promoter has been explored for the first time in the synthetic domino protocol involving one-pot, three component reaction of hydantoin, 1,3-diketones and aldehydes with special features of the protocol; high atom-economy, operational simplicity, mild reaction conditions, short reaction time, and high selectivity with excellent yields.