Synthesis of imidazo[1,2-a]pyridine derivatives and Zolimidine via a novel zinc/iodine-catalyzed Ortoleva-King type protocol

Abstract

Imidazo[1,2-a]pyridines belong to a class of heterocyclic motifs possessing unique structural and pharmacological properties making them an interesting and promising domain in the fields of drug discovery and medicinal chemistry. These molecules have witnessed many fascinating strategies for their synthesis due to their versatile attribute. We herein put forward, the first zinc-catalyzed Ortoleva-King type reaction for the synthesis of imidazo[1,2-a]pyridines. The reaction design involves the use of easily accessible and economical nano zinc oxide and molecular iodine as the catalytic dyad. Diverse acetophenones and 2-aminopyridines were used as substrates and the reaction was observed to be general fostering moderate to good results. Furthermore, we could synthesize Zolimidine (a gastro-protectant) via this one-pot reaction design as a validation to its efficacy in the pharmaceutical world.

Keywords

• Imidazo[1,2-a]pyridines
• Ortoleva-King reaction
• Nano zinc oxide
• 2-Aminopyridines
• Zolimidine