Synthesis one pot of imidazo[1,2-a]pyridines via Groebke-Blackburn-Bienaymé reaction-CuAAC assisted by MW

Nitrogen heterocycles are present in natural products and synthetic drugs, and represent some of the most important synthetic targets due to their numerous and valuable applications in several fields, in particular bis-heterocyclic compounds containing imidazo[1,2-a]pyridines (IMPs) are privileged heterocyclic drug scaffolds due to their potential applications.

The isocyanide based multicomponent reactions (I-MCR) are greener alternative and one of the most efficient synthetic strategies to synthesize IMPs, for example the Groebke-Blackburn-Bienaymé reaction (GBBR) allow the synthesis one pot of imidazo[1,2-a]pyridines.

On the other hand 1,2,3-triazole scaffolds are biososteres of the trans amide bond and they are of great interest in the design of novel privileged heterocycles with potential applications in medicinal chemistry, its incorporation in bioactive molecules provides advantages such as resistance to cleavage mediated by proteases and improved stability, in this context the CuAAC reaction is the most efficient approach to synthesize 1,4-disustituted-1,2,3-triazoles. The use of alternative energy source such as microwave irradiation play a key role in multicomponent reaction allowing an efficient temperature increase by the effect of dielectric heating allowing decrease of reaction time with better yields.

Herein we described a novel methodology one pot synthesis of IMPs by the GBBR-CuAAC strategy assisted by microwave irradiation.