Ionic Liquid Promoted Facile One-Pot Synthesis of 1-Pyridylimidazo[1,5-a]pyridines from Dipyridylketone and Aryl Aldehydes

Abstract

A highly efficient one-pot methodology has been developed to synthesize a class of substituted 1-pyridylimidazo[1,5-a]pyridines, using Bronsted acidic ionic liquid 1-butylimidazolium tetrafluoroborate, [Hbim]BF₄ in excellent isolated yields in the absence of any catalyst. The methodology is characterized by simple work-up procedures along with efficient recovery and recycling of the ionic liquid, which acts as a reaction medium as well as a promoter.

imidazo[1,5-a]pyridines - aldehyde - heterocycles - ionic liquids - ammonium acetate

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