Catalyst-Free Friedel–Crafts Alkylation of Imidazo[1,2-α]pyridines

Abstract

A catalyst-free Friedel–Crafts alkylation of imidazo[1,2-α]pyridines with β-nitrostyrenes was developed. Electron-donating and electron-withdrawing functional groups at various aromatic positions were well tolerated under our optimized conditions. This method provides an efficient and environmentally benign route to synthesize imidazo[1,2-α]pyridine-nitroalkane derivatives in moderate to excellent yields.

Key words

imidazo[1,2-α]pyridine - catalyst-free - Friedel–Crafts alkylation

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