Silver-Catalyzed Cyclization of N-(Prop-2-yn-1-yl) pyridin-2-amines

We report herein the silver-catalyzed cycloisomerization of readily available N-(prop-2-yn-1-yl) pyridine-2-amines as a new and practical method for the synthesis of differently substituted 3-methylimidazo[1,2-a] pyridines. The isomerization reactions proceeded under mild reactions conditions to give good yields and excellent regioselectivity. A DFT-based mechanistic analysis is also reported.