Access to Imidazo[1,2-a]pyridines via Annulation of α-Keto Vinyl Azides and 2-Aminopyridines.

An unprecedented annulation of vinyl azides and 2-aminopyridines is achieved under thermal conditions to give imidazo[1,2-a]pyridines in excellent yields. A one-pot synthesis of Groebke imdidazo[1,2-α]pyridines is also presented [e.g. synthesis of compound (VI)]. [ABSTRACT FROM AUTHOR]