Abnormal Nucleophilic Reaction of Ethyl Crotonate: An Easy Way to Form Novel Imidazo[1,5-a] pyridine derivatives

An abnormal intramolecular nucleophilic reaction of α-carbon of α,β-unsaturated ester was discovered and the reaction makes it very easy to form imidazo1,5-a]pyridine derivatives. The mechanism of the reaction was discussed.