Synthesis of Functionalized Indolizines by Lewis Acid-Mediated Cyclocondensation of 3-(Pyridin-2-yl)-propiolates with Enones

Functionalized indolizines were prepared by Lewis acid-catalyzed cyclizations of 3-(pyridin-2-yl)-propiolates with enones. This new type of reaction provides a convenient and regioselective approach to ester-substituted indolizine derivatives which are not readily available by other methods. Based on density function theory (DFT) calculations, a mechanism of the reaction has been suggested.