Divergent synthesis of N-heterocycles by Pd-catalyzed controllable cyclization of vinylethylene carbonates.

Here, we report a palladium-catalyzed controllable cyclization of vinyl ethylene carbonates that proceeds through formal migration [2+3] and [5+2] cycloadditions, respectively, under mild conditions. The transformation described here affords a series of synthetically versatile 5,7-membered N-heterocycles which are found in natural products and pharmaceuticals with biological and medicinal properties.