Enantioselective, Decarboxylative (3+2)-Cycloaddition of Azomethine Ylides and Chromone-3-Carboxylic Acids.

Herein, we describe the synthesis of a variety of chiral hybrid pyrrolidine-chromanone polycyclic derivatives. A convenient (3+2)-annulation of azomethine ylides with chromone-3-carboxylic acid realized under Brønsted base catalysis produced highly functionalized products in high yields with good stereoselectivities through asymmetric, intermolecular, and decarboxylative (3+2)-cyclization.