Regio- and stereoselective synthesis of novel spiropyrrolidines through 1,3-dipolar cycloaddition reactions of azomethine ylides and 2-styrylquinazolin-4(3H)-ones

Efficient regio- and stereoselective synthesis of novel of spiropyrrolidines was achieved through 1,3-dipolar cycloaddition reaction of 2-styrylquinazolin-4(3H)-ones with azomethine ylides generated in situ from decarboxylative coupling of L-proline and isatin. The present approach offers the advantages of a clean and simple methodology, high atom economy, short reaction time, wide substrate scope, and a high yielding protocol for spiropyrrolidines.