Synthesis of Novel Vicinal Coumarin-and Oxindole-Functionalized Dispiropyrrolidines and Dispiropyrrolizidinesvia [3+2]-Cycloaddition Reactions

The adducts generated from isatin and sarcosine or L-proline undergo [3 + 2] cycloaddition with (E)-arylidene-3,4-dihydrocoumarins to yield polycyclic products with complete diastereoselectivity.