Simple and Efficient Synthesis of Substituted 2-Pyrrolidinones, 2-Pyrrolones, and Pyrrolidines from Enaminones of Baylis−Hillman Derivatives of 3-Isoxazolecarbaldehydes^§,‡

The enaminones, generated from derivatives of appropriately substituted Baylis−Hillman adducts of 3-isoxazolecarbaldehydes, undergo intramolecular ring-closure reactions to afford substituted 2-pyrrolidinones, 1,5-dihydro-2-pyrrolones, and N-substituted pyrrolidines in good yields.