Facile Approach to Optically Active α-Alkylidene-β-amino Esters by Thermal Overman Rearrangement

A convenient synthetic method for enantioenriched (E)-α-alkylidene-β-amino esters has been developed through thermal Overman rearrangement. Readily accessible (Z)-β-branched Morita−Baylis−Hillman esters serve as chiral pool precursors. Thermal rearrangement proceeded through a concerted pseudopericyclic transition state to produce (E)-stereoselective products. We expanded the synthetic utilities of α-alkylidene-β-amino esters via preparation of α-alkylidene-β-lactam derivatives.