Asymmetric cycloadditions of palladium-polarized aza-o-xylylenes.

Vinyl benzoxazinanones undergo highly enantioselective decarboxylative cycloadditions with electron-deficient olefins in the presence of palladium catalysts. Palladium induces the decarboxylation of the parent benzoxazinanones under mild conditions to produce an intermediate that can be described as a polarized aza-o-xylylene. These intermediates undergo a formal [4 + 2] cycloaddition with good Michael acceptors to produce highly substituted hydroquinolines with excellent regio-, diastereo-, and enantioselectivities.