Asymmetric aziridination of 1,3-dienes catalyzed by bisoxazoline-copper complexes.

The asymmetric aziridination of 1,3-dienes catalyzed by bisoxazoline-CuOTf complexes with PhI=NTs as a nitrene precursor has been achieved in moderate yields with up to >99:1 regioselectivity, up to >99% diastereoselectivity, and up to 80% enantioselectivity. alpha,beta,gamma,delta-Unsaturated ketones usually produced cis-gamma,delta-aziridinated products, while 1,4-diphenyl-1,3-butadiene afforded both of cis- and trans-aziridine derivatives as major products by the use of different bisoxazoline ligands. The configuration of cis-aziridine derivatives was proposed on the basis of the reaction mechanism.