Fig. 2: Catalytic synthesis of C3-substituted morpholines/morpholin-2-ones.

A In(III)-catalyzed synthesis of morpholine containing an aza-quaternary center by Carreira. B Aza-benzilic ester rearrangement for the construction of aza-tertiary center of morpholinone. C Construction of morpholinone bearing aza-quaternary center by ZnCl2 catalysis (this work).