Organocatalytic Enantioselective Cross-Dehydrogenative Coupling of N-Carbamoyl Cyclic Amines with Aldehydes.

The existing catalytic enantioselective cross-dehydrogenative coupling of cyclic amines predominantly focused on reactive N-aryl tetrahydroisoquinolines, which typically suffered from limited substrate generality and synthetic utility, and required the use of metal catalyst. Herein, a metal-free catalytic enantioselective cross-dehydrogenative coupling of N-carbamoyl cyclic amines and aldehydes has been reported for the first time. Employing an easily installed and functionalized acyl protecting group rather than the widely adopted aryl moiety endows the enantioselective process with better substrate generality and broader synthetic utility.