Copper- and Chiral Nitroxide-Catalyzed Oxidative Kinetic Resolution of Axially Chiral N -Arylpyrroles.

A readily prepared C 2 -symmetric, α-hydrogen-substituted chiral hydroxylamine serves as a precatalyst to generate a chiral nitroxide in situ . This chiral nitroxide catalyst in combination with a copper co-catalyst functions as an oxidant for an unprecedented enantioselective oxidative kinetic resolution (OKR) of racemic axially chiral N -arylpyrrole alcohols using atmospheric oxygen as an environmentally friendly terminal oxidant. The OKR process provides the axially chiral N -arylpyrroles in er up to 3.5:96.5 and with s factors up to 24.