Catalytic Asymmetric Synthesis of Atropisomeric Nitrones: Versatile Intermediate for Axially Chiral Biaryls.

A Cu-catalyzed asymmetric ring-opening reaction of five-membered diaryliodonium salts and oximes is introduced. The reactions undergo selective N-arylation of oximes and provide an efficient protocol for the synthesis of atropisomeric nitrones. The optically active nitrones, serving as versatile intermediates, were converted to diversely functionalized axially chiral aniline derivatives and N-heterocycles.