Stereoconvergent Chiral Inductive Diastereodivergent Sulfonamidation of Diastereomixtures of Diarylmethanols with Sulfonylamine Catalyzed by Lewis Acids.

Diastereodivergent sulfonamidation of diastereomixtures of diarylmethanols bearing a chiral auxiliary using a sulfonylamine was achieved by use of SnCl2 and FeCl3 as the Lewis acid catalysts in nitromethane under mild reaction conditions. Both reaction conditions were applicable to a broad substrate scope, irrespective of the substituents on the aromatic ring of the substrates. The nosyl group and the chiral auxiliary were easily deprotected under the general conditions without any erosion of chirality.