Scandium-bipyridine-catalyzed enantioselective aminolysis of meso-epoxides

The scandium-bipyridine-catalyzed enantioselective addition of anilines and O-alkyl hydroxylamines to meso-epoxides has been optimized and extended to a broad range of epoxides and amines. Whereas aromatic meso-epoxides generally furnished the corresponding 1.2-amino alcohols in excellent enantioselectivities, aliphatic mesoepoxides only gave rise to moderate enantioselectivities in the aminolysis. The catalyst loading may be lowered to just 5 mol % with only marginal effects on yield and enantioselectivity. A strong positive nonlinear effect has been observed, pointing to aggregation phenomena of the catalyst.