Fragmentation of Optically Active (1‐Phenylethyl)‐ and (1‐Naphthylethyl)ureas in Refluxing Alcohols: Easy Preparation of Optically Active Amines of High Optical Purity

Abstract (1‐Phenylethyl)‐ and (1‐naphthylethyl)ureas, obtained in the reaction of racemic amines with optically pure isocyanates, are separated and then decomposed in refluxing alcohols, to afford optically pure secondary amines and optically pure alkyl carbamates in quantitative yields. The scope of this fragmentation for the resolution of racemic mixtures of amines is illustrated by several examples of biologically important compounds. Carbamates obtained by this fragmentation can readily be recycled.