| 摘要 |
PURPOSE:To obtain an optically active substance useful as a medicine, agricultural chemical, perfume, liquid crystal or an intermediate therefor in high asymmetric yield, by irradiating an achiral starting material in a chiral crystal state with light. CONSTITUTION:An achiral starting material (e.g. alkylamide of an alpha-keto- carboxylic acid) in a chiral crystal state is irradiated with light to afford the aimed optically active substance (e.g. beta-lactam) in >=50% e.e. optical purity. The chiral crystal state is produced by combining the starting material with an optically active compound (preferably a compound expressed by the formula) and crystallizing the starting material or irradiating the starting material with light without using any optically active compound to provide crystals, having a crystal form deficient in plane symmetry and convertible into an optically active cyclization product and consisting of only one antipode thereof. |
