Optical Activation of α-Substituted Carbonyl Compounds by Asymmetric Transformation

Immonium salts of enamines of racemic α-substituted carbonyl compounds with optically active acids gave, on hydrolysis with water, the corresponding optically active carbonyl compounds. Several reaction conditions were examined and a plausible reaction mechanism, an asymmetric transformation, was proposed. Rates of racemization for the (+)-α-pheiiylpropionaldehyde were also determined.