| Abstract: | Gibbs energy of racemate formation, binary melting point diagram, and ternary solubility diagram suggested that 4-piperidinium hydrogen (RS)-phenylsuccinate [(RS)-4-MP salt] exists in a conglomerate. Appropriate conditions were explored on the basis of free energy of critical nucleation in a supersaturated solution to resolve efficiently (RS)-4-MP salt by preferential crystallization. Successive preferential crystallization of (RS)-4-MP salt in ethanol at 20°C gave (R)- and (S)-4-MP salts of 90–94% optical purities. Optically pure (R)- and (S)-phenylsuccinic acids were obtained by recrystallization of the (R)- and (S)-4-MP salts, followed by treatment of the salts purified with hydrochloric acid. © 1994 Wiley-Liss, Inc. |
