PROCESS FOR PRODUCING OPTICALLY ACTIVE AZETIDINE-2-CARBOXYLIC ACIDS

摘要

A compound (5) can be produced by preparing a compound (3) by subjecting compound (1) to halogenation with inversion to obtain a compound (2) and hydrolyzing the compound (2), by subjecting a compound (6) to halogenation with inversion to obtain a compound (7) and hydrolyzing the compound (7), or by subjecting a compound (6) to halogenation with inversion to obtain a compound (7), cyclizing the compound (7) into a compound (2) and hydrolyzing the compound (2), cyclizing the compound (3) prepared above, and treating the obtained product with an amino-protective agent. The compound (5) thus produced can be further improved in the optical purity by recrystallization.