The application belongs to the technical field of
drug synthesis, and more particularly relates to a preparation method of a high-purity
citalopram S-
diol intermediate. The preparation method comprises the following steps: generating a racemic
citalopram diol intermediate; adding an acid to quench the racemic
citalopram diol intermediate, centrifuging, and concentrating the
evaporation substrate by
evaporation under reduced pressure to obtain an
evaporation substrate; mixing the evaporation substrate with a mixed
solvent, adding a chiral resolving agent, and performing
chiral resolution; after the reaction is completed, cooling, incubation
crystallization, washing and
drying are performed to obtain the citalopram S-diol intermediate. Through optimization of the
chiral resolution process, the racemic citalopram diol intermediate can be directly subjected to
chiral resolution after simple post-treatment, and high-purity and high-optical-purity compound 1b can be directly prepared; meanwhile, a plurality of recrystallization processes can be omitted, the operation is simple, the production efficiency is high, and the cost is low.