Patent ID: 8263769

Claim:
A process for preparing voriconazole of formula (I), which comprises the steps of: a) subjecting the compound of formula (IV) to Reformatsky-type coupling reaction with a compound of formula (V) to obtain a compound of formula (III) which is a (2R,3S)/(2S,3R)-enantiomeric pair; b) removing the thiol derivative from the compound of formula (III) to obtain the racemic voriconazole of formula (II); and c) isolating the compound of formula (II) by way of optical resolution using an optically active acid: wherein, R is C 1 -C 4 alkyl, benzothiazolyl, benzoxazolyl, imidazolyl, 1-methylimidazolyl, thiazolyl, pyridyl, pyrimidyl, phenyl, or phenyl having one or two substituents selected from the group consisting of halogen, nitro and methoxy.