Process for optical resolution of 1,2-diol derivatives

This invention provides a process for producing an optically active 1,2-diol derivative by optical resolution. The optically active 1,2-diol derivative of the formula (I) which is capable of utilizing as an intermediate of fungicidal optically-active azole derivatives can be produced by esterifying a 1,2-diol derivative of the formula (I) as a substrate with a carboxylic acid derivative of the formula (II) as a reagent in the presence of a lipase as a catalyst. (I) R3COOR4 (II) wherein R1 is C1-C5 alkyl group, C3-C7 cycloalkyl group or C1-C5 haloalkyl group, R2 is C1-C3 alkyl group substituted by a phenyl group which may have one or two halogen atoms and/or C1-C4 alkyl groups, C2-C3 alkenyl group substituted by a phenyl group which may have one or two halogen atoms and/or C1-C4 alkyl groups, or C1-C3 alkyl group substituted by a phenoxy group which may have one or two halogen atoms and/or C1-C4 alkyl groups, R3 is C1-C10 alkyl group or aryl group, and R4 is hydrogen atom, C1-C5 alkyl group, C2-C4 alkenyl group or COR3.