Patent ID: 7582469

Claim:
A method for preparing substantially enantiopure 3-hydroxy carboxylic acids or esters of the formula (III) and/or substantially enantiopure oxetan-2-ones of the formula (IV) comprising the steps of (1) reacting racemic oxetan-2-ones of the general formula (I) with compounds of the general formula (II) in the presence of a lipase from Candida antarctica or Burkholderia plantarii , and (2) separating the resulting products of formulae (III) and (IV) from one another wherein R 1 , R 2 , and R 3 are, independently of one another, H, C 1 to C 10 substituted or unsubstituted alkyl, or substituted or unsubstituted aryl or heteroaryl, with the proviso that R 1 cannot equal R 2 .