A process for preparing a third compound stereo-selectively which process comprises reacting a substrate comprising a first enantiomeric compound with a racemisation catalyst to give a second enantiomeric compound, and concurrently reacting the second enantiomeric compound in the presence of a biological catalyst to give the third compound, wherein the process is performed in a solvent comprising at least one (hydro) fluorocarbon. The biological catalyst is preferably an enzyme. The substrate preferably comprises a racemate of the first and second enantiomeric compounds. The second enantiomeric compound may be reacted with a reagent, such as acyl donor, to form the third compound in the presence of the biological catalyst.
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