Patent ID: 8765668

Claim:
A process for an enrichment of one enantiomer of the compound of the formula (IX) wherein the stereogenic center marked with an * either can be in (R)- or (S)-configuration at marked center; X is halogen selected from fluoro, chloro, or bromo, same or different, and n is 1-4, Q is N, CH, C—CF 3 , or C-phenyl, and R 10 is H, C 1 -C 4 -alkyl or fluorinated C 1 -C 2 -alkyl, the process comprising providing a mixture of enantiomers of the compound of formula (IX); subjecting the mixture of enantomers to chromatography so as to separate the enantiomers; collecting the separated enantiomers; subjecting a separated undesired enantiomer to a racemisation reaction wherein the racemisation of the separated undesired enantiomer is carried out in the presence of acid, base or a mixture of acid and base, wherein the acid is in molar excess in respect to the base and further wherein the acid is selected from C1-C4 carboxylic acids and the base is selected from tri-C1-C6 alkylamines.