| abstract |
The present invention relates to a process for the preparation of substantially pure N-((S)-(-)-α-methylbenzyl)-3-(S)-(4-fluorophenyl)-1,4-oxazin-2-one hydrochloride, which comprises selectively crystallising the (S,S)-diastereomer as the hydrochloride salt from a mixture of the (S,R)- and (S,S)-diastereomers in an organic solvent, and collecting the resultant crystalline product. |