Patent ID: 7511168

Claim:
A process for preparing the compounds of Formula II-2, having an enantiomeric purity higher than 95% enantiomeric excess: wherein Z is â€”OR 1 , â€”N(R 1 ) 2 , or â€”SR 1 , wherein R 1 at each occurrence is independently an alkyl, an alkenyl, an alkynyl, an aryl, or an aralkyl, each of which is unsubstituted or substituted with one or more substituents selected from the group consisting of halogen, alkyl, aryl, alkoxyl, aryloxy, thioalkoxyl, thioaryloxy, alkylamino, arylamino, cyano, alkoxycarbonyl, arylcarbonyl, arylaminocarbonyl, alkylaminocarbonyl, pyridinyl, thiophenyl, furanyl, imidazolyl, morpholinyl, oxazolinyl, piperidinyl, piperazinyl, tetrahydropyranyl, pyrrolidinyl and pyrrolidinonyl; R 2 is a single bond or a C 1-4 -alkylene or â€”CH 2 Oâ€”; and R 3 is a C 1-7 -alkyl or an aryl or an aralkyl, each of which is unsubstituted or substituted by a C 1-4 -alkyl, a halogen or a trihalomethyl; the process comprising the steps of: (1) reacting compounds of Formula IV having an optical purity higher then 90% enantiomeric excess: wherein P 1 is a protecting group for the hydroxyl groups, with a cuprate derived from the compound of Formula V-1, Formula V-2 or Formula V-3, each of which having an optical purity higher then 90% enantiomeric excess: wherein Y is a halogen, R 6 is a lower alkyl, R 2 and R 3 are as defined above, is a single bond or a double bond, and P 2 is a protecting group for the hydroxyl groups; to form a mixture of high optical purity compound of Formula II-1; (2) deprotecting the compound of Formula II-1 to remove P 1 and P 2 in the presence of acids to form a mixture of high optical purity compound of Formula II-2 and its diastereomers; and (3) removing the diastereomers of the compound of Formula II-2.