Stereoselective Syntheses of Both Enantiomers of Ketoconazole from (R)- and (S)-Epichlorohydrin

Article abstract of DOI:10.1016/0957-4166(95)00161-H

Stereoselective syntheses of both enantiomers of ketoconazole (1) from commercially available (R)- or (S)-epichlorohydrin has been developed.The key-step of syntheses involves the selective substitution of the methylene chlorine atom by benzoate on a mixture of (2S,4R)-14a and (2R,4R)-15a or of their enentiomers, followed by crystalization of the corresponding cis-benzoates, (2R,4R)-18 or (2S,4S)-18, from which (+)- or (-)-1 were obtained as described for (+/-)-1.The ee's of (+)- and (-)-ketocanazole were determined by HPLC on the CSP Chiracel OD-H.