Process for preparing optically pure active compounds

A process for preparing an optically pure PPI having a sulfinyl structure selected from the group consisting of (S)-5-methoxy-2-[(4-methoxy-3,5-dimethyl-2-pyridinyl)methylsulphinyl]-1H-benzimidazole, (S)-2-[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl)methylsulphinyl]-1H-benzimidazole, (S)-2-{[4-[3-methoxypropoxy)-3-methylpyridin-2-yl]methylsulphinyl}-1H-benzimidazole, (S)-5-methoxy-2-((4-methoxy-3,5-dimethyl-2-pyridylmethyl)sulphinyl}-1H--imidazo(4,5-b)pyridine, (R)-5-methoxy-2-[(4-methoxy-3,5-dimethyl-2-pyridinyl)methylsulphinyl]-1H-benzimidazole, (R)-5-difluoromethoxy-2-((3,4-dimethoxy-2-pyridinyl)methylsulphinyl[-1H-benzimidazole, (R)-2-[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl)methylsulphinyl]-1H-benzimidazole, (R)-2-{(4-(3-methoxypropoxy)-3-methylpyridin-2-yl)methylsulphinyl}-1H-benzimidazole and (R)-5-methoxy-2-((4-methoxy-3,5-dimethyl-2-pyridylmethyl)sulphinyl)-1H-imidazol(4,5-b)pyridine in enantiomerically pure or enantiomerically enriched form comprising oxidizing a corresponding sulfide of said proton pump inhibitor (PPI) wherein the oxidation is carried out in the presence of a chiral zirconium complex.

A process for preparing an optically pure proton pump inhibitor (PPI) having a sulfinyl structure (S)-5-methoxy-2-[(4-methoxy-3,5-dimethyl-2-pyridinyl)methylsulphinyl]-1H-benzimidazole, in enantiomerically pure or enantiomerically enriched form comprising oxidizing a corresponding sulfide of said PPI, wherein the oxidation is carried out in the presence of a chiral zirconium complex or a chiral hafnium complex.