Patent ID: 8362258

Claim:
A composition of matter comprising a sulfoxide, 5-methoxy-2-((4-methoxy-3,5-dimethyl-2-pyridinyl)methyl)methylsulfinyl)-1H-benzimidazole, said sulfoxide having R and S enantiomers and further comprising a compound selected from the group consisting of a transition metal catalyst and an oxygen source wherein said transition metal catalyst is a transition metal complex wherein the transition metal of said transition metal complex is selected from the group consisting of Cr, W, Ru, Rh, Pd, Ir and Pt and wherein said oxygen source is selected from the group consisting of peracids, hydrogen peroxide, dimethyldioxirane and molecular oxygen; wherein the thioether is oxidized to a sulfoxide and has one of either the R and S enantiomers in an enantiomeric excess.