m-Chloroperbenzoic acid → 2-(((4-((2-methoxy-1,3-dioxan-5-yl)methoxy)-3-methylpyridin-2-yl)methyl)sulfinyl)-1H-benzimidazole

Participants

Reaction Steps

To a toluene/methanol (10:1) (20 ml) solution of the 2-(((4-((2-methoxy-1,3-dioxan-5-yl)methoxy)-3-methylpyridin-2-yl)methyl)thio)-1H-benzimidazole (324 mg, 807 μmol) obtained in the step (6d), a toluene/methanol (10:1) (5 ml) solution of 3-chloroperbenzoic acid (193 mg, 726 μmol as the content was regarded as 65%) was added dropwise at −50° C. to −60° C. for 5 minutes in a nitrogen atmosphere. The mixture was stirred for 2 hours in the same conditions. To the reaction mixture, a saturated aqueous solution of sodium hydrogen carbonate was added and the resultant mixture was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated. The residue was purified by silica gel column chromatography (NH silica gel, elution solvent: ethyl acetate/methanol) to obtain the title compound (222 mg, 65.9% yield), which is a cis and trans (1:1) mixture, as a light yellow foam.

Provenance & Evidence