Ethyl Acetate → 2-(((3-methyl-4-(2-(2-propyl-1,3-dioxolan-2-yl)ethoxy)pyridin-2-yl)methyl)sulfinyl)-1H-benzimidazole

Participants

Reaction Steps

The 2-(((3-methyl-4-(2-(2-propyl-1,3-dioxolan-2-yl)ethoxy)pyridin-2-yl)methyl)thio)-1H-benzimidazole (482 mg, 1.17 mmol) obtained in the step (3f) was dissolved in a solvent mixture of toluene (30 ml) and methanol (3 ml). The mixture was cooled in a nitrogen atmosphere. To this mixture, a methanol solution (1.3 ml) of 3-chloroperbenzoic acid (311 mg, 1.17 mmol as the content was regarded as 65%) was added at an inner temperature of below −70° C. and stirred below −60° C. for 2 hours. To the reaction mixture, an aqueous solution of sodium hydrogen carbonate and ethyl acetate were added. The organic layer was separated and washed with a saturated saline solution, dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure. The residue was dissolved in methylene chloride and subjected to silica gel column chromatography using NH silica gel (elution solvent: methylene chloride/methanol=1/0→100/1→100/5) to obtain the title compound (323 mg, yield: 64.3%).

Provenance & Evidence