反应详情

温度

-50 °C

To a toluene (30 ml)/methanol (3 ml) solution of the 2-(((4-(5,9-dioxaspiro[3.5]non-7-yloxy)-3-methylpyridin-2-yl)methyl)thio)-1H-benzimidazole (290 mg, 0.73 mmol) obtained in the step (9h), a toluene/methanol (10:1) solution of 3-chloroperbenzoic acid (174 mg, 0.65 mmol as the content was regarded as 65%) was added at −70° C. in a nitrogen atmosphere. After the mixture was stirred at −50° C. for one hour, a saturated aqueous solution of sodium hydrogen carbonate was added. After the mixture was warmed to room temperature, the mixture was extracted with ethyl acetate twice. Organic layers were combined and dried over anhydrous sodium sulfate, filtered and concentrated. The residue was purified by silica gel column chromatography (NH silica gel, elution solvent: ethyl acetate, ethyl acetate/methanol=9/1). Fractions containing the title compound was collected by use of ethyl acetate and concentrated. After diethyl ether was added to the residue, the solvent was distilled off to obtain the title compound (230 mg, yield: 76.2%) as a white solid.

1. additionwas added at −70° C. in a nitrogen atmosphere
2. temperatureAfter the mixture was warmed to room temperature
3. extractionthe mixture was extracted with ethyl acetate twice
4. dry with materialdried over anhydrous sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated
7. customThe residue was purified by silica gel column chromatography (NH silica gel, elution solvent: ethyl acetate, ethyl acetate/methanol=9/1)
8. additionFractions containing the title compound
9. customwas collected by use of ethyl acetate
10. concentrationconcentrated
11. additionAfter diethyl ether was added to the residue
12. distillationthe solvent was distilled off