反应详情

11.0 g of 2-acetoxymethyl-3-methyl-4-propoxy-pyridine was dissolved in chloroform, and 30 g (4 eq.) of thionyl chloride was added. The mixture was heated to reflux for one hour and then concentrated, and a residue resulting therefrom was dissolved in methanol. The solution was added in advance to 8.7 g (1 eq.) of 2-mercaptobenzimidazole, 73 mL of a 28% sodium methoxide solution, and 300 mL of methanol, and the mixture was heated to reflux for one hour. Methanol was distilled off, ice was added to the residue, and the mixture was extracted with ethyl acetate. The ethyl acetate layer was dried over anhydrous magnesium sulfate. Subsequently, the ethyl acetate solution was concentrated to dryness, and the resulting residue was purified by silica gel column chromatography, and then was concentrated to dryness, to obtain 15.5 g of yellow crystals. The yellow crystals were recrystallized from ethyl acetate, to obtain 6.3 g of colorless crystals. Total yield 17% (purity by HPLC: 98.1%).

1. temperatureThe mixture was heated
2. temperatureto reflux for one hour
3. concentrationconcentrated
4. customa residue resulting
5. temperaturethe mixture was heated
6. temperatureto reflux for one hour
7. distillationMethanol was distilled off
8. additionice was added to the residue
9. extractionthe mixture was extracted with ethyl acetate
10. dry with materialThe ethyl acetate layer was dried over anhydrous magnesium sulfate
11. concentrationSubsequently, the ethyl acetate solution was concentrated to dryness
12. customthe resulting residue was purified by silica gel column chromatography
13. concentrationwas concentrated to dryness