反应详情

温度

25 °C

A suspension of baker's yeast (Saf-Instant yeast, 30 g) in water (700 mL) was treated with sucrose (142 g). The mixture was stirred at 25° C. for 6 h. At this time, 4-hydroxy-5,6-dihydro-2H-thiopyran-3-carboxylic acid methyl ester (4.06 g, 23.31 mmol) was added. The resulting slurry was stirred at 25° C. for 22 h and then was filtered through a pad of celite. The filtrate was extracted with ethyl acetate (5×300 mL). The combined organic extracts were washed with a saturated aqueous sodium chloride solution (1×150 mL), dried over magnesium sulfate, filtered, and concentrated in vacuo. Biotage chromatography (FLASH 40M, Silica, 3/1 hexanes/ethyl acetate) afforded 4(S)-hydroxy-tetrahydro-thiopyran-3(R)-carboxylic acid methyl ester (4.08 g, 99.3%) as a colorless oil: [α]23589=+37.76° (c=2.9, methanol)

1. stirringThe resulting slurry was stirred at 25° C. for 22 h
2. filtrationwas filtered through a pad of celite
3. extractionThe filtrate was extracted with ethyl acetate (5×300 mL)
4. washThe combined organic extracts were washed with a saturated aqueous sodium chloride solution (1×150 mL)
5. dry with materialdried over magnesium sulfate
6. filtrationfiltered
7. concentrationconcentrated in vacuo