反应详情

To a solution of tetrahydrothiophene-3-carboxylic acid 1,1-dioxide (Enamine, 1 g, 6.1 mmol) in THF (20 mL) at −10° C. was added 4-methylmorpholine (0.67 mL, 6.1 mmol). The mixture was stirred for 1 min then ethyl chloroformate (0.58 mL, 6.1 mmol) was added dropwise. This mixture was stirred at −10° C. for 15 min then was filtered through Celite and the filtrated was added dropwise via syringe to a mixture of NaBH4 (0.52 g, 13.7 mmol) in water (10 mL) at 5° C. The ice-bath was removed after the addition was complete and the mixture was stirred at ambient temperature for 2 h. The mixture was quenched with saturated, aqueous NH4Cl (10 mL) and diluted with EtOAc (10 mL). The layers were separated and the aqueous layer was extracted with EtOAc (3×5 mL). The combined organics were dried over anhydrous Na2SO4, filtered and concentrated under reduced pressure to give the title compound (0.22 g) which was used without further purification. MS (DCI/NH3) m/z 168 (M+NH4)+.

1. stirringThis mixture was stirred at −10° C. for 15 min
2. filtrationthen was filtered through Celite
3. customThe ice-bath was removed
4. additionafter the addition
5. stirringthe mixture was stirred at ambient temperature for 2 h
6. customThe mixture was quenched with saturated, aqueous NH4Cl (10 mL)
7. additiondiluted with EtOAc (10 mL)
8. customThe layers were separated
9. extractionthe aqueous layer was extracted with EtOAc (3×5 mL)
10. dry with materialThe combined organics were dried over anhydrous Na2SO4
11. filtrationfiltered
12. concentrationconcentrated under reduced pressure