反应详情

温度

-10 °C

At -40° C., Et3N (triethylamine) (1.60 mL, 11.5 mmol) and methanesulfonyl chloride (750 μl, 9.69 mmol) were added to a solution of the alcohol of Step 6 (7.39 mmol) in 74 mL of CH2Cl2 and the mixture was stirred at -40° C. for an hour and at -10° C. for 45 minutes. Saturated aq NaHCO3 was then added and the mesylate was extracted with CH2Cl2, dried over Na2SO4 and concentrated. To this mesylate in 150 mL of anhydrous CH3CN, ethyl 3-mercapto-2-methylpropanoate (Example 4, Step 6; 2.20 mL, approx. 15 mmol) and Cs2CO3 (7.57 g, 23.2 mmol) were added and the mixture was stirred under a stream of N2 for 2 hours. 25% Aq NH4OAc was then added and the title product was extracted with EtOAc, dried over Na2SO4 and purified by flash chromatography on silica with EtOAc:toluene.

1. extractionthe mesylate was extracted with CH2Cl2
2. dry with materialdried over Na2SO4
3. concentrationconcentrated
4. extractionthe title product was extracted with EtOAc
5. dry with materialdried over Na2SO4
6. custompurified by flash chromatography on silica with EtOAc