反应详情

温度

0 °C

Crude tert-butyl (S)-3-cyclopentyl-1-hydroxypropan-2-ylcarbamate from the previous step was dissolved in CH2Cl2 (30 mL). Et3N (3.2 mL, 24.3 mmol) was added and the mixture was cooled to 0° C. A solution of MsCl (1.1 g, 9.7 mmol) in CH2Cl2 (10 mL) added dropwise. After stirring for an additional 2 h, water (30 mL) was added and the mixture was extracted with CH2Cl2 (2×30 mL). The combined organic layers were washed with brine, dried over MgSO4, and evaporated to give crude tert-butyl (S)-3-cyclopentyl-1-(methanesulfonyloxy)propan-2-ylcarbamate that was used in the next step without further purification. 1H NMR (CDCl3, 400 MHz) δ 1.09 (m, 2H), 1.46 (s, 9H), 1.50 (m, 3H), 1.60 (m, 3H), 1.81 (m, 3H), 3.02 (s, 3H), 3.86 (m, 1H), 4.17 (dd, J=10, 4 Hz, 1H), 4.27 (dd, J=10, 3.2 Hz, 1H), 4.59 (brs, 1H).

1. extractionthe mixture was extracted with CH2Cl2 (2×30 mL)
2. washThe combined organic layers were washed with brine
3. dry with materialdried over MgSO4
4. customevaporated