反应详情

温度

0 °C

To the title compound of step 3 (19.0 g, 82.60 mmol) in dry CH2Cl2 (200 mL) at 0° C., m-CPBA (42.62 g, 247.80 mmol) was added over 15 min. The mixture was stirred at 0° C. for 30 min and at r.t. overnight. Sat.aq. Na2SO3 (100 mL) was added and CH2Cl2 extractive work up was carried out. Trituration with MTBE (300 mL) gave the title compound (17 g, 78.3% yield) as a white solid. 1H NMR (CDCl3, 400 MHz) δ 8.37 (s, 1H), 4.13 (d, J=6.8 Hz, 2H), 3.33 (s, 3H), 1.39-1.35 (m, 1H), 0.79-0.74 (m, 2H), 0.49-0.45 (m, 2H). LCMS: 263.0 (M+1)+