反应详情

At 0° C., to a solution of 71a (60 mg) in 5 mL CH2Cl2 was added a solution of HCl in 1,4-dioxane (4 N, 2 mL) and stirred at RT for overnight. The precipitate (2s-HCl) was filtered and washed with diethyl ether. Yield: 81.3%. 1H NMR (500 MHz, CDCl3) δ 10.0 (s, 1H), 8.29 (s, 1H), 8.05 (d, 2H, J=6.0 Hz), 7.74 (s, 2H), 7.72 (d, 2H, J=6.0 Hz), 4.15 (s, 2H), 3.99 (s, 3H), 3.96 (s, 6H), 2.61 (s, 3H). MS (ESI) m/z 399.1 (M+H)+.

1. filtrationThe precipitate (2s-HCl) was filtered
2. washwashed with diethyl ether