反应详情

A solution of 4c (1.98 g, 7.36 mmol) in THF (10 mL) and 6 N HCl (20 mL) was stirred for 2 days at room temperature. Chloroform (20 mL) was added to the solution to induce precipitation upon vigorous stirring 15 min. The precipitate was collected by vacuum filtration to give 10b (1.50 g, 85%) as a yellow solid. 1H NMR (400 MHz, D6-DMSO) δ 12.25 (s, 1 H), 7.78 (d, J=8 Hz, 1 H), 7.66 (td, J=8, 1 Hz, 1 H), 7.44 (td, J=8, 1 Hz, 1 H), 7.32 (d, J=8 Hz, 1 H), 3.70 (br s, 1 H), 3.58 (s, 2 H).

1. customprecipitation
2. filtrationThe precipitate was collected by vacuum filtration