反应详情

To a solution of 5-bromo-7-nitro-N-ethoxalylindoline (2.0 g, 5.83 mmol) in a mixture of THF (50 mL), water (10 mL), and acetic acid (10 mL) was added aqueous 20% titanium trichloride (31 mL, 40.8 mmol) and the mixture was stirred for 4 h at room temperature. The precipitates formed were collected by filtration, washed with diluted aqueous hydrochloric acid and then distilled water, and dried in vacuo to give 772 mg of the title compound (50%): mp>300° C.; 1H NMR (270 MHz, DMSO-d6) δ11.91 (bs, 1H), 7.21 (d, 1H, J=1 Hz), 7.02 (d, 1H, J=1 Hz), 4.22 (t, 2H, J=7 Hz), 3.32 (t, 2H, J=7 Hz).

1. customThe precipitates formed
2. filtrationwere collected by filtration
3. washwashed with diluted aqueous hydrochloric acid
4. dry with materialdistilled water, and dried in vacuo