反应详情

Dimethyl 7-Benzyloxy-3-(4-benzyloxyphenyl)-4-ethylpyrrolo[2,1,5-cd]indolizine-1,2-dicarboxylate (1.0 g, 1.7 mmol) was dissolved in 100 ml of methanol. Potassium hydroxide (3.37 g, 60 mmol) and 2 ml of water was added and the mixture was heated to reflux for 4 days. The reaction mixture was allowed to cool to room temperature and acidified with concentrated hydrochloric acid until pH=1. The resulting precipitate was filtered off, and washed with water and ethanol. This gave 0.89 g (96%) of 7-benzyloxy-3-(4-benzyloxyphenyl)-4-ethylpyrrolo[2,1,5-cd]indolizine-1,2-dicarboxylic acid as yellow crystals. M.p. 151-161° C. MS(SP): m/z 545 (M+). 1H-NMR (DMSO-d6, 200 MHz) δ: 1.32 (t, 3H); 3.02 (q, 2H); 5.18 (s, 2H); 5.52 (s, 2H); 7.15 (d, 2H); 7.29-7.56 (m, 10H); 7.61-7.71 (m, 3H); 8.18 (d, 1H).

1. temperaturethe mixture was heated
2. temperatureto reflux for 4 days
3. filtrationThe resulting precipitate was filtered off
4. washwashed with water and ethanol