反应详情

To a solution of anhydride (286) (2.80 g, 7.42 mmol) prepared as described in example 296 in glacial acetic acid (70 mL) was added 2,4-dimethoxybenzylamine (1.67 mL, 11.1 mmol). The resulting solution was heated at reflux for 6 hours before being partially concentrated under reduced pressure and diluted with water to precipitate an orange solid, which was collected by filtration, washed with water and dried in vacuo. This crude material was then dissolved in p-dioxane and aromatized according to the procedure for example 79, before being chromatographed on silica eluting with ethyl acetate/hexane (1:1). Crystallisation from methanol then gave carbazole (287) (1.46 g, 37%) as a yellow powder, mp 224–226° C. 1H NMR δ [(CD3)2SO] 12.02 (br s, 1H), 8.45 (d, J=2.6 Hz, 1H), 7.62 (s, 1H), 7.58 (m, 2H), 7.53–7.42 (m, 3H), 7.25 (dd, J=8.8, 2.6 Hz, 1H), 6.95 (d, J=8.4 Hz, 1H), 6.57 (d, J=2.3 Hz, 1H), 6.45 (dd, J=8.4, 2.3 Hz, 1H), 4.68 (s, 2H), 3.88 (s, 3H), 3.80 (s, 3H), 3.72 (s, 3H). Found: C, 68.22; H, 4.37; N, 5.29. C30H23ClN2O5 requires: C, 68.38; H, 4.40; N, 5.32.

1. temperatureThe resulting solution was heated
2. temperatureat reflux for 6 hours
3. concentrationbefore being partially concentrated under reduced pressure
4. additiondiluted with water
5. customto precipitate an orange solid, which
6. filtrationwas collected by filtration
7. washwashed with water
8. customdried in vacuo
9. dissolutionThis crude material was then dissolved in p-dioxane
10. custombefore being chromatographed on silica eluting with ethyl acetate/hexane (1:1)
11. customCrystallisation from methanol