Reaction #11225

Reaction equation

carbazole

4-(2-Chlorophenyl)-2-(2,4-dimethoxybenzyl)-9-methoxypyrrolo[3,4-c]carbazole-1,3(2H,6H)-dione

potassium carbonate

allyl bromide

→

carbazole

Yield 57.0%

6-Ally-4-(2-chlorophenyl)-2-(2,4-dimethoxybenzyl)-9-methoxypyrrolo[3,4-c]carbazole-1,3(2H,6H)-dione

Yield 57.0%

Solvents

dimethylformamide

water

ethyl acetate

Conditions

Workup

1. 1
   OtherThe organic phase was dried
2. 2
   Otherthe drying agent was removed
3. 3
   Concentrationthe solution was concentrated to dryness
4. 4
   OtherChromatography on silica eluting with ethyl acetate/hexane (1:2), followed by crystallization from diethyl ether/hexane

Procedure

To a solution of carbazole (287) (150 mg, 0.28 mmol) prepared as described in example 297 in dimethylformamide (10 mL) under nitrogen was added potassium carbonate (0.39 g, 2.80 mmol) and allyl bromide (720L, 0.84 mmol). The resulting suspension was warmed to 90° C. with stirring for 3 hours before being diluted with water and extraction with ethyl acetate. The organic phase was dried, the drying agent was removed and the solution was concentrated to dryness. Chromatography on silica eluting with ethyl acetate/hexane (1:2), followed by crystallization from diethyl ether/hexane gave carbazole (288) (90 mg, 57%) as a yellow powder, mp 171–173° C. 1H NMR δ [(CD3)2SO] 8.51 (d, J=2.6 Hz, 1H), 7.84 (s, 1H), 7.67 (d, J=8.9 Hz, 1H), 7.58 (m, 1H), 7.53–7.46 (m, 3H), 7.32 (dd, J=8.9, 2.6 Hz, 1H), 6.97 (d, J=8.4 Hz, 1H), 6.57 (d, J=2.4 Hz, 1H), 6.45 (dd, J=8.4, 2.4 Hz, 1H), 5.99 (m, 1H), 5.18 (d, J=4.9 Hz, 2H), 5.14 (dd, J=10.3, 1.3 Hz, 1H), 4.99 (dd, J=17.2, 1.3 Hz, 1H), 4.69 (s, 2H), 3.90 (s, 3H), 3.80 (s, 3H), 3.72 (s, 3H). Found: C, 69.97; H, 4.75; N, 5.12. C33H27ClN2O5 requires: C, 69.90; H, 4.80; N, 4.94.

Source