反应详情

A solution of 1-benzyl-2-(1-hydroxyethyl)-4-methoxy-6,7,8,9-tetrahydro-1H-benz[g]indole (1.0 g, 3.0 mmol) in tetrahydrofuran (5 mL) was treated with acetic anhydride (0.28 mL, 3.0 mmol), pyridine (0.53 mL, 6.6 mmol), 1,4-cyclohexadiene (3 mL), and 10% palladium-on-carbon (0.5 g) at 70° C. for 7 h. The mixture was cooled to room temperature, stirred for 18 h, heated at 80° C. for 9 h, cooled to room temperature, and stirred for 18 h. Additional portions of 10% palladium-on-carbon (0.5 g) and 1,4-cyclohexadiene (3 mL) were added and the resulting mixture stirred at 80° C. for 9 h. The mixture was cooled to room temperature, filtered, and concentrated in vacuo. The residue was dissolved in 9:1 hexanes/ether and treated with 10% aqueous citric acid (3 mL). The organic layer was filtered through silica gel, which was eluted with hexanes, methylene chloride, and ether. Concentration of the appropriate fractions provided 662 mg (70%) of the title compound as an amber foam. 1H NMR (CDCl3) δ 7.22 (m, 3H), 6.83 (d, J=7 Hz, 2H), 6.42 (s, 1H), 6.25 (s, 1H), 5.54 (s, 2H), 3.95 (s, 3H), 2.96 (m, 2H), 2.85 (m, 2H), 2.55 (q, J=6 Hz, 2H), 1.70 (m, 4H), 1.28 (t, J=6 Hz, 3H); MS ES+ m/e 320 (p+1).

1. temperatureheated at 80° C. for 9 h
2. temperaturecooled to room temperature
3. stirringstirred for 18 h
4. stirringthe resulting mixture stirred at 80° C. for 9 h
5. temperatureThe mixture was cooled to room temperature
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. dissolutionThe residue was dissolved in 9:1 hexanes/ether
9. additiontreated with 10% aqueous citric acid (3 mL)
10. filtrationThe organic layer was filtered through silica gel, which
11. washwas eluted with hexanes, methylene chloride, and ether