反应详情

温度

70 °C

Under anhydrous conditions and in a nitrogen atmosphere, 70 g. (0.30 mole) 6,8-dihydroxy-3a,4-dihydro-(2H,3H)-pyrrolo[1,2-a]quinolin-1,5-dione was dissolved in 750 ml. dimethylformamide by warming to 60° C. To the resulting deep red solution was added 51.6 g. (0.675 mole) potassium carbonate. The mixture was heated to 70° C., a solution of 2-methylsulfonyloxy-5-phenylpentane in 250 ml. dimethylformamide was added in a fast stream, and heated at 75°-80° C. for 12 hours. Additional portions of 2-methylsulfonyloxy-5-phenylpentane (5.3 g.) and potassium carbonate (3.8 g.) and heating continued at 75°-80° C. for two hours. The mixture was poured over a mixture (one liter each) ethyl acetate and ice and, after shaking in a separtory funnel, the layers were separated. The aqueous phase was extracted with 5×1000 ml. ethyl acetate. The combined organic layers were washed with 3×4 liters water, 3×2 liters of 0.5N hydrochloric acid, dried (MgSO4) and concentrated to a volume of about 2.5 liters. Upon cooling, the precipitated product which formed was collected: 9.0 g., M.P. 151°-153° C. The mother liquor was concentrated to half volume, cooled, and a second crop, 34.2 g., M.P. 148°-151° C., was collected. Total yield by crystallization: 52.2 g. This material was shown to be primarily a single diastereomer, designated as "Diastereomer B." Upon recrystallization from ethyl acetate, colorless crystals were obtained, M.P. 159°-161° C. This was found to be about 90% diastereomer B. 1H--NMR (CDCl3) ppm (delta): 1.33 (d, 3H, J=6 Hz).

1. additionTo the resulting deep red solution was added 51.6 g
2. temperatureheated at 75°-80° C. for 12 hours
3. customthe layers were separated
4. extractionThe aqueous phase was extracted with 5×1000 ml
5. washThe combined organic layers were washed with 3×4 liters water, 3×2 liters of 0.5N hydrochloric acid
6. dry with materialdried (MgSO4)
7. concentrationconcentrated to a volume of about 2.5 liters
8. temperatureUpon cooling
9. customthe precipitated product which formed
10. customwas collected
11. concentrationThe mother liquor was concentrated to half volume
12. temperaturecooled
13. custom, M.P. 148°-151° C., was collected
14. customTotal yield by crystallization
15. custom" Upon recrystallization from ethyl acetate
16. customcolorless crystals were obtained