反应详情

温度

30 °C

To an ice-cooled solution of (1R)-1,8,8-trimethylbicyclo[3.2.1]octane-2,4-dione (0.90 g, 5.0 mmole), triethylamine (0.50 g, 5.0 mmole) and 4-(dimethylamino)pyridine (0.61 g, 5.0 mmole) in dry dichloromethane (100 mL) was added a solution of 3,4-dichlorophenyl isocyanate (0.94 g, 10.0 mmole) in dry dichloromethane (25 mL). The resulting mixture was allowed to stir overnight under a nitrogen atmosphere, during which time it came up to room temperature, and then was heated at 30° C. for 24 hours. The reaction mixture was treated with 2N aqueous HCl and the layers separated. The acidic aqueous layer was extracted with two additional portions of dichloromethane. The combined organic layers were dried over anhydrous sodium sulfate and concentrated on a rotary evaporator to give a yellow oil, which was purified by chromatography on silica gel (10% ethyl acetate/hexane) to yield a yellow oil, which was crystallized from 95% ethanol to yield the title compound as a beige solid (1.07 g, 58% yield), mp=89–91° C.; MS (−) ESI m/z=366 (M−H)−; [α]D25=+25.9° (c=1, EtOH).

1. customcame up to room temperature
2. customthe layers separated
3. extractionThe acidic aqueous layer was extracted with two additional portions of dichloromethane
4. dry with materialThe combined organic layers were dried over anhydrous sodium sulfate
5. concentrationconcentrated on a rotary evaporator
6. customto give a yellow oil, which
7. customwas purified by chromatography on silica gel (10% ethyl acetate/hexane)
8. customto yield a yellow oil, which
9. customwas crystallized from 95% ethanol