반응 #436963
ord-e0fd581e89874e7a8632da32c57c36a2
반응 방정식
반응 조건
후처리
- 1기타came up to room temperature
- 2기타the layers separated
- 3추출The acidic aqueous layer was extracted with two additional portions of dichloromethane
- 4건조The combined organic layers were dried over anhydrous sodium sulfate
- 5농축concentrated on a rotary evaporator
- 6기타to give a yellow oil, which
- 7기타was purified by chromatography on silica gel (10% ethyl acetate/hexane)
- 8기타to yield an orange oil, which
- 9기타was crystallized from 95% ethanol
실험 절차
To an ice-cooled solution of (1R)-1,8,8-trimethylbicyclo[3.2.1]octane-2,4-dione (0.36 g, 2.0 mmole), triethylamine (0.20 g, 2.0 mmole) and 4-(dimethylamino)pyridine (0.24 g, 2.0 mmole) in dry dichloromethane (25 mL) was added a solution of 4-nitrophenyl isocyanate (0.33 g, 2.0 mmole) in dry dichloromethane (5 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 an orange oil, which was crystallized from 95% ethanol to yield the title compound as an off-white solid (0.20 g, 30% yield), mp=168–170° C.; MS (−) ESI m/z=343 (M−H)−; [α]D25=+29.4° (c=1, DMSO).