反应详情

The product from Method I (57 mg, 0.3 mmol) was suspended in 3:0 mL of tert-butanol and to this solution was added piperidine (90 μL, 0.9 mmol) and the resulting system heated at reflux for 1 hour. The reaction mixture was cooled to room temperature and water was added (4.0 mL). The solution was adjusted to pH 1 with 1 N HCl and then washed with ether. The aqueous layer was removed and adjusted to pH 12 with 2 N NaOH. The solution was then extracted 2×15 mL with dichloromethane and the combined organics washed with water then brine and dried over MgSO4. Evaporation of solvent afforded 45 mg of a yellow solid that was purified by silica-gel chromatography (3:1 ethyl acetate/hexanes) to yield 23 mg (32%) of the title compound as a light yellow solid. Mp 170-172° C. 1H NMR (400 MHz, CDCl3)δ: 1.67-1.74 (m, 6H), 3.65-3.67 (m, 4H), 7.10 (s, 1H), 8.31 (s, 1H), LRMS: 237 (M+1).

1. temperaturethe resulting system heated
2. temperatureat reflux for 1 hour
3. washwashed with ether
4. customThe aqueous layer was removed
5. extractionThe solution was then extracted 2×15 mL with dichloromethane
6. washthe combined organics washed with water
7. dry with materialbrine and dried over MgSO4
8. customEvaporation of solvent