反应详情

To a solution of the title compound of Step C (7.0 g, 24.8 mmol) in dichloromethane (60 mL) cooled to -78° C. under a nitrogen atmosphere was added a 1 Molar solution of DIBAL (diisobutylaluminum hydride) in dichloromethane (62 mL, 62 mmol). After the addition was complete, the reaction mixture was allowed to warm to room temperature for 1 h. An additional portion of 1 Molar solution of DIBAL in dichloromethane (31 mL) was added at -78° C. and the mixture warmed to room temperature for 1 h. The reaction was quenched with 1 N HCl and extracted three times with dichloromethane. The combined organic phases were washed with saturated ammonium chloride solution, dried (MgSO4) and concentrated under reduced pressure. The residue was triturated to afford 4.4 g of the title compound of Step D as a solid. 1H NMR (CDCl3): δ 7.44 (apparent d,2H), 7.33 (t,1H), 4.46 (m,2H), 3.57 (s,3H), 2.66 m,1H), 2.18 (s,3H).

1. additionAfter the addition
2. temperaturethe mixture warmed to room temperature for 1 h
3. customThe reaction was quenched with 1 N HCl
4. extractionextracted three times with dichloromethane
5. washThe combined organic phases were washed with saturated ammonium chloride solution
6. dry with materialdried (MgSO4)
7. concentrationconcentrated under reduced pressure
8. customThe residue was triturated