反应详情

To a solution of BH3.THF (0.9 mmol) in 20 mL anhydrous THF, was added dropwise at room temperature 158 mL (S)-2-methyl-CBS-oxazaborolidine in toluene and the mixture stirred for 5 min. To this mixture was slowly added methyl 4-(4-fluoro-3-methyl-phenyl)-4-oxo-butyric acid methyl ester (354 mg) in 5 mL THF and stirring continued for 30 min at 25° C. Saturated ammonium chloride (30 mL) was slowly added and the resulting mixture extracted with ethyl acetate (3×40 mL). The combined organic layers were washed with brine (2×20 mL) and dried over Na2SO4. The solvent was evaporated under reduced pressure and the product isolated by silica gel chromatography to afford 289 mg of the title compound as a colorless oil.

1. stirringstirring
2. waitcontinued for 30 min at 25° C
3. extractionthe resulting mixture extracted with ethyl acetate (3×40 mL)
4. washThe combined organic layers were washed with brine (2×20 mL)
5. dry with materialdried over Na2SO4
6. customThe solvent was evaporated under reduced pressure
7. customthe product isolated by silica gel chromatography