反应详情

温度

60 °C

To a solution of tert-butyl 4-(3-methylbutanoyl)benzoate (500 mg, 1.91 mmol) and ammonium acetate (1.50 g, 19.1 mmol) in methanol (9.5 mL) was added sodium cyanoborohydride (189 mg, 2.86 mmol). The mixture was heated to 60° C. for 21 hours, then cooled to room temperature. 1 N hydrochloric acid (7 mL) was added dropwise. After 1 hour, the mixture was concentrated under reduced pressure to remove methanol. 1 N sodium hydroxide (10 mL) was added, and the mixture was extracted with dichloromethane (3×25 mL). The combined organics were washed with sat. aq sodium chloride (15 mL), dried over anhydrous Na2SO4, and filtered, and the filtrate was concentrated. Purification by silica gel flash chromatography (methanol/dichloromethane) gave tert-butyl(+/−)-4-(1-amino-3-methylbutyl)benzoate as a colorless oil. 1H NMR (400 MHz, CDCl3) δ 7.99-7.94 (m, 2H), 7.41-7.37 (m, 2H), 4.08-4.01 (m, 1H), 1.60 (s, 9H), 1.59-1.43 (m, 3H), 0.92 (d, J=6.5 Hz, 3H), 0.90 (d, J=6.3 Hz, 3H).

1. temperaturecooled to room temperature
2. concentrationthe mixture was concentrated under reduced pressure
3. customto remove methanol
4. addition1 N sodium hydroxide (10 mL) was added
5. extractionthe mixture was extracted with dichloromethane (3×25 mL)
6. washThe combined organics were washed with sat. aq sodium chloride (15 mL)
7. dry with materialdried over anhydrous Na2SO4
8. filtrationfiltered
9. concentrationthe filtrate was concentrated
10. customPurification by silica gel flash chromatography (methanol/dichloromethane)