反应详情

Methyl 3-methylbenzoate (6.0 g, 40 mmol), tetrahydrofuran (50 mL), and 4-picoline (4.1 g, 44 mmol) were stirred at −78° C. under an atmosphere of nitrogen. Sodium bis(trimethylsilyl)amide 1.0 M in THF (88 mL, 88 mmol) was added dropwise. The mixture was allowed to warm to room temperature and stir for 16 h when it was poured into saturated aqueous sodium bicarbonate solution. The mixture was then extracted with ethyl acetate (3×50 mL). The combined organics were washed with brine (2×50 mL), dried over magnesium sulfate, and concentrated. The product was recrystallized from ethyl acetate/hexane to yield a light yellow solid (5.7 g, 67%): mp 118.0-119.0° C. 1H NMR (acetone-d6/300 MHz) 8.50 (m, 2H), 7.90 (m, 2H), 7.44 (m, 2H), 7.29 (m, 2H), 4.45 (s, 2H), 2.41 (s, 3H). ESHRMS m/z 212.1067 (M+H, C14H13NO requires 212.1075).

1. extractionThe mixture was then extracted with ethyl acetate (3×50 mL)
2. washThe combined organics were washed with brine (2×50 mL)
3. dry with materialdried over magnesium sulfate
4. concentrationconcentrated
5. customThe product was recrystallized from ethyl acetate/hexane