反应详情

2-Amino-4,5-difluorobenzoic acid (5.37 g, 31.0 mmol) in THF (50 mL) was dropwise added to the suspension on LAH (1.65 g, 43.5 mmol) in THF (15 mL) at room temperature under N2 over 10 min. The resulting suspension was stirred at room temperature for 1 hr. Then the mixture was cooled down to 0° C., quenched with saturated Na2SO4 (100 mL), and extracted with Et2O (2×100 mL), the combined organic layers were washed with brine (60 mL), dried over MgSO4, and concentrated on rotary vacuum to afford the expected crude product as a brown solid, which was pure enough to be used in next step without further purification. 1H NMR (400 MHz, CDCl3) δ ppm 4.07 (s, 1 H), 4.56 (s, 2 H), 6.46 (dd, J=11.71, 6.92 Hz, 1 H), 6.87 (dd, J=10.58, 8.56 Hz, 1 H); Mass spec. 160.04 (MH+), Calc. for C7H7F2NO 159.05.

1. temperatureThen the mixture was cooled down to 0° C.
2. customquenched with saturated Na2SO4 (100 mL)
3. extractionextracted with Et2O (2×100 mL)
4. washthe combined organic layers were washed with brine (60 mL)
5. dry with materialdried over MgSO4
6. concentrationconcentrated on rotary vacuum