反应详情

Trimethylacetyl chloride (4.2 mL, 34.1 mL) was fast dropwise added to a solution of 2-bromo-5-fluorobenzenamine (4.31 g, 22.7 mmol) in CH2Cl2 (50 mL) at room temperature, followed by the addition of DIEA (7.9 mL, 45.4 mmol). The resulting mixture was stirred at room temperature for 2 hrs, and then partitioned between HCl (1N, 200 mL) and EtOAc (250 mL). After separation, the organic phase was washed with brine (50 mL), dried on MgSO4, concentrated on rotary vacuum, and purified on flash chromatography eluting with 20˜40% EtOAc/hexanes (1200 mL) to afford the expected product, as a colorless oil (6.07 g, 98% yield); 1H NMR (400 MHz, CDCl3) δ ppm 1.33 (s, 9H), 6.69 (ddd, J=8.81, 7.55, 3.02 Hz, 1H), 7.45 (dd, J=8.81, 5.79 Hz, 1H), 8.04 (s, 1H), 8.28 (dd, J=11.08, 3.02 Hz, 1H); Mass spec. 274.04 (MH+), Calc. for C11H13BrFNO 273.02.

1. custompartitioned between HCl (1N, 200 mL) and EtOAc (250 mL)
2. customAfter separation
3. washthe organic phase was washed with brine (50 mL)
4. customdried on MgSO4
5. concentrationconcentrated on rotary vacuum
6. custompurified on flash chromatography
7. washeluting with 20˜40% EtOAc/hexanes (1200 mL)