反应详情

A solution of 3-bromo-2-chloropyridine (50 g, 0.26 mol) and 3-chloroperoxybenzoic acid (70-75% wet with water; 67.3 g, 0.39 mol) in 1,2-dichloroethane (600 mL) was heated under reflux for 7 hours. The reaction was then concentrated under reduced pressure to an approximate volume of 200 mL and purified by chromatography on silica gel (Gradient: 80% to 100% ethyl acetate in heptane, followed by 5% to 10% methanol in ethyl acetate) to yield the title compound as a brown solid. Yield: 32.9 g, 0.158 mol, 61%. LCMS m/z 210.0 (M+1). 1H NMR (400 MHz, CDCl3) δ 7.09 (dd, J=7.8, 6.9 Hz, 1H), 7.52 (d, J=8.2 Hz, 1H), 8.33 (d, J=6.4 Hz, 1H).

1. temperatureunder reflux for 7 hours
2. concentrationThe reaction was then concentrated under reduced pressure to an approximate volume of 200 mL
3. custompurified by chromatography on silica gel (Gradient: 80% to 100% ethyl acetate in heptane, followed by 5% to 10% methanol in ethyl acetate)