反应详情

To the solution of 6-chloro-2,4-dimethoxy-benzaldehyde (8 g, 39.9 mmol) in dichloromethane (100 mL) was added boron tribromide (16 mL, 170 mmol) dropwise at −78° C. The reaction mixture was stirred overnight at room temperature and quenched by ice. The resulting mixture was extracted by EtOAc (2×50 mL). The combined organic layers were dried over anhydrous Na2SO4 and concentrated in vacuo. The residue was purified by column chromatography on silica gal (EtOAc/PE=1:5) to give the title compound as a yellow powder (4 g. Yield: 58%). 1H NMR (400 MHz, DMSO-d6) δ12.11 (s, 1H), 11.33 (s, 1H), 10.08 (s, 1H), 6.52-6.53 (d, J=2.0 Hz, 1H), 6.27-6.28 (s, J=2.0 Hz, 1H) MS (ESI) m/z=173 [M+H]+.

1. customquenched by ice
2. extractionThe resulting mixture was extracted by EtOAc (2×50 mL)
3. dry with materialThe combined organic layers were dried over anhydrous Na2SO4
4. concentrationconcentrated in vacuo
5. customThe residue was purified by column chromatography on silica gal (EtOAc/PE=1:5)