反应详情

To a solution of 2,6-dichloro-4-aminobenzoic acid methyl ester (2.80 g) in CH2Cl2 (20 mL) at −10° C. was added a solution of tetrabutylammonium tribromide (6.94 g) in CH2Cl2 (30 mL) dropwise at −10° C. After 2 h, the mixture was warmed to room temperature, washed with satd. NaHCO3 and brine, dried (Na2SO4), filtered, and concentrated. The residue was purified by column chromatography (silica gel; eluent: EtOAc/hexane 1:4) to yield 2,6-dichloro-3-bromo-4-aminobenzoic acid methyl ester (2.99 g) ESMS: m/z 298 (MH+).

1. washwashed with satd
2. dry with materialNaHCO3 and brine, dried (Na2SO4)
3. filtrationfiltered
4. concentrationconcentrated
5. customThe residue was purified by column chromatography (silica gel; eluent: EtOAc/hexane 1:4)