反应详情

To a solution of methyl 4-(4-bromophenyl)-4-oxobutanoate (8.0 g, 29 mmol) and NH2OH.HCl (4.8 g, 69 mmol) in MeOH (60 mL) was added a solution of CH3COONa (6.0 g, 73 mmol) in H2O (30 mL) at room temperature. The reaction mixture was heated at reflux for 1 h. The mixture was neutralized with saturated NaHCO3 solution and was extracted with ethyl acetate (50 mL×3). The combined organics were washed with brine, dried over anhydrous Na2SO4, and purified by chromatography on silica gel (3% ethyl acetate in petroleum ether) to afford methyl 4-(4-bromophenyl)-4-(hydroxyimino)butanoate (5.2 g, 62%). 1H NMR (CDCl3, 400 MHz) δ 7.52-7.49 (m, 4H), 3.66 (s, 3H), 3.08 (t, J=8.0, 2H), 2.61 (t, J=8.0, 2H).

1. temperatureThe reaction mixture was heated
2. temperatureat reflux for 1 h
3. extractionwas extracted with ethyl acetate (50 mL×3)
4. washThe combined organics were washed with brine
5. dry with materialdried over anhydrous Na2SO4
6. custompurified by chromatography on silica gel (3% ethyl acetate in petroleum ether)