反应详情

温度

80 °C

118.5 g (0.58 mol) of 2,2,2-trifluoro-1-(4-methoxyphenyl)-ethanone are dissolved in 470 ml of ethanol and heated at 80° C. To the solution are added 42.4 g (0.61 mol) of hydroxylammonium chloride and 80.9 g (0.99 mol) of sodium acetate dissolved in 240 ml of water. The reaction mixture is refluxed for 5 hours, and the solvent is distilled off by a rotary evaporator. The residue is poured into 500 ml of water, and a white solid is precipitated. The solid is isolated by filtration and rinsed with water, and purified by recrystallization from toluene, yielding 73.1 g of 2,2,2-trifluoro-1-(4-methoxyphenyl)-ethanone oxime as a white solid. The structure is confirmed by the 1H-NMR spectrum (CDCl3). δ[ppm]: 3.84 (s, 3H), 6.99 (d, 2H), 7.55 (d, 2H), 9.11 (br s, 1H). The spectrum indicates the compound is a single isomer, which is tentatively assigned as Z-conformation.

1. temperatureThe reaction mixture is refluxed for 5 hours
2. distillationthe solvent is distilled off by a rotary evaporator
3. additionThe residue is poured into 500 ml of water
4. customa white solid is precipitated
5. customThe solid is isolated by filtration
6. washrinsed with water
7. custompurified by recrystallization from toluene