反应详情

35 g (124 mmol) of 2,2,2-trifluoro-1-(4-phenoxyphenyl)-ethanone oxime (mixture of E- and Z-isomers) prepared according to the method described in example 80.1 is dissolved in 300 ml of methylene chloride. To the solution is added 1.1 ml of conc. HCl and stirred at room temperature for 4.5 hours. The reaction mixture is washed with water and brine, dried over MgSO4, and concentrated, yielding 33.4 g of 2,2,2-trifluoro-1-(4-methoxyphenyl)-ethanone oxime (single isomer) as a white solid. The structure is confirmed by the 1H-NMR spectrum (CDCl3). δ [ppm]: 7.00-7.12 (m, 4H), 7.19 (t, 1H), 7.39 (t, 2H), 7.57 (d, 2H), 8.95 (s, 1H).

1. washThe reaction mixture is washed with water and brine
2. dry with materialdried over MgSO4
3. concentrationconcentrated