反应详情

To a stirred solution of (2E)-3-(2,4-Dichlorophenyl)acrylic acid (10 g, 46 mmol) in ethanol (60 ml) was added conc. H2SO4 (2.5 ml). The mixture was heated to reflux and for 48 H, then allowed to cool, concentrated in vacuo, dissolved in ethyl acetate, washed three times with 4N NaOH, dried over sodium sulfate and concentrated in vacuo to afford ethyl (2E)-3-(2,4-dichlorophenyl)acrylate (10.7 g) as pale brown crystals. 1H NMR δ (ppm)(CDCl3): 8.00 (1 H, d, J=16.1 Hz), 7.55 (1 H, d, J=8.5 Hz), 7.44 (1 H, d, J=1.9 Hz), 7.26 (1 H, dd, J=2.0, 8.4 Hz), 6.41 (1 H, d, J=16.1 Hz), 4.28 (2 H, q, J=7.1 Hz), 1.34 (3 H, t, J=7.1 Hz).

1. temperatureThe mixture was heated
2. temperatureto reflux and for 48 H
3. temperatureto cool
4. concentrationconcentrated in vacuo
5. dissolutiondissolved in ethyl acetate
6. washwashed three times with 4N NaOH
7. dry with materialdried over sodium sulfate
8. concentrationconcentrated in vacuo