反应详情

3-(N,N,N-trimethylammonio)-1-(3,4,5-trimethoxyphenyl)propan-1-one iodide (355.9 g, 0.87 mole) was suspended in a mixture of water (3.56 L) and of ethyl acetate (2.54 L) and refluxed with rapid stirring for 2-3 hours. The mixture was cooled and the pale yellow organic layer was removed. Fresh ethyl acetate (2 L) was added and the mixture was refluxed for 1 hour, and the process was repeated once again. The organic layers were combined, washed with brine, dried over anhydrous MgSO4, and evaporated to dryness to provide a yellow oil, which was crystallized from hexane/ether to give 3,4,5-trimethoxyphenylvinyl ketone (m.p. 45°-47° C.). 200 MHz 1H NMR (CDCl3): δ 3.94 (9H, s, 3 OCH3), 5.92 (1H, dd, J=1.5 Hz, J=9 Hz), 6.44 (1H, dd, J=1.5 Hz, J=1.5 Hz, J=16 Hz), 7.18 (1H, dd, J=16 Hz, J=9 Hz), 7.28 (2H, H2 and H6).

1. temperaturerefluxed
2. temperatureThe mixture was cooled
3. customthe pale yellow organic layer was removed
4. additionFresh ethyl acetate (2 L) was added
5. temperaturethe mixture was refluxed for 1 hour
6. washwashed with brine
7. dry with materialdried over anhydrous MgSO4
8. customevaporated to dryness
9. customto provide a yellow oil, which
10. customwas crystallized from hexane/ether