反应详情

A mixture of 5-bromoveratraldehyde (100 mg, 0.41 mmol) and (triphenylphosphoranylidene)acetaldehyde (137 mg, 0.45 mmol) in dry benzene (2.5 ml) was refluxed for 9 h and the solvent was removed. The crude product was passed through a short silica gel column (bond-elute) (eluents: 10% ethyl acetate in hexane), giving 3-(3-bromo-4,5-dimethoxy-phenyl)-propenal (50 mg, 45%). 1H NMR (CDCl3): 9.68 (d, J=7.6 Hz, 1H), 7.36 (d, J =1.8 Hz, 1H), 7.34 (d, J=15.8 Hz, 1H), 7.03 (d, J=1.9 Hz, 1H), 6.62 (dd, J=7.6, 16.0 Hz, 1H), 3.913 (s, 3H), 3.907 (s, 3H) (the sample contained trace amount of starting material).

1. temperaturewas refluxed for 9 h
2. customthe solvent was removed
3. washThe crude product was passed through a short silica gel column (bond-elute) (eluents: 10% ethyl acetate in hexane)