反应详情

A solution of n-butyl lithium (29 ml. of 2.2 M) is added dropwise to 3,5-dimethoxybenzyl triphenylphosphonium bromide (31.5 g.) in tetrahydrofuran (200 ml.) with stirring and the resulting deep red solution is stirred for one-half hour. Benzyl acetone (9.4 g.) is added dropwise and the reaction mixture stirred for 12 hours. It is then adjusted to pH 7 by addition of acetic acid and concentrated under reduced pressure. The residue is extracted with methylene chloride and the extract evaporated to give crude 1-(3,5-dimethoxyphenyl)-2-methyl-4-phenyl-1-butene as an oil. It is purified by chromatography on silica gel (400 g.) and elution with benzene. Yield: 10 g. as an oil.

1. stirringthe resulting deep red solution is stirred for one-half hour
2. stirringthe reaction mixture stirred for 12 hours
3. concentrationconcentrated under reduced pressure
4. extractionThe residue is extracted with methylene chloride
5. customthe extract evaporated