反应详情

35.6 g of (methoxycarbonylmethylene)-triphenylphosphorane is added to a solution of 8.48 g of 2,6-dimethoxybenzaldehyde in 450 ml of tetrahydrofuran under nitrogen and refluxed for 16 hours. It is poured on 200 ml of ice water, extracted three times with ethyl acetate, the combined organic phases are washed once with saturated sodium chloride solution, dried on sodium sulfate and after filtration, concentrated by evaporation in a vacuum. The thus obtained residue is purified by chromatography on silica gel. With hexane/0-40% ethyl acetate, a solid is obtained, which is recrystallized from hexane/toluene. 10.6 g of the title compound is obtained in this-way as crystalline substance (melting point: 76°-78° C).

1. temperaturerefluxed for 16 hours
2. extractionextracted three times with ethyl acetate
3. washthe combined organic phases are washed once with saturated sodium chloride solution
4. customdried on sodium sulfate
5. filtrationafter filtration
6. concentrationconcentrated by evaporation in a vacuum
7. customThe thus obtained residue is purified by chromatography on silica gel
8. customWith hexane/0-40% ethyl acetate, a solid is obtained
9. customwhich is recrystallized from hexane/toluene