Reaktion #2713
ord-b76082d12d914f36b18aec03d29abfbc
Reaktionsgleichung
Edukte
Reagenzien
Reaktionsbedingungen
Aufarbeitung
- 1workup.STIRRINGthe mixture was stirred for 5 hours
- 2Waschenwashed with brine (10 mL)
- 3Sonstigedried
- 4Sonstigethe solvent was removed by evaporation
- 5Sonstigeto obtain the E and Z olefinic compounds, which
- 6Temperaturcooled to -50° C
- 7TemperaturThe reaction mixture was gradually warmed to -10° C. over 3hours
- 8Sonstigequenched with methanol and water
- 9workup.ADDITIONThe reaction mixture was diluted with ethyl acetate (100 mL)
- 10WaschenThe organic layer was washed with brine
- 11Sonstigedried
- 12SonstigeSolvent was removed under reduced pressure
- 13Sonstigethe residue purified by chromatography on silicagel
Vorschrift
To a cold (-78° C.) solution of ethyl 4-(diethoxyphosphoryl-3,3-dimethoxypropyl)benzoate (Compound D, 1.4 g, 3.6 mmol) in THF (9 mL) was added n-BuLi in hexane (1.6M solution, 2.8 mL). The mixture was gradually warmed to ambient temperature over 30 minutes and stirred for 5 minutes. To this mixture was added 2,2-dimethyl-4(tol-4-yl)-chrom-3-en-6-al (Compound Q, 260 mg, 0.93 mmol) in THF (1 mL) at ambient temperature and the mixture was stirred for 5 hours. The reaction mixture was diluted with ethyl acetate (100 mL) and washed with brine (10 mL) dried and the solvent was removed by evaporation. The residual material was subjected to flash chromatography on silicagel to obtain the E and Z olefinic compounds, which were dissolved in dichloromethane (5 mL) and cooled to -50° C. A solution of SnCl4 in dichloromethane (150 mg in 0.7 mL) was added to the olefinic compounds. The reaction mixture was gradually warmed to -10° C. over 3hours and then quenched with methanol and water. The reaction mixture was diluted with ethyl acetate (100 mL). The organic layer was washed with brine and dried. Solvent was removed under reduced pressure and the residue purified by chromatography on silicagel to afford the title compound as a white solid.