反应详情

温度

120 °C

A stirred solution of potassium t-butoxide (5.0 g, 0.045 mol) in dry dimethylformamide (20 ml) at room temperature under a nitrogen atmosphere was treated with [[4-(ethoxycarbonyl)phenyl]methyl]triphenylphosphonium bromide (20.0 g, 0.0396 mol) in portions over 5 minutes. The resulting red suspension was stirred for 5 minutes and then treated dropwise with a solution of 1-(1H-imidazol-1-yl)-5-(4-methoxyphenyl)-2-pentanone (Example 8d; 4.0 g, 0.0155 mol) in dry dimethylformamidie (4 ml) over 5 minutes. The mixture was then heated at 120° C. for 1 hour. On cooling the reaction mixture was poured onto ice water (200 ml) and extracted with ethyl acetate (2×50 ml). The extracts were combined, washed with water, dried over magnesium sulfate and the solvent was evaporated off under reduced pressure to give the crude product. The crude product was purified by column chromatography (silica gel, 5% methanol in dichloromethane) to initially yield the less polar isomer, ethyl 4-[2-(1H-imidazol-1-ylmethyl)-5-(4-methoxyphenyl)-1Z-pentenyl]benzoate as a pale yellow oil having the following structural chracteristics:

1. temperatureOn cooling the reaction mixture
2. additionwas poured onto ice water (200 ml)
3. extractionextracted with ethyl acetate (2×50 ml)
4. washwashed with water
5. dry with materialdried over magnesium sulfate
6. customthe solvent was evaporated off under reduced pressure
7. customto give the crude product
8. customThe crude product was purified by column chromatography (silica gel, 5% methanol in dichloromethane)