反应详情

温度

0 °C

To a suspension of 1.85 g (77.1 mmol) NaH in 130 mL dry THF, 25.4 g (75.1 mmol) tert-butoxycarbonyl-1-ethoxycarbonylethylidendiethoxy-phosphorane (2) was added dropwise at 0° C., The reaction mixture was stirred for 6 h at 0° C. under Ar. This solution was added under Ar dropwise at 0° C. to 15.5 g (63.5 mmol) 2-bromo-5-isopropoxy-benzaldehyde (1), dissolved in 80 mL dry THF. The cooling bath was removed and the reaction mixture was stirred overnight at room temperature. 20 mL water was added and the solvent was removed under reduced pressure. The residue was partitioned between water and dichloromethane. The organic layers were dried (MgSo4), filtered and the solvent was removed under reduced pressure to afford 16.5 g (61%) (E)-3-carboethoxy-4-(2'-bromo-5-isopropylphenyl)-3-butenic acid-tert-butyl ester as a yellow oil.

1. additionwas added dropwise at 0° C.
2. customThe cooling bath was removed
3. stirringthe reaction mixture was stirred overnight at room temperature
4. addition20 mL water was added
5. customthe solvent was removed under reduced pressure
6. customThe residue was partitioned between water and dichloromethane
7. customThe organic layers were dried (MgSo4)
8. filtrationfiltered
9. customthe solvent was removed under reduced pressure