反应详情

温度

-78 °C

The procedure was adopted from the previously published literature (J. Org. Chem. 1986, 51, 113-114). To a flame-dried flask, 2-hydroxy benzyl alcohol (10 g, 80 mg) and 400 mL CH2Cl2 was added. The reaction mixture was cooled to −78° C. by use of a dry ice/acetone bath. Following the addition of liquefied 2-methylpropene (40 mL), trifluoromethanesulfonic acid (2 mL, 22 mmol) was added. The reaction mixture was stirred for 5 hr while maintaining the temperature at −78° C. The reaction was quenched with triethylamine and then allowed to warm to room temperature. The solvent was removed by distillation under reduced pressure and the oily product was triturated with 500 mL petroleum ether several times. Petroleum ether was then evaporated and the crude product was purified by silica gel column with the following eluents: 20% EtOAc/80% Hexane. The product was isolated as pale yellow oil (30% yield). 1H NMR (CDCl3) δ 7.286 (dd, 1H, Ar), 7.195 (ddd, 1H, Ar), 7.063 (d, 1H, Ar), 7.003 (ddd, 1H, Ar), 4.669 (s, 2H, —CH2—), 1.447 (s, 9H, —C(CH3)3—). Mass Spec.=180.24 (M+H)+.

1. additionwas added
2. temperaturewhile maintaining the temperature at −78° C
3. customThe reaction was quenched with triethylamine
4. temperatureto warm to room temperature
5. customThe solvent was removed by distillation under reduced pressure
6. customthe oily product was triturated with 500 mL petroleum ether several times
7. customPetroleum ether was then evaporated
8. customthe crude product was purified by silica gel column with the following eluents