反应详情

温度

-70 °C

4-Bromo-2-iodoethyl benzene (50.0 g, 0.161 mol) is dissolved in anhydrous tetrahydrofuran (250 ml) and cooled to −70° C. under an atmosphere of nitrogen. Isopropylmagnesium chloride (2 M solution in tetrarhydrofuran, 100 ml, 0.200 mmol) is added dropwise with vigorous stirring over 40 minutes, maintaining the internal temp below −60° C. by external cooling. When the addition is complete, the reaction is stirred at −70° C. for 20 minutes then allowed to warm to room temperature over 1 hour and 20 minutes. The reaction mixture is then cooled to −70° C. and a solution of 2-furaldehyde (16 ml, 18.6 g, 190 mmol) in tetrahydrofuran (50 ml) is added dropwise over 40 minutes. On completion of the addition, the reaction is allowed to warm to room temperature and stirred at room temperature for 3 hours. Saturated aqueous ammonium chloride solution (˜500 ml) is added and the mixture is extracted into ethyl acetate. The organic solutions are combined, washed with brine, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue is further purified by column chromatography on silica gel to give (5-bromo-2-ethylphenyl)furan-2-ylmethanol.

1. temperaturemaintaining the internal temp below −60° C. by external cooling
2. additionWhen the addition
3. stirringthe reaction is stirred at −70° C. for 20 minutes
4. temperatureto warm to room temperature over 1 hour and 20 minutes
5. temperatureThe reaction mixture is then cooled to −70° C.
6. additionOn completion of the addition
7. temperatureto warm to room temperature
8. stirringstirred at room temperature for 3 hours
9. extractionthe mixture is extracted into ethyl acetate
10. washwashed with brine
11. dry with materialdried over anhydrous magnesium sulfate
12. concentrationconcentrated under reduced pressure
13. customThe residue is further purified by column chromatography on silica gel