反应详情

Magnesium turnings (1.16 g, 0.048 mol) are stirred under a nitrogen atmosphere for 30 minutes, followed by dropwise addition of 4-bromo-2-ethyl-1-iodobenzene (15.0 g, 0.048 mol) as a solution in anhydrous tetrahydrofuran (40 ml), until the magnesium is just covered. A crystal of iodine is added and the reaction heated to reflux. After initiation begins external heating is stopped and the remaining aryl halide solution is added at such a rate as to maintain a controlled reflux. Once addition is complete the reaction is heated at reflux for 1 hour and the mixture is then cooled to room temperature. A solution of furan-2-carbaldehyde (4.0 ml, 0.048 mol) in anhydrous tetrahydrofuran (10 ml) is then added dropwise, and the suspension is then stirred at room temperature for 20 hours. The reaction is quenched with saturated ammonium chloride (200 ml) and extracted with ethyl acetate (200 ml). The organic phase is separated, dried over anhydrous magnesium sulfate then evaporated under reduced pressure. The crude product is purified by flash column chromatography (1:4 ethyl acetate/hexane eluant) to afford (4-bromo-2-ethyl-phenyl)furan-2-yl methanol as a brown oil.

1. temperaturethe reaction heated to reflux
2. temperatureAfter initiation begins external heating
3. temperatureto maintain a controlled reflux
4. additionOnce addition
5. temperatureis heated
6. temperatureat reflux for 1 hour
7. customThe reaction is quenched with saturated ammonium chloride (200 ml)
8. extractionextracted with ethyl acetate (200 ml)
9. customThe organic phase is separated
10. dry with materialdried over anhydrous magnesium sulfate
11. customthen evaporated under reduced pressure
12. customThe crude product is purified by flash column chromatography (1:4 ethyl acetate/hexane eluant)