反应详情

温度

55 °C

The crude 1-bromo-3-(bromomethyl)-5-methylbenzene obtained from step 5 (188 g, ˜0.71 M) was dissolved in ethanol (470 mL) by warming in an oil bath (50-60° C.). Potassium cyanide (69.57 g, 1.068 M) was added, then distilled water (235 mL). The mixture was heated to reflux and stirred for 3 hr. After cooling to room temperature, the mixture was evaporated in vacuo and the residue was diluted with ether, washed with water, dried with MgSO4, filtered, and evaporated in vacuo. The residue was dissolved in dichloromethane and ethyl acetate-hexane (1:20) and loaded onto a silica gel column and eluted with ethyl acetate-hexane (from 1:20 to 1:6) to afford 85 g (53% for 2 steps) of 3-bromo-5-methylbenzyl cyanide (5) as a pale brown oil.

1. temperatureThe mixture was heated
2. temperatureto reflux
3. temperatureAfter cooling to room temperature
4. customthe mixture was evaporated in vacuo
5. additionthe residue was diluted with ether
6. washwashed with water
7. dry with materialdried with MgSO4
8. filtrationfiltered
9. customevaporated in vacuo
10. dissolutionThe residue was dissolved in dichloromethane
11. washeluted with ethyl acetate-hexane (from 1:20 to 1:6)