反应详情

温度

-70 °C

A mixture of 80 mL of THF and t-BuOK (7.0 g, 62.5 mmol) is added to a 250 mL four-neck flask equipped with a mechanical stirrer, a thermometer, a gas inlet tube and a 100 mL dropping funnel with a gas outlet tube. Cool down to −70° C. and 2,6-bis(trifluoromethyl)benzene (8.0 mL, 10.7 g, 50.0 mmol) is added dropwise and keep agitating ˜−70° C. for 30 min. Add n-BuLi (0.10 mol, 2.87 M in hexanes 35.0 mL, 100.0 mmol) dropwise over 30 min with agitation at ˜−70° C. for 60 min. Paraformaldehyde (6.0 g, 0.20 mol) is added and keep agitating ˜70° C. for 30 min, then gradually warm to room temperature for 3 h. Pour mixture into conc HCl (10 mL) and ice water (300 mL), and stir for 1 h. Extract with hexanes (3×50 mL). Wash the combined organic layers with 50 mL of brine, dry over anhydrous Na2SO4, filter and concentrate. The crude product is vacuum distilled (72-76° C. at 4-5 mm Hg) to give the desired compound (5 g).

1. additionis added to a 250 mL four-neck flask
2. customequipped with a mechanical stirrer
3. stirringkeep agitating ˜70° C. for 30 min
4. temperaturegradually warm to room temperature for 3 h
5. stirringstir for 1 h
6. extractionExtract with hexanes (3×50 mL)
7. washWash the combined organic layers with 50 mL of brine
8. dry with materialdry over anhydrous Na2SO4
9. filtrationfilter
10. concentrationconcentrate
11. distillationdistilled (72-76° C. at 4-5 mm Hg)