反应详情

A flask was charged with 7.0 g of α-methyl-4-fluorobenzyl cyanide, 15 g of KOH, 10 g of H2O and 2.0 g of triethylbenzyl ammonium chloride, and 10 ml of ethyl bromide was added dropwise to the mixture under stirring at 80° C. over a period of 1 hour. The mixture was maintained at the same temperature for 2 hours. The subsequent operation was carried out in the same manner as described above to give 7.9 g of crude α-ethyl-α-methyl-4-fluorobenzyl cyanide. 7.6 g of crude α-ethyl-α-methyl-4-fluorobenzyl cyanide, 20 ml of H2O and 20 ml of concentrated sulfuric acid were refluxed at 134° to 137° C. for 5.5 hours. The mixture was cooled to room temperature and extracted with benzene, and the benzene solution was extracted with dilute alkali and the obtained dilute alkali extract was adjusted to pH 7.5 with concentrated hydrochloric acid, and extracted with benzene to remove impurities. Then, the aqueous solution was adjusted to pH 4.6 with concentrated hydrochloric acid and extracted with benzene. The benzene extract was washed with water, dried over Na2SO4, and evaporated under reduced pressure to give 3.8 g of 2-(4-fluorophenyl)-2-methylbutyric acid.

1. extractionextracted with benzene
2. extractionthe benzene solution was extracted with dilute alkali
3. additionthe obtained dilute alkali
4. extractionextract
5. extractionextracted with benzene
6. customto remove impurities
7. extractionextracted with benzene
8. extractionThe benzene extract
9. washwas washed with water
10. dry with materialdried over Na2SO4
11. customevaporated under reduced pressure