反应详情

To a solution of 50.0 g (0.413 mol) of 2,4-dimethylaniline in 1500 cm3 of glacial acetic acid, 21.2 ml (65.6 g, 0.410 mol) of bromine was added dropwise with vigorous stirring over ca. 20 minutes. This mixture was stirred for 2 hours at 40° C. The precipitate that formed was filtered off, washed with 50 ml of acetic acid, and dried in air. The resulting white solid was added to a solution of 100 g of potassium hydroxide in 400 ml of water. This mixture was stirred for 30 minutes. The crude product was extracted with 3×100 ml of dichloromethane. The combined extracts were dried over Na2SO4 and evaporated to dryness. Fractional distillation gave yellowish liquid, bp 83-85° C./1 mm Hg. Yield 46.9 g (57%).

1. stirringThis mixture was stirred for 2 hours at 40° C
2. customThe precipitate that formed
3. filtrationwas filtered off
4. washwashed with 50 ml of acetic acid
5. customdried in air
6. additionThe resulting white solid was added to a solution of 100 g of potassium hydroxide in 400 ml of water
7. stirringThis mixture was stirred for 30 minutes
8. extractionThe crude product was extracted with 3×100 ml of dichloromethane
9. dry with materialThe combined extracts were dried over Na2SO4
10. customevaporated to dryness
11. distillationFractional distillation
12. customgave yellowish liquid, bp 83-85° C./1 mm Hg