2,4-Dimethylaniline → 2-Bromo-4,6-dimethylaniline

Temperature

40 °C

21.2 ml (65.6 g, 0.410 mol) of bromine were added dropwise, while vigorously stirring, over ca. 20 minutes to a solution of 50.0 g (0.413 mol) of 2,4-dimethylaniline in 1500 cm3 of glacial acetic acid. 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. Then, this 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 extract was dried over Na2SO4 and evaporated to dryness. Fractional distillation gave a yellowish liquid, bp 83-85° C./1 mm Hg. Yield 46.9 g (57%).

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

ORD record

ord-949fd7fa157948a88894168f7636bdb3

Source dataset

uspto-grants-2010_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07667064B2