Azobisisobutyronitrile → Ethyl 2-[4-(bromomethyl)phenoxy]propanoate

Temperature

40 °C

17 gm (0.08 mol) of ethyl 2-(4-methyl-phenoxy) -propionate and 0.2 gm of 2,2'-azo-bis-(2-methyl-propionitrile) were dissolved in 100 ml of chloroform, and the solution was heated to its boiling point. One-half of a solution of 5.4 ml of bromine in 20 ml of chloroform was then added to the boiling solution over a period of 45 minutes. The reaction mixture was now cooled to about 40° C., an additional 0.2 gm of the catalyst was added, the mixture was again heated to its boiling point, and the other half of the chloroformic bromine solution was added. The mixture was kept boiling for two hours more and was then cooled to room temperature. The resulting reddish-brown solution was extracted three times with 100 ml each of a saturated aqueous sodium bicarbonate solution, the combined aqueous extracts were extracted twice with 50 ml each of methylene chloride, and the combined organic extracts were dried over sodium sulfate. The methylene chloride was now distilled off in a water aspirator vacuum, and the liquid evaporation residue was fractionally distilled in an oil pump vacuum, yielding 70% of theory of ethyl 2-(4-bromomethyl-phenoxy)-propionate, b.p. 128°-134° C. at 0.2 mm Hg.

1. temperaturethe solution was heated to its boiling point
2. temperaturethe mixture was again heated to its boiling point
3. temperaturemore and was then cooled to room temperature
4. extractionThe resulting reddish-brown solution was extracted three times with 100 ml each of a saturated aqueous sodium bicarbonate solution
5. extractionthe combined aqueous extracts were extracted twice with 50 ml each of methylene chloride
6. dry with materialthe combined organic extracts were dried over sodium sulfate
7. distillationThe methylene chloride was now distilled off in a water
8. customthe liquid evaporation residue
9. distillationwas fractionally distilled in an oil pump vacuum

ORD record

ord-d724c489e1fb4c068782212a46b21f6a

Source dataset

uspto-grants-1979_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04169720