1,4-Diisopropylbenzene → 2,5-Diisopropyl-1-bromo-benzene

HRID 1657922Notes

Reaction equation

HRID 1657922 reaction equation
[CH:1]([C:4]1[CH:9]=[CH:8][C:7]([CH:10]([CH3:12])[CH3:11])=[CH:6][CH:5]=1)([CH3:3])[CH3:2].[Br:13]Br>[Fe].C(Cl)(Cl)(Cl)Cl>[Br:13][C:9]1[CH:8]=[C:7]([CH:10]([CH3:12])[CH3:11])[CH:6]=[CH:5][C:4]=1[CH:1]([CH3:3])[CH3:2]

Participants

5

Reactant 2

HCID 74861,4-DiisopropylbenzeneHCID 24408Bromine

Product 1

HCID 119589802,5-Diisopropyl-1-bromo-benzene

Reagents, catalysts & solvents 2

HCID 23925IronCatalystHCID 5943Carbon TetrachlorideSolvent2×

Procedure

To a one-liter flask containing 243 parts of p-diisopropylbenzene, 300 parts of carbon tetrachloride and 2.5 parts of iron powder is added dropwise 240 parts of bromine and sufficient carbon tetrachloride to make 180 parts of solution during seven hours at a temperature of -5°C. The solution is decanted from the residual ferric bromide and washed twice with 3N HCl. The carbon tetrachloride is removed under reduced pressure. A solution of 40 parts potassium hydroxide in two hundred parts of ethyl alcohol is added and refluxed 0.5 hr. The solution is poured into water, separated, washed with dilute hydrochloric acid, dilute sodium bisulfite solution and water, and dried. The solvent is removed and the 2-bromo-1,4-diisopropylbenzene distilled, bp 142°C at 25 mm, nD25 1.5292.

Workup

  1. customduring seven hours
  2. customat a temperature of -5°C
  3. customThe solution is decanted from the residual ferric bromide
  4. washwashed twice with 3N HCl
  5. customThe carbon tetrachloride is removed under reduced pressure
  6. additionA solution of 40 parts potassium hydroxide in two hundred parts of ethyl alcohol is added
  7. temperaturerefluxed 0.5 hr
  8. additionThe solution is poured into water
  9. customseparated
  10. washwashed with dilute hydrochloric acid, dilute sodium bisulfite solution and water
  11. customdried
  12. customThe solvent is removed
  13. distillationthe 2-bromo-1,4-diisopropylbenzene distilled

Sources & evidence

ORD record
ord-1ba6b8488bf345f79ddd9f1fd5d776a0
Source dataset
uspto-grants-1976_06
Patent number
US03962307

Reaction notes

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