Bromine → 1-Bromo-2,4-di-tert-butylbenzene

HRID 37628Notes

Reaction equation

HRID 37628 reaction equation
[C:1]([C:5]1[CH:10]=[CH:9][CH:8]=[C:7]([C:11]([CH3:14])([CH3:13])[CH3:12])[CH:6]=1)([CH3:4])([CH3:3])[CH3:2].[Br:15]Br>C(O)(=O)C.[N+]([O-])([O-])=O.[Ag+]>[CH3:12][C:11]([C:7]1[CH:6]=[C:5]([C:1]([CH3:4])([CH3:3])[CH3:2])[CH:10]=[CH:9][C:8]=1[Br:15])([CH3:14])[CH3:13]

Participants

5

Reactant 2

HCID 24408BromineHCID 1368101,3-Di-tert-butylbenzene

Product 1

HCID 110764641-Bromo-2,4-di-tert-butylbenzeneYield 99.9%

Reagents, catalysts & solvents 2

HCID 24470Silver NitrateCatalystHCID 176Acetic AcidSolvent

Procedure

To a solution of 5.00 g (26.3 mmoles) of 1,3-di-t-butylbenzene in 15 ml of acetic acid was added 4.47 g (26.3 mmoles) of silver nitrate. The mixture was stirred in an oil bath at 75°-80° and then bromine (4.21 g, 26.3 mmoles) was added in small portions over 2 hours. After the addition was complete, the reaction mixture was stirred for a further 45 minutes. After cooling, the precipitated silver bromide was filtered off and washed with acetic acid. The combined filtrates were partitioned between dichloromethane and water and the aqueous layer was further extracted with dichloromethane. The combined organic extracts were washed with aqueous sodium bisulfite, dried over sodium sulfate, filtered, and evaporated. Acetic acid was then removed by azeotropic distillation with heptane. Distillation of the residue under reduced pressure gave 7.07 g of the title compound, b.p. 82°-84° C. (1 mm). The structural assignment was supported by 1H NMR and 13C NMR.

Workup

  1. additionAfter the addition
  2. stirringthe reaction mixture was stirred for a further 45 minutes
  3. temperatureAfter cooling
  4. filtrationthe precipitated silver bromide was filtered off
  5. washwashed with acetic acid
  6. customThe combined filtrates were partitioned between dichloromethane and water
  7. extractionthe aqueous layer was further extracted with dichloromethane
  8. washThe combined organic extracts were washed with aqueous sodium bisulfite
  9. dry with materialdried over sodium sulfate
  10. filtrationfiltered
  11. customevaporated
  12. customAcetic acid was then removed by azeotropic distillation with heptane
  13. distillationDistillation of the residue under reduced pressure

Sources & evidence

ORD record
ord-bd5fa3d8f0c8482eaec63538bb98e77b
Source dataset
uspto-grants-1995_05
Patent number
US05420343

Reaction notes

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