Sulfuric Acid → 1-Bromo-4-pentylbenzene

HRID 1769562Notes

Reaction equation

HRID 1769562 reaction equation
[CH2:1]([C:6]1[CH:12]=[CH:11][C:9](N)=[CH:8][CH:7]=1)[CH2:2][CH2:3][CH2:4][CH3:5].S(=O)(=O)(O)O.N([O-])=O.[Na+].[Br-:22].[Na+]>O.[Cu].O.O.O.O.O.O.O.S([O-])([O-])=O.[Na+].[Na+]>[CH2:1]([C:6]1[CH:12]=[CH:11][C:9]([Br:22])=[CH:8][CH:7]=1)[CH2:2][CH2:3][CH2:4][CH3:5]

Participants

8

Reactant 4

HCID 1118Sulfuric Acid2×HCID 931624-PentylanilineHCID 253881Sodium BromideHCID 23668193Sodium Nitrite

Product 1

HCID 27355991-Bromo-4-pentylbenzeneYield 44.2%

Reagents, catalysts & solvents 3

HCID 23978CopperCatalystHCID 160916Sodium sulfite heptahydrateCatalystHCID 962WaterSolvent3×

Procedure

A reaction vessel was charged with 100 g of 4-pentylaniline and 600 ml of water, and 80 g of concentrated sulfuric acid was added dropwise with ice water cooling and stirring. A solution of 43 g of sodium nitrite in 80 ml of water was then added dropwise and the reaction was carried out at the same temperature for 2 hours with stirring whereby a diazonium salt solution was prepared. Another reaction vessel was charged with 38.5 g of cupric sulfate pentahydrate (CuSO4.5H2O ), 12.2g of copper powder, 70 g of sodium bromide and 600 ml of water. To the mixture were added at room temperature with stirring 18.5 g of concentrated sulfuric acid and then 4.5 g of sodium sulfite heptahydrate. The temperature of the resultant temperature was allowed to rise, and the previously prepared diazonium salt solution was added dropwise over a period of 1 hour under reflux with stirring, whereafter the mixture was subjected to reaction for a further period of 1 hour. The reaction liquid was cooled and then extracted with 1 l of hexane added. The resultant hexane solution was washed successively with water, aqueous caustic soda and water and then dried over Glauber's salt. The hexane was distilled off and the residue was distilled under reduced pressure to obtain 61.5 g (44%) of 4-pentylbromobenzene (b.p. 135°-142° C./ 15-17 mmHg).

Workup

  1. customwas prepared
  2. additionTo the mixture were added at room temperature
  3. temperatureunder reflux
  4. stirringwith stirring, whereafter the mixture
  5. customwas subjected to reaction for a further period of 1 hour
  6. customThe reaction liquid
  7. temperaturewas cooled
  8. extractionextracted with 1 l of hexane
  9. additionadded
  10. washThe resultant hexane solution was washed successively with water, aqueous caustic soda and water
  11. dry with materialdried over Glauber's salt
  12. distillationThe hexane was distilled off
  13. distillationthe residue was distilled under reduced pressure

Sources & evidence

ORD record
ord-ced22cb20e104c42b3052132f8070d22
Source dataset
uspto-grants-1995_01
Patent number
US05382380

Reaction notes

Loading…