Sulfuric Acid → 2,5-Dibromophenol

HRID 1415481

Reaction equation

HRID 1415481 reaction equation
[Br:1][C:2]1[CH:8]=[CH:7][C:6]([Br:9])=[CH:5][C:3]=1N.S(=O)(=O)(O)[OH:11].S(O)(O)(=O)=O.BrC1C=CC(Br)=CC=1N>C1(C)C(C)=CC=CC=1>[Br:1][C:2]1[CH:8]=[CH:7][C:6]([Br:9])=[CH:5][C:3]=1[OH:11]

Participants

5

Reactant 3

HCID 1118Sulfuric AcidHCID 771982,5-DibromoanilineHCID 706346722,5-Dibromoaniline sulfate

Product 1

HCID 341772,5-Dibromophenol

Reagents, catalysts & solvents 1

HCID 7237O-XyleneSolvent2×

Procedure

61.6 Grams of 2,5-dibromoaniline and 250 g of 75% aqueous sulfuric acid solution were charged into a ceramic ball mill having one liter capacity. A suspension of fine particles of 2,5-dibromoaniline sulfate was prepared by a method similar to that described in Example 5. The suspension was transferred into a beaker having one liter capacity. The ceramic ball mill used was washed with 120 g of 75% aqueous sulfuric acid solution and the washings were transferred into the beaker. Diazotization of 2,5-dibromoaniline sulfate in the form of suspension of fine particles was carried out by a method similar to that described in Example 5 except that 18.2 g of sodium nitrite powder was added. Hydrolysis of 2,5-dibromobenzenediazonium sulfate was carried out by a method similar to that described in Example 5. A xylene layer was isolated from the hydrolyzed product and a crude product of 2,5-dibromophenol was obtained after the xylene was removed by distillation. The crude product of 2,5-dibromophenol was steam distilled by introducing superheated steam. After the distillate was cooled, crystallized 2,5-dibromophenol thus formed was obtained by filtration and dried. 47.3 Grams of 2,5-dibromophenol having melting point of 71°-74° C was obtained. The yield was found to be 85.0%.

Workup

  1. customwas prepared by a method similar to
  2. washThe ceramic ball mill used was washed with 120 g of 75% aqueous sulfuric acid solution
  3. additionDiazotization of 2,5-dibromoaniline sulfate in the form of suspension of fine particles
  4. additionwas added
  5. customHydrolysis of 2,5-dibromobenzenediazonium sulfate

Sources & evidence

ORD record
ord-4421d2eb7adb4dc38cf01a68c433cc14
Source dataset
uspto-grants-1977_01
Patent number
US04005151

Linked notes

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