Dimethyl Sulfate → 5-Bromo-2-methoxybenzoic acid

HRID 1447125Notes

Reaction equation

HRID 1447125 reaction equation
[Br:1][C:2]1[CH:10]=[C:6]([C:7]([OH:9])=[O:8])[C:5]([OH:11])=[CH:4][CH:3]=1.[OH-].[Na+].S(OC)(O[CH3:18])(=O)=O>O>[Br:1][C:2]1[CH:3]=[CH:4][C:5]([O:11][CH3:18])=[C:6]([CH:10]=1)[C:7]([OH:9])=[O:8]

Participants

5

Reactant 3

HCID 6497Dimethyl Sulfate2×HCID 69725-Bromosalicylic acidHCID 14798Sodium Hydroxide2×

Product 1

HCID 8817395-Bromo-2-methoxybenzoic acid

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

The starting material is prepared as follows: The solution of 110 g of 5-bromosalicylic acid in 900 ml of water and 48 g of sodium hydroxide is stirred while 60 ml of dimethyl sulfate are added. The mixture is stirred at 70° for 3 hours, whereupon 50 ml of 50% aqueous sodium hydroxide are added, followed slowly by 60 ml of dimethyl sulfate. After stirring at 70° for 6 hours the last step is repeated and the mixture warmed 17 hours longer. It is cooled in an ice bath, filtered, the filtrate stirred with methylene chloride and neutralized with cold 5 N aqueous hydrochloric acid. The organic phase is separated, dried and evaporated to yield the 5-bromo-2-methoxybenzoic acid melting at 115°-117°.

Workup

  1. customThe starting material is prepared
  2. additionare added
  3. additionare added
  4. temperaturethe mixture warmed 17 hours longer
  5. temperatureIt is cooled in an ice bath
  6. filtrationfiltered
  7. stirringthe filtrate stirred with methylene chloride and neutralized with cold 5 N aqueous hydrochloric acid
  8. customThe organic phase is separated
  9. customdried
  10. customevaporated

Sources & evidence

ORD record
ord-cb176baee110435e8217c2e602d25939
Source dataset
uspto-grants-1982_02
Patent number
US04315926

Reaction notes

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