Sulfuric Acid → 3-Bromo-2-(difluoromethoxy)aniline

HRID 429596Notes

Reaction equation

HRID 429596 reaction equation
S(=O)(=O)(O)O.[Br:6][C:7]1[C:8]([O:16][CH:17]([F:19])[F:18])=[C:9]([N+:13]([O-])=O)[CH:10]=[CH:11][CH:12]=1>[Fe].O>[Br:6][C:7]1[C:8]([O:16][CH:17]([F:18])[F:19])=[C:9]([CH:10]=[CH:11][CH:12]=1)[NH2:13]

Participants

5

Reactant 2

HCID 1118Sulfuric AcidHCID 158867431-Bromo-2-(difluoromethoxy)-3-nitrobenzene

Product 1

HCID 158867443-Bromo-2-(difluoromethoxy)anilineYield 72.4%

Reagents, catalysts & solvents 2

HCID 23925IronCatalystHCID 962WaterSolvent2×

Conditions

Temperature
80 °C

Procedure

Into a 300-ml four-necked flask provided with a reflux condenser, a stirrer and a thermometer were fed 6.56 g of an iron powder, 0.49 g (4.7 mmol) of 95% sulfuric acid and 50 ml of water. The mixture was heated to 80° C. on an oil bath. Thereto was slowly added, at 80 to 85° C., 12.54 g (0.047 mol) of 3-bromo-2-difluoromethoxynitrobenzene. The temperature was increased and refluxing was conducted at 100° C. for 2 hours with heating. After completion of the reaction, azeotropic distillation was performed while 200 ml of water was added gradually. The distillate was subjected to extraction two times each using 30 ml of dichloromethane. The organic layer was dried over anhydrous sodium sulfate and subjected to distillation to remove the solvent and obtain 8.09 g of 3-bromo-2-difluoromethoxyaniline (yield: 72.4%, purity: 99.7%).

Workup

  1. customInto a 300-ml four-necked flask provided with a reflux condenser, a stirrer
  2. additionThereto was slowly added, at 80 to 85° C.
  3. temperatureThe temperature was increased
  4. temperaturerefluxing
  5. temperaturewith heating
  6. customAfter completion of the reaction, azeotropic distillation
  7. additionwas added gradually
  8. extractionThe distillate was subjected to extraction two times each using 30 ml of dichloromethane
  9. dry with materialThe organic layer was dried over anhydrous sodium sulfate
  10. distillationsubjected to distillation
  11. customto remove the solvent

Sources & evidence

ORD record
ord-86450856e2b944818644b6e30d52c131
Source dataset
uspto-grants-2001_11
Patent number
US06316658B1

Reaction notes

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