Ethanol → 5-Acetamido-2-bromobenzoic acid

HRID 1634240Notes

Reaction equation

HRID 1634240 reaction equation
[Sn](Cl)Cl.[Br:4][C:5]1[CH:13]=[CH:12][C:11]([N+:14]([O-])=O)=[CH:10][C:6]=1[C:7]([OH:9])=[O:8].[CH2:17]([OH:19])[CH3:18]>>[C:17]([NH:14][C:11]1[CH:12]=[CH:13][C:5]([Br:4])=[C:6]([CH:10]=1)[C:7]([OH:9])=[O:8])(=[O:19])[CH3:18]

Participants

4

Reactant 3

HCID 702EthanolHCID 24479Stannous ChlorideHCID 2430252-Bromo-5-nitrobenzoic acid

Product 1

HCID 27341595-Acetamido-2-bromobenzoic acidYield 96%

Conditions

Temperature
70 °C

Procedure

Tin(II) chloride (46.67 g, 206.84 mmol) was added portionwise to a solution of 2-bromo-5-nitro benzoic acid (12.71 g, 49.9 mmol) in dry ethanol (200 mL). The mixture was heated at 70° C. for 45 min, then ethanol was evaporated. The residue was cooled to 0° C., and acetic anhydride (43 mL) and pyridine (26 mL) were added. The solution was stirred at room temperature for 14 h and evaporated. The residue was partitioned between aq. 2M HCl and ethyl acetate (400 mL). The organic phase was washed with brine and dried over MgSO4. The residue from evaporation was crystallized from water to give 5-acetylamino-2-bromobenzoic acid (12.4 g, 96%).

Workup

  1. customethanol was evaporated
  2. temperatureThe residue was cooled to 0° C.
  3. additionacetic anhydride (43 mL) and pyridine (26 mL) were added
  4. customevaporated
  5. customThe residue was partitioned between aq. 2M HCl and ethyl acetate (400 mL)
  6. washThe organic phase was washed with brine
  7. dry with materialdried over MgSO4
  8. customThe residue from evaporation
  9. customwas crystallized from water

Sources & evidence

ORD record
ord-3621af1e583849ed92e6b779f0861a57
Source dataset
uspto-grants-2003_01
Patent number
US06506769B2

Reaction notes

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