Acetic Anhydride → O-acetyl-5-chlorosalicylic acid

HRID 2390600Notes

Reaction equation

HRID 2390600 reaction equation
[Cl:1][C:2]1[CH:10]=[C:6]([C:7]([OH:9])=[O:8])[C:5]([OH:11])=[CH:4][CH:3]=1.[C:12](OC(=O)C)(=[O:14])[CH3:13]>S(=O)(=O)(O)O.Cl>[C:12]([O:8][C:7](=[O:9])[C:6]1[C:5](=[CH:4][CH:3]=[C:2]([Cl:1])[CH:10]=1)[OH:11])(=[O:14])[CH3:13]

Participants

5

Reactant 2

HCID 7918Acetic AnhydrideHCID 94475-Chlorosalicylic Acid

Product 1

HCID 86592304O-acetyl-5-chlorosalicylic acidYield 97%

Reagents, catalysts & solvents 2

HCID 1118Sulfuric AcidCatalystHCID 313Hydrochloric AcidSolvent

Procedure

10 g (57.9 mmol) 5-chlorosalicylic acid was weighed in a 100-mL round-bottomed flask, followed by the addition of acetic anhydride (12.8 mL, 115.9 mmol). The mixture was stirred for 5 minutes before adding concentrated sulfuric acid (2 drops). The reaction was refluxed for 3 hours. Progress of the reaction was monitored by HPLC. The reaction mixture was cooled to room temperature and poured into a beaker containing 2N HCl (200 mL) to precipitate the product out. The product was collected via vacuum filtration. A purity check by HPLC revealed the presence of impurities. The precipitate was stirred in water (150 mL) overnight in a 200-mL round-bottomed flask. The insoluble solid was collected via vacuum filtration. An impurity check by HPLC revealed that the crude product was free of the impurities. The product was dried overnight in vacuo to yield 12 g of O-acetyl-5-chlorosalicylic acid (56 mmol, 97% yield)

Workup

  1. temperatureThe reaction was refluxed for 3 hours
  2. additionpoured into a beaker
  3. customto precipitate the product out
  4. filtrationThe product was collected via vacuum filtration
  5. stirringThe precipitate was stirred in water (150 mL) overnight in a 200-mL round-bottomed flask
  6. filtrationThe insoluble solid was collected via vacuum filtration
  7. customThe product was dried overnight in vacuo

Sources & evidence

ORD record
ord-9998d50599e743dd9e01c872f856eb30
Source dataset
uspto-grants-2012_09
Patent number
US08273794B2

Reaction notes

Loading…