4-Hydroxybenzoic Acid → Benzoic acid, 4-(acetyloxy)-

HRID 326393Notes

Reaction equation

HRID 326393 reaction equation
[OH:1][C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[CH:4][CH:3]=1.[OH-].[Na+].[C:13](OC(=O)C)(=[O:15])[CH3:14].Cl>O>[C:13]([O:1][C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[CH:4][CH:3]=1)(=[O:15])[CH3:14]

Participants

6

Conditions

Temperature
0 °C

Procedure

An amount of 4-hydroxybenzoic acid (92.1 grams (g), 0.67 mole) was dissolved in a solution of sodium hydroxide (NaOH) (53.4 g, 1.33 moles) and 1.33 liters (L) of water in a 4 L beaker. The solution was stirred and cooled to a temperature of 0° C. by adding crushed ice, then acetic anhydride (102.1 g, 1.00 mole) was added. The temperature was maintained at -2° C. for 1 hour by adding one kilogram (kg) of crushed ice. A solution of concentrated hydrochloric acid (HCl) (144.7 g, 1.42 moles) in 267 milliliters (ml) of water was added. The slurry was stirred briefly and filtered. The product was washed twice by stirring it with 2 L portions of fresh water then filtered and dried in a vacuum oven at 80° C. for 16 hours. After recrystallization from methyl isobutyl ketone, the product consisted of 111 g of white crystals with a melting point (m.p.) of 192° C. to 192.5° C.

Workup

  1. additionby adding
  2. customcrushed ice
  3. temperatureThe temperature was maintained at -2° C. for 1 hour
  4. stirringThe slurry was stirred briefly
  5. filtrationfiltered
  6. washThe product was washed twice
  7. stirringby stirring it with 2 L portions of fresh water
  8. filtrationthen filtered
  9. customdried in a vacuum oven at 80° C. for 16 hours
  10. customAfter recrystallization from methyl isobutyl ketone
  11. customconsisted of 111 g of white crystals with a melting point (m.p.) of 192° C. to 192.5° C.

Sources & evidence

ORD record
ord-77cd6834bcb3437d82bb823797513968
Source dataset
uspto-grants-1993_12
Patent number
US05268443

Reaction notes

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