Sulfuric Acid → 3-Acetoxy-5-hydroxybenzoic acid

HRID 2236336

Reaction equation

HRID 2236336 reaction equation
[OH:1][C:2]1[CH:3]=[C:4]([CH:8]=[C:9]([OH:11])[CH:10]=1)[C:5]([OH:7])=[O:6].[OH-].[Na+].[CH3:14][C:15](OC(C)=O)=[O:16].OS(O)(=O)=O>O>[C:15]([O:1][C:2]1[CH:3]=[C:4]([CH:8]=[C:9]([OH:11])[CH:10]=1)[C:5]([OH:7])=[O:6])(=[O:16])[CH3:14]

Participants

6

Reactant 4

HCID 1118Sulfuric AcidHCID 74243,5-Dihydroxybenzoic AcidHCID 7918Acetic AnhydrideHCID 14798Sodium Hydroxide

Product 1

HCID 552778283-Acetoxy-5-hydroxybenzoic acidYield 60.1%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
0 °C

Procedure

To 3,5-dihydroxybenzoic acid (20 g, 129 mmol) was added NaOH (15.6 g, 390 mmol) in 100 mL water. After the mixture was cooled to 0° C., Ac2O (13.2 g, 129 mmol) was added. The solution was stirred for 40 min and then acidified with 10% H2SO4 at 0° C. The precipitate was filtered and washed with cold water. The crude product was recrystallized from water to give 3-acetoxy-5-hydroxybenzoic acid (15.2 g, 60%). Data are: 1H NMR (Aceton-d6, 300 MHz) δ 8.96 (s, 1H), 7.40 (dd, 1H, J=1.5 Hz), 7.26 (dd, 1H, J=1.5 Hz), 6.86 (t, 1H, 2.1H), 2.27 (s, 3H); HRMS (EI+) found 196.0380 M+, calcd 196.0372 for C9H8O5.

Workup

  1. filtrationThe precipitate was filtered
  2. washwashed with cold water
  3. customThe crude product was recrystallized from water

Sources & evidence

ORD record
ord-f167dd5ff69f4b639478e7778f736def
Source dataset
uspto-grants-2010_05
Patent number
US07714161B2

Linked notes

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