Acetic Acid → Etodolac

HRID 2394817Notes

Reaction equation

HRID 2394817 reaction equation
[CH3:1][CH2:2][C:3]1[C:8]2[NH:9][C:10]3[C@:15]([CH2:18][C:19]([OH:21])=[O:20])([CH2:16][CH3:17])[O:14][CH2:13][CH2:12][C:11]=3[C:7]=2[CH:6]=[CH:5][CH:4]=1.S(=O)(=O)(O)O.C(O)(=O)C>CO>[CH3:1][CH2:2][C:3]1[CH:4]=[CH:5][CH:6]=[C:7]2[C:11]3[CH2:12][CH2:13][O:14][C:15]([CH2:18][C:19]([OH:21])=[O:20])([CH2:16][CH3:17])[C:10]=3[NH:9][C:8]=12

Participants

5

Reactant 3

HCID 176Acetic AcidHCID 1118Sulfuric AcidHCID 667528(-)-Etodolac

Product 1

HCID 3308EtodolacYield 60%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

(R)-Etodolac (1.0 g) is dissolved in methanol (20 ml) and treated with concentrated sulphuric acid (0.06 equiv). The mixture is heated under reflux for 3 days then cooled to ambient temperature. The racemic ester is deposited as a white crystalline solid and collected by filtration (60% yield). The racemic ester is treated with aqueous sodium hydroxide to effect hydrolysis, then acidified with acetic acid to pH 4 to give racemic etodolac as an off-white micro-crystalline powder.

Workup

  1. temperatureThe mixture is heated
  2. temperatureunder reflux for 3 days
  3. filtrationcollected by filtration (60% yield)
  4. additionThe racemic ester is treated with aqueous sodium hydroxide
  5. customhydrolysis

Sources & evidence

ORD record
ord-b494afde0a33439599c227797b79d821
Source dataset
uspto-grants-1998_09
Patent number
US05811558

Reaction notes

Loading…