Potassium Hydroxide → Desethyl KB 3022

HRID 542862Notes

Reaction equation

HRID 542862 reaction equation
[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6]([C:9]2[N:10]=[C:11]([C:22]3[N:23]([CH2:27][C:28]([O:30]CC)=[O:29])[CH:24]=[CH:25][CH:26]=3)[S:12][C:13]=2[C:14]2[CH:19]=[CH:18][C:17]([O:20][CH3:21])=[CH:16][CH:15]=2)=[CH:5][CH:4]=1.[OH-].[K+]>C(O)C>[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6]([C:9]2[N:10]=[C:11]([C:22]3[N:23]([CH2:27][C:28]([OH:30])=[O:29])[CH:24]=[CH:25][CH:26]=3)[S:12][C:13]=2[C:14]2[CH:15]=[CH:16][C:17]([O:20][CH3:21])=[CH:18][CH:19]=2)=[CH:5][CH:4]=1

Participants

4

Reactant 2

HCID 14797Potassium HydroxideHCID 65870Pamicogrel

Product 1

HCID 127736Desethyl KB 3022Yield 80%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

Ethyl 2-[4,5-bis(4-methoxyphenyl)thiazol-2-yl]-pyrrole-1-acetate (prepared in Example 14) (3.59 g, 8 mmole) and potassium hydroxide (0.90 g, 16 mmoles) are added to ethanol (80 ml), and the mixture is refluxed for 5 minutes. After distilling off ethanol, the resulting residue is dissolved in water. To the aqueous solution is added 10% hydrochloric acid, and the precipitated crystals are separated by filtration and dried to give crude crystals (3.20 g). The crude crystals are recrystallized from benzene to give 2-[4,5-bis(4-methoxyphenyl)thiazol-2-yl]-pyrrole-1-acetic acid (2.69 g, yield: 80%).

Workup

  1. temperaturethe mixture is refluxed for 5 minutes
  2. distillationAfter distilling off ethanol
  3. dissolutionthe resulting residue is dissolved in water
  4. additionTo the aqueous solution is added 10% hydrochloric acid
  5. customthe precipitated crystals are separated by filtration
  6. customdried
  7. customto give crude crystals (3.20 g)
  8. customThe crude crystals are recrystallized from benzene

Sources & evidence

ORD record
ord-4b15a582eb404bcb87f432f24055e2d1
Source dataset
uspto-grants-1987_04
Patent number
US04659726

Reaction notes

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