Sulfuric Acid → {2-[2-(3-Chloro-phenyl)-3-cyclopentyl-propionylamino]-thiazol-4-yl}-acetic acid methyl ester

HRID 398463Notes

Reaction equation

HRID 398463 reaction equation
[CH2:1]([O:3][C:4](=[O:28])[CH2:5][C:6]1[N:7]=[C:8]([NH:11][C:12](=[O:27])[CH:13]([C:20]2[CH:25]=[CH:24][CH:23]=[C:22]([Cl:26])[CH:21]=2)[CH2:14][CH:15]2[CH2:19][CH2:18][CH2:17][CH2:16]2)[S:9][CH:10]=1)C.S(=O)(=O)(O)O>CO>[CH3:1][O:3][C:4](=[O:28])[CH2:5][C:6]1[N:7]=[C:8]([NH:11][C:12](=[O:27])[CH:13]([C:20]2[CH:25]=[CH:24][CH:23]=[C:22]([Cl:26])[CH:21]=2)[CH2:14][CH:15]2[CH2:16][CH2:17][CH2:18][CH2:19]2)[S:9][CH:10]=1

Participants

4

Reactant 2

HCID 1118Sulfuric AcidHCID 23394572{2-[2-(3-Chloro-phenyl)-3-cyclopentyl-propionylamino]-thiazol-4-yl}-acetic acid ethyl ester

Product 1

HCID 20707087{2-[2-(3-Chloro-phenyl)-3-cyclopentyl-propionylamino]-thiazol-4-yl}-acetic acid methyl esterYield 61.1%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A solution of {2-[2-(3-chloro-phenyl)-3-cyclopentyl-propionylamino]-thiazol-4-yl}-acetic acid ethyl ester (prepared as in Example 28A, 177.2 mg, 0.42 mmol) in methanol (15 mL) was treated with a catalytic amount of sulfuric acid. The reaction mixture was heated under reflux for 40 h. The reaction was then concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 230-400 mesh, 70/30 hexanes/ethyl acetate) afforded {2-[2-(3-chloro-phenyl)-3-cyclopentyl-propionylamino]-thiazol-4-yl }-acetic acid methyl ester (104.4 mg, 60.9%) as a clear oil: EI-HRMS m/e calcd for C20H23ClN2O3S (M+) 406.1117, found 406.1118.

Workup

  1. temperatureThe reaction mixture was heated
  2. temperatureunder reflux for 40 h
  3. concentrationThe reaction was then concentrated in vacuo

Sources & evidence

ORD record
ord-0055307293ef410293e899be6c8a0884
Source dataset
uspto-grants-2003_08
Patent number
US06610846B1

Reaction notes

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