Methanol → Methyl 5-amino-6-chloro-2-methylimidazo[1,2-a]pyridine-8-carboxylic acid

HRID 1168271Notes

Reaction equation

HRID 1168271 reaction equation
[NH2:1][C:2]1[N:7]2[CH:8]=[C:9]([CH3:11])[N:10]=[C:6]2[C:5]([C:12]([O:14]C)=[O:13])=[CH:4][C:3]=1[Cl:16].[OH-].[Li+].[CH3:19]O>>[CH3:19][C:8]1[N:7]2[C:2]([NH2:1])=[C:3]([Cl:16])[CH:4]=[C:5]([C:12]([OH:14])=[O:13])[C:6]2=[N:10][C:9]=1[CH3:11]

Participants

4

Reactant 3

HCID 887MethanolHCID 3939Lithium HydroxideHCID 12088096Methyl 5-amino-6-chloro-2-methylimidazo[1,2-a]pyridine-8-carboxylate

Product 1

HCID 67550158Methyl 5-amino-6-chloro-2-methylimidazo[1,2-a]pyridine-8-carboxylic acidYield 96%

Procedure

A mixture of methyl 5-Amino-6-chloro-2-methylimidazo[1,2-a]pyridine-8-carboxylate (EXAMPLE 26, Step 4, 10.5 g, 43.9 mmol,) and 1 N lithium hydroxide (87.7 mL, 87.7 mmol) in methanol (100 mL) was stirred under reflux for 1 h. After removal of the solvent in vacuo, the residue was suspended with water and treated with 2 N hydrochloric acid to adjust to pH 4. The resulting solid was filtered, washed with water and diethyl ether and dried in vacuo with heating to give 9.5 g (42.2 mmol, 96%) of the title compound as a brown solid.

Workup

  1. temperatureunder reflux for 1 h
  2. customAfter removal of the solvent in vacuo
  3. additiontreated with 2 N hydrochloric acid
  4. filtrationThe resulting solid was filtered
  5. washwashed with water and diethyl ether
  6. customdried in vacuo
  7. temperaturewith heating

Sources & evidence

ORD record
ord-a9181864569a426e896616b8feaae84b
Source dataset
uspto-grants-2003_09
Patent number
US06624162B2

Reaction notes

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