Hydrochloric Acid → 3-Amino-5-(pyridin-4-yl)thiophene-2-carboxylic acid

HRID 2363921Notes

Reaction equation

HRID 2363921 reaction equation
[NH2:1][C:2]1[CH:6]=[C:5]([C:7]2[CH:12]=[CH:11][N:10]=[CH:9][CH:8]=2)[S:4][C:3]=1[C:13]([O:15]C)=[O:14].C[O-].[Na+].CO.Cl>O>[NH2:1][C:2]1[CH:6]=[C:5]([C:7]2[CH:8]=[CH:9][N:10]=[CH:11][CH:12]=2)[S:4][C:3]=1[C:13]([OH:15])=[O:14]

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 887MethanolHCID 10942334Sodium MethoxideHCID 43155531Methyl 3-amino-5-(pyridin-4-yl)thiophene-2-carboxylate

Product 1

HCID 130923543-Amino-5-(pyridin-4-yl)thiophene-2-carboxylic acidYield 92%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

A mixture of methyl 3-amino-5-(pyridin-4-yl)thiophene-2-carboxylate (2.34 g, 10 mmol), sodium methoxide (1.62 g, 30 mmol), methanol (40 mL) and water (10 mL) was refluxed for 4 h. The mixture was allowed to cool to room temperature and stirring was continued overnight. The mixture was cooled under ice-bath, then conc. HCl (2.48 mL, 30 mmol) was added (pH was approx. 4). The resultant yellow precipitate was collected by filtration and washed with water and methanol to afford the title compound (2.02 g, 92%) as a yellow solid:

Workup

  1. temperaturewas refluxed for 4 h
  2. temperatureThe mixture was cooled under ice-bath
  3. filtrationThe resultant yellow precipitate was collected by filtration
  4. washwashed with water and methanol

Sources & evidence

ORD record
ord-409acc18e6524910b87314263f262eb3
Source dataset
uspto-grants-2014_04
Patent number
US08691828B2

Reaction notes

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