Methyl 5-methyl-4-nitrothiophene-2-carboxylate → Methyl 4-amino-5-methylthiophene-2-carboxylate

HRID 583776Notes

Reaction equation

HRID 583776 reaction equation
[CH3:1][O:2][C:3]([C:5]1[S:6][C:7]([CH3:13])=[C:8]([N+:10]([O-])=O)[CH:9]=1)=[O:4]>CO.[Ni]>[CH3:1][O:2][C:3]([C:5]1[S:6][C:7]([CH3:13])=[C:8]([NH2:10])[CH:9]=1)=[O:4]

Participants

4

Reactant 1

HCID 268679Methyl 5-methyl-4-nitrothiophene-2-carboxylate

Product 1

HCID 59640747Methyl 4-amino-5-methylthiophene-2-carboxylateYield 98.4%

Reagents, catalysts & solvents 2

HCID 935NickelCatalystHCID 887MethanolSolvent

Procedure

Sponge nickel (1.0 g water wet) was added to a solution of 5-methyl-4-nitro-thiophene-2-carboxylic acid methyl ester (1.79 g, 8.9 mmol) in methanol (50 mL), and the mixture was hydrogenated at room temperature under a hydrogen atmosphere at a starting pressure of 50 psi. After a reaction time of 25 hours, the pressure was released and the mixture filtered. The slurry was rinsed with methanol, and the filtrate was stripped of solvent under reduced pressure to afford 1.5 g of 5-methyl-4-amino-thiophene-2-carboxylic acid methyl ester. A sample was dissolved in ethyl acetate and filtered through a short column of silica gel. Evaporation of the effluent under reduced pressure gave product with a mp 90-91° C.

Workup

  1. customwas hydrogenated at room temperature under a hydrogen atmosphere at a starting pressure of 50 psi
  2. customAfter a reaction time of 25 hours
  3. filtrationthe mixture filtered
  4. washThe slurry was rinsed with methanol

Sources & evidence

ORD record
ord-4d3ee278269f4bf1be27584f87aace42
Source dataset
uspto-grants-2005_08
Patent number
US06924276B2

Reaction notes

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