Acetic Acid → Methyl 4-amino-5-cyanothiophene-2-carboxylate

HRID 1723918Notes

Reaction equation

HRID 1723918 reaction equation
[C:1]([C:3]1[S:7][C:6]([C:8]([O:10][CH3:11])=[O:9])=[CH:5][C:4]=1[N+:12]([O-])=O)#[N:2].C(O)(=O)C>[Fe]>[NH2:12][C:4]1[CH:5]=[C:6]([C:8]([O:10][CH3:11])=[O:9])[S:7][C:3]=1[C:1]#[N:2]

Participants

4

Reactant 2

HCID 176Acetic AcidHCID 68828210Methyl 5-cyano-4-nitrothiophene-2-carboxylate

Product 1

HCID 68825738Methyl 4-amino-5-cyanothiophene-2-carboxylateYield 69.1%

Reagents, catalysts & solvents 1

HCID 23925IronCatalyst

Procedure

A suspension of methyl 5-cyano-4-nitro-thiophene-2-carboxylate (0.17 mol, 36 g) and iron powder (0.51 mol, 28.5 g) in glacial acetic acid 68 mL (1.2 mol) was refluxed for 3 hours. The crude was concentrated under vacuum and neutralized with diluted ammonia. The aqueous layer was extracted with ethyl acetate (3×250 mL) and dried over Na2SO4. The filtrate was evaporated to dryness to give a yellow solid, which was purified by flash chromatography over silica gel using hexane/ethyl acetate (38:12) as eluent, to afford the title compound as a yellow solid (21.4 g, 69%).

Workup

  1. temperaturewas refluxed for 3 hours
  2. concentrationThe crude was concentrated under vacuum
  3. extractionThe aqueous layer was extracted with ethyl acetate (3×250 mL)
  4. dry with materialdried over Na2SO4
  5. customThe filtrate was evaporated to dryness
  6. customto give a yellow solid, which
  7. customwas purified by flash chromatography over silica gel

Sources & evidence

ORD record
ord-5c28c11ec9fd47ba8a517eb4e48d4154
Source dataset
uspto-grants-2009_02
Patent number
US07485661B2

Reaction notes

Loading…