3,4-Diaminopyridine → HCID 178470165, compound

HRID 412704Notes

Reaction equation

HRID 412704 reaction equation
[NH2:1][C:2]1[CH:3]=[N:4][CH:5]=[CH:6][C:7]=1[NH2:8].Cl.C(ONC([CH:16](C)[C:17]([O:19][CH2:20][CH3:21])=[O:18])=N)C>C(O)(=O)C>[NH:8]1[C:7]2[CH:6]=[CH:5][N:4]=[CH:3][C:2]=2[N:1]=[C:16]1[C:17]([O:19][CH2:20][CH3:21])=[O:18]

Participants

4

Reactant 2

HCID 59183,4-DiaminopyridineHCID 178475100HCID 178475100, compound

Product 1

HCID 178470165HCID 178470165, compoundYield 68.7%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Conditions

Temperature
120 °C

Procedure

A mixture comprising 3,4-diaminopyridine (51.7 g, 0.46 mol), ethyl 2-(N-ethoxyamidino)propionoate hydrochloride (125 g, 0.69 mol) and glacial acetic acid (200 mL) was heated at 85° C. and stirred for 18 hours and then heated at 120° C. and stirred for an additional hour. The mixture was cooled to room temperature and concentrated in vacuo. The residue was neutralized by addition of an excess of 5M aqueous ammonium hydroxide and the mixture was extracted with ethyl acetate. The organic layer was washed with saturated aqueous sodium hydrogen carbonate and then saturated aqueous sodium chloride, dried (MgSO4), filtered and concentrated in vacuo to provide ethyl 1H-imidazo[4,5-c]pyridine-2-carboxylate (60.4 g, 58% yield); 1H NMR (300 MHz, CDCl3): 9.00 (s, 1H), 8.45 (d, 1H), 7.50 (d, 1H), 4.25 (q, 2H), 3.90 (q, 1H), 1.75 (d, 3H), 1.25 (tr, 3H).

Workup

  1. stirringstirred for an additional hour
  2. temperatureThe mixture was cooled to room temperature
  3. concentrationconcentrated in vacuo
  4. additionThe residue was neutralized by addition of an excess of 5M aqueous ammonium hydroxide
  5. extractionthe mixture was extracted with ethyl acetate
  6. washThe organic layer was washed with saturated aqueous sodium hydrogen carbonate
  7. dry with materialsaturated aqueous sodium chloride, dried (MgSO4)
  8. filtrationfiltered
  9. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-2d3a5017435243178d466a5cf4f723a0
Source dataset
uspto-grants-2003_05
Patent number
US06562854B2

Reaction notes

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