4-Amino-3-nitrobenzonitrile → 3,4-Diaminobenzonitrile

HRID 1637699Notes

Reaction equation

HRID 1637699 reaction equation
[NH2:1][C:2]1[CH:9]=[CH:8][C:5]([C:6]#[N:7])=[CH:4][C:3]=1[N+:10]([O-])=O.[H][H]>CO.[Pd]>[NH2:10][C:3]1[CH:4]=[C:5]([CH:8]=[CH:9][C:2]=1[NH2:1])[C:6]#[N:7]

Participants

5

Reactant 2

HCID 5959014-Amino-3-nitrobenzonitrileHCID 178418361HCID 178418361, compound

Product 1

HCID 7372853,4-DiaminobenzonitrileYield 90.1%

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 887MethanolSolvent

Procedure

A solution of 4-amino-3-nitrobenzonitrile (20 mmol) in MeOH (300 mL) in the presence of 5% of Pd/C (1 g) was treated with hydrogen at room temperature for 16 hours. The reaction mixture was filtered and concentrated to give 3,4-diaminobenzonitrile (2.4 g, 90% of yield), which was directly treated with formic acid (20 mL) under reflux for 4 hours. After removal of the excess formic acid, the residue was dissolved in EtOAc, washed with 10% sodium bicarbonate and brine, and dried over MgSO4. Concentration gave 5-cyanobenzimidazole (2.2 g, 85%). 1H NMR (CD3OD) δ8.39 (s, 1H), 8.05 (s, 1H), 7.76 (d, J=8.4 Hz, 1H), 7.59 (dd, J=8.4 Hz, J=1.1 Hz, 1H); MS: 144 (M+H)+.

Workup

  1. filtrationThe reaction mixture was filtered
  2. concentrationconcentrated

Sources & evidence

ORD record
ord-1052122c2b4342b4919e71b81cca0d24
Source dataset
uspto-grants-2000_03
Patent number
US06043257

Reaction notes

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