4-Hydrazinobenzoic acid → 4-(3-oxo-1,3-dihydro-2H-pyrazolo[4,3-c]cinnolin-2-yl)benzoic acid

HRID 1875467Notes

Reaction equation

HRID 1875467 reaction equation
[NH:1]([C:3]1[CH:11]=[CH:10][C:6]([C:7]([OH:9])=[O:8])=[CH:5][CH:4]=1)[NH2:2].Cl[C:13]1[C:22]2[C:17](=[CH:18][CH:19]=[CH:20][CH:21]=2)[N:16]=[N:15][C:14]=1[C:23](OC)=[O:24]>C(O)C>[O:24]=[C:23]1[C:14]2[N:15]=[N:16][C:17]3[CH:18]=[CH:19][CH:20]=[CH:21][C:22]=3[C:13]=2[NH:2][N:1]1[C:3]1[CH:4]=[CH:5][C:6]([C:7]([OH:9])=[O:8])=[CH:10][CH:11]=1

Participants

4

Conditions

Temperature
47.5 °C

Procedure

4-Hydrazinobenzoic acid (68.4 mg, 0.45 mmol) was mixed at room temperature with ethanol (5 ml) to give a crème-coloured suspension. Methyl 4-chlorocinnoline-3-carboxylate (100 mg, 0.45 mmol) was added and the mixture was heated to 45-50° C. for 1 h. The reaction mixture was cooled to room temperature and the solvent was removed under vacuum. Ethyl acetate (10 ml) was added to the residue. The mixture was stirred at room temperature for 1 h. The solids were collected by filtration and dried under vacuum. The title compound was isolated as a brown powder (120 mg, 0.39 mmol, 86%). LCMS: m/z 307 [M+H]+. NMR [DMSO-d6]: δ=7.69-7.77 (m, 1Haryl); 7.81-7.90 (m, 2Haryl); 8.05 (d, J=8.85, 2Haryl); 8.20 (d, J=7.92 Hz, 1Haryl); 8.33 (d, J=8.85 Hz, 2Haryl); 14.64 (s, NH).

Workup

  1. customto give a crème-coloured suspension
  2. temperatureThe reaction mixture was cooled to room temperature
  3. customthe solvent was removed under vacuum
  4. additionEthyl acetate (10 ml) was added to the residue
  5. filtrationThe solids were collected by filtration
  6. customdried under vacuum

Sources & evidence

ORD record
ord-ae32647676d9403896fefc92a0f0c1a8
Source dataset
uspto-grants-2012_11
Patent number
US08309552B2

Reaction notes

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