Potassium Hydroxide → 3-chloro-1-(pyridin-3-yl)-1H-pyrazol-4-amine

HRID 1428339Notes

Reaction equation

HRID 1428339 reaction equation
[Cl:1][C:2]1[C:6]([N+:7]([O-])=O)=[CH:5][N:4]([C:10]2[CH:11]=[N:12][CH:13]=[CH:14][CH:15]=2)[N:3]=1.[OH-].[K+]>C(O)(=O)C.C(O)C.O.[Fe]>[Cl:1][C:2]1[C:6]([NH2:7])=[CH:5][N:4]([C:10]2[CH:11]=[N:12][CH:13]=[CH:14][CH:15]=2)[N:3]=1

Participants

7

Reactant 2

HCID 14797Potassium HydroxideHCID 675001483-(3-chloro-4-nitro-1H-pyrazol-1-yl)pyridine

Product 1

HCID 674993943-chloro-1-(pyridin-3-yl)-1H-pyrazol-4-amineYield 80.2%

Reagents, catalysts & solvents 4

HCID 23925IronCatalystHCID 176Acetic AcidSolventHCID 702EthanolSolventHCID 962WaterSolvent

Procedure

To 3-(3-chloro-4-nitro-1H-pyrazol-1-yl)pyridine (0.95 g, 4.23 mmol) in acetic acid (8.46 mL), ethanol (8.46 mL) and water (4.23 mL) was added iron powder (1.18 g, 21.15 mmol) and the reaction was stirred at room temperature for 30 minutes. To this was added carefully 2 M KOH and extracted with ethyl acetate. The ethyl acetate layers were combined, dried (MgSO4), filtered and concentrated to dryness. The crude material was purified by silica gel chromatography (0-10% methanol/dichloromethane) to give the desired product as a white solid (0.66 g, 80%): 1H NMR (400 MHz, CDCl3) δ 8.84 (d, J=2.6 Hz, 1H), 8.49 (dd, J=4.7, 1.4 Hz, 1H), 7.95 (ddd, J=8.3, 2.7, 1.5 Hz, 1H), 7.53 (s, 1H), 7.37 (ddd, J=8.4, 4.7, 0.6 Hz, 1H), 3.17 (bs, 2H).

Workup

  1. extractionextracted with ethyl acetate
  2. dry with materialdried (MgSO4)
  3. filtrationfiltered
  4. concentrationconcentrated to dryness
  5. customThe crude material was purified by silica gel chromatography (0-10% methanol/dichloromethane)

Sources & evidence

ORD record
ord-03f463461199412ab1bb5c234da0c55f
Source dataset
uspto-grants-2015_01
Patent number
US08937083B2

Reaction notes

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