Water → methyl 3-chloro-1-(pyridin-3-yl)-1H-pyrazole-5-carboxylate

HRID 512731Notes

Reaction equation

HRID 512731 reaction equation
[Cl:1][C:2]1[CH2:6][CH:5]([C:7]([O:9][CH3:10])=[O:8])[N:4]([C:11]2[CH:12]=[N:13][CH:14]=[CH:15][CH:16]=2)[N:3]=1.O.[N+]([O-])([O-])=O.[Ce+4].[NH4+].[NH4+].[N+]([O-])([O-])=O.[N+]([O-])([O-])=O.[N+]([O-])([O-])=O.[N+]([O-])([O-])=O.[N+]([O-])([O-])=O>O1CCCC1>[Cl:1][C:2]1[CH:6]=[C:5]([C:7]([O:9][CH3:10])=[O:8])[N:4]([C:11]2[CH:12]=[N:13][CH:14]=[CH:15][CH:16]=2)[N:3]=1

Participants

5

Reactant 3

HCID 962WaterHCID 180504Ceric ammonium nitrateHCID 118022669Methyl 3-chloro-1-(pyridine-3-yl)-4,5-dihydro-1H-pyrazole-5-carboxylate

Product 1

HCID 118022666methyl 3-chloro-1-(pyridin-3-yl)-1H-pyrazole-5-carboxylateYield 57.4%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

Methyl 3-chloro-1-(pyridine-3-yl)-4,5-dihydro-1H-pyrazole-5-carboxylate (2.63 g, 11.0 mmol) was stirred in tetrahydrofuran (50 mL) and water (50 mL) at 0° C. diammonium cerium (IV) nitrate (15.0 g, 27.4 mmol) was added in portions and the reaction was stirred at room temperature for 18 hours. thin layer chromatography analysis indicated that the starting material was consumed. The mixture was extracted with ethyl acetate (2×300 mL) and the organic layers were dried and concentrated. The residue was purified by flash column chromatography using 50-100% ethyl acetate/hexanes as eluent. The pure fractions were concentrated to provide the desired product as a yellow solid (1.50 g, 52%): mp 99-102° C.; 1H NMR (400 MHz, DMSO-d6) δ 9.00 (dd, J=2.5, 0.7 Hz, 1H), 8.83 (dd, J=5.2, 1.5 Hz, 1H), 8.35 (ddd, J=8.3, 2.5, 1.4 Hz, 1H), 7.83 (ddd, J=8.3, 5.2, 0.7 Hz, 1H), 7.35 (s, 1H), 3.78 (s, 3H); 13C NMR (101 MHz, CDCl3) δ 158.34, 149.90, 146.89, 141.39, 136.09, 134.77, 133.30, 123.14, 112.01, 52.53; ESIMS m/z 238 ([M+H]+).

Workup

  1. customwas consumed
  2. extractionThe mixture was extracted with ethyl acetate (2×300 mL)
  3. customthe organic layers were dried
  4. concentrationconcentrated
  5. customThe residue was purified by flash column chromatography
  6. concentrationThe pure fractions were concentrated

Sources & evidence

ORD record
ord-8ec97979d6724d39840fcea7772fc3a3
Source dataset
uspto-grants-2015_08
Patent number
US09102654B2

Reaction notes

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