Cesium carbonate → 3-Ethyl-1-(2-methoxyethyl)-4-nitro-pyrazole-5-carboxamide

HRID 354164Notes

Reaction equation

HRID 354164 reaction equation
[CH2:1]([C:3]1[C:7]([N+:8]([O-:10])=[O:9])=[C:6]([C:11]([NH2:13])=[O:12])[NH:5][N:4]=1)[CH3:2].[CH3:14][O:15][CH2:16][CH2:17]Br.C(=O)([O-])[O-].[Cs+].[Cs+]>CN(C)C=O>[CH2:1]([C:3]1[C:7]([N+:8]([O-:10])=[O:9])=[C:6]([C:11]([NH2:13])=[O:12])[N:5]([CH2:17][CH2:16][O:15][CH3:14])[N:4]=1)[CH3:2]

Participants

5

Reactant 3

HCID 10796Cesium carbonateHCID 809722-Bromoethyl methyl etherHCID 178438045HCID 178438045, compound

Product 1

HCID 235031803-Ethyl-1-(2-methoxyethyl)-4-nitro-pyrazole-5-carboxamideYield 39%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

A mixture of 3-ethyl-4-nitro-1H-pyrazole-5-carboxamide (prepared as in WO 98/49166) (1.7 g, 8.8 mmol), 2-bromoethyl methyl ether (0.85 mL, 8.85 mmol) and cesium carbonate (2.9 g, 9.0 mmol) in dimethylformamide (20 mL) was stirred at room temperature for 20 h. The reaction mixture was concentrated under reduced pressure and the residue was partitioned between ethyl acetate (125 mL) and brine (100 mL). The phases were separated, and the organic layer was dried (Na2SO4), and evaporated under reduced pressure. The crude product was purified by column chromatography on silica gel, using ethyl acetate:methanol (97:3) as eluant to afford 3-ethyl-1-(2-methoxyethyl)-4-nitro-pyrazole-5-carboxamide (831 mg, 39%).

Workup

  1. concentrationThe reaction mixture was concentrated under reduced pressure
  2. customthe residue was partitioned between ethyl acetate (125 mL) and brine (100 mL)
  3. customThe phases were separated
  4. dry with materialthe organic layer was dried (Na2SO4)
  5. customevaporated under reduced pressure
  6. customThe crude product was purified by column chromatography on silica gel

Sources & evidence

ORD record
ord-827cf19c96204ef097dd2721a11b5e1c
Source dataset
uspto-grants-2004_06
Patent number
US06756373B1

Reaction notes

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