Sulfuric acid magnesium salt (1:1) → 1-(2-Methoxyethyl)-N-methyl-4-nitro-1H-pyrazole-3-carboxamide

HRID 467645Notes

Reaction equation

HRID 467645 reaction equation
Cl.[CH3:2][NH2:3].C[Al](C)C.C(OC([C:13]1[N:14]([CH2:21][CH2:22][O:23][CH3:24])[N:15]=[CH:16][C:17]=1[N+:18]([O-:20])=[O:19])=O)C.[O-]S([O-])(=O)=O.[Mg+2].[O:31]1[CH2:36]COCC1>O>[CH3:2][NH:3][C:36]([C:16]1[C:17]([N+:18]([O-:20])=[O:19])=[CH:13][N:14]([CH2:21][CH2:22][O:23][CH3:24])[N:15]=1)=[O:31]

Participants

7

Reactant 5

HCID 24083Sulfuric acid magnesium salt (1:1)HCID 312751,4-DioxaneHCID 6364545Methylamine hydrochlorideHCID 16682925TrimethylaluminumHCID 700981462-(2-methoxyethyl)-4-nitro-2H-pyrazole-3-carboxylic acid ethyl ester

Product 1

HCID 701152111-(2-Methoxyethyl)-N-methyl-4-nitro-1H-pyrazole-3-carboxamideYield 16%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

To a solution of methylamine hydrochloride (2.0 g, 25 mmol) at rt in dioxane (60 ml) was added trimethyaluminium (2 M in toluene, 12.3 ml, 25 mmol) and stirred for 2 hrs at rt. Then 1-(2-methoxyethyl)-4-nitro-1H-pyrazole-3-carboxylic acid ethyl ester (2.0 g, 8.0 mmol; example 4, step 2) was added. The mixture was heated to 100° C. and stirring was continued overnight. The mixture was cooled to rt, then 2 ml water was added and stirring was continued for 15 min. Some MgSO4 was added and stirring was continued for 15 min. The mixture was filtered, washed with CH2Cl2 and concentrated. The crude product was purified by silica gel chromatography using a cyclohexane/EtOAc gradient, providing the title compound (302 mg, 16%) as orange oil.

Workup

  1. temperatureThe mixture was heated to 100° C.
  2. stirringstirring
  3. waitwas continued overnight
  4. temperatureThe mixture was cooled to rt
  5. stirringstirring
  6. waitwas continued for 15 min
  7. stirringstirring
  8. waitwas continued for 15 min
  9. filtrationThe mixture was filtered
  10. washwashed with CH2Cl2
  11. concentrationconcentrated
  12. customThe crude product was purified by silica gel chromatography

Sources & evidence

ORD record
ord-558057d9004d4f4eaacc60b158bf1dd7
Source dataset
uspto-grants-2014_01
Patent number
US08623866B2

Reaction notes

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