Potassium Hydroxide → methyl 3-amino-1-methyl-1H-pyrazole-5-carboxylate

HRID 2291364Notes

Reaction equation

HRID 2291364 reaction equation
[OH-].[K+].Cl.[NH2:4]O.[C:6]([C:10]1[N:14]([CH3:15])[N:13]=[C:12](C2C=C(C)NC=2C)[CH:11]=1)([O:8][CH3:9])=[O:7]>O.C(O)C>[C:6]([C:10]1[N:14]([CH3:15])[N:13]=[C:12]([NH2:4])[CH:11]=1)([O:8][CH3:9])=[O:7]

Participants

6

Procedure

A solution of potassium hydroxide (5.08 g, 90.7 mmol) in water (76 mL) and ethanol (76 mL) was added to a slurry of hydroxylamine hydrochloride (11.44 g, 169.5 mmol) in ethanol (127 mL). Then, 5-carbomethoxy-3-(2,5-dimethylpyrrolyl)-1-methylpyrazole (8.5 g, 36.6 mmol) was added and the mixture was refluxed under a nitrogen atmosphere for 65 h. The solvents were removed at reduced pressure and the residue was triturated with ether. Sodium sulfate was added and the heterogenous mixture was filtered. The filtrate was concentrated and the residue was chromatographed on Silica Woelm®TSC (300 g, ethyl acetate-hexane gradient) to give 4.61 g, 81% of 5-carbomethoxy-3-amino-1-methylpyrazole as a white solid mp 114° to 118° C.; 1H-NMR (CDCl3) σ 6.17 (s, 1H), 4.02 (s, 3H), 3.88 (s, 1H), 3.7 (br s, 2H); IR (KBr) 1719, 1551, 1263, 1102, 756 cm-1.

Workup

  1. temperaturethe mixture was refluxed under a nitrogen atmosphere for 65 h
  2. customThe solvents were removed at reduced pressure
  3. customthe residue was triturated with ether
  4. additionSodium sulfate was added
  5. filtrationthe heterogenous mixture was filtered
  6. concentrationThe filtrate was concentrated
  7. customthe residue was chromatographed on Silica Woelm®TSC (300 g, ethyl acetate-hexane gradient)

Sources & evidence

ORD record
ord-af90506af5f2495d8c5cfa54e689bbaf
Source dataset
uspto-grants-1989_01
Patent number
US04795817

Reaction notes

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