Trimethyl Phosphate → Ethyl 3-difluoromethyl-1-methyl-4-pyrazole carboxylate

HRID 2244774Notes

Reaction equation

HRID 2244774 reaction equation
[CH2:1]([O:3][C:4]([C:6]1[C:7]([CH:11]([F:13])[F:12])=[N:8][NH:9][CH:10]=1)=[O:5])[CH3:2].P(OC)(OC)(O[CH3:17])=O>>[CH2:1]([O:3][C:4]([C:6]1[C:7]([CH:11]([F:12])[F:13])=[N:8][N:9]([CH3:17])[CH:10]=1)=[O:5])[CH3:2]

Participants

3

Reactant 2

HCID 10541Trimethyl PhosphateHCID 178469922HCID 178469922, compound

Product 1

HCID 11644126Ethyl 3-difluoromethyl-1-methyl-4-pyrazole carboxylateYield 64%

Conditions

Temperature
180 °C

Procedure

A mixture of 5.7 g of 3-difluoromethyl-1H-pyrazole-4-carboxylic acid ethyl ester (30 mmol) and 25 ml of trimethyl phosphate (214 mmol) is stirred at a temperature of 180° C. for 18 hours. 250 ml of an ice-water mixture are then added. The resulting reaction product is filtered, washed with water and dissolved in 50 ml of ethyl acetate. The organic phase is washed with 50 ml of saturated sodium chloride solution and dried over sodium sulfate and concentrated by evaporation. 3.9 g (64% of theory) of 3-difluoromethyl-1-methyl-1H-pyrazole-4-carboxylic acid ethyl ester are obtained in the form of crystals (m.p. 59-60° C.).

Workup

  1. customThe resulting reaction product
  2. filtrationis filtered
  3. washwashed with water
  4. dissolutiondissolved in 50 ml of ethyl acetate
  5. washThe organic phase is washed with 50 ml of saturated sodium chloride solution
  6. dry with materialdried over sodium sulfate
  7. concentrationconcentrated by evaporation

Sources & evidence

ORD record
ord-459e59df174945eb9b61201539530d07
Source dataset
uspto-grants-2010_03
Patent number
US07678924B2

Reaction notes

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