Trimethyl Phosphate → 1H-Pyrazole-4-carboxylic acid, 1-methyl-3-(trifluoromethyl)-, ethyl ester

HRID 2244775Notes

Reaction equation

HRID 2244775 reaction equation
[CH2:1]([O:3][C:4]([C:6]1[C:7]([C:11]([F:14])([F:13])[F:12])=[N:8][NH:9][CH:10]=1)=[O:5])[CH3:2].P(OC)(OC)(O[CH3:18])=O>>[CH2:1]([O:3][C:4]([C:6]1[C:7]([C:11]([F:13])([F:14])[F:12])=[N:8][N:9]([CH3:18])[CH:10]=1)=[O:5])[CH3:2]

Participants

3

Reactant 2

HCID 10541Trimethyl PhosphateHCID 178469923HCID 178469923, compound

Product 1

HCID 27829701H-Pyrazole-4-carboxylic acid, 1-methyl-3-(trifluoromethyl)-, ethyl esterYield 90%

Conditions

Temperature
180 °C

Procedure

A mixture of 4.16 g of 3-trifluoromethyl-1H-pyrazole-4-carboxylic acid ethyl ester (20 mmol) and 10 ml of trimethyl phosphate (86.4 mmol) is stirred at a temperature of 180° C. for 16 hours. 200 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 twice with 50 ml of saturated sodium chloride solution each time and dried over sodium sulfate and concentrated by evaporation. 4.0 g (90% of theory) of 3-trifluoromethyl-1-methyl-1H-pyrazole-4-carboxylic acid ethyl ester are obtained in the form of crystals (m.p. 55-57° 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 twice with 50 ml of saturated sodium chloride solution each time
  6. dry with materialdried over sodium sulfate
  7. concentrationconcentrated by evaporation

Sources & evidence

ORD record
ord-dd4202ca500b483e8d9bd10daffa7981
Source dataset
uspto-grants-2010_03
Patent number
US07678924B2

Reaction notes

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