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

HRID 2244776Notes

Reaction equation

HRID 2244776 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 86%

Conditions

Temperature
180 °C

Procedure

A mixture of 2.08 g of 3-trifluoromethyl-1H-pyrazole-4-carboxylic acid ethyl ester (10 mmol) and 2.3 ml of trimethyl phosphate (20 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. 1.9 g (86% 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-d51abd7ebe224db0ae023ae5d56d321e
Source dataset
uspto-grants-2010_03
Patent number
US07678924B2

Reaction notes

Loading…