| 摘要 |
PURPOSE: Provided is a preparation method in making 3-trifluoromethyl-5-hydroxylpyrazole phosphoric acid ester derivatives using water as a solvent in place of organic solvent. Using water facilitates the easy separation of side products such as 3-trifluoromethyl-5-hydroxylpyrazole and halophosphate in the esterification reaction between derivatives of 3-trifluoromethyl-5-hydroxylpyrazole and halophosphate with catalysts such as dimethylaminopyridine and strong inorganic bases like hydroxides of alkali metal. The reaction process shortens the reaction time and offers high yield because the pure product is obtained by a simple extraction method. CONSTITUTION: The preparation method of the compound represented by the formula 1 comprises: adding 0.01 mole of 1-methyl-3-trifluoromethyl-5-hydroxylpyrazole and 0.02 mole of sodium hydroxide in 50mL of water; adding 0.01 mole of diethylchlorothiophosphate and 0.8 mmole of 4-dimethylaminopyridine to the above mixture; stirring the reactants at room temperature for 48 hours; and extracting the reaction mixture with 30mL of dichloromethane two times, drying the mixture with MgSO4 and evaporating the solvent to obtain the over 95% pure product, O,OO,O-diethyl-OO-(1-methyl-3-trifluoromethyl- 5-pyrazoyl)thiophosphoric ester in 88% yield. In the formula 1, R1 is hydrogen or halogen atom; R2 is straight or branched low alkyl group of C1-C6; R3 is C1-C6 low alkoxy, C1-C6 straight or branched low alkylthio, phenoxy or thiophenoxy group; R4 is hydrogen atom, C1-C6 straight or branched low alkyl, or substituted or unsubstituted phenyl group where the substituents are halogen atom, trifluoromethyl, or C1-C6 straight or branched low alkoxy group; and X is oxygen or sulfur atom.
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