Reaction #696718

Reaction equation

4-iodo-3-methylthiobenzotrifluoride

3-cyclopropyl-5-hydroxy-1-methylpyrazole

triethylamine

potassium carbonate

→

3-cyclopropyl-1-methyl-4-(2-methylthio-4-trifluoromethylbenzoyl)-5-hydroxypyrazole

Yield 89.3%

Solvents

dioxane

Conditions

Workup

1. 1
   Othersealed
2. 2
   Otherthe interior of the autoclave was flushed with carbon monoxide (pressure: 65 kg/cm2)
3. 3
   Otherfollowed by a reaction at 140° C. for 8 hours
4. 4
   OtherAfter completion of the reaction
5. 5
   workup.DISTILLATIONthe solvent was distilled off
6. 6
   workup.DISSOLUTIONthe residue was dissolved in water
7. 7
   Filtrationinsoluble matters were filtered off
8. 8
   WashThe filtrate was washed with dichloromethane
9. 9
   Extractionextracted with dichloromethane
10. 10
    ExtractionThe obtained extract solution
11. 11
    Dryingwas dried over anhydrous sodium sulfate
12. 12
    workup.DISTILLATIONthe solvent was distilled off

Procedure

Into a 200 ml autoclave, 1.59 g of 4-iodo-3-methylthiobenzotrifluoride prepared in accordance with the following Preparation Example 10, 1.38 g of 3-cyclopropyl-5-hydroxy-1-methylpyrazole (after-mentioned Intermediate No. 1a-1), 0.5 g of triethylamine, 3.1 g of potassium carbonate, 0.22 g of palladium (II) bis-triphenylphosphine) dichloride and 40 ml of dioxane were put and sealed, and the interior of the autoclave was flushed with carbon monoxide (pressure: 65 kg/cm2), followed by a reaction at 140° C. for 8 hours. After completion of the reaction, the solvent was distilled off, and the residue was dissolved in water, and then insoluble matters were filtered off. The filtrate was washed with dichloromethane. The washed product was acidified (pH=1) with concentrated hydrochloric acid and extracted with dichloromethane. The obtained extract solution was dried over anhydrous sodium sulfate, and the solvent was distilled off to obtain 1.59 g of 3-cyclopropyl-1-methyl-4-(2-methylthio-4-trifluoromethylbenzoyl)-5-hydroxypyrazole (after-mentioned Compound No. a-82) as a reddish brown solid.

Source