Reaktion #88421

Reaktionsgleichung

Potassium trifluorovinylborate

methyl 4-(5-bromo-4-(difluoromethyl)thiazol-2-yl)-1-methyl-1H-pyrazole-5-carboxylate

potassium trifluoro(vinyl)borate

→

title compound

Ausbeute 58.0%

methyl 4-(4-(difluoromethyl)-5-vinylthiazol-2-yl)-1-methyl-1H-pyrazole-5-carboxylate

Ausbeute 58.0%

Lösungsmittel

ethyl acetate

ethanol

triethylamine

triethylamine

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeobtained in (Example 1.4) <Step 1>
2. 2
   workup.STIRRINGthe obtained mixture was stirred again in a nitrogen atmosphere at 100° C. for 2 hours 40 minutes
3. 3
   ExtraktionAn organic layer was extracted
4. 4
   Trocknenwas then dried over anhydrous sodium sulfate
5. 5
   workup.DISTILLATIONThe solvent was distilled away under reduced pressure
6. 6
   Sonstigethe obtained residue was then purified by silica gel column chromatography (silica gel:eluent; heptane:ethyl acetate=95:5-50:50)

Vorschrift

Potassium trifluorovinylborate (172 mg), 1,1′-bis(diphenylphosphino)ferrocene-palladium(II) dichloride (31 mg), and triethylamine (59.4 μl) were added to an ethanol (2.1 ml) solution of the methyl 4-(5-bromo-4-(difluoromethyl)thiazol-2-yl)-1-methyl-1H-pyrazole-5-carboxylate (150 mg) obtained in (Example 1.4) <Step 1>, and the obtained mixture was then stirred in a nitrogen atmosphere at 100° C. for 17 hours. Thereafter, potassium trifluoro(vinyl)borate (342 mg), 1,1′-bis(diphenylphosphino)ferrocene-palladium(II) dichloride (62 mg), and triethylamine (59.4 μl) were added to the reaction solution, and the obtained mixture was stirred again in a nitrogen atmosphere at 100° C. for 2 hours 40 minutes. Thereafter, ethyl acetate (100 ml) and a saturated saline (50 ml) were added to the reaction solution. An organic layer was extracted, and was then dried over anhydrous sodium sulfate. The solvent was distilled away under reduced pressure, and the obtained residue was then purified by silica gel column chromatography (silica gel:eluent; heptane:ethyl acetate=95:5-50:50), so as to obtain the title compound (74 mg) in the form of a colorless solid.

Quelle