Reaktion #51141

Reaktionsgleichung

hydrochloric acid

5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)pyrazole-3-carbonitrile

methyl pyrazinecarboxylate

CH3ONa CH3OH

→

N-[3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)pyrazole-5-yl]pyrazine-2-carboxamide

Ausbeute 77.0%

Lösungsmittel

water

acetonitrile

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeat room temperature
2. 2
   Sonstigewere precipitated
3. 3
   workup.ADDITIONThereto was added 10 ml of ethyl acetate
4. 4
   Extraktionfollowed by extraction
5. 5
   WaschenThe organic layer was washed with saturated saline
6. 6
   Trocknendried over anhydrous sodium sulfate
7. 7
   SonstigeAfter removal of the sodium sulfate
8. 8
   Filtrationby filtration
9. 9
   Einengenthe layer was concentrated
10. 10
    Filtrationthe resulting crystals were filtrated
11. 11
    WaschenThe crystals were washed with a small amount of hexane and ethyl acetate
12. 12
    Sonstigethe dried

Vorschrift

Into a mixture of 0.5 g (1.6 mmol) of 5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)pyrazole-3-carbonitrile, 0.24 g (1.7 mmol) of methyl pyrazinecarboxylate, and 0.5 ml of acetonitrile was gradually added 0.3 g (1.6 mmol) of 28% CH3ONa/CH3OH at room temperature. After 2 hours of stirring at room temperature, 5 ml of water and then concentrated hydrochloric acid were added thereto to make the mixture pH 2, whereby crystals were precipitated. Thereto was added 10 ml of ethyl acetate, followed by extraction. The organic layer was washed with saturated saline and then dried over anhydrous sodium sulfate. After removal of the sodium sulfate by filtration, the layer was concentrated and the resulting crystals were filtrated. The crystals were washed with a small amount of hexane and ethyl acetate and the dried to obtain 0.5 g (yield 77%) of N-[3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)pyrazole-5-yl]pyrazine-2-carboxamide.

Quelle