Reaktion #215562

Reaktionsgleichung

2,3-Dicyano-5-hydroxy-6-(m-chlorophenyl)pyrazine

phosphorus oxychloride

triethylamine

→

2,3-dicyano-5-chloro-6-(m-chlorophenyl)pyrazine

Ausbeute 84.0%

Lösungsmittel

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe mixture was cooled to 0° to 5° C.
2. 2
   workup.ADDITIONwas added dropwise over the period of 30 minutes
3. 3
   workup.ADDITIONAfter the addition
4. 4
   Temperaturthe mixture was refluxed for 3 hours
5. 5
   Filtrationthe precipitate was collected by filtration
6. 6
   SonstigeRecrystallization from carbon tetrachloride

Vorschrift

2,3-Dicyano-5-hydroxy-6-(m-chlorophenyl)pyrazine (25.67 g; 0.10 mole) was put into 46.2 g (0.30 mole) of phosphorus oxychloride. The mixture was cooled to 0° to 5° C., and with stirring 10.1 g (0.1 mole) of triethylamine was added dropwise over the period of 30 minutes. After the addition, the mixture was refluxed for 3 hours. The reaction mixture was worked up in the same way as in Example 3. Petroleum ether (50 ml) was added to the resulting oily product, and the precipitate was collected by filtration. Recrystallization from carbon tetrachloride afforded 23.1 g (yield 83%) of 2,3-dicyano-5-chloro-6-(m-chlorophenyl)pyrazine.

Quelle