Reacción #44982

Ecuación de reacción

Pyrazine-2-carbonitrile

sulfuryl chloride

→

title compound

Rendimiento 47.4%

3-Chloropyrazine-2-carbonitrile

Rendimiento 47.4%

Disolventes

toluene

N,N-dimethylformamide

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturacooling
2. 2
   workup.ADDITIONAfter completion of addition
3. 3
   OtroThe toluene layer is separated
4. 4
   Extracciónthe residual red oil is extracted with diethyl ether
5. 5
   Temperaturacooled with ice
6. 6
   workup.ADDITIONafter pouring
7. 7
   workup.ADDITIONby adding saturated aqueous sodium hydrogen carbonate solution
8. 8
   OtroThe organic layer is separated
9. 9
   Extracciónaqueous layer is extracted with diethyl ether
10. 10
    Lavadowashed with water
11. 11
    Secadodried over sodium sulfate
12. 12
    Otroevaporated
13. 13
    Otroto remove the solvent under reduced pressure
14. 14
    OtroThe resulting residue is purified by silica gel column chromatography (eluent: n-hexane/ethyl acetate=4/1)

Procedimiento

Pyrazine-2-carbonitrile (26.36 g) is dissolved in toluene (187 ml)/N,N-dimethylformamide (19 ml), and thereto is added dropwise sulfuryl chloride (135 g) under ice-cooling. After completion of addition, the reaction solution is warmed to room temperature gradually and stirred overnight. The toluene layer is separated and the residual red oil is extracted with diethyl ether. The organic layers are combined, cooled with ice, and after pouring thereto ice-water, neutralized by adding saturated aqueous sodium hydrogen carbonate solution. The organic layer is separated, and aqueous layer is extracted with diethyl ether. The organic layers are combined, washed with water, dried over sodium sulfate and evaporated to remove the solvent under reduced pressure. The resulting residue is purified by silica gel column chromatography (eluent: n-hexane/ethyl acetate=4/1) to give the title compound (16.58 g).

Fuente