Thionyl Chloride → 3,5-Dichloro-6-ethylpyrazine-2-carbonitrile
Reaction equation
[Cl:1][C:2]1[C:3]([C:11]([NH2:13])=O)=[N:4][C:5]([CH2:9][CH3:10])=[C:6]([Cl:8])[N:7]=1.S(Cl)(Cl)=O>CN(C=O)C>[Cl:1][C:2]1[C:3]([C:11]#[N:13])=[N:4][C:5]([CH2:9][CH3:10])=[C:6]([Cl:8])[N:7]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
To a mixture of 3,5-dichloro-6-ethylpyrazine-2-carboxamide (1.0 g) and DMF (15 mL), thionyl chloride (1 mL) was added at room temperature and stirred for 20 minutes. The reaction liquid was poured into ice-cold water and extracted with ethyl acetate. The organic layer was washed with saturated aqueous sodium chloride and then dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (eluent; ethyl acetate:n-hexane) to give 3,5-dichloro-6-ethylpyrazine-2-carbonitrile (608 mg) as a slightly yellow oil.