Pyrazinethiones oxidation

The formation of such pyrazines by primary synthesis has been covered in Chapters 1 and 2 the meagre literature on their formation by oxidation of pyrazinethiones or pyrazinethiols is mentioned in Section 6.1.2. 

Methyl-5,6-diphenylpyrazine 4-oxide l-Methyl-5,6-diphenyl-2(l//)-pyrazinethione... 

Pyrazinethiones (123) with alkyl halides in the presence of base produce pyrazinylthio compounds (124), which are easily oxidized with peroxymaleic acid to the sulfoxides (125). Cyanomethyl sulfoxide (125 = CN) is alkylated on the methylene carbon between the sulfoxide and cyano... 

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