1- Methylpyrazinium iodide 4-oxide

Mel, AcMe, or EtOH , sealed, 100°C, 4 h 95%) 286 homologues were made likewise 286 and similar treatment of pyrazine 1,4-dioxide gave a separable ( ) mixture of 1-methylpyrazinium iodide and its 4-oxide in approximately equal amounts.286... 

Quaternization of the four dimethylpyrazine A(-oxides and 2,3-diphenylpyrazine 1-oxide with methyl iodide in a sealed tube at 80 gave the 4-methylpyrazinium 1-oxide iodides, but 3-phenyl-, 2,5-diphenyl- and 3,5-diphenylpyrazine 1 -oxides and dimethylpyrazine 1,4-dioxides could not be quaternized. The quaternary salts were reduced by sodium borohydride to A -hydroxypiperazines (766). 

Methylation (666, 912) of 2-methoxypyrazine with methyl iodide in dimethyl sulfoxide at room temperature gave 3-methoxy-l-methylpyrazinium iodide with a rate of methylation relative to pyrazine of 1.05 (666). 2-Methoxypyrazine with tetracyanoethylene oxide gave a small yield of 3 ethoxypyrazinium dicyano-methylide (53) (1094). Alkylation of 2-methoxypyrazine with ethyl methyl ketone in the presence of sodium in liquid ammonia to give 2-s-butyl-6-methoxypyrazine (17%) has been described (614). The reactions of 3-hydroxy-2,5-dimethylpyrazine and alkylhalides have been examined (1095). 

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See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

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