2-Hydroxymethyl-5-methylpyrazine oxidation

Dimethylpyrazine gave successively its 1-oxide (258) (H202), 2-acetoxymethyl-5-methylpyrazine (259, R = Ac), 2-hydroxymethyl-5-methylpyrazine (259, R = H) (HO ), and 5-methyl-2-pyrazinecarboxyhc acid (260) (KMn04 for details of all stages in this indirect route, see original paper).432... 

Dimethylpyrazine 1-oxide (280) gave 2-acetoxymethyl-3-methylpyrazine (281) (neat Ac20, reflux, 30 min 77%) 1272 the isomeric 2,6-dimethyl-pyrazine 1-oxide gave a separable mixture of 2-acetoxymethyl-6-methylpyrazine (282, R = Ac) and 2-hydroxymethyl-6-methylpyrazine (282, R = H), the latter arising presumably by hydrolysis during the work up (neat Ac20, reflux, 1 h 40 and 12%, respectively).1307... 

Peroxyacetic acid oxidation of 2-acetoxymethyl-5-methylpyrazine gave the 1,4-dioxide which hydrolyzed in 0.1% sulfuric acid to 2-hydroxymethyl-5-methyl-pyrazine 1,4-dioxide (625) and 2,3-di(acetoxymethyl)pyrazine 1,4-dioxide was subjected to transesterification with lower alcohols in the presence of a catalytic amount of alkali to give 2,3-di(hydroxymethyl)pyrazine 1,4-dioxide (739). 

Dimethylamino-23-dimethylpyrazine 1-oxide in boiling acetic anhydride gave 2-acetoxymethyl-3-dimethylamino-5-methylpyrazine (793) which was not isolated but saponified directly to 3-dimethylamino-2-hydroxymethyl-5-methylpyrazine (793). 2-Amino-3-cyano-5-methylpyrazine 1,4-dioxide refluxed with (a) acetic anhydride gave 3-acetamido-2-cyano-5-hydroxy-6-methylpyrazine 1-oxide (532) and (6) sodium methoxide gave 3-amino-2-cyano-5-methoxy-6-methylpyrazine 1-oxide (532). 

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