Pyrazinecarboxamides hydrolysis

Chloro-2-pyrazinecarboxamide 4-oxide (11) gave 6-chloro-2-pyrazinecar-boxylic acid 4-oxide (12) (NaNOz, 50% H2S04, 20°C, 1 h, then 60°C, 1 h 75% presumably this indirect method was adopted to avoid hydrolysis of the chloro substituent).669... 

Two important reactions in this category have been covered already Hofmann degradation to pyrazinamines (Section 7.3.1) and hydrolysis to pyrazinecarboxylic acids (Section 8.1.1). The remaining reactions of pyrazinecarboxamides and related derivatives are illustrated in the following examples ... 

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