Investigations on pyrazine derivatives

Abstract A simple method is given for the preparation of pyrazine tetracarboxylic acid from o‐diaminobenzene. A stable 1,4‐dihydro‐compound only is produced on hydrogenating tetraethyl pyrazine tetracarboxylate at relatively high pressures and temperatures. The cause of this stability must be sought in the presence of two, probably mutually independent, mesomeric systems.