THE CRYSTAL STRUCTURE OF PYRAZINE-2,3-DICARBOXYLIC ACID DIHYDRATE

Abstract

Abstract The crystal structure of pyrazine-2,3-dicarboxylic acid dihydrate has been determined by X-ray diffraction method. The lone pairs of N atoms in the pyrazine ring participate in H-bonds, while some lone pairs of O atoms are free from H-bonds. This fact suggests that the O–H···N bond is energetically more favored than the O–H···O bond in carboxylic acids with an aromatic six-membered ring.