Molecular Cocrystals of Carboxylic Acids. XIV. The Crystal Structures of the Adducts of Pyrazine-2,3-dicarboxylic Acid With 4-Aminobenzoic Acid, 3-Hydroxypyridine and 3-Amino-1,2,4-triazole

Abstract
The 1:1 molecular adducts of pyrazine-2,3-dicarboxylic acid with 4-aminobenzoic acid, [(C6H3N2O4)-(C7H8NO2)+], 3-hydroxypyridine, [(C6H4N2O4) (C5H5NO)], and 3-amino-1,2,4-triazole, [(C6H3N2O4)-(C2H5N4)+] have been prepared, and their structures determined by X-ray diffraction methods. All structures involve intra- and inter-molecular hydrogen-bonding interactions. The 1:2 complex of pyrazine-2,3-dicarboxylic acid with triphenylphosphine oxide has also been prepared, and characterized by using spectroscopic methods.