Syntheses, spectral, thermal and structural characterization of 2-hydroxyanilinium and 2-amino-3-hydroxy-pyridinium squarates

Abstract

New salts of 2-hydroxyaniline and 2-amino-3-hydroxypyridine with squaric acid were synthesized and characterized by elemental analyses, IR spectroscopy and thermal analyses (TG, DTG and DTA). The crystal structures of bis(2-hydroxyanilinium) squarate, [(C6H8NO+)(2)(C4O4)(2-)] (1) and bis(2-amino-3-hydroxy-pyridinium) squarate dihydrate, [(C5H7N2O+)(2)(C4O4)(2-)]center dot 2 H2O (2) were determined by single crystal X-ray diffraction. Both compounds crystallize in the monoclinic system, space group P2(1)/c. The organic ammonium squarates decompose in two thermal steps.