Crystal structure of (E)-4-hydroxy-6-methyl-3-{1-[2-(4-nitrophenyl)hydrazinylidene]ethyl}-2H-pyran-2-one

Abstract

The title compound, C14H13N3O5 (HMNP), was synthesized by the simple condensation of p-nitrophenylhydrazine with dehydroacetic acid (DHA) in a 1:1 molar ratio in ethanol. HMNP has been characterized by using FT-IR, 1H and 13C NMR and UV-Vis spectroscopic and single-crystal X-ray diffraction techniques. The crystal packing reveals strong hydrogen bonds between the NH group and the carbonyl O atom of dihydropyranone moiety, forming chains along [101]. The thermal stability of the synthesized compound was confirmed by thermogravimetric analysis and it was found to be stable up to 513K. The UV-Vis spectrum shows the presence of a strong band at λmax 394nm. 1H NMR and single-crystal X-ray analyses confirmed the presence of the enol form of the ligand and dominance over the keto form. The crystal studied was a non-merohedral twin with the refined ratio of the twin components being 0.3720(19):0.6280(19).