5-(3,4-dichlorophenyl)-3-{[4-(2-pyridyl)piperazine-1-yl]methyl}-1,3,4-oxadiazole-2(3H)-one: Synthesis, characterization, X-ray and DFT structures

5-(3,4-Dichlorophenyl)-3-{[4-(2-pyridyl)piperazine-1-yl)]methyl}-1,3,4-oxadiazole-2(3H)-one C 18 H 17 Cl 2 N 5 O 2 ( 3 ) is synthesized and characterized by IR, 1 H NMR, 13 C NMR, elemental analyses, single-crystal X-ray diffraction, and the molecular structure is also optimized at the B3LYP/6-31G( d,p ) level using density functional theory (DFT). All data obtained from the spectral studies support the structural properties of 3 . The molecules are linked principally by C-H…O hydrogen bonds involving carbonyl atoms and carboxylate O atoms, forming R 2 2 (16) and R 4 2 (20) rings that link to give a one-dimensional network of molecules. An extensive two-dimensional network of C-H…O hydrogen bonds and π…π interactions are responsible for crystal stabilization.