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 C18H17Cl2N5O2 (3) is synthesized and characterized by IR, H-1 NMR, C-13 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-HaEuro broken vertical bar 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-HaEuro broken vertical bar O hydrogen bonds and pi aEuro broken vertical bar pi interactions are responsible for crystal stabilization.