Crystal structure, Hirshfeld surface analysis and corrosion inhibition study of 3,6-bis-(pyridin-2-yl)-4-{[(3aS,5S,5aR,8aR,8bS)-2,2,7,7-tetra-methyl-tetra-hydro-5H-bis-[1,3]dioxolo[4,5-b:4',5'-d]pyran-5-yl)meth-oxy]meth-yl}pyridazine monohydrate

Crystal structure, Hirshfeld surface analysis and inter-action energy and DFT studies of methyl 4-[3,6-bis-(pyridin-2-yl)pyridazin-4-yl]benzoate

The title com-pound, C22H16N4O2, contains two pyridine rings and one meth-oxy-carbonyl-phenyl group attached to a pyridazine ring which deviates very slightly from planarity. In the crystal, ribbons consisting of inversion-related chains of mol-ecules extending along the a-axis direction are formed by C-HMthy⋯OCarbx (Mthy = methyl and Carbx = carboxyl-ate) hydrogen bonds. The ribbons are connected into layers parallel to the bc plane by C-HBnz⋯π(ring) (Bnz = benzene) inter-actions. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (39.7%), H⋯C/C⋯H (27.5%), H⋯N/N⋯H (15.5%) and O⋯H/H⋯O (11.1%) inter-actions. Hydrogen-bonding and van der Waals inter-actions are the dominant inter-actions in the crystal packing. Computational chemistry indicates that in the crystal, C-HMthy⋯OCarbx hydrogen-bond energies are 62.0 and 34.3 kJ mol-1, respectively. Density functional theory (DFT) optimized structures at the B3LYP/6-311G(d,p) level are com-pared with the experimentally determined mol-ecular structure in the solid state. The HOMO-LUMO behaviour was elucidated to determine the energy gap.

Crystal structure, Hirshfeld surface analysis and inter-action energy and DFT studies of 4-[(prop-2-en-1-yl-oxy)meth-yl]-3,6-bis-(pyridin-2-yl)pyridazine

The title compound, C18H16N4O, consists of a 3,6-bis-(pyridin-2-yl)pyridazine moiety linked to a 4-[(prop-2-en-1-yl-oxy)meth-yl] group. The pyridine-2-yl rings are oriented at a dihedral angle of 17.34 (4)° and are rotated slightly out of the plane of the pyridazine ring. In the crystal, C-HPyrd⋯NPyrdz (Pyrd = pyridine and Pyrdz = pyridazine) hydrogen bonds and C-HPrp-oxy⋯π (Prp-oxy = prop-2-en-1-yl-oxy) inter-actions link the mol-ecules, forming deeply corrugated layers approximately parallel to the bc plane and stacked along the a-axis direction. Hirshfeld surface analysis indicates that the most important contributions for the crystal packing are from H⋯H (48.5%), H⋯C/C⋯H (26.0%) and H⋯N/N⋯H (17.1%) contacts, hydrogen bonding and van der Waals inter-actions being the dominant inter-actions in the crystal packing. Computational chemistry indicates that in the crystal, the C-HPyrd⋯NPyrdz hydrogen-bond energy is 64.3 kJ mol-1. Density functional theory (DFT) optimized structures at the B3LYP/6-311 G(d,p) level are compared with the experimentally determined mol-ecular structure in the solid state. The HOMO-LUMO behaviour was elucidated to determine the energy gap.