Crystal structure, Hirshfeld surface analysis and inter­action energy and DFT studies of 2-chloro­ethyl 2-oxo-1-(prop-2-yn-1-yl)-1,2-di­hydro­quinoline-4-carboxyl­ate

The title compound, C(15)H(12)ClNO(3), consists of a 1,2-di­hydro­quinoline-4-carb­oxyl­ate unit with 2-chloro­ethyl and propynyl substituents, where the quinoline moiety is almost planar and the propynyl substituent is nearly perpendicular to its mean plane. In the crystal, the mol­ecules form zigzag stacks along the a-axis direction through slightly offset π-stacking inter­actions between inversion-related quinoline moieties which are tied together by inter­molecular C—H(Prpn­yl)⋯O(Carbx) and C—H(Chlethy)⋯O(Carbx) (Prpnyl = propynyl, Carbx = carboxyl­ate and Chlethy = chloro­eth­yl) hydrogen bonds. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (29.9%), H⋯O/O⋯H (21.4%), H⋯C/C⋯ H (19.4%), H⋯Cl/Cl⋯H (16.3%) and C⋯C (8.6%) inter­actions. Hydrogen bonding and van der Waals inter­actions are the dominant inter­actions in the crystal packing. Computational chemistry indicates that in the crystal, the C—H(Prpn­yl)⋯O(Carbx) and C—H(Chlethy)⋯O(Carbx) hydrogen bond energies are 67.1 and 61.7 kJ mol(−1), respectively. Density functional theory (DFT) optimized structures at the B3LYP/ 6–311 G(d,p) level are compared with the experimentally determined mol­ecular structure in the solid state. The HOMO–LUMO behaviour was elucidated to determine the energy gap.