Title of article :
Crystal structure, Hirshfeld surface analysis and DFT study of 1-ethyl-3-phenyl-1,2-dihydroquinoxalin-2-one
Author/Authors :
Al Ati, Gamal Laboratory of Heterocyclic Organic Chemistry URAC 21 - Pharmacochemistry Competence Center, Morocco , Chkirate, Karim Laboratory of Heterocyclic Organic Chemistry URAC 21 - Pharmacochemistry Competence Center, Morocco , Mashrai, Ashraf Department of Pharmacy - University of Science and Technology, Ibb Branch, Ibb, Yemen , Mague , Joel T. Department of Chemistry - Tulane University, USA , Achour, Redouane Laboratory of Heterocyclic Organic Chemistry URAC 21 - Pharmacochemistry Competence Center, Morocco , Essassi, El Mokhtar Laboratory of Heterocyclic Organic Chemistry URAC 21 - Pharmacochemistry Competence Center, Morocco
Abstract :
In the title molecule, C16H14N2O, the dihydroquinoxaline moiety is not planar as there is a dihedral angle of 4.51 (5)° between the constituent rings. In the crystal, C—H⋯O hydrogen bonds form helical chains about the crystallographic 21 screw axis in the b-axis direction. Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (51.7%), H⋯C/C⋯H (26%) and H⋯O/O⋯H (8.5%) interactions. The optimized structure calculated using density functional theory (DFT) at the B3LYP/6–311 G(d,p) level is compared with the experimentally determined structure in the solid state. The calculated HOMO–LUMO energy gap is 3.8918 eV.