Crystal structure, Hirshfeld surface analysis and density functional theory study of 1-nonyl-3-phenylquinoxaim-2-one

In the title molecule, C23H28N2O, the phenyl ring is inclined to the quinoxaline ring system at a dihedral angle of 20.40 (9)degrees. In the crystal, C-H center dot center dot center dot O interactions between neighbouring molecules form chains along the a-axis direction. Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H center dot center dot center dot H (70.6%), H center dot center dot center dot C/C center dot center dot center dot H (15.5%) and H center dot center dot center dot O/O center dot center dot center dot H (4.6%) interactions. The optimized structure calculated using density functional theory at the B3LYP/6-311 G(d,p) level is compared with the experimentally determined structure in the solid state. The calculated highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy gap is 3.8904 eV. Part of the n-nonyl chain attached to one of the nitrogen atoms of the quinoxaline ring system shows disorder and was refined with a double conformation with occupancies of 0.604 (11) and 0.396 (11).