Synthesis, crystal structure and Hirshfeld surface analysis of 1-[(1-octyl-1<i>H</i>-1,2,3-triazol-4-yl)methyl]-3-phenyl-1,2-dihydroquinoxalin-2(1<i>H</i>)-one

In the title mol-ecule, C₂₅H₂₉N₅O, the di-hydro-quinoxaline unit is not quite planar (r.m.s. deviation = 0.030 Å) as there is a dihedral angle of 2.69 (3)° between the mean planes of the constituent rings and the mol-ecule adopts a hairpin conformation. In the crystal, the polar portions of the mol-ecules are associated through C-H⋯O and C-H⋯N hydrogen bonds and C-H⋯π(ring) and C=O⋯π(ring) inter-actions, forming thick layers parallel to the <i>bc</i> plane and with the <i>n</i>-octyl groups on the outside surfaces.