Synthesis, crystal structure and Hirshfeld surface analysis of 1-[(1-octyl-1 H -1,2,3-triazol-4-yl)methyl]-3-phenyl-1,2-di-hydro-quinoxalin-2(1 H )-one.

In the title mol-ecule, C 25 H 29 N 5 O, 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 bc plane and with the n -octyl groups on the outside surfaces.