2,3-Di­ethyl­benzo[g]quinoxaline

The title compound, C(16)H(16)N(2), was synthesized by dispersing 3,4-hexa­nedione in a methanol–water solution containing the acid catalyst NH(4)HF(2), then adding 1,2-di­aminona­phthalene. The fused-ring system of the title compound is close to planar (r.m.s. deviation = 0.028 Å); one of the pendant methyl C atoms lies close to the ring plane [deviation = 0.071 (2) Å; N—C—C—C = −0.27 (18)°] whereas the other is significantly displaced [–1.7136 (18) Å; 91.64 (16)°]. The mol­ecules pack in space group I [Image: see text] in a distinctive criss-cross motif supported by numerous aromatic π–π stacking inter­actions [shortest centroid–centroid separation = 3.5805 (6) Å]. [Image: see text]