Ethyl 2-(4-benzyl-3-methyl-6-oxo-1,6-dihydrorwridazin-1-yl)acetate: crystal structure and Hirshfeld surface analysis

The title compound, C16H18N2O3, is constructed about a central oxopyridazinyl ring (r.m.s. deviation = 0.0047 angstrom), which is connected to an ethylacetate group at the N atom closest to the carbonyl group, and benzyl and methyl groups second furthest and furthest from the carbonyl group, respectively. An approximately orthogonal relationship exists between the oxopyridazinyl ring and the best plane through the ethylacetate group [dihedral angle = 77.48 (3)degrees]; the latter lies to one side of the central plane [the N-r-N-r-C-m-C-c (r = ring, m = methylene, c = carbonyl) torsion angle being 104.34 (9)degrees]. In the crystal, both H atoms of the N-bound methylene group form methylene-C-H center dot center dot center dot O(ring carbonyl) or N(pyridazinyl) interactions, resulting in the formation of a supramolecular tape along the a-axis direction. The tapes are assembled into a three-dimensional architecture by methyl- and phenyl-C-H center dot center dot center dot O(ring carbonyl) and phenyl-C-H center dot center dot center dot O(ester carbonyl) interactions. The analysis of the calculated Hirshfeld surface indicates the dominance of H center dot center dot center dot H contacts to the overall surface (i.e. 52.2%). Reflecting other identified points of contact between molecules noted above, O center dot center dot center dot H/H center dot center dot center dot O (23.3%), C center dot center dot center dot H/H center dot center dot center dot C (14.7%) and N center dot center dot center dot H/H center dot center dot center dot N (6.6%) contacts also make significant contributions to the surface.