Crystal structures and Hirshfeld surface analyses of 4-benzyl-6-phenyl-4,5-dinvdropyriaazin-3(2H)-one and methyl 2-[5-(2,6-dichlorobenzyl)-6-oxo-3-phenyl-1,4,5,6-tetrahydropyridazin-1-yl]acetate

Abstract

The asymmetric units of the title compounds both contain one nonplanar molecule. In 4-benzyl-6-phenyl-4,5-dihydropyridazin-3(2H)-one, C17H14N2O, (I), the phenyl and pyridazine rings are twisted with respect to each other, making a dihedral angle of 46.69 (9)degrees; the phenyl ring of the benzyl group is nearly perpendicular to the plane of the pyridazine ring, the dihedral angle being 78.31 (10)degrees. In methyl 2-[5-(2,6-dichlorobenzyl)-6-oxo-3-phenyl-1,4,5,6-tetrahydropyridazin-1-yl]acetate, C20H16C12N2O3, (II), the phenyl and pyridazine rings are twisted with respect to each other, making a dihedral angle of 21.76 (18)degrees, whereas the phenyl ring of the dichlorobenzyl group is inclined to the pyridazine ring by 79.61 (19)degrees. In the crystal structure of (I), pairs of N-H center dot center dot center dot O hydrogen bonds link the molecules into inversion dimers with an R-2(2)(8) ring motif. In the crystal structure of (II), C-H center dot center dot center dot O hydrogen bonds generate dimers with R-1(2)(7), R(2)(2)6) and R-2(2)(18) ring motifs. The Hirshfeld surface analyses of compound (I) suggests that the most significant contributions to the crystal packing are by H center dot center dot center dot H (48.2%), C center dot center dot center dot H/H center dot center dot center dot C (29.9%) and O center dot center dot center dot H/H center dot center dot center dot O (8.9%) contacts. For compound (II), H center dot center dot center dot H (34.4%), C center dot center dot center dot H/H center dot center dot center dot C (21.3%) and O center dot center dot center dot H/H center dot center dot center dot O (16.5%) interactions are the most important contributions.