Crystal structure and Hirshfeld surface analysis of (1 H -imidazole-κ N 3 )[4-methyl-2-({[2-oxido-5-(2-phenyl-diazen-1-yl)phen-yl]methyl-idene}amino)penta-noate-κ 3 O , N , O ']copper(II).

The title copper(II) complex, [Cu(C 18 H 19 N 3 O 3 )(C 3 H 4 N 2 )], consists of a tridentate ligand synthesized from l-leucine and azo-benzene-salicyl-aldehyde. One imidazole mol-ecule is additionally coordinated to the copper(II) ion in the equatorial plane. The crystal structure features N-H⋯O hydrogen bonds. A Hirshfeld surface analysis indicates that the most important contributions to the packing are from H⋯H (52.0%) and C⋯H/H⋯C (17.9%) contacts.