Crystal structure and Hirshfeld surface analysis of (aqua-κO)(methanol-κO)[N-(2-oxidobenzylidene)threoninato-κ³ O,N,O′]copper(II)

Abstract

In the title complex molecule, [Cu(C11H11NO4)(CH4O)(H2O)], the Cu atom is coordinated in a distorted square-pyramidal geometry by a tridentate ligand synthesized from L-threonine and salicylaldehyde, one methanol molecule and one water molecule. In the crystal, the molecules show intra- and intermolecular O—H...O hydrogen bonds. The Hirshfeld surface analysis indicates that the most important contributions to the packing are H...H (49.4%) and H...O/O...H (31.3%) contacts.

Crystal structure and Hirshfeld surface analysis of mono/bis(aqua-κO)[N-(2-oxidobenzylidene)valinato-κ3 O,N,O′]copper(II): dimeric Schiff base copper(II) complexes having different numbers of coordinated water molecules

“…In contrast, in molecule 2 the Cu2 atom exhibits a squarepyramidal geometry, being coordinated by the same tridentate ligand in the equatorial plane and by two water molecules in the equatorial and axial positions. The C19 N2 double-bond distance is 1.278 (3) A ˚, which is again close to the typical C N double-bond length for imines (Katsuumi et al, 2020). The Cu2-O5, Cu2-O6, and Cu2-O7 bond lengths are 1.9432 ( 14), 1.9411 (15), and 1.9956 (14) A ˚, respectively, which are close to a typical Cu-O bond length (Katsuumi et al, 2020).…”

“…In molecule 1, Cu1 has squareplanar geometry, being coordinated by a tridentate ligand synthesized from l-valine and salicylaldehyde in the equatorial plane and by one water molecule. The C7 N1 doublebond distance is 1.284 (3) A ˚, which is close to the typical C N double bond length for imines (Katsuumi, et al, 2020). The Cu1-O1, Cu1-O2 and Cu1-O3 bond lengths are 1.8995 (15), 1.9339 ( 16), and 1.9629 (15) A ˚, respectively, close to a typical Cu-O coordination bond length (Katsuumi et al, 2020).…”

“…In this study, we report the structure of the title Schiff base Cu II complex (Fig. 1) derived from l-valine and salicylaldehyde, which has a similar structure to that of one we reported previously (Katsuumi et al, 2020).…”

“…The Cu1-O1, Cu1-O2 and Cu1-O3 bond lengths are 1.8995 (15), 1.9339 ( 16), and 1.9629 (15) A ˚, respectively, close to a typical Cu-O coordination bond length (Katsuumi et al, 2020). The Cu1-N1 bond length of 1.9205 (16) A ˚corresponds to typical Cu-N bond length (Katsuumi et al, 2020). The lengths of these four coordination bonds in molecule 1 are almost the same.…”

“…Amino acid Schiff bases, which can easily be synthesized by mixing primary amines and carbonyl components, are organic ligands having an azomethine (C N) group. They play an important and diverse role in coordination chemistry (Qiu et al, 2008;Li et al, 2010;Xue et al, 2009;Katsuumi et al, 2020). We recently published a review (Akitsu et al, 2022) of the synthesis of amino acid Schiff base-metal complexes.…”