ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

The crystal structure of tetrameric copper(II) complexes, Hirshfeld surface analysis, and vector analyses of Cu₄OCl₆L₄ complexes with N-donor ligands

Gregor Ondrejovič, Ján Moncol, and Marian Koman

Faculty of Chemical and Food Technology, Institute of Inorganic Chemistry, Technology and Materials, Slovak University of Technology, Bratislava, Slovakia

E-mail: jan.moncol@stuba.sk

Received: 14 February 2020  Accepted: 18 June 2020

Abstract:

It is known, that in the Cu₄OX₆L₄ (X = Cl, Br) complexes can be present many different ligands L, including bioligands. The synthesis and characterization of Cu₄OBCl₆(ron)₄ (1) and Cu₄OCl₆(3-Mepy)₄ (2) (where ron is ronicol or 3-methanolpyridine and 3-Mepy is 3-methylpyridine) are reported. The complexes under study were X-ray structure analysis and Hirshfeld surface analysis. Tetranuclear Cu₄OX₆L₄ complexes with molecular structure (Fig. 1) can help to better understand the role of donor–acceptor and electron-transfer properties in copper proteins. The coordination sphere about each copper(II) atom is trigonal bipyramidal with three chlorine atoms in the equatorial plane. The apical positions are occupied by the central oxygen atom and the nitrogen atom of the respective ligand (CuCl₃ON). Here are studied chloridocomplexes of some N-donor ligands, L = chloro-promazine, ronicol (3-pyridylmethanol), 2-ethylpyrazine, seven derivatives of pyrazol and for comparisons 3-methylpyridine. The Cu₄OCl₆L₄ molecule is regarded as a supramolecular model of interactions between bioligand L and hypothetical “round-shaped” coordination tetra-receptor Cu₄OCl₆. Vector calculations applied usualy to mechanical and electrical macroconstructions are here applied to microconstructions represented by structures of Cu₄OX₆L₄ molecules. For vector calculations each Cu₄OX₆L₄ structure is placed (Fig. 1) into the three-dimensional Cartesian coordinate system with the central oxygen atom O1 placed in its origin 0. Studied bioligands are compared and described by molecular structural dynamics and corresponding shifts of electron densities by means of bond lenghts (O1–Cu, Cu–L, Cu–X) and structural distances (O1···X, O1···L).

Structure of the Cu₄OX₆L₄ molecule

Keywords: Crystal structure; Tetramers; Vector analyses; Copper(II) complexes; Hirshfeld surface

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-020-01257-4

Chemical Papers 74 (11) 3755–3766 (2020)