Zinc and copper are essential trace elements that are extremely important for all living
things. The fundamental motive for vast interest in their coordination chemistry stems
from the need for a deeper understanding of their biological role. A review of the
literature revealed that the chemistry of zinc(II) and copper(II) with quinaldinate (anion
of quinoline-2-carboxylic acid) is not well understood. Therefore, the reactions of
zinc(II) and copper(II) quinaldinate with cyclic amines and amino alcohols were
investigated. Systems with zinc(II) and amines in three different nitriles (acetonitrile,
propionitrile and benzonitrile) showed that zinc(II) can catalyze the reaction between a
cyclic amine and a nitrile, yielding an amidine. A variety of products have been
prepared: neutral complexes with quinaldinate and coordinated amines or amidines and
ionic compounds. The latter consisted of a protonated amine or amidine and an anionic
homoleptic complex with three quinaldinates. Analogous reactions with copper(II)
quinaldinate led to the isolation of complexes with coordinated amines. In the case of
copper(II), oxidation-reduction reactions occurred in some cases. In the case of
piperidine, the reduction was indeed proved by the crystal structure of a polycyclic
piperidine compound. Reactions with amino alcohols led to structurally very diverse
copper(II) compounds: mononuclear, binuclear and also one-dimensional polymeric
species with amino alcohols or amino alcoholates. Zinc(II) systems with amino alcohols
have shown that the amino alcohols can decompose to ammonia under forcing
conditions. The rich structural diversity of the products confirmed the high coordination
flexibility of the two metal ions. The same ligands can react differently in the presence
of zinc(II) or copper(II), with the reaction conditions also playing an important role.
More than a hundred compounds with nitrogen- and oxygen-donor ligands were
synthesized and characterized by different physicochemical methods: infrared
spectroscopy, nuclear magnetic resonance spectroscopy, elemental analysis, high-resolution mass spectrometry and single crystal X-ray structural analysis. In
collaboration with the research group of Dr. Joaquín López-Serrano (University of
Seville), theoretical DFT calculations were performed for some compounds, mainly to
compare their relative stabilities. In collaboration with the research group of Dr.
Rodolphe Clérac (University of Bordeaux), the magnetic properties of copper(II)
compounds with quinaldinate and amino alcohol ligands were measured and analyzed.
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