Synthesis, characterization and applications of complexes with transition metal ions in d6, d8 and d10 configuration, with nitrogen heterocyclic ligands containing pyridinic nuclei.

This PhD project in Chemical Sciences and Technologies focused on the synthesis, reactivity and applications of various nitrogen-containing heterocyclic ligands containing pyridine nuclei and their derivatives with transition metal ions, mainly in d8 configuration, including Pd(II), Pt(II) and Au(III). The ligands studied belong to the following classes: i. 2-substituted pyridines and 6-substituted 2,2'-bipyridines ii. 3-substituted 1-(2-pyridyl)imidazo[1,5-a]pyridines iii. 1,3-bis-(2-pyridyl)benzene (pincer ligands) and 1,2-bis-(2-pyridyl)benzene In general, all ligands, some already known and others new, were extensively characterized in solution using mono-dimensional and bi-dimensional NMR spectroscopic techniques in order to assign signals to all protons. In some cases, it was possible to resolve the structure using X-rays. The coordination behaviour of the synthesized ligands with transition metal ions such as Pd(II), Pt(II) and Au(III) was studied, leading to the synthesis of adduct complexes and cyclometallated derivatives obtained by reacting the above ligands with metal salts or suitable metal intermediates. The experimental conditions used sought to favour cyclometallation reactions in cases where the ligand allowed this. The study of the reactivity and biological and catalytic applications of the compounds obtained and described was carried out partly at the Department of Sassari (reactivity) and partly at the Department of Chemistry School of Natural Sciences of Technical University of Munich (TUM) under the supervision of Prof. Angela Casini (biological activity, in particular testing anti-tumour activity on certain cell lines).