Synthetic and structural studies of covalent and non-covalent interactions of ligands and metal center in platinum(II) complexes containing 2,2′- dipyridylamine or oxime ligands

Abstract

Coordination compounds of platinum(II) have played an important role in the development of coordination chemistry, and even nowadays new aspects of their structural diversity and reactivity continue to emerge. Applications of platinum(II) complexes span across various fields of modern technology and medicine. For this reason, the chemistry of platinum(II) complexes remains an important area of modern research. This dissertation aims to advance the knowledge of chemistry of this class of coordination compounds by classifying their chemical interactions in two domains: strength and location. The first chapter provides a short introduction into concepts of covalent and non-covalent interactions and coordination compounds. Next, platinum(II) complexes are introduced, and their key structural and electronic features are discussed utilizing very simple models. In the second chapter, the classification of various interactions of platinum(II) complexes into covalent and non-covalent by strength, and into those affecting ligands and the metal center by location is introduced. The resulting four types of interactions are discussed in more detail. The third chapter presents new contributions to each of the four fields. Benzylation of 2,2′-dipyridylamine (dpa) coordinated to platinum(II) involves covalent interactions of the ligands. Formation of hydrogen bonded supramolecular ensembles from oxime platinum(II) complexes and crown ether 18-crown-6 involves non-covalent interactions of the ligands. Oxidative chlorination of oxime platinum(II) complexes using N,N-dichlorotosylamide (dichloramine T) represents an example of covalent interactions of the metal center. Finally, unusual intramolecular Pt···I interactions in a platinum(II) complex with 2-iodobenzyldi(2-pyridyl)amine ligands involve non-covalent interactions of the metal center. The last chapter summarizes the key findings and conclusions of this work. Overall, the reported results demonstrate that the proposed classification of chemical interactions of platinum(II) complexes can be useful in development of novel reactivity and applications of these compounds. Keywords: coordination chemistry, platinum, non-covalent interactions, 2,2′- dipyridylamine, crown ether, N,N-dichlorotosylamide, dichloramine T