Tetrazines and N-Rich Organic Compounds Throughout the Fields of Materials Chemistry
Creators: name: Richardson, Paul
Publisher: name: Université d'Ottawa / University of Ottawa
Year: 2023
Subjects: subject: Inorganic Chemistry
subject: FOS: Chemical sciences
subject: Synthetic Inorganic Chemistry
subject: Tetrazines
subject: Molecular Magnetism
subject: Conductivity
subject: Energetic Materials

description: The field of materials chemistry encompasses a truly broad range of research interests. From discovering new compounds with physical properties such as luminescence, conductivity, or magnetism (or any combination thereof), to enhancing the efficiency of catalytical materials, to working closely with engineers in an effort to create novel devices, the number of avenues through which one may explore the field is practically endless. Using the chemist’s toolkit that is the periodic table, researchers may explicitly design synthetic protocols with the careful selection of starting materials (metals, ligands, solvents, etc.). The present Thesis aims to explore the ways that different N-rich organic compounds, primarily tetrazine-based molecules, react and coordinate with different metal ions, in order to target materials with properties ranging from single-molecule magnetism, to electron conductivity, to detonation performance. In Chapter 2, the simplest N-rich ligand employed throughout this work, 1,2,4,5-tetrazine, is combined with different copper metal salts, yielding coordination polymers that have the tetrazine in either in its complete form or a ring-opened form. These materials are characterized both structurally and physically, and their magnetic and conductive properties are analyzed. Further ring-opening behaviour was encountered in the work presented in Chapter 3, where interesting reactivity of the tetrazinyl moiety of the ligand 3,6-bis(pyrazinyl)-1,2,4,5-tetrazine (bpztz) is revealed in a new YbIII-based tetranuclear metal cluster. The compound is structurally and magnetically characterized to determine its single-molecule magnet behaviour, and its energy levels were assessed through both luminescence studies and theoretical calculations for comparison. Chapter 4 begins to explore the world of more nitrogen-rich tetrazine ligands. 3,6-dihydrazinyl-1,2,4,5-tetrazine (dhtz) is employed in conjunction with transition metal perchlorate salts, yielding a dimeric system. These compounds, while possessing moderate magnetic behaviour, are structurally characterized, and also undergo both qualitative and quantitative thermal analysis, illustrating the potential energetic properties of the system. The same ligand is further explored in Chapter 5, this time moving into the realm of rare-earth metals. A family of lanthanide-based coordination compounds are presented, including the first published crystal structure of a coordination compound employing the dhtz ligand. All compounds are analyzed magnetically, probing their behaviour under both direct current and alternating current external magnetic fields. Finally, this Thesis moves fully into the realm of energetic materials, aiming to synthesize compounds with not only high energetic performance, but with the potential to act as a ligand in coordination chemistry. In Chapter 6, the synthesis and characterization 2,4,6-tris(1H-tetrazol-5-yl)-1,3,5-triazine (H3TTT) and a family of metal-free organic salts are presented. The synthesized compounds were analyzed through various techniques (single crystal X-ray analysis, Hirshfeld analysis, NMR), thermal behaviour was analyzed, and the detonation parameters were calculated through theoretical frameworks. In summary, this Thesis intends to present the many various rich research avenues one may explore through tetrazines and other N-rich organic molecules, in the pursuit of rationally designing novel materials.