Beryllium Chemistry

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Due to the alleged toxicity of beryllium and its compounds, its chemistry is significantly underdeveloped. Therefore, the main aim of this project is to significantly increase the understanding of beryllium chemistry.Beryllium element bonds exhibit a highly covalent content due to the high electronegativity of beryllium in comparison to other metals. In combination with the lack of d-orbitals this result in an unusual electronic configuration. Thus beryllium compounds are used in many textbooks to illustrate bonding situations and models. But in reality there is little known about beryllium-element bonds. Therefore, the structure, stability and reactivity of organoberyllium compounds and of beryllium complexes with Lewis-bases will be investigated in the solid state and in solution. This will contribute to a more extensive understanding of the relation between the structure of beryllium compounds and their reactivity.Through the spectroscopic investigation of dynamic ligand exchange processes at the synthesized beryllium compounds, a comprehensive understanding of the underlying mechanism and of the electronic and steric influence on the ligand exchange in solution shall be obtained. This is regarded as essential to, on the one hand, estimate and harness the reactivity more precisely and, on the other hand, to better understand the beryllium coordination chemistry in the human body and herewith its “toxicity”.The Lewis-acidity of beryllium complexes will be studied extensively. The extremely high charge density at the beryllium atom promises high activity in the activation of small molecules with polarized bonds. Utilizing the relatively high stability of the Be-C-bond, N-Be- and P-Be-chelate ligands ought to be synthesized. Through the combination of electron-donating and –accepting coordination sites, the stabilization of electron-rich main group and transition metal compounds is anticipated.So far it is unclear how beryllium species are transported through the body and how they are bound. Therefore, beryllium complexes of amino acids, sugars and phosphoric acid esters will be investigated. Afterwards the coordination properties of specifically synthesized oligopeptides shall be studied to obtain knowledge about the selective binding in proteins. This promises a better understanding of metal induced immune reactions, which are poorly understood, even though these play a major role for aluminium based adjuvants in vaccinations. Finally, the gained findings will be used to prepare beryllium selective ligands, which can be applied in chelate therapy and for the treatment of waste water.