Beryllium Chemistry

由于据称铍及其化合物的毒性，其化学明显不发达。因此，这个项目的主要目的是显著增加对铍化学的了解。由于铍与其他金属相比具有较高的电负性，因此铍元素键显示出高共价含量。再加上d轨道的缺乏，这导致了一种不寻常的电子构型。因此，铍化合物在许多教科书中被用来说明成键情况和模型。但在现实中，人们对铍元素键知之甚少。因此，有机铍化合物和铍与Lewis碱的络合物的结构、稳定性和反应性将在固体和溶液中进行研究。这将有助于更广泛地了解铍化合物的结构与其反应活性之间的关系。通过对合成的铍化合物的动态配体交换过程的光谱研究，可以全面地了解其基本机理以及电子和空间位阻对溶液中配体交换的影响。这对于一方面更准确地估计和利用铍的反应性，另一方面更好地了解铍在人体内的配位化学以及由此产生的毒性是必不可少的。铍配合物的路易斯酸性将得到广泛的研究。铍原子上极高的电荷密度保证了具有极化键的小分子的高活性。利用Be-C键相对较高的稳定性，合成N-Be-和P-Be-螯合配体。通过给电子和接受电子配位的结合，有望稳定富电子主基和过渡金属化合物。到目前为止，还不清楚铍物种是如何在体内转运的，它们是如何结合的。因此，将对氨基酸、糖和磷酸酯的铍络合物进行研究。之后，应研究特定合成的寡肽的配位性质，以获得关于蛋白质中选择性结合的知识。这有助于更好地理解金属诱导的免疫反应，尽管这些反应在疫苗接种中对铝基佐剂起着重要作用，但人们对金属诱导的免疫反应知之甚少。最后，将所获得的结果用于制备铍的选择性配体，用于螯合治疗和废水处理。

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.