Design and characterisation of new organometallic based catalysts heterogenised on immobilised microporous materials

本研究计划的目标是合成（手性）Re(VII), Mo（VI）和W（VI）基配合物。首先，计划合成带有芳香n给体的ansa- bridging trioxorhenium（VII）复合物。到目前为止，芳香n给体是提高甲基三氧铈催化活性的最佳添加剂。作为一个额外的好处，手性可以在苯基的几个位置引入，或者在靠近金属中心的环桥或芳香配体上，通过环桥固定在金属上。导致最高对映体过量的催化剂分子可以进一步衍生化和优化。此外，还将制备手性Mo和W配合物。所有合成的化合物都将作为烯烃环氧化的催化剂进行测试，使用几种不同的烯烃，如环烯和1-辛烯，以及具有前手性烯烃碳的化合物，如苯乙烯、α-蒎烯、柠檬烯、莰烯等。此外，新的分子催化剂的合成和固定化具有足够高的负载，没有显著的浸出，目标是找到一种途径来生产高活性的催化剂，这种催化剂易于回收，适用于各种前手性底物，以产生具有良好选择性的预期产品。进一步计划用最先进的红外（IR）和拉曼光谱方法研究和监测以下过程：i)金属配合物在改性微孔和介孔材料固定表面上的异质化过程，ii)接枝方式和接枝后载体的性质，iii)接枝成功的确认，iv)基于分子结构研究的催化剂稳定性、选择性和活性的判断，以及通过红外、拉曼光谱端发射FT-IR检测多次催化运行后的变化。特别是关于非常现代的FTIR成像方法。

The goal of this research proposal is the synthesis of (chiral) Re(VII), Mo(VI) and W(VI) based complexes. First, it is planned to synthesise ansa-bridged trioxorhenium(VII) complexes with aromatic N-donor ligands. Aromatic N-donor ligands proved to be the best additives for enhancement of the catalytic activity of methyltrioxorhenium so far. As an added benefit, chirality could be introduced in several positions of the phenyl group, or, closer to the metal centre on the ansa bridge or the aromatic ligand, fixed to the metal by the ansa bridge. The catalyst molecules leading to the highest enantiomeric excess could be further derivatised and optimised. Additionally, chiral Mo and W complexes will be prepared. All synthesised compounds will be tested as catalysts of olefin epoxidation, applying several different olefins, e.g. cyclooctene, and 1-octene, but also compounds with prochiral olefin carbons, such as styrene, α-pinene, limonene, camphene etc. Additionally, the synthesis and immobilisation of new molecular catalysts to surfaces with sufficiently high loadings and without significant leaching is intended, with the goal of finding a route to produce highly active catalysts, which can easily be recycled and which are applicable for a variety of prochiral substrates to yield the intended products with good selectivity. It is further planned to study and monitor the following processes with the most advanced infrared (IR) and Raman spectroscopic methodologies: i) the heterogenisation process of metal complexes on immobilised surfaces of modified microporous and mesoporous materials, ii) the way of grafting and the nature of the support after grafting, iii) the confirmation of the successful grafting of the complexes, iv) the judgment about stability, selectivity and activity of catalysts based on molecular structural studies and detection of changes after several catalytic runs by infrared, Raman spectroscopy end emission FT-IR, with special respect to very modern FTIR imaging methods.