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

• Applicant: Professor Dr. Fritz E. Kühn
• Subject Area: Inorganic Molecular Chemistry - Synthesis and Characterisation
• Term: from 2011 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 193640454

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.

• DFG Programme: Research Grants
• International Connection: Hungary
• Participating Person: Professor Dr. János Mink