New Recyclable Phosphorous Ligands for Regio- and Stereocontrol in Homogeneous Catalysis

• Applicants: Professor Dr. Peter Eilbracht; Professor Dr. Rainer Haag
• Subject Area: Organic Molecular Chemistry - Synthesis and Characterisation
• Term: from 2006 to 2010
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 22730784

Multi-component and multi-step conversions as one-pot reaction sequences are attractive tools in modern synthetic chemistry. Many of these methods require multifunctional homogeneous catalysts. Immobilization of homogeneous catalysts on supports overcomes the inherent problems of separation and reuse. The project aims at development of novel immobilized ligand systems for homogeneous catalysis in membrane reactors. Immobilization is achieved with soluble, (ultra)filterable and reusable dendritic polyglycerols and the construction of functional shells. Applications of these systems for proof of principle is first tested with some achiral and chiral standard ligands. New convergent dendrimer and dendron syntheses are planned via combinations of acrylonitrile Michael addition/nitrile reduction sequences (Vögtle method) with hydroformylation/reductive amination (hydroaminomethylation). Endcapping of the dendrons with P or N/O functionalities including enantiomerically pure systems supplies the ligands for catalyst immobilization. Furthermore synthesis, catalytic evaluation of new P chirogenic systems is planned as well as their immobilization to dendritic polyglycerols and polyamines according to the above mentioned methods. The new immobilized ligands are to be tested in membrane reactors or similar flow systems for continuous production or library syntheses via homogeneous catalysis in order to realize new sustainable processes.

• DFG Programme: Research Grants