Copper and rhodium catalyzed dynamic kinetic asymmetric transformations

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The development of catalytic methods for asymmetric synthesis is one of the foremost achievements in chemistry. Asymmetric catalysis is a key technology in the efficient development of new medicines, fragrances, polymers, materials and catalysts. While many broadly useful methods for catalytic asymmetric oxidation and reduction exist, there are far fewer asymmetric methods for forming carbon-carbon bonds, which make up the framework of organic molecules. Typically in asymmetric catalysis, prochiral (usually flat) starting materials are used and the catalyst selects one side of the starting material for a reaction that introduces chirality and selectively produces one enantiomer of product. Where an 'enantiomer' is a specific 3d orientation, often described as one "hand" where there are two possible hands, and the hands or enantiomers are non-superimposible mirror images of each other. This project aims to develop new asymmetric reactions where racemic starting material (a 50:50 mixture of two enantiomers, or 'hands') is converted selectively into one enantiomer of a product at the same time that a new carbon-carbon bond forms. This is a much less straightforward process than using prochiral starting materials and there are only very few types of reaction that can use this strategy. However, as there are many more racemic than prochiral molecules, methods that use racemic starting materials would be very useful in asymmetric synthesis. Catalytic asymmetric carbon-carbon bond forming methods that use racemic starting materials are known, but these are limited to the combination of a precious metal catalyst (palladium, iridium, etc.) and an especially stabilized reaction partner. Here we will develop new methods that don't require stabilized reaction partners. We will use nuclear magnetic resonance spectroscopy to study the new reactions and try to understand the chemical pathways that are occurring. We expect that the information from the spectroscopic studies will be very useful in designing additional reactions. Overall, these studies will provide important new ways to rapidly synthesize a wide range of molecules with a wide variety of uses.