Development Of Catalytic Systems In Batch And Flow Using Dual Organocatalysts And Solid Packed-Bed Reactors
This dissertation discusses the development of complex catalytic systems in both batch and flow reactors using either organocatalysts or transition metal complexes with the future goal of developing multicatalyst cascade reactions. The work begins by providing a background of the various uses of multicatalyst systems in cascade reactions in both batch and flow. The observations gleaned from the group's work on the development of a multicatalyst system using a urea catalyst and L-proline in the known [alpha]-aminoxylation reaction spurred the development of a proline derivative/urea catalyst system in the formation of not only [alpha],[beta] and [beta],[gamma] unsaturated enones, but also substituted tetrahydrofuran derivatives. The second chapter illustrates both the scope of the transformation and provides a mechanistic understanding of the system. Then, wanting to transition proline catalyzed reaction to flow without the use of tethered catalysts or expensive soluble proline derivatives, we developed a new method for the direct use of solid proline. A soluble proline pre-catalyst was generated by passing reagents through a packed-bed of proline that was used in a downstream [alpha]-aminoxylation reaction. The final chapter extends this idea to the direct use of solid copper (I) oxide in the generation of Nheterocyclic carbene complexes. The utility of the carbene complexes was illustrated in the [beta]-borlyation of [alpha],[beta] unsaturated esters.