Mechanistic Studies of Nucleophilic Organocatalysis by N-Heterocyclic Carbenes

Nature uses complex molecules known as enzymes as highly specific catalysts for a multitude of chemical transformations that are essential for biological processes. Although efficient, enzyme reactions often need another molecule, known as a co-factor, to promote specific transformations. In order to further our understanding of these processes, synthetic chemists are constantly trying to engineer artificial molecules that have the ability to mimic enzymatic transformations. There is much current interest in one specific branch of this area of research, which is commonly known as organocatalysis . This technique uses small organic molecules instead of enzymes in order to carry out selective chemical reactions. This proposal aims to develop a fundamental understanding of how one particular class of a simple organic molecule, known as an N-heterocyclic carbene, is able to catalyse a wide range of selective chemical transformations. Nature uses a carbene equivalent as a co-factor in a range of chemical transformations and this proposal seeks to understand why they can be used in the laboratory. By understanding how each step in a particular process works, and by comprehending how the rate of each step changes with a change in catalyst structure, we hope to be able to prepare highly selective and efficient catalysts for the future.