Visible light-mediated cyclizations of cyclic enones

The work outlined in this thesis covers the development of visible light-mediated cyclizations of cyclic enones. Chapter one provides an overview of photochemical cyclizations, focusing on visible light-mediated cyclizations using triplet energy transfer from a suitable sensitizer, as well as an overview of the photochemical cyclizations of cyclic enones. Chapter two discusses the development of a visible light-mediated intramolecular arylation of cyclic 2-arylheteroenones to generate a wide range of cis-fused heterocycles. Chapter three details efforts into the photochemical synthesis of spirocyclic compounds via intramolecular hydrogen atom abstraction using a cyclic enone chromophore. Chapter four discusses the development of a visible light-mediated spirocyclization of cyclic 2-amidoenones. After initial optimization, the scope and scalability of the reaction was explored, and derivatization of the products investigated. Subsequent mechanistic experiments provided insight into the high diastereoselectivity of the reaction. Chapter five looks at applications of the previously developed reactions to acyclic chromophore systems, and the challenges present in this modification