UC Berkeley

This thesis represents the efforts to develop new catalytic methods, and to discover new organic materials. These efforts were driven by mechanistic thinking in organic and organometallic chemistry.

Chapter 1 offers a historical overview of how mechanistic understandings drive reaction development and inspire the development in other related fields such as chemical biology and materials science.

Chapter 2 discusses a new strategy to activate transition metal complexes by hydrogen-bond donors (HBDs). Anion binding catalysis using HBDs, Au(I)/Au(III) redox chemistry, and the prevalence of anion abstraction in Au(I) catalysis are introduced as a foundational design principle of the new strategy. Attempts to achieve anion abstraction from Au(I) and Au(III) complexes using this strategy are then presented. This led to the development of an enantioselective intermolecular Au(I)-catalyzed hydro(hetero)arylation reaction of allenes. Experimental and computational studies showed an interplay of non-covalent interactions that led to the observed enantioselectivities. Computational studies on the origin of enantioselectivities were conducted in collaboration with ‪Dr. Binh Khanh Mai from Prof. Peng Liu’s lab at University of Pittsburgh.‬‬‬‬‬‬‬‬‬‬‬‬

Chapter 3 focuses on the design and synthesis of cyclic acylsilanes and their applications in ring-opening metathesis polymerization (ROMP). First, photochemical reactivities of acylsilanes and how these reactivities can be translated to macroscopic properties, such as degradability of materials, are discussed. The synthesis of eight-membered-ring acylsilane-based cyclic olefins as monomers for ROMP led to photodegradable polymers. Photochemical ring expansion reactions of the cyclic acylsilane were also discovered. The resulting product holds promise to yield degradable polymers with controlled release properties. This work was done in collaboration with Mufeng Wei, Emma Vargo, and Yiwen Qian from Prof. Ting Xu’s lab at UC Berkeley.

Chapter 4 describes the discovery of a new linker for covalent organic frameworks (COFs), namely nitrone linkages. This was driven by the diverse reactivities of nitrone functionalities. The resulting COFs were found to undergo a photochemical isomerization reaction. This work was done in collaboration with Dr. Daria Kurandina, and Dr. Wentao Xu from Prof. Omar Yaghi’s lab at UC Berkeley.