Structural studies on biaryl phosphines and palladium complexes composed of biaryl phosphines

Abstract

Pd-catalyzed cross-coupling processes have become one of the most important and useful class of transformations in organic synthesis in the past 25 years. Supporting ligand design has been crucial in developing more effective catalysts. One highly effective class of ligand is that of biaryl phosphines. Herein are presented experimental and theoretical structural data on this class of phosphine that aids in elucidating what aspects of ligand architecture are beneficial for catalyst stability and reactivity. Additionally, examples of traditionally difficult Suzuki-Miyaura reactions are presented along with a fluorescent sensor that can be used to monitor boronic acid consumption in Suzuki-Miyaura reactions in situ. Finally, a rationale behind the resistance of dialkylbiaryl phosphines toward oxidation by molecular oxidation is described. Chapter 1. Expansion of the Suzuki-Miyaura Coupling Reaction. Chapter 2. X-Ray Crystal Structures of Biaryl Phosphine Pd(0) and Pd(II) Complexes. Chapter 3. Structural Insights into Active Catalyst Structures and Oxidative Addition to Biaryl Phosphine-Palladium Complexes via Density Functional Theory and Experimental Studies.

(cont.) Chapter 4. Structural Insights into Amine Binding to Biaryl Phosphine-Palladium Complexes via Density Functional Theory and Experimental Studies. Chapter 5. Experimental and Theoretical Analysis of an Arene/Phosphine Ligated Pd(I) Dimer. Chapter 6. A Rationale for the Resistance of Dialkylbiaryl Phosphines Toward Oxidation by Molecular Oxygen. Chapter 7. Benchtop Monitoring of Reaction Progress via Visual Recognition with a Handheld UV Lamp: In Situ Sensing of Boronic Acids in the Suzuki-Miyaura Reaction.