Chiral phosphines are central to the development of enantioselective organic transformations because they are used extensively as ligands or organocatalysts. The work presented in this thesis describes efforts to develop new phosphine ligands, either through supramolecular self-assembly or through novel synthetic methods. Chapter 1 describes the development of chiral phosphines that self-assemble through reversible covalent iminoboronate linkages. By utilizing a facile condensation process driven by an intramolecular B-N interaction, a 100-ligand library was generated. Incorporation of various 2-formylarylboronic acids, chiral aminophosphines and vicinal diols, resulted in phosphine ligands with great structural diversity. The self-assembled ligands were employed in transition metal-catalyzed enantioselective transformations. Likely coordination modes and ligand decomposition pathways in the presence of transition metals are discussed. Synthesis of chiral beta-aminophosphines possessing different diarylphosphino moieties is presented in Chapter 2. The protocol made use of the nucleophilic ring-opening of sulfamidates derived from serval optically pure amino alcohols. Through the use of phosphine oxides as 'masked' phosphine equivalents, purification and isolation of intermediates from otherwise challenging synthetic steps were made possible. P- versus O-alkylation in the reactions of diarylphosphinites with sulfamidates will also be discussed. ii Chapter 3 describes an extension of the synthesis of beta-aminophosphines described in Chapter 2 to P-chiral variants. Treatment of an enantiopure sulfamidate with a racemic unsymmetrical secondary phosphine oxide resulted in diastereomeric intermediates that could be separated either by fractional recrystallization or silica gel chromatography. A BH3-mediated stereospecific phosphine oxide reduction was developed and implemented to convert these adducts to the corresponding diastereomerically enriched beta-aminophosphines. Finally, Chapter 4 describes the application of the thiourea derivatives of these P-chiral aminophosphines as organocatalysts. Evaluation of their catalytic performance in enantioselective Morita-Baylis-Hillman reactions revealed that the P-chiral catalysts afforded superior levels of selectivity compared to the non-P-chiral variant. Additionally, the spatial disposition of the two different P-aryl groups was found to influence catalytic activity as a result of matching/mismatching effects.

Chiral Phosphorous Based Ligands in Earth-Abundant Transition Metal Catalysis summarizes the most significant progress in the field of chiral phosphine ligand chemistry and a broad range of earth-abundant transition metal/chiral phosphine ligand-catalyzed enantioselective transformations. The book provides an authoritative and in-depth understanding of important topics about asymmetric catalysis based on earth-abundant transition metals/chiral phosphine ligands, making it ideal for organic chemistry researchers working in the field of asymmetric catalysis, synthetic methodologies and total synthesis.The development of new chiral phosphine ligands to achieve precise stereo control in many earth-abundant transition metal-catalyzed reactions is a very important field in organic synthesis, materials science and medicinal chemistry. The asymmetric synthesis promoted by transition metal/chiral phosphine ligands provides one of the most ideal ways to produce valuable optically active chemicals. - Includes a discussion of state-of-the-art asymmetric organic reactions mediated by earth-abundant transition metals and chiral phosphine ligands - Features the progress and the prospect of chiral phosphine ligands in asymmetric transition metal catalysis - Covers the asymmetric reactivity modes of earth-abundant transition metals and phosphine ligands

Over the last 60 years the increasing knowledge of transition metal chemistry has resulted in an enormous advance of homogeneous catalysis as an essential tool in both academic and industrial fields. Remarkably, phosphorus(III) donor ligands have played an important role in several of the acknowledged catalytic reactions. The positive effects of phosphine ligands in transition metal homogeneous catalysis have contributed largely to the evolution of the field into an indispensable tool in organic synthesis and the industrial production of chemicals. This book aims to address the design and synthesis of a comprehensive compilation of P(III) ligands for homogeneous catalysis. It not only focuses on the well-known traditional ligands that have been explored by catalysis researchers, but also includes promising ligand types that have traditionally been ignored mainly because of their challenging synthesis. Topics covered include ligand effects in homogeneous catalysis and rational catalyst design, P-stereogenic ligands, calixarenes, supramolecular approaches, solid phase synthesis, biological approaches, and solubility and separation. Ligand families covered in this book include phosphine, diphosphine, phosphite, diphosphite, phosphoramidite, phosphonite, phosphinite, phosphole, phosphinine, phosphinidenene, phosphaalkenes, phosphaalkynes, P-chiral ligands, and cage ligands. Each ligand class is accompanied by detailed and reliable synthetic procedures. Often the rate limiting step in the application of ligands in catalysis is the synthesis of the ligands themselves, which can often be very challenging and time consuming. This book will provide helpful advice as to the accessibility of ligands as well as their synthesis, thereby allowing researchers to make a more informed choice. Phosphorus(III) Ligands in Homogeneous Catalysis: Design and Synthesis is an essential overview of this important class of catalysts for academic and industrial researchers working in catalyst development, organometallic and synthetic chemistry.