A series of phosphines with different heterocycles (pyridine and imidazole) possessing different substituents (alkyl and aryl) were synthesized. The phosphine ligands were reacted with different metal precursors to from organometallic complexes which were applied to catalysis. This dissertation describes, part of the discovery process of a uniquely active and selective catalyst for alkene isomerization and the importance of heterocyclic ring in the ligand, enhancing the acceleration of the reaction to almost 11,000 times faster than a non-heterocyclic analog. Further investigation of the isomerization catalyst, as a catalyst for cycloisomerization of alkynols led to discovery of the fact that a related alkyne hydration catalyst, reported by Dan Lev in 2004, was broadly useful in cycloisomerization reactions leading to synthesis of both indoles and benzofurans. A series of allylpalladium(II) chloride bifunctional phosphine complexes were also synthesized and characterized and eventually applied as catalysts for aryl amination reactions. Finally, two mechanistically distinct approaches to anti-Markovnikov alkene hydration using bifunctional ligands are described, which show promise for further development.

The research covered in this thesis involves studying and understanding the behavior of bifunctional ligands, specifically imidazolylphoshines. The major field of study is reaction of cyclopentadienyl ruthenium complexes with olefins, namely alkene isomerization. In these complexes, the basic nitrogen of the imidazolylphosphine is thought to deprotonate coordinated alkene intermediates reversibly, facilitating isomerization of terminal alkenes to yield internal alkenes selectively. The CpRu alkene isomerization catalyst is capable of moving double bonds as far as 30 positions; further mechanistic studies in presence of deuterium labeling as a tool, has led to development of hydrogen deuterium exchange of olefins at allylic positions. This finding supports the proposed mechanism and provides and outstanding deuteration at positions accessible by isomerization. The alkene isomerization catalyst can be used in a two-phase setting where the catalyst is dissolved in the organic layer and the non-toxic, non-flammable isotopic source (D2O) is immiscible with the organic layer. Using biphasic settings one can literally wash out reactive protons on the substrate without using organic solvents. In order to control high activity of alkene isomerization catalyst in absence of steric bulk provided by the substrate, bulkier phosphine ligands were synthesized and the activity of their metal complexes toward linear olefins was investigated. As a result, a family of catalysts that is capable of isomerizing unsubstituted linear alkenes to various mixtures have been established, where one can choose a complex to fit the needs of the process at hand. Further investigation with terminal alkenes bearing functional groups can be carried out to investigate whether mono-isomerization will still be the major transformation taking place, which is expected to give access to high-value 2-alkenes. To provide easy product-catalyst separation and potential wider application, the first syntheses of polymer-supported imidazolylphophines were developed, and the alkene isomerization catalyst was thus immobilized on polystyrene-based Merrifield resin. Compared to the homogeneous catalyst, the immobilized catalysts give the same high (E)-selectivity and conversion in isomerizations of terminal olefins to internal olefins with very low metal leaching from the insoluble support. Furthermore, use of organic solvents can be excluded and isomerization can be carried out in neat liquid organic substrates.

The field of transition metal catalysis has experienced incredible growth during the past decade. The reasons for this are obvious when one considers the world's energy problems and the need for new and less energy demanding syntheses of important chemicals. Heterogeneous catalysis has played a major industrial role; however, such reactions are generally not selective and are exceedingly difficult to study. Homogeneous catalysis suffers from on-site engineering difficulties; however, such reactions usually provide the desired selectivity. For example, Monsanto's synthesis of optically-active amino acids employs a chiral homogeneous rhodium diphosphine catalyst. Industrial uses of homogeneous catalyst systems are increasing. It is not by accident that many homogeneous catalysts contain tertiary phosphine ligands. These ligands possess the correct steric and electronic properties that are necessary for catalytic reactivity and selectivity. This point will be emphasized throughout the book. Thus the stage is set for a comprehensive be treatment of the many ways in which phosphine catalyst systems can designed, synthesized, and studied.

CHAPTER 1. This chapter introduces the field of study and motivations steering the direction of development. The topics of catalysis and bifunctional catalysis are discussed. CHAPTER 2. This chapter describes the development of biaryl phosphines containing functionalization with a pendent base for use in gold catalyzed organic reactions. This chapter starts with development of synthetic methods for high efficiency in the synthesis of new iterations on the chemical structure. The use of high throughput screening for reaction discovery is discussed and the result from our trials is discussed. Evaluation of the different ligand candidates is done through NMR spectroscopic studies on two reactions. The first reaction studied is carboxylic acid addition to terminal alkynes. The second reaction studied is isomerization of alkynes. CHAPTER 3. This chapter describes the synthesis of hydrogen-bond-donor-functionalized ferrocenyl bisphosphines, and studies on the coordination chemistry of the novel bisphosphines with platinum and nickel. Development of the synthetic route to yielding the target compounds was necessary, and the major points of concern are discussed. Studies on the coordination chemistry of the ferrocenyl bisphosphines with platinum and nickel are discussed

Written by experts in the field, this is a much-needed overview of the rapidly emerging field of cooperative catalysis. The authors focus on the design and development of novel high-performance catalysts for applications in organic synthesis (particularly asymmetric synthesis), covering a broad range of topics, from the latest progress in Lewis acid / Brønsted base catalysis to e.g. metal-assisted organo catalysis, cooperative metal/enzyme catalysis, and cooperative catalysis in polymerization reactions and on solid surfaces. The chapters are classified according to the type of cooperating activating groups, and describe in detail the different strategies of cooperative activation, highlighting their respective advantages and pitfalls. As a result, readers will learn about the different concepts of cooperative catalysis, their corresponding modes of operation and their applications, thus helping to find a solution to a specific synthetic catalysis problem.

Phosphines as Reagents and Catalysts in Organic Synthesis provides comprehensive coverage of metal-free organic reactions with phosphines as reagents or catalysts as well as their synthetic uses. The work begins with a short historical overview of the use of phosphines in metal-free organic reactions, followed by details of their physical properties, as well as the source and preparation methods for representative phosphines and chiral variants. The applications of phosphines as reagents and catalysts in organic synthesis are discussed, along with case studies organized according to reaction type. These reactions include halogenation under Appel conditions, Wittig reaction, Staudinger reaction, Mitsunobu reaction, alcohol acylation and kinetic resolution, Rauhut-Currier reaction, Morita-Baylis-Hillman reaction, conjugate addition, umpolung additions, annulation reactions, allylic substitution, allylic amination, and isomerization reactions. For each reaction an overview of the state of art is presented along with the reaction data, enantioselective version using chiral phosphine, and its application in the synthesis of biologically active compounds and total synthesis of natural products. The work concludes with a summary that highlights the most promising reactions for future development in this field of research. Researchers, graduate students and undergraduates working in organic synthesis will find this work to be an invaluable resource. Covers the application of organic reactions involving phosphine as reagents and catalysts in organic synthesis and biological chemistry Features synthetic methods for creating heterocyclic compounds Includes comprehensive coverage of organic reactions and reaction mechanisms involving phosphine as reagents and catalysts

The series Topics in Current Chemistry Collections presents critical reviews from the journal Topics in Current Chemistry organized in topical volumes. The scope of coverage is all areas of chemical science including the interfaces with related disciplines such as biology, medicine and materials science. The goal of each thematic volume is to give the non-specialist reader, whether in academia or industry, a comprehensive insight into an area where new research is emerging which is of interest to a larger scientific audience.Each review within the volume critically surveys one aspect of that topic and places it within the context of the volume as a whole. The most significant developments of the last 5 to 10 years are presented using selected examples to illustrate the principles discussed. The coverage is not intended to be an exhaustive summary of the field or include large quantities of data, but should rather be conceptual, concentrating on the methodological thinking that will allow the non-specialist reader to understand the information presented. Contributions also offer an outlook on potential future developments in the field.The chapter "Enamine/Transition Metal Combined Catalysis: Catalytic Transformations Involving Organometallic Electrophilic Intermediates" is available open access under a CC BY 4.0 License via link.springer.com.