Download or read book Air stable Palladium II Precatalysts written by Kerry Lynn Barnett and published by . This book was released on 2017 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: Palladium catalyzed cross-coupling reactions are a versatile tool in organic chemistry to produce small molecules. Current research interests involve the development of new catalyst systems for various palladium catalyzed reactions. Previous work has suggested the active species for palladium-catalyzed cross-coupling reactions to be a mono-ligated palladium(0) species when sterically demanding ligands are used. Therefore, the my work focused on the synthesis of precatalysts with an established 1:1 L:Pd. Specifically, we were focused on the synthesis of mono-ligated palladium(II) precatalysts of general formula [(R_3P)PdCl_2]_2, using di-tert-butylneopentylphosphine (DTBNpP), tert-butyldineopentylphosphine (TBDNpP), and trineopentylphosphine (TNpP) as ligands. Under optimized conditions, both [(DTBNpP)PdCl_2]_2 and [(TNpP)PdCl_2]_2 were effective precatalysts for the Suzuki cross-coupling of a wide range of aryl bromides. Comparison studies with the air-stable precatalysts versus the in-situ generated catalyst showed the precatalysts to have improved conversions and higher rates of reaction under both inert and ambient atmospheres. The precatalyst activation pathways were investigated by 31P NMR spectroscopy. The spectra obtained from 31P NMR experiments revealed a side reaction resulting in a catalytically inactive palladacycle species. The results obtained from the mechanistic investigations led to further optimization of reaction conditions to decrease the amounts of catalytically inactive side products formed.

Download or read book Synthesis and Application of Air Stable Secondary Phosphine Oxide Oxime and Amine Phosphine Palladium II Complexes in Transfer Hydrogenation and Cross Coupling Reactions written by Jason E. Bara and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Catalysis plays an important role in industry as over 90% of chemical processes involve catalysts in at least one step. Historically, heterogeneous catalysis has been more commonly employed in industry as these systems tend to be more economically friendly and environmentally benign. However, improved procedures for homogeneous catalysis using organocatalysts and organometallic compounds has generated increased interest in homogeneous systems. Organometallic compounds offer higher specific activities and selectivity in comparison to traditional heterogeneous systems. These qualities make homogeneous catalysis particularly attractive for the production of fine chemicals, pharmaceuticals, and natural products. Ligand design is critical for the development of homogeneous catalysts. For late-transition-metal-catalyzed cross-coupling reactions that rely on C-X or C-H oxidative addition, strongly electron-donating and sterically demanding ligands afford the most efficient systems. Several privileged classes of ligands have been identified and employed in palladium-catalyzed reactions. These systems are believed to promote their respective reactions through a monoligated palladium(0) species. Our work focused on the development of precatalysts with an established 1:1 L:Pd ratio. Specifically, we were interested in the synthesis of palladium(II) precatalysts with the general formula (R3P)Pd(amine)Cl2, using di-tert-butylneopentylphosphine and trineopentylphosphine. Under optimized conditions, the precatalysts were effective for the Buchwald-Hartwig amination of aryl bromides and aryl chlorides. We discovered that the identity of the amine ligand significantly impacts catalyst efficiency with linear primary alkyl amines providing the most active catalysts. A comparison study between the air-stable precatalysts and in situ generated catalysts showed improved activity for the precatalysts. Typically, the aforementioned privileged classes of ligands behave as spectators during the bond activation process. However, ligands containing functional groups that introduce acidic/basic sites proximal to the metal center can participate through acid-base interactions with the substrates. Multifunctional ligands have proven to be efficient in numerous transition-metal-catalyzed processes. We focused on synthesizing secondary phosphine oxide and oxime ligands that contain a basic hydroxyl group(s) upon complexation. The synthesis of oxime-derived palladacycles was facile and efficient. These catalysts efficiently facilitated the transfer hydrogenation of benzophenone. The active species is believed to be a three- or four-atom palladium cluster resulting from decomposition of the palladium-oxime complex.

Download or read book Catalysis from A to Z written by Boy Cornils and published by John Wiley & Sons. This book was released on 2020-01-13 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides a complete and accessible A to Z collection of information on catalysis This updated and enlarged must-have edition of a classic book on catalysis explains the important terms of all aspects of the subject - including biocatalysis, homogeneous catalysis, heterogeneous catalysis - as well as the terms associated with it. It also looks at related topics like spectroscopy or analytical methods. Featuring 20% more content than the previous edition, it comprehensively covers the topic in a clear and concise manner, and includes abbreviations, brief biographic entries of important scientists who have worked in catalysis, trade names, important catalytic processes, named reactions, reactions, and other important keywords in the general field of catalysis. Written by more than 200 top scientists and with more than 15,000 entries on all aspects of catalysis, Catalysis from A to Z: A Concise Encyclopedia, 5th Edition is filled with figures, tables, cross-references, and references. It covers acids, ligands, catalytic reactions in organic synthesis, kinetics and thermodynamics of catalytic reactions, and catalyst labeling. The book also looks at theoretical backgrounds of catalytic reactions, industrial catalytic processes, autoclaves, colloids, nanomaterials, spectroscopically methods for catalyst analysis, and more. Provides all the knowledge scientists need to know about homogeneous, heterogeneous, and biochemical catalysis Includes more than 15,000 keywords in compact entries Newly updated and expanded edition of the bestselling classic Comprehensive, succinct, and easy to use Edited by an experienced team of top editors and authors with contributions from over 200 scientific experts Offers German and French translations of the keywords to help students and non-native English speakers Catalysis from A to Z: A Concise Encyclopedia is an ideal resource for every student, chemist, scientist, and engineer involved in catalytic chemistry, chemical engineering, biochemistry, organic chemistry, and more.

Download or read book Palladacycles written by Anant Kapdi and published by Elsevier. This book was released on 2019-06-15 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Palladacycles: Catalysis and Beyond provides an overview of recent research in palladacycles in catalysis for cross-coupling and similar reactions. In the quest for developing highly efficient and robust palladium-based catalysts for C-C bond formation via cross-coupling reactions, palladacycles have played a significant role. In recent years, they have found a wide variety of applications, ranging from catalysts for cross-coupling and related reactions, to their more recent application as anticancer agents. This book explores early examples of the use of palladacyclic complexes in catalysis employing azobenzene and hydrazobenzene as coordinating ligands. Its applications in processes such as selective reduction of alkenes, alkynes, or nitroalkanes are also covered. Palladacycles: Catalysis and Beyond reveals the tremendous advances that have taken place in the potential applications of palladacycles as versatile catalysts in academia and industry. It is a valuable resource for synthetic chemists, organometallic chemists, and chemical biologists.

Download or read book Modern Organonickel Chemistry written by Yoshinao Tamaru and published by John Wiley & Sons. This book was released on 2006-03-06 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organonickel chemistry plays an increasingly important role in organic chemistry, and interest in this topic is now just as keen as in organopalladium chemistry. While there are numerous, very successful books on the latter, a book specializing in organonickel chemistry is long overdue. Edited by one of the leading experts in the field, this volume covers the many discoveries made over the past 30 years, and previously scattered throughout the literature. Active researchers working at the forefront of organonickel chemistry provide a comprehensive review of the topic, including cross-coupling reactions, asymmetric synthesis and heterogeneous catalysis reaction types. A must-have for both organometallic chemists and synthetic organic chemists.

Download or read book Palladium Catalyzed Coupling Reactions written by Árpád Molnár and published by John Wiley & Sons. This book was released on 2013-02-14 with total page 531 pages. Available in PDF, EPUB and Kindle. Book excerpt: This handbook and ready reference brings together all significant issues of practical importance in selected topics discussing recent significant achievements for interested readers in one single volume. While covering homogeneous and heterogeneous catalysis, the text is unique in focusing on such important aspects as using different reaction media, microwave techniques or catalyst recycling. It also provides a comprehensive treatment of key issues of modern-day coupling reactions having emerged and matured in recent years and emphasizes those topics that show potential for future development, such as continuous flow systems, water as a reaction medium, and catalyst immobilization, among others. With its inclusion of large-scale applications in the pharmaceutical industry, this will equally be of great interest to industrial chemists. From the contents * Palladium-Catalyzed Cross-Coupling Reactions - A General Introduction * High-turnover Heterogeneous Palladium Catalysts in Coupling Reactions: the Case of Pd Loaded on Dealuminated Y Zeolites Palladium-Catalyzed Coupling Reactions with Magnetically Separable Nanocatalysts * The Use of Ordered Porous Solids as Support Materials in Palladium-Catalyzed Cross-Coupling Reactions * Coupling Reactions Induced by Polymer-Supported Catalysts * Coupling Reactions in Ionic Liquids * Cross-Coupling Reactions in Aqueous Media * Microwave-Assisted Synthesis in C-C and C-Heteroatom Coupling Reactions * Catalyst Recycling in Palladium-Catalyzed Carbon-Carbon Coupling Reactions * Nature of the True Catalytic Species in Carbon-Carbon Coupling Reactions with * Heterogeneous Palladium Precatalysts * Coupling Reactions in Continuous Flow Systems * Large-Scale Applications of Palladium-Catalyzed Couplings in the Pharmaceutical Industry

Download or read book Synthetic Methods in Drug Discovery written by David C Blakemore and published by Royal Society of Chemistry. This book was released on 2016-07-15 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt: Synthetic Methods in Drug Discovery Volume 1 focusses on the hugely important area of transition metal mediated methods used in industry. Current methods of importance such as the Suzuki-Miyaura coupling, Buchwald-Hartwig couplings and CH activation are discussed. In addition, exciting emerging areas such as decarboxylative coupling, and the uses of iron and nickel in coupling reactions are also covered. This book provides both academic and industrial perspectives on some key reactions giving the reader an excellent overview of the techniques used in modern synthesis. Reaction types are conveniently framed in the context of their value to industry and the challenges and limitations of methodologies are discussed with relevant illustrative examples. Edited and authored by leading scientists from both academia and industry, this book will be a valuable reference for all chemists involved in drug discovery as well as postgraduate students in medicinal chemistry.

Download or read book Applied Cross Coupling Reactions written by Yasushi Nishihara and published by Springer Science & Business Media. This book was released on 2012-12-14 with total page 247 pages. Available in PDF, EPUB and Kindle. Book excerpt: “Applied Cross-Coupling Reactions” provides students and teachers of advanced organic chemistry with an overview of the history, mechanisms and applications of cross-coupling reactions. Since the discovery of the transition-metal-catalyzed cross-coupling reactions in 1972, numerous synthetic uses and industrial applications have been developed. The mechanistic studies of the cross-coupling reactions have disclosed that three fundamental reactions: oxidative addition, transmetalation, and reductive elimination, are involved in a catalytic cycle. Cross-coupling reactions have allowed us to produce a variety of compounds for industrial purposes, such as natural products, pharmaceuticals, liquid crystals and conjugate polymers for use in electronic devices. Indeed, the Nobel Prize for Chemistry in 2010 was awarded for work on cross-coupling reactions. In this book, the recent trends in cross-coupling reactions are also introduced from the point of view of synthesis design and catalytic activities of transition-metal catalysts.

Download or read book Palladium in Organic Synthesis written by Jiro Tsuji and published by Springer Science & Business Media. This book was released on 2005-07-06 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: with contributions by numerous experts

Download or read book Metal catalyzed Cross coupling Reactions written by François Diederich and published by John Wiley & Sons. This book was released on 2008-07-11 with total page 540 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon-carbon bond forming reactions are arguably the most important processes in chemistry, as they represent key steps in the building of complex molecules from simple precursors. Among these reactions, metal-catalyzed cross-coupling reactions are extensively employed in a wide range of areas of preparative organic chemistry, ranging from the synthesis of complex natural products, to supramolecular chemistry, and materials science. In this work, a dozen internationally renowned experts and leaders in the field bring the reader up to date by documenting and critically analyzing current developments and uses of metal-catalyzed cross-coupling reactions. A particularly attractive and useful feature, that enhances the practical value of this monograph, is the inclusion of key synthetic protocols, in experimental format, chosen for broad utility and application. This practice-oriented book can offer the practitioner short cuts to ensure they remain up-to-date with the latest developments.

Download or read book Palladium Catalyzed Modification of Nucleosides Nucleotides and Oligonucleotides written by Anant R. Kapdi and published by Elsevier. This book was released on 2018-06-04 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: Palladium-Catalyzed Modification of Nucleosides, Nucleotides and Oligonucleotides describes the procedures and protocols related to the modification of nucleosides, nucleotides and oligonucleotides via Pd-mediated cross-coupling processes. The book highlights the growing area of nucleic acid modification and how Pd-mediated coupling reactions can assist this development. Users will find key synthetic protocols for these reactions in this latest volume in the Latest Trends in Palladium Chemistry series. As most of the research in the field of antiviral agents has centered on the use of modified nucleosides that have exhibited promising activity, this book provides an up-to-date reference for both professionals in industry and other interested parties. Provides synthetic routes for useful nucleoside molecules, information otherwise found only through time-consuming literature searches Covers metal-mediated and metal-catalyzed cross coupling processes of nucleosides and related compounds Includes Suzuki-Miyaura, Stille and Sonogashira reactions, as well as C-H bond functionalization Highlights the growing area of nucleic acid modification and how Pd-mediated coupling reactions can assist

Download or read book Ligand Design in Metal Chemistry written by Mark Stradiotto and published by John Wiley & Sons. This book was released on 2016-09-01 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: The design of ancillary ligands used to modify the structural and reactivity properties of metal complexes has evolved into a rapidly expanding sub-discipline in inorganic and organometallic chemistry. Ancillary ligand design has figured directly in the discovery of new bonding motifs and stoichiometric reactivity, as well as in the development of new catalytic protocols that have had widespread positive impact on chemical synthesis on benchtop and industrial scales. Ligand Design in Metal Chemistry presents a collection of cutting-edge contributions from leaders in the field of ligand design, encompassing a broad spectrum of ancillary ligand classes and reactivity applications. Topics covered include: Key concepts in ligand design Redox non-innocent ligands Ligands for selective alkene metathesis Ligands in cross-coupling Ligand design in polymerization Ligand design in modern lanthanide chemistry Cooperative metal-ligand reactivity P,N Ligands for enantioselective hydrogenation Spiro-cyclic ligands in asymmetric catalysis This book will be a valuable reference for academic researchers and industry practitioners working in the field of ligand design, as well as those who work in the many areas in which the impact of ancillary ligand design has proven significant, for example synthetic organic chemistry, catalysis, medicinal chemistry, polymer science and materials chemistry.

Download or read book The Stille Reaction written by Vittorio Farina and published by John Wiley & Sons. This book was released on 1998-09-18 with total page 676 pages. Available in PDF, EPUB and Kindle. Book excerpt: Die Stille-Reaktion ist eine der sehr wenigen Reaktionen, in denen unter milden Bedingungen Kohlenstoff-Kohlenstoff-Bindungen geknüpft werden können. Man verwendet die Reaktion häufig in der Synthese komplizierter Moleküle zur Verknüpfung größerer Molekülbausteine. Die Autoren diskutieren vom präparativen Standpunkt aus Grenzen, Einflüsse, strukturelle Effekte und die Wahl der geeigneten Reaktionsbedingungen. Mit ausführlichen Vorschriften und vielen Beispielen. (11/98)

Download or read book New Discoveries on the Hydride Elimination written by Thomas M. Gogsig and published by Springer. This book was released on 2012-09-06 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work presented in Thomas M. Gøgsig's thesis deals with the discovery of new metal-catalyzed transformations ranging from Kumada-, Heck- and Suzuki-type reactions. The thesis starts with a formidable introduction to Pd-catalyzed cross-coupling reactions. New results have been obtained on: (i) Pd-catalyzed 1,2-migration reactions, (ii) Pd-catalyzed Heck reactions employing heteroaromatic tosylates, (iii) Ni-catalyzed Heck reactions, and (iv) Pd-catalyzed carbonylative Heck reaction. Metal-catalyzed cross-coupling reactions are today a highly competititve field (the 2010 Nobel Prize in Chemistry was awarded "for palladium-catalyzed cross couplings in organic synthesis", the 2001 and 2005 Nobel Prizes in closely related fields). Thomas M. Gøgsig obtained new results in his thesis that will help to improve the outcome of catalytic processes and improve their scope. The results will thus become key references for tomorrow's new applications. All chapters include insightful discussions and in-depth descriptions of the key principles of these new discoveries.

Download or read book Novel Palladium Precatalysts and Their Application in Cross Coupling Reactions and Copper catalyzed Enantioselective Ring Formation written by Nicholas Charles Bruno and published by . This book was released on 2015 with total page 427 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chapters 1 - 3. A series of easily prepared, phosphine-ligated palladium precatalysts based on the 2-aminobiphenyl scaffold have been prepared. The role of the precatalyst-associated labile halide (or pseudohalide) in the formation and stability of the palladacycle has been examined. It was found that replacing the chloride in the previous version of the precatalyst with a mesylate leads to a new class of precatalysts with improved solution stability and that are readily prepared from a wider range of phosphine ligands, including the bulky, electron-rich di-tert-butylphosphino biaryl ligands. Additionally, N-methyl- and N-phenyl analogues have been prepared. These efficacy of these precatalysts were examined in a broad range of C-C, C-N, and C-O bond-forming reactions. Chapter 4. The intramolecular hydroalkylation of di- and trisubstituted alkenes bearing a pendant alkyl bromide to form stereodefined (hetero)carbocycles is reported. The system is highly regio- and stereoselective and employs a Cu-DTBM-SEGPHOS catalyst and (dimethoxy)methylsilane as the stoichiometric reductant. This intramolecular hydroalkylation reaction provides facile access to a multitude of ring systems and its utility is further demonstrated in the enantioselective synthesis of paroxetine.

Download or read book Metal Catalyzed Reactions in Water written by Pierre Dixneuf and published by John Wiley & Sons. This book was released on 2013-02-25 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water is abundant in nature, non-toxic, non-flammable and renewable and could therefore be safer and economical for the chemical industry wherever it is used as a solvent. This book provides a comprehensive overview of developments in the use of water as a solvent for metal catalysis, illustrating the enormous potential of water in developing new catalytic transformations for fi ne chemicals and molecular materials synthesis. A group of international experts cover the most important metalcatalyzed reactions in water and bring together cutting-edge results from recent literature with the first-hand knowledge gained by the chapter authors. This is a must-have book for scientists in academia and industry involved in the fi eld of catalysis, greener organic synthetic methods, water soluble ligands and catalyst design, as well as for teachers and students interested in innovative and sustainable chemistry.

Download or read book Applications of Transition Metal Catalysis in Drug Discovery and Development written by Matthew L. Crawley and published by John Wiley & Sons. This book was released on 2012-05-14 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the drug discovery and development applications of transition metal catalyzed processes, which can efficiently create preclinical and clinical drug candidates as well as marketed drugs. The authors pay particular attention to the challenges of transitioning academically-developed reactions into scalable industrial processes. Additionally, the book lays the groundwork for how continued development of transition metal catalyzed processes can deliver new drug candidates. This work provides a unique perspective on the applications of transition metal catalysis in drug discovery and development – it is a guide, a historical prospective, a practical compendium, and a source of future direction for the field.