Download or read book Part I Preparation and Application of Polymer supported Catalysts written by Biau-Hung Chang and published by . This book was released on 1979 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polymer Supported Organic Catalysts written by Narendra Chauhan and published by CRC Press. This book was released on 2024-07-26 with total page 247 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymer-supported organic catalysts are largely insoluble in most reaction solvents, which allows for easy recovery and recycling of the catalysts. They are generally stable, readily available, and environmental friendly, so they have attracted the interest of many synthetic chemists in the industrial and academic fields. In this book, different types of polymer-supported catalysts based on peptides, polystyrene, polyethers, poly(acrylic acid), poly(ethylene imine), poly(2-oxazoline), poly(isobutylene), poly(norbornene), etc., as well as metals are included with their synthetic organic synthesis applications. It is believed that this work will be of interest to organic chemists, material scientists, chemical engineers, polymer scientists and technologists.
Download or read book Polymer Supported Chemical Reactions written by P. Hodge and published by iSmithers Rapra Publishing. This book was released on 1991 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymer supported chemical reactions may include those using supported substrates, reagents and catalysts, and this report describes all three types. In all cases the most frequent reason for the use of a polymeric support will be the ease of separation of the supported and the low molecular c099 species. An additional indexed section containing several hundred abstracts from the Rapra Polymer Library database provides useful references for further reading.
Download or read book Catalyst Preparation written by John Regalbuto and published by CRC Press. This book was released on 2016-04-19 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt: This text explores the optimization of catalytic materials through traditional and novel methods of catalyst preparation, characterization, and monitoring for oxides, supported metals, zeolites, and heteropolyacids. It focuses on the synthesis of bulk materials and of heterogeneous materials, particularly at the nanoscale. The final chapters examine pretreatment, drying, finishing effects, and future applications involving catalyst preparation and the technological advances necessary for continued progress. Topics also include heat and mass transfer limitations, computation methods for predicting properties, and catalyst monitoring on laboratory and industrial scales.
Download or read book Preparation of Catalysts VII written by R. Maggi and published by Elsevier. This book was released on 1998-08-17 with total page 1007 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proceedings of the VIIth International Symposium on the Scientific Bases for the Preparation of Heterogeneous Catalysts, are in line with the general scope of this series of events. Emphasis in all Symposia has been on the scientific aspects of the preparation of new and industrial catalysts, or on new methods of preparation, rather than on the catalytic reactions in which such solids are ultimately used. In the present context, the catalytic event itself has only been considered as another, though often decisive, method of catalyst characterization.
Download or read book Supported Catalysts from Polymers to Gold Nanoparticles Supports written by William J. Sommer and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In today's world, the need to limit the use of nonrenewable resources and the importance of recycling has been recognized. One important contribution of chemists toward the general goal of limiting their use is to find catalysts that can be reused and recycled thereby limiting the need for expensive metal precursors and metal waste. Strategies to recycle catalysts are multifold and range from the employment of soluble polymers as catalyst supports to the use of membrane-encapsulated catalyst. The use of soluble polymers as a support not only offers the advantage of being soluble under the catalytic reaction conditions but also, to be removable by changing the conditions of the surrounding media. Despite the great potential of these soluble supported catalysts, their use is very limited in today's synthesis. In addition, no set of rules have been established to guide the synthesis of efficient supported catalysts. In order to establish a "tool box" for the synthesis of supported catalysts, the study of several parameters such as the choice of the support and the choice and the stability of the catalyst are necessary. To establish this set of rules, a limited number of catalytic transformations, were studied. These catalytic reactions are the Heck-Mizoroki, Suzuki-Miyaura and Sonogashira coupling reactions. These transformations became fundamental for the synthesis of drugs and materials. The first and second chapters provide background information by describing and evaluating the main supports that were previously used for catalysts and the two main catalysts that are used in this thesis, the palladium pincer complex and the palladium N-heterocyclic complex. In chapter 3, the synthesis of a soluble polymer supported catalyst is described. The polymer chosen for the study is poly(norbornene), and the catalyst is a 1,3-disubstituted benzene ligand with sulfurs in the side-chains able to chelate to the metal center, better known as pincer ligand. These ligands are abbreviated by the three atoms that coordinate to the metal center, in this study, SCS. The metal used for the investigation of the activity of this supported pincer is palladium. The importance of the nature of the linkage on the stability of the Pd-SCS pincer complex has been reported in the literature, leading to the synthesis of Pd-SCS pincer complex tethered to the polymer via an ether and an amide linkage. The synthesized poly(norbornene) supported Pd-SCS pincer complexes were evaluated using the Heck transformation of iodobenzene with n-butyl acrylate. Kinetic studies and leaching tests using poly(vinyl pyridine) and mercury were carried out resulting in the conclusion that the active species during the catalysis is not the palladium pincer complex but a leached palladium (0) species. In chapter 4, Pd-PCP pincer complexes with the ether and amide tether were synthesized. Kinetic and poisoning studies were carried out resulting in a similar conclusion. Furthermore, 31P NMR experiments were conducted to investigate the unstability of the complex. Following this study, in-situ XAS as well as computational calculations were carried out. The conclusion from this investigation argues that triethylamine is a key ingredient for the decomposition of the Pd-PCP complex. The overall conclusion from these two different studies is thta Pd(II) pincer complexes decomposes during the Heck reaction when triethylamine is used for the coupling of iodobenzene to n-butyl acrylate in DMF at 120°C. Stemming from this investigation, a reported more stable complex, Pd-NHC, was tethered onto poly(norbornene). The system was evaluated using Suzuki-Miyaura, Heck and Sonogashira reactions. Similar poisoning and kinetic studies were utilized to investigate the stability of the supported NHC Pd complexes. The result of this investigation suggests that supported Pd-NHC complexes are stable under Suzuki-Miyaura and Sonogashira but decompose under Heck conditions. However, when the system was recycled, a decrease in activity for the Suzuki-Miyaura transformation and solubility was observed. In chapter 6, gold monolayer protected clusters (MPC) were investigated as potential candidates as supports. To examine the potential of MPC as a support, a NHC-Pd complex was graphted onto the particles. To functionalize the gold nanoparticles, a new method was developed. Using azide moieties added to the gold nanoparticles, the catalyst was added via microwave assisted 1,3 dipolar cycloaddition. The system was evaluated using Suzuki-Miyaura transformations under microwave conditions. The system exhibited quantitative conversions for a variety of substrates. However, when the system was recycled, aggregation of the particles and decrease in catalytic activity was observed. In summary, this thesis describes the synthesis and evaluation of poly(norbornene) supported Pd-pincer and Pd-NHC complexes and of gold nanoparticles supported Pd-NHC complex. It also detail the combination of kinetic and poisoning studies developed to evaluate a potential supported catalyst.
Download or read book Polymers as Aids in Organic Chemistry written by N.K Mather and published by Elsevier. This book was released on 2012-12-02 with total page 271 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymers as Aids in Organic Chemistry covers the broad classifications and application of polymers in organic chemistry. This book is organized into 15 chapters that focus on the transformation of polymers and their role in other reagents that must be easily separated from their final product. After a brief introduction to polymer chemistry, the book presents a tabulation of the various types of polymers that have been used and the methods for their characterization. It then discusses the use of polymers as supports in peptide, oligonucleotide, and oligosaccharide chemistry; in peptide sequencing; in monofunctionalized difunctional compounds preparation, as aids in asymmetric syntheses; and as trapping agents in the determination of reaction intermediates. The subsequent chapters describe the use of polymers as catalysts, with particular emphasis on transition metals immobilized in the polymer matrix and used as catalysts. The concluding chapters examine polymer-immobilized compounds, enzymes, and whole cells that have been used to carry out a large number of reaction, most of which impinge on the area of organic chemistry. Polymer scientists and researchers and organic chemists will find this book invaluable.
Download or read book Polymeric Chiral Catalyst Design and Chiral Polymer Synthesis written by Shinichi Itsuno and published by John Wiley & Sons. This book was released on 2011-06-28 with total page 674 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reviews chiral polymer synthesis and its application to asymmetric catalysis. It features the design and use of polymer-immobilized catalysts and methods for their design and synthesis. Chapters cover peptide-catalyzed and enantioselective synthesis, optically-active polymers, and continuous flow processes. It collects recent advances in an important field of polymer and organic chemistry, with leading researchers explaining applications in academic and industry R & D.
Download or read book Catalytic Methods in Asymmetric Synthesis written by Michelangelo Gruttadauria and published by John Wiley & Sons. This book was released on 2011-09-27 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers advances in the methods of catalytic asymmetric synthesis and their applications. Coverage moves from new materials and technologies to homogeneous metal-free catalysts and homogeneous metal catalysts. The applications of several methodologies for the synthesis of biologically active molecules are discussed. Part I addresses recent advances in new materials and technologies such as supported catalysts, supports, self-supported catalysts, chiral ionic liquids, supercritical fluids, flow reactors and microwaves related to asymmetric catalysis. Part II covers advances and milestones in organocatalytic, enzymatic and metal-based mediated asymmetric synthesis, including applications for the synthesis of biologically active molecules. Written by leading international experts, this book consists of 16 chapters with 2000 References and illustrations of 560 schemes and figures.
Download or read book Synthesis of Polymer Supported Catalysts and NHC Metal Complexes for Organo and Organometallic Catalysis written by Gajanan Manohar Pawar and published by . This book was released on 2010 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polymeric Reagents and Catalysts written by Warren T. Ford and published by . This book was released on 1986 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Examines recent advances in the use of polymeric reagents and catalysts with a special emphasis on new compounds, synthetic methods, and industrial processes. Brings these advances to the attention of those who are involved in organic synthesis and desire a more thorough understanding of polymers and polymeric reagents. Contains comprehensive chapters devoted to polymeric oxidizing agents, Wittig reagents, and synthesis of cross-linked polymeric templates for chiral recognition. Presents opportunities for invention and use of many new polymeric reagents and catalysts.
Download or read book Supported Catalysts and Their Applications written by David C Sherrington and published by Royal Society of Chemistry. This book was released on 2007-10-31 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: The need to improve both the efficiency and environmental acceptability of industrial processes is driving the development of heterogeneous catalysts across the chemical industry, including commodity, specialty and fine chemicals and in pharmaceuticals and agrochemicals. Drawing on international research, Supported Catalysts and their Applications discusses aspects of the design, synthesis and application of solid supported reagents and catalysts, including supported reagents for multi-step organic synthesis; selectivity in oxidation catalysis; mesoporous molecular sieve catalysts; and the use of Zeolite Beta in organic reactions. In addition, the two discrete areas of heterogeneous catalysis (inorganic oxide materials and polymer-based catalysts) that were developing in parallel are now shown to be converging, which will be of great benefit to the whole field. Providing a snapshot of the state-of-the-art in this fast-moving field, this book will be welcomed by industrialists and researchers, particularly in the agrochemicals and pharmaceuticals industries.
Download or read book Synthesis and Application of New Polymer Bound Catalysts written by Brandon Michael Fetterly and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitric acid has been shown to be a weak acid in acetonitrile. It is conceivable that a nitrate salt of a weakly Lewis acidic cation could furnish a ''naked'' nitrate anion as a basic catalyst in a variety of reactions in non-aqueous solvents. Such a nitrate salt could also be bound to a polymeric support via the cation, thereby allowing for reclamation and recycling of the nitrate ion. This subject is dealt with in Chapter 2, wherein my contributions consisted of performing all the reactions with the polymer supported catalyst and carrying out the experiments necessary to shed light on the reaction mechanisms. Chapter 3 contains a description of the structure and catalytic properties of an azidoproazaphosphatrane. This compound is an air-stable versatile catalyst that has proven useful not only homogeneously, but also when bound to a solid support. The synthesis of a polymer bound proazaphosphatrane containing a trivalent phosphorus is presented in Chapter 4. Such a compound has been sought after by our group for a number of years. Not only does the synthesis I have accomplished for it allow for easier separation of proazaphosphatrane catalysts from reaction mixtures, but recycling of the base is made much simpler. Proazaphosphatranes are useful homogeneous catalysts that activate atoms in other reagents, thus enhancing their reactivity. The next chapters deal with two such reactions with aldehydes and ketones, namely silylcyanations with trialkylsilylcyanides (Chapters 5 and 6) and reductions with poly(methylhydrosiloxane), in Chapter 7. In Chapter 5, Zhigang Wang performed the initial optimization and scoping of the reaction, while repetitions of the scoping experiments for reproducibility, determination of diastereomeric ratios, and experiments aimed at elucidating aspects of the mechanism were performed by me. The proazaphosphatrane coordinates to the silicon atom in both cases, thereby allowing the aforementioned reactions to proceed under much milder conditions. Proazaphosphatranes are also effective Broensted-Lowry bases. This is illustrated in Chapter 8 wherein a wide variety of conjugate addition reactions are catalyzed by proazaphosphatranes. In that chapter, repetitions of the nitroalkane addition reactions for reproducibility, improved spectral data for the products and comparisons of literature yields of all reactions were performed by the author.
Download or read book Handbook of Transition Metal Polymerization Catalysts written by Ray Hoff and published by John Wiley & Sons. This book was released on 2010-09-16 with total page 599 pages. Available in PDF, EPUB and Kindle. Book excerpt: A one-stop resource for understanding and applying polymerization catalysts An edited volume featuring contributions from leading researchers, the Handbook of Transition Metal Polymerization Catalysts covers the design and synthesis of catalysts, and their applications in synthesis of polymers. Dealing with those polymerization catalysts that afford commercially acceptable yields of polymer with respect to catalyst mass and promising newer catalysts, this practical reference provides polymer and organic chemists with a comprehensive overview of the known methods for developing and applying these important catalysts. With both recent advances and historically important catalysts, the subjects covered in this text include: Metal alkyls and other compounds that function as co-catalysts with a large number of catalysts The varieties of porous silica either necessary or valuable in certain catalyst formulations Catalyst scale-up and commercialization Copper catalysts for olefin polymerization Morphology control Along with the above topics, the Handbook of Transition Metal Polymerization Catalysts provides tables of valuable data to assist in reproducing a synthesis or applying the knowledge to a new problem. Polymerization reactivities, polymer properties, monomer and solvent purity requirements, molecular weights, distribution, and reactivity ratios are also covered. The Handbook of Transition Metal Polymerization Catalysts offers an excellent one-stop resource for understanding and applying polymerization catalysts.
Download or read book Polymer supported Catalysts for Greener Synthesis written by Thanh Son Nam Phan and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis of Polymer supported Reducing Reagents and the Study of Their Catalytic Properties written by Hsueh-Chi Lee and published by . This book was released on 1979 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis and Immobilization of Catalysts on Polymer Supports and Its Application in Chemo and Enantioselective Oxidation Reactions written by Tamilselvi Chinnusamy and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
