![]() |
Welcome to Loot.co.za!
Sign in / Register |Wishlists & Gift Vouchers |Help | Advanced search
|
Your cart is empty |
||
|
Books > Science & Mathematics > Chemistry > Physical chemistry > Catalysis
Since the first application of dendrimers in catalysis in the mid 1990s, this field has advanced rapidly. As a consequence, catalytically active dendrimers have emerged as a class of molecular catalysts that has substantially enriched the field of homogeneous (and in part heterogeneous) catalysis. A general survey of transition metal dendrimer catalysts and the way they have developed is followed by in-depth discussions of dendritic transition metal catalysis based on non-covalent catalyst-support interaction and an overview of the rapidly growing field of stereoselective dendrimer catalysis. The development of dendrimer-encapsulated bimetallic nanoparticles has provided the interface with heterogeneous colloid catalysis. As cheaper and readily accessible alternatives to regular dendrimers, hyperbranched polymers are increasingly being used as catalyst platforms. These topics are complemented by a review of metallodendritic exoreptors for the redox recognition of oxo-anions and halides.
Palladium is a remarkable metal. In particular, organopalladium chemistry has made remarkable progress over the last 30 years. That progress is still continuing, without any end in sight. This book presents a number of accounts and reviews on the novel Pd-catalyzed reactions discovered mainly in the last five years. The book covers Pd-catalyzed reactions that are new entirely different from the more standard ones. Topics such as new reactions involving ss-carbon elimination and formation of palladacycles as key reactions, cross-coupling of unactivated alkyl electrophiles with organometallic compounds, arylation via C-H bond cleavage, Pd/norbornene-catalyzed aromatic functionalizations, three-component cyclizations of allenes, use of N-heterocyclic carbenes as ligands, asymmetric reactions catalyzed by Pd(II) compounds such as Lewis acids, cycloadditions of arynes and alkynes, and nucleophilic attack by Pd species are surveyed in detail by researchers who have made important contributions to these fields. The book addresses graduate students majoring in organic synthesis and researchers in academic and industrial institutes."
Bioorganometallic Chemistry has become a mature area of science and is comprehensively covered by leading experts in this book. Naturally occuring bioorganometallic complexes, such as vitamin B12 and recently discovered iron and nickel hydrogenases, including a possible role of the latter in the geochemical theory of the origin of life, are considered. The possible formation of carbene complexes of cytochrome P450 enzymes in various metabolisms of xenobiotics is also discussed. The bioorganometallic chemistry is considered to provide not only organometallic receptors such as polynuclear organometallic macrocycles for biologically interesting molecules but also ferrocene-peptide bioconjugates giving a peptidomimetic basis for protein folding. The medicinal properties of organometallic compounds are reviewed, with notable applications in the treatment and diagnosis of cancer and in the treatment of viral, fungal, bacterial and parasitic infections. Therefore the reader will get a balanced view of this rapidly developing and promising area.
Carbonylation reactions are of major importance in both organic
and industrial chemistry. Due to the availability, price and
reactivity pattern, carbon monoxide is becoming a more and more
important building block for fine and bulk chemicals. The major
reaction types of carbon monoxide are comprehensively discussed by
leading experts from academia and industry. The authors highlight
important carbonylation reactions such as hydroformylation,
alkoxy-carbonylations, co/olefin-copolymerization, Pauson-Khand
reactions and others. They illustrate applications in organic
synthesis and give industrial examples.
Biological nitrogen fixation provides more than 50% of the total annual input of the essential element nitrogen to world agriculture. Thus, it is of immense agronomic importance and critical to food supplies, particularly in developing countries. This book, with chapters authored by internationally renowned experts, provides a comprehensive and detailed account of the fascinating history of the process - including the surprising discoveries of molybdenum-independent nitrogenases and superoxide-dependent nitrogenase; a review of Man's attempts to emulate the biological process - most successfully with the commercially dominant Haber-Bosch process; and the current state of the understanding art with respect to the enzymes - called nitrogenases - responsible for biological nitrogen fixation. The initial chapters use a historical approach to the biological and industrial processes, followed by an overview of assay methodologies. The next set of chapters focuses on the classical enzyme, the molybdenum nitrogenase, and details its biosynthesis, structure, composition, and mechanism of action as well as detailing both how variants of its two component proteins are constructed by recombinant DNA technology and how computational techniques are being applied. The sophisticated chemical modelling of the metal-containing clusters in the enzyme is reviewed next, followed by a description of the two molybdenum-independent nitrogenases - first, the vanadium-containing enzyme and then the iron-only nitrogenase - together with some thoughts as to why they exist Then follows an up-to-date treatment of the clearly "non-classical" properties of the superoxide-dependent nitrogenase, which more closely resembles molybdenum-containing hydroxylases and related enzymes, like nitrate reductase, that it does the other nitrogenases. Each chapter contains an extensive list of references. This book is the self-contained first volume of a comprehensive seven-volume series. No other available work provides the up-to-date and in-depth coverage of this series and this volume. This book is intended to serve as an indispensable reference work for all scientists working in this area, including agriculture and the closely related metals-in-biology area; to assist students to enter this challenging area of research; and to provide science administrators easy access to vital relevant information.
1. Introduction. There is much interest in the general subject of porous inorganic materials with respect to their use as sorbents or catalysts. Such inorganic solids may be microporous, mesoporous or macroporous according to the sizes of the pores within the solid. Often there is a range of pore sizes within any given solid and so there is special interest in the synthesis, characterisation and application of porous inorganic solids with well defined pores. Pores of diameter larger than 50 nm are generally termed macropores. Those with diameters of less than 2 nm are micropores and pores of intermediate size are called mesopores. Solids, which contain only mesopores, are correctly called mesoporous but very often there is a combination of different types of porosities within one given solid. The synthesis, characterisation and application of microporous solids is much more advanced than is the case with mesoporous substances. Moreover, the synthesis of crystalline mesoporous materials is one clear goal for the future but which has not been attained so far. Consequently, it is of interest to examine the current state of our knowledge of microporous materials and to examine how this may apply to mesoporous materials. Both catalytic and sorption processes could benefit from studies of mesoporous solids because the mesopores could permit diffusion of larger reactants or products than is the case in microporous materials. 2.
Computational Modelling of Homogeneous Catalysis is an extensive collection of recent results on a wide array of catalytic processes. The chapters are, in most cases, authored by the researchers who have performed the calculations. The book illustrates the importance of computational modelling in homogeneous catalysis by providing up-to-date reviews of its application to a variety of reactions of industrial interest, including: -olefin polymerization; This book facilitates understanding by experimental chemists in the field on what has already been accomplished and what can be expected from calculations in the near future. In addition, the book provides computational chemists with a first-hand knowledge on the state of the art in this exciting field.
Polyolefin is a major industry that is important for our economy and impacts every aspect of our lives. The discovery of new transition metal-based catalysts is one of the driving forces for the further advancement of this field. Whereas the classical heterogeneous Ziegler-Natta catalysts and homogeneous early transition metal metallocene catalysts remain the workhorses of the polyolefin industry, in roughly the last decade, tremendous progress has been made in developing non-metallocene-based olefin polymerization catalysts. Particularly, the discovery of late transition metal-based olefin polymerization catalysts heralds a new era for this field. These late transition metal complexes not only exhibit high activities rivaling their early metal counterparts, but more importantly they offer unique properties for polymer architectural control and copolymerization with polar olefins. In this book, the most recent major breakthroughs in the development of new olefin polymerization catalysts, including early metal metallocene and non-metallocene complexes and late transition metal complexes, are discussed by leading experts. The authors highlight the most important discoveries in catalysts and their applications in designing new polyolefin-based functional materials.
"Metal Catalysed Reactions in Ionic Liquids" is the first
non-edited book on the subject of metal catalyzed reactions in
ionic liquids to cover the literature from its origins until early
2005.
"Multi-scale Quantum Models for Biocatalysis" explores various molecular modelling techniques and their applications in providing an understanding of the detailed mechanisms at play during biocatalysis in enzyme and ribozyme systems. These areas are reviewed by an international team of experts in theoretical, computational chemistry, and biophysics. This book presents detailed reviews concerning the development of various techniques, including ab initio molecular dynamics, density functional theory, combined QM/MM methods, solvation models, force field methods, and free-energy estimation techniques, as well as successful applications of multi-scale methods in the biocatalysis systems including several protein enzymes and ribozymes. This book is an excellent source of information for research professionals involved in computational chemistry and physics, material science, nanotechnology, rational drug design and molecular biology and for students exposed to these research areas.
New Trends in Enzyme Catalysis and Biomimetic Chemical Reactions embraces modern areas of enzyme catalysis where other books in the field concentrate mainly on kinetic, bioorganic and biochemical aspects of the enzyme catalysis and do not cover biophysical and physicochemical problems. Topics covered include: -modern physical and kinetic methods of investigation,
Some years ago, I agreed to contribute a volume to the Academic Press 'Organo metallic Chemistry' series - the metals to be covered were rhodium and iridium. Initially, my plan was to discuss both the fundamental organometallic chemistry and applications in organic synthesis. When the first draft of the manuscript was complete, it was apparent that I had exceeded my allowance of pages by a huge amount. It was then that I decided that the catalysis section warranted separate treatment. I am grateful to Reidel for agreeing to publish this volume on Homogeneous Catalysis with Compounds of Rhodium and Iridium as part of their 'Catalysis by Metal Complexes' series. The material I had for the original Academic Press project covered the litera ture to the end of 1978. I decided to update this to the end of 1982 with a few key references from 1983. It is some measure of the rate of progress in this field that the number of references almost doubled during this revision."
In recent years, the liquid phase oxidation of organic substrates using transition metal compounds as catalysts has become a profitable means of obtaining industrially important chemicals. Millions of tons of valuable petrochemicals are produced in this manner annually [1]. Typical examples of such processes are the production of vinyl acetate or acetaldehyde via the Wacker process, equations (1) and (2); the Mid Century process for the oxidation of methyl aromatics, such as p-xylene to tereph thalic acid, equation (3); and the production of propylene oxide from propylene using alkyl hydroperoxides, equation (4). PdCI , CuCI 2 2 (1) CH2 = CH2 + 1/2 O2 -H 0 ~ CH3CHO 2 (2) Co(OAcjz ~ (3) (4) The vast majority of liquid phase transition metal catalyzed oxidations of organic compounds fall into these three broad categories: (a) free radical autoxidation reactions, (b) reactions involving nucleophilic attack on coordinated substrate such as the Wacker process, or (c) metal catalyzed reactions of organic substrates with hydroperoxides. Of these three classes of oxidations only the first represents the actual interaction of dioxygen with an organic substrate. The function of oxygen in the Wacker process is simply to re-oxidize the catalyst after each cycle [2].
Soluble catalysts are used extensively in many branches of chemistry and are indeed a vital constituent of many natural processes. They find wide application throughout the chemical industry where they assist in the production of several million tonnes of chemicals each year. Since homogeneous systems, especially those incorporating transition metals, often function effectively under milder conditions than their heterogeneous counterparts, they are becoming increasingly important at a time when the chemical industry in particular, and society in general, is seeking ways of conserving energy and of making the best possible use of available resources. My principal objective in- writing this book is to engender sufficient enthusiasm for, and knowledge of, the subject in the reader that he or she will be encouraged to begin, or continue, to make their own contribution to advancing our knowledge of homogeneous catalysis. After attempting to acquaint the reader with some of the ground rules I have tried to describe the present scope, and the future potential, of this fascinating field of chemistry by drawing both on academic and on industrial data sources. This approach stems from a personal conviction that future progress could be considerably hastened by a more meaningful dialogue between chemists working both in industrial and in academic research institutions. Wherever possible, examples of the commercial application of homogeneous catalyst systems have been included and no attempt has been made in any way to disguise the many unresolved questions and exciting challenges which still pervade this rapidly developing area.
The field of petrochemicals started some years ago with the simple addition reaction of water to propylene for the production of isopropyl alcohol. Currently, the petrochemical industry has become a multi-billion dollar enterprise which encompasses a wide field of chemical products. Almost all the basic organic reactions such as hydrogenation, alkylation, substitution, polymerization, etc. are utilized for the production of these chemicals. It may not, however, have been possible to establish this huge industry without the use of different catalysts. In other words, the great advancements in the catalytic area have supported the vast developments in the petrochemical field. In this book, we have adopted the idea of discussing the petrochemical industry from the point of view of reactants' activities and susceptibilities toward different catalysts. The book is thus classified according to the reaction type. This will eriable students and other users of the book to base their understanding of the petrochemical field on the fundamental principles learned in chemistry. How ever, the first chapter is aimed at establishing some basic facts on the petro chemical industry and its major uses. It discusses, without going into details, the raw materials used, the intermediates and the downstream products. The next eight chapters discuss in some detail the main reactions and the catalysts used for the production of chemicals and polymers from petroleum. The last chapter is devoted to a discussion of some of the practical techniques used in the catalytic field."
This volume contains the lectures presented at the Advanced Study Institute on "Chemistry and Chemical Engineering of Catalytic Solid Fuel Conversion for the Production of aean Synthetic Fuels" which was held at Ak;ay, Edremit, Tiirkiye, between July 21 and August 3, 1991. The book includes 23 chapters originally written for the meeting by distinguished scientists an technologists in the field. l would like to acknowledge the contribution of each of the authors in the book. Their efforts have shed light on our understanding in coal science research and better utilization of coal. Three main subjects: structure and reactivity of coal; cleaning of coal and its products, and factors affecting environmental balance of energy usage and solutions for future, were discussed in the Institute and these are presented under six groups in the book. I hope that of great use to research workers from academic and industrial background. the book will be Many people contributed to the success of the Institute on which this volume was based. I take this occasion to thank my colleagues who lectured in the Institute, both for their efforts during the two weeks and their expertly prepared lecture notes that reached to me in time. The Institute was generously sponsored by the Scientific and Environmental Affairs Dh.ision of the NATO and their contribution is deeply acknowledged."
Light alkanes tend to be resistant to many forms of activation. The horizontal approach of the present book covers homogeneous, heterogeneous and biological catalysis, thus allowing readers to gain an awareness of progress and ideas in research areas different from their own. The book contains both general chapters, giving an overview of the subject, and specialised contributions that deal with the details and state of the art. A specialist report is also included which gives a critical insight into current progress and discusses future prospects and major challenges. Audience: Newcomers and senior researchers in the field of alkane activation. The mixed theoretical and practical approach will be of interest to researchers and industrialists alike.
Hydrogen peroxide is a chemical that is becoming increasingly fashionable as an oxidant, both in industry and in academia and whose production is expected to increase significantly in the next few years. This growth in interest is largely due to environmental considerations related to the clean nature of hydrogen peroxide as an oxidant, its by-product being only water. To date this chemical has largely been employed as a non-selective oxidant in operations like the bleaching of paper, cellulose and textiles, or in the formulation of detergents, and only to a minimal extent in the manufacture of organic chemicals. This book has been organized to cover the different aspects of the chemistry of hydrogen peroxide. The various chapters into which the book is divided have been written critically by the authors with the general aim of stimulating new ideas and emphasizing those aspects that are likely to lead to new developments in organic synthesis in the coming future.
Directed metalation is recognized as one of the most useful methodologies for the regio- and stereoselective generation of organometallic species, the generation of which necessarily leads to the selective formation of organic products. Cyclometalation using Li, Mn, and Pd, and directed hydrometalation and carbometalation using Al and Zn, have been utilized for regio- and/or stereoselective synthesis for decades. Recently, a new chelation-assisted methodology has been developed not only for controlling regio- and stereoselectivity of reactions, but also for accelerating reactions. In particular, chelation-methodology has been utilized as a new activation method, in which a carbon-metal bond is generated directly from a C-H bond; a reaction rarely achieved using conventional methods. A wide variety of catalytic functionalization reactions of C-H bonds by the utilization of a chelation, have been developed recently and are comprehensively discussed in this book by leading experts. In addition, new approaches to directed hydrometalation and directed carbometalation as a key step are also discussed. A unique stereo- and regioselective hydroformylation has been developed through the utilization of directed hydrometalation. The regioselective Mizoroki-Heck reaction is another example in which directed carbometalation can be used to achieve a high regioselectivity. These examples emphasize how these innovative methodologies are contributing to different fields of chemistry.
The use of phosphine derivatives has historically induced the tremendous development of catalysis (both non-asymmetric and asymmetric). Although the chemistry of amines is more documented, the use of nitrogen-containing ligands only appeared recently. Nevertheless, during the last ten years, the results describing chiral diamine preparations and their uses in asymmetric catalysis and synthesis are increasing faster than their phosphorus counterparts. The reader will find in this volume the most recent methods for the synthesis of chiral diamines as well as their applications in asymmetric catalysis of CC bond formation. Particular attention will be given to spartein and derivatives of such diamines. Recently, the particular properties and the chemistry of amines allowed to obtain catalysts easy to separate and recycle and new types of ligands such as diaminocarbenes, ureas and thioureas. Finally, the complexing properties of some diamines allowed the formation of complexes with chirality "at the metal " which is of major theoretical interest and presents numerous potential applications.
3.1.1 ?-Conjugated Materials ?-conjugated polymers (CPs) and oligomers are materials with an extended ?-system along the backbone. The materials possess many remarkable prop- ties, including high charge carrier mobilities, electrical conductivities (doped), electrochromism, and electroluminescence [1]. These properties have been taken advantage of in exploration of potential applications including in ch- ical sensors, light-emitting devices, and ?eld-effect transistors. Many efforts have been devoted to synthesizing new conjugated polymers and oligomers in an effort to increase their processibility, optimize the desirable properties, and explore new properties. In Fig. 3.1 are shown examples of some of the CPs that have been prepared and studied. Coupling ?-conjugated materials to metal complexes gives hybrid mate- als in which the properties of the metal complex may be coupled to those of the conjugated backbone [2]. For example, these materials could be used in energy-harvesting devices such as solar cells or polymer-based light-emitting devices,wherehighchargecarrier mobilities of theconjugatedmaterialmay be combined with either the light-absorbing or emitting metal groups, giving improved device performance [3, 4]. In addition to an electronic role, metal complexes may also be used to geometrically orient ?-conjugated materials in speci?c three-dimensional arrangments in the solid state. Careful conside- tion of theelectronicinteractionsand excitedstatesisnecessary for thedesign of functional materials of this type.
Hydrotreating catalysis with transition metal sulphides is one of the most important areas of industrial heterogeneous catalysis. The present book deals with the chemical and catalytic aspects of transition metal sulphides, focusing on their use in hydrotreating catalysis. The book?'s 12 chapters present reviews of solid-state, coordination and organometallic chemistry, surface science and spectroscopic studies, quantum chemical calculations, catalytic studies with model and real catalysts, as well as refinery processes. A presentation of state-of-the-art background to pertinent work in the field. Can be used as an introduction to the chemical and catalytic properties of transition metal sulphides as well as an advanced level reference.
Photosensitization and photocatalysis refer to processes by which permanent chemical transformations are induced on substrates (organic/inorganic) by radiation to which the substrates themselves are transparent. Such transformations can be highly specific, very efficient, and occur under mild conditions. Herein lies the power of photochemical methods for possible applications in the field of conversion and storage of solar energy. This book provides a recent survey of the progress in this important area in catalysis, with an emphasis on inorganic complexes and organometallic compounds as the key light aborbers. The book is organized in three parts: fundamentals, followed by applications. Discussions cover a wide variety of photosensitized or photocatalyzed reactions: decomposition of water, reduction of CO2 and CO; spectral sensitization in photoelectrochemical cells; transformations (oxidation, reduction, isomerization, hydrogenation, dehydrogenation, carbonylation, etc.) of organics such as alkanes, alkenes, alcohols, etc. In view of the variety of systems (sensitizers, substrates) and the topics covered, the volume is unique in the field of photochemistry and will appeal to academic and industrial researchers in various subdisciplines of chemistry, material science and catalysis.
Eighty per cent of all compounds produced in the chemical and pharmaceutical industries require at least one essential catalytic step during their synthesis. At the same time the use of hydrocarbons as a feed-stock for commodity and fine chemicals typically requires an oxidation step, which is usually mediated by a transition metal compound. Consequently oxidation catalysis is a major research field in chemistry, both in academia and in industry. In many such processes, species with metal-carbon bonds are formed as key intermediates, and these processes represent the primary focus of this volume. An important aspect covered by some of the expert contributors is the use of organic ligands - and thus organometallic complex metal fragments - to achieve efficient oxidation catalysis. It has not been self-evident that organometallic complexes can survive the conditions necessary for polar oxygen-transfer reactions, but research over the last decade concerning oxo and peroxo complexes functionalized by organic ligands has clearly shown that relatively non-polar M-C bonds can be quite stable in the presence of oxidants and protic media, and that they may even be essential for the favourable activity and life-time of a catalyst. Also considered in this context is the oxidation chemistry of basic organometallic species in the gas phase, as this may reveal fundamental characteristics inherent to oxidation catalysts.
This book highlights cyclization via carbopalladation and acylpalladation and Heck-pericyclic sequences. They discuss p-allyl palladium-based cascade reactions, Michael-type additions as an entry to transition-metal-promoted cyclizative transformations, and sequential or consecutive palladium-catalyzed processes, and show Pauson-Khand cascades, metal-catalyzed cyclizations of acyclic precursors, as well as cascade and sequential ruthenium-catalyzed transformations. This is a comprehensive overview of an exciting and highly dynamic, and innovative methodological concept. |
You may like...
Bounce Back! Years F-2 with eBook
Helen McGrath, Toni Noble
Digital product license key
R2,311
Discovery Miles 23 110
Behavioral Science in the Global Arena…
Elaine P. Congress, Harold Takooshian, …
Hardcover
R2,530
Discovery Miles 25 300
|