This book investigates the use of palladium modified by bulky ligands as catalysts for new chemical transformations that rapidly assemble several classes of complex heterocyles. It documents the development of new chemical reactions involving carbon-carbon (C-C) and carbon-halogen (C-X) bond formation in the context of alkene difunctionalization and dearomatization reactions. Due to the ubiquity of heterocycles in bioactive natural products and life-improving pharmaceutical treatments, a long-term goal for synthetic organic chemists has been to develop novel and creative heterocycle syntheses that illicit a high degree of product diversity and are characterized by mild reaction conditions and limited waste production. A considerable fraction of leading pharmaceutical drugs contain at least one heterocycle within their chemical structure, and their prevalence in these technologies is strong evidence that the fundamental curiosities of organic chemistry lead to real-world solutions for the health and wellness of the global population.

As nucleophiles, simple alkenes are typically so unreactive that only highly active electrophiles, such as carbocations, peroxides, and halogens will react with them. For the generation of carbon-carbon bonds, milder methods will often be required. Fortunately, it is possible to increase the reactivity of alkene-type p-nucleophiles by introducing electron-donating substituents. Substitution of one H with an OH or OR gives an enol or a vinyl ether, which are already much better nucleophiles. Using nitrogen instead of oxygen, one obtains even better nucleophiles, enamines. Enamines are among the most reactive neutral carbon nucleophiles, exhibiting rates that are even comparable to some charged nucleophiles, such as enolates [1, 2]. Most enamines, unfortunately, are sensitive to hydrolysis. The parent enamine, N,N-dimethylvinylamine, has in fact been prepared [3], but appears to be uns- ble. Enamines of cyclic ketones and many aldehydes can readily be isolated, however [4-7]. The instability of enamines might at first appear to diminish the utility of enamines as nucleophiles, but actually this property can be viewed as an added benefit: enamines can be readily and rapidly generated catalytically by using a suitable amine and a carbonyl compound. The condensation of aldehydes or ketones with amines initially affords an imine or iminium ion, which then rapidly loses a proton to afford the corresponding enamine (Scheme 1).

This outstanding thesis describes a detailed investigation into the use of low-oxidation-state group 14 complexes in catalysis, developed at the cutting edge of inorganic and organometallic chemistry. It includes the preparation of a number of landmark compounds, some of which challenge our current understanding of metal-metal bonding and low-oxidation-state main group chemistry. Among the many highlights of this thesis, the standout result is the development of the first well-defined, low- oxidation-state main group hydride systems as highly efficient catalysts in the hydroboration of carbonyl substrates, including carbon dioxide, which are as efficient as those observed in more traditional, transition-metal catalyses. These results essentially define a new subdiscipline of chemistry.

Surface organometallic chemistry is a new field bringing together researchers from organometallic, inorganic, and surface chemistry and catalysis. Topics ranging from reaction mechanisms to catalyst preparation are considered from a molecular basis, according to which the "active site" on a catalyst surface has a supra-molecular character. This. the first book on the subject, is the outcome of a NATO Workshop held in Le Rouret. France, in May. 1986. It is our hope that the following chapters and the concluding summary of recommendations for research may help to provide a definition of surface organometallic chemistry. Besides catalysis. the central theme of the Workshop, four main topics are considered: 1) Reactions of organometallics with surfaces of metal oxides, metals. and zeolites; 2) Molecular models of surfaces, metal oxides, and metals; 3) Molecular approaches to the mechanisms of surface reactions; 4) Synthesis and modification of zeolites and related microporous solids. Most surface organometallic chemistry has been carried out on amorphous high-surf ace-area metal oxides such as silica. alumina. magnesia, and titania. The first chapter. contributed by KNOZINGER. gives a short summary of the structure and reactivity of metal oxide surfaces. Most of our understanding of these surfaces is based on acid base and redox chemistry; this chemistry has developed from X-ray and spectroscopic data, and much has been inferred from the structures and reactivities of adsorbed organic probe molecules. There are major opportunities for extending this understanding by use of well-defined (single crystal) oxide surfaces and organometallic probe molecules."

Alexander L. Reznichenko and Kai C. Hultzsch: Catalytic ?-Bond Metathesis Zhichao Zhang, Dongmei Cui, Baoli Wang, Bo Liu, Yi Yang: Polymerization of 1,3-Conjugated Dienes with Lanthanide Precursors Frank T. Edelmann: Homogeneous Catalysis using Lanthanide Amidinates and Guanidinates Tianshu Li, Jelena Jenter, Peter W. Roesky: Rare Earth Metal Post-metallocene Catalysts with Chelating Amido Ligands

The present volume Uranium C5 covers the physical properties of U0 - the production 2 and preparation of U0 were already treated in Uranium C4, whereas the chemical proper 2 ties will be the subject of the forthcoming part C6. U0 is the most important chemical compound in all aspects of nuclear technology. 2 It is and will be for the foreseeable future the fuel for all light and heavy water reactors as well as (in the mixed crystal with Pu0 ) for the fast breeder reactors. Therefore, the 2 nuclear engineer has to understand the behavior of U0 under all conditions existing during 2 operational (and possibly failure) states of a nuclear reactor, e. g. , not only in the solid state but also to some extent in the liquid and gaseous states. Besides high scientific interest in the sometimes unique or unusual properties, e. g. , at low temperatures, a lot of data and physical properties which are critical for its use as a nuclear fuel have been determined more or less accurately. Creep, swelling, irradiation densification, and fission gas behavior in the fuel are properties which have been evaluated up to the high temperatu res (near the melting point) which may exist in U0 fuel due to its low thermal conductivity. 2 Besides these more technical data there have been accumulated a lot of important physical data, e. g.

Advances in Polymer Science enjoys a longstanding tradition and good reputation in its community. Each volume is dedicated to a current topic, and each review critically surveys one aspect of that topic, to place it within the context of the volume. The volumes typically summarize the significant developments of the last 5 to 10 years and discuss them critically, presenting selected examples, explaining and illustrating the important principles, and bringing together many important references of primary literature. On that basis, future research directions in the area can be discussed. Advances in Polymer Science volumes thus are important references for every polymer scientist, as well as for other scientists interested in polymer science - as an introduction to a neighboring field, or as a compilation of detailed information for the specialist.

Major portion of the planet earth is covered by seas and oceans representing 96.5% of the planet's water, playing a detrimental role in sustaining the plant including crop diversity and productivity for human consumption. Water resources contain both soluble and transition metals, which are easily absorbed by plants through roots as a first point of contact and subsequently play important physiological and biological functions in plants. Transition metals such as copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) contribute to the plant productivity by playing key functional roles in the photosynthesis. In addition, to their major role in regulating the plant productivity, they also play an important role by acting as homeostatic regulators in uni-parentally inherited chloroplasts and maintains the flow of the electron transfer. It is worthwhile to mention that they play a critical role as transporters, which acts as electron balancing units for managing the electrostatic potential across the membranes. In contrast, some metals such as Cd, As play a significant role in inducing the stress mechanism and influencing either directly or in-directly Haber-Weiss reactions either through the production of the reactive oxygen species (ROS) or through the membrane damage thus leading to leakage of membrane transporters. However, besides playing a detrimental role as transporters in plant system, excessive accumulation of these metals due to the increasing contamination in the marginal soil and water are posing important threats to the plant system. Realizing the toxic effects of the metals, several physiological evidences have been laid for the credence of the metal toxicity and their concurrent effect on plant productivity. Increasing effects of the metals as toxicants can have three adverse effects on the populations: population can move, persist via local adaptation or phenotypic plasticity, or die. Next generation sequencing studies have revolutionized our abilities to detect the changes in expression profiles across an array of genes, which can in-turn help to develop early markers of metal induced stress. Plant Metallomics and Functional Omics: A System-Wide Perspective focuses on the applications of the system wide understanding of the biological and functional interplay occurring at the juncture of the metalloid induced stress and toxicity. The main goal of this book is to familiarize the readers with the most up-to-date information on metal-induced physiological changes in plant species.

Embarking on a new millennium, the book in hands describes the recent developments of organsoselenium chemistry in all facets. Various distinguished scientists have contributed, with their skill and expertise, making this book a valuable source for synthetic oriented organic chemists and for those, who want to get a first insight into the chemistry of selenium.

The authors of this volume concentrate on the recent progress of novel polyoxometalate (POM) syntheses, as well as advances made in catalytic, electrochemical, and sensing systems. The state-of-the-art techniques such as flow system and gel-electrophoresis for the discovery of POMs are covered with a detailed discussion. Of particular importance, the application of POM-based materials in photo-sensing, heterogeneous catalysis, energy conservation and storage, and gas separation is reviewed. Over the past few years, POM chemistry has witnessed a remarkable progress with more than 1500 papers published each year. Due to their intrinsic structural features, POMs are considered as versatile building blocks for the construction of sophisticated complex assemblies and advanced multi-functional materials. Various strategies, methods, and techniques have been adopted to develop POM-based materials with intriguing properties and excellent performance. All the contributors to this volume are young, vibrant chemists in this research field and all the works are carefully collected from the authors' years of experience. This volume serves as an essential reference for every POM chemist and is of great interest to new researchers who wish to learn more about this area.

This completely revised and updated second edition of Organometallic Compounds in the Environment treats environmental organometallic chemistry as an integrated and coherent subject area in its own right, bringing together contributions from leading scientists throughout the world.

The Introduction summarizes and explores those properties of organometallic compounds that are relevant to their behaviour and impact in the natural environment. Subsequent chapters cover those elements whose organometallic derivatives are especially important in the environmental context. The natural formation of organometallics from inorganic precursors under environmental conditions is also treated in detail. An important underlying theme running through the work is the biological properties and toxicities of the organometallic species present in the environment. In general a full speciation approach is taken, where the full molecular identities of the compounds concerned are considered.

Research workers in the fields of organometallic compounds and their environmental impact, as well as those interested in organometallic and environmental chemistry generally, will welcome this new edition. It will also be invaluable as a source book to lecturers teaching courses at undergraduate or graduate level in applied, analytical, industrial, organometallic or environmental chemistry, or in environmental science in general.

This book is a comprehensive text covering the research and development trends in the booming field of transition metal catalyzed oxidative cross-coupling reactions. Oxidative cross-coupling reaction is a new method to forming chemical bonds besides the traditional cross-coupling reactions. This book provides the answers to how this coupling reaction occurs and what its advantages are. The palladium, copper and iron catalyzed oxidative cross-coupling reactions as the main focuses of interest are described in detail. The oxidative cross-coupling reactions catalyzed by other metals and transition-metal-free oxidative coupling reactions are also introduced.This book provides a useful reference source for researchers and graduates in the field of transition metal catalyzed coupling reactions. It is also valuable to researchers working in pharmaceutical companies, fine organic chemical companies, and etc.

Antoine Simonneau's thesis highlights the development of new cycloisomerization reactions through the activation of alkynes with gold complexes. First Simonneau describes 1,6-enynes and their direct conversion into allenes through 1,5-hydride or ester migration processes. The author and his team used appropriate propargylic functional groups to achieve this conversion. This study shows that O-tethered 1,6-enynes carrying a strained cycloalkane at the propargylic position could undergo a cyclopropanation/ring expansion cascade reaction. The author employed this rearrangement as the starting point in the design of a new macro cycle synthesis. The next part of the thesis focuses on the cycloisomerization of diynes involving as the first step of the process the rearrangement of one alkyne partner into an allene thanks to a gold-catalyzed 1,3-shift of a propargylic ester. The thesis discloses a new cycloisomerization pattern featuring a 1,5-carbonyl transfer, giving rise to unprecedented cross-conjugated diketones. In the final part of the research, Simmoneau investigates the gold-catalyzed cycloisomerization mechanism of 1,6-enynes and questions the intermediacy of gold acetylides. By the means of NMR and mass spectrometry analysis, theoretical treatment and solution experiments, it was possible to rule out the involvement of these species in the catalytic cycle. This thesis has led to a number of publications in high-impact journals.

The manufacture of polyolefins by metallocene catalysts represents a revolution in the polymer industry. The first, patent for a metallocene catalyst was filed in 1980 but it has been the last five years that have seen a dramatic increase in the volume of research into metallocenes and the maturing of metallocene technology. With contributions from leading experts from the US, Canada, Italy, Scandinavia, Germany and Japan, Metallocene-based Polyolefins gives comprehensive coverage of all areas of metallocene technology: catalyst structure, comonomer incorporation, polymerization mechanisms and conditions, reactor configurations, special properties, rheological and processing behaviour, comparison with conventional polyolefins and fields of application. An essential book for plastics engineers, polymer chemists, physicists, materials scientists and all those working in the plastics manufacturing and processing industries.

In this book the authors describe how they reproduced the redox functions of biocatalysts artificially. It includes the introduction and discussion of synthetic reactions via electron transfer, hybrid -conjugated systems, and biorganometallic conjugates as novel redox systems. The work was conducted in pioneering fields based on redox systems, in synthetic organic chemistry, synthetic materials chemistry, and bioorganometallic chemistry. The step-by-step process is illustrated by the three major parts of the book: redox reactions (selective synthetic methods using metal-induced redox reactions), redox systems (design and redox function of conjugated complexes with polyanilines or quinonediimines and molecular bowl sumanene), and design of bioorganometallic conjugates to induce chirality-organized structures (bio-related structurally controlled systems). This systematic and up-to-date description will be of special interest to graduate students who are meeting the new challenges of chemistry, as well as to post-doctoral researchers and other practicing chemists in both academic and industrial settings.

This thesis describes the synthesis and characterization of numerous metal-metal bonded complexes that are stabilized by extremely bulky amide ligands. It provides a comprehensive overview of the field, including discussions on groundbreaking complexes and reactions, before presenting in detail, exciting new findings from the PhD studies. The thesis appeals to researchers, professors and chemistry undergraduates with an interest in inorganic and/or organometallic chemistry.

Transition metal catalysis belongs to the most important chemical research areas because a ubiquitous number of chemical reactions are catalyzed by transition metal compounds. Many efforts are being made by industry and academia to find new and more efficient catalysts for chemical processes. Transition metals play a prominent role in catalytic research because they have been proven to show an enormous diversity in lowering the activation barrier for chemical reactions. For many years, the search for new catalysts was carried out by trial and error, which was costly and time consuming. The understanding of the mechanism of the catalytic process is often not very advanced because it is difficult to study the elementary steps of the catalysis with experimental techniques. The development of modern quantum chemical methods for calculating possible intermediates and transition states was a breakthrough in gaining an understanding of the reaction pathways of transition metal catalyzed reactions. This volume, organized into eight chapters written by leading scientists in the field, illustrates the progress made during the last decade. The reader will obtain a deep insight into the present state of quantum chemical research in transition metal catalysis.

The study of clusters is one of the most exciting topics in the rapidly developing field of nanostructured materials. As discussed in this book, nanometer-sized metal particles can be obtained not only by evaporation methods, producing atomic or molecular beams, but also by the chemical synthesis of metal cluster compounds. These have a well-defined stoichiometry and are composed of metal clusters of a given, homogeneous size, each cluster being surrounded by a shell of ligand molecules. Accordingly, the compounds provide excellent model systems for macroscopic assemblies of small metal particles embedded in a dielectric solid. The underlying physical properties are described in terms of a three-dimensional matrix of mutually separated quantum wells. In going from one compound to another, the size and separation of the quantum wells may be varied. In this way, one may study such fundamental properties as the size-induced transition from metallic to molecular behaviour. At the same time, the electronic level structure may be changed in a controlled way, which should confer tunable optical, electrical or magnetic properties.

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.

In many of the processes of oxidation catalysis, 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 contributors is the use of organic ligands to achieve efficient oxidation catalysis. Each volume of "Topics in Organometallic Chemistry" provides a comprehensive summary and critical overview of a specific topic in organometallic chemistry.

Covering everything from the basics to recent applications, this monograph represents an advanced overview of the field. Edited by internationally acclaimed experts respected throughout the community, the book is clearly divided into sections on fundamental and applied surface organometallic chemistry. Backed by numerous examples from the recent literature, this is a key reference for all chemists.

This book presents several helpful synthetic methods for diverse multinuclear complexes. The results described can be used to selectively connect mononuclear as well as multinuclear complexes with other metal complexes to construct valuable photofunctional compounds. Using the new synthetic methods, it was possible to selectively connect several types of metal complexes in a single step under relatively mild reaction conditions. This so-called building block approach utilizes various C-C coupling reactions between metal complexes with functional groups as active moieties. Owing to the large pi-conjugation systems, the multinuclear complexes synthesized using coupling reactions showed a strong absorption ability over a wide range of visible light and long emission lifetimes, which are ideal properties for photosensitizers and light absorbers. By combining these coupling methods with the newly developed hydrogenation reactions, the binding mode of the linkers in multinuclear complexes can be modified in order to tune the photophysical properties and photocatalytic ability. As such, the synthesized multinuclear complexes can be used for various purposes, e.g., as photocatalysts and photosensitizers, and in light-harvesting systems. The synthetic methods and strategies presented in this book diversify not only the structures but also functions of multinuclear complexes.

Advances in Polymer Science enjoys a longstanding tradition and good reputation in its community. Each volume is dedicated to a current topic, and each review critically surveys one aspect of that topic, to place it within the context of the volume. The volumes typically summarize the significant developments of the last 5 to 10 years and discuss them critically, presenting selected examples, explaining and illustrating the important principles, and bringing together many important references of primary literature. On that basis, future research directions in the area can be discussed. Advances in Polymer Science volumes thus are important references for every polymer scientist, as well as for other scientists interested in polymer science - as an introduction to a neighboring field, or as a compilation of detailed information for the specialist.

Advances in Organometallic Chemistry, Volume 72, contains authoritative review articles of worldwide researchers in organometallic chemistry. This longstanding serial is known for its comprehensive coverage of topics in organometallic synthesis, reactions, mechanisms, homogeneous catalysis, and more. Chapters in this updated release include Propargylidyne and Tricarbido Complexes, Metal carbonyl promoted multicomponent coupling of alkyne for synthesis of heterocyclic compounds, Group 10 metal(0) complexes stabilized by phosphorus and carbon donor ligands, Recent advances in gold catalyzed cycloadditions or Annulations of alkynes to access heterocyclic compounds, and Ion pairing and in situ ligand modification effects on the reactivity of molecular catalysts for olefin polymerization.