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.

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

Containing chemical, physical and structural data on 45,000 organometallics, this new edition of Dictionary of Organometallic Compounds is completely reviews and expanded. All compounds from the first edition have been reviewed, new references from the recent chemical literature have been added. Interesting new compounds, which have appeared in the literature from 1985 to 1993, have also been incorporated. A unique new feature is the Index of Synthetic Reagents, which groups compounds according to their use in synthetic organic chemistry. Compounds included: - organometallics representing all important structural types - compounds with an established use, such as orignard reagents, catalysts, starting materials, laboratory chemicals Type of information included: - accurate systematic chemical names, tradenames, trivial names - CAS Registry numbers - molecular formulae and weights - details on synthesis/preparation - uses in synthetic organic chemistry - physical data including melting/boiling points, solubility, magnetic susceptibility - concise bibliography

Homogeneous hydrogenation is one of the most thoroughly studied fields of homogeneous catalysis. The results of these studies have proved to be most important for an understanding of the underlying principles of the activation of small molecules by transition metal complexes. During the past three decades homogeneous hydrogenation has found widespread application in organic chemistry, including the production of important pharmaceuticals, especially where a sophisticated degree of selectivity is required. This volume presents a general account of the main principles and applications of homogeneous hydrogenation by transition metal complexes. Special attention is devoted to the mechanisms by which these processes occur, and the role of the recently discovered complexes of molecular hydrogen is described. Sources of hydrogen, other than H2, are also considered (transfer hydrogenation). The latest achievements in highly stereoselective hydrogenations have made possible many new applications in organic synthesis. These applications are documented by giving details of the reduction of important unsaturated substrates (alkenes, alkynes, aldehydes and ketones, nitrocompounds, etc.). Hydrogenation in biphasic and phase transfer catalyzed systems is also described. Finally, a discussion of the biochemical routes of H2 activation highlights the similarities and differences in performing hydrogenation in both natural and synthetic systems. For researchers working in the fields of homogeneous catalysis, especially in areas such as pharmaceuticals, plastics and fine chemicals.

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].

This paper summarizes some past and recent work from the author's laboratory on the reactions of carbon dioxide with metal complexes with the objective of suggesting the relevance of this research to some related biological systems. First, the various CO2-metal complex interactions in vivo and in vitro are briefly cited, followed by a description of the reversible activation of carbon dioxide by model rhodium and iridium compounds. Finally, recent results are presented on homogeneous catalytic hydrogenation/reduction of CO2 mediated by metal complexes, including a platinum cluster complex which catalyzes the carbon dioxide conversion at mild conditions. Keywords: Carbon dioxide, Metal complexes, Model compounds, Bicarbonato complexes, Homogeneous catalysis, Hydrogenation.

From the contents: Robert H Crabtree: Introduction and History. - Montserrat Diéguez, Oscar Pàmies and Carmen Claver: Iridium-catalysed hydrogenation using phosphorous ligands. - David H. Woodmansee and Andreas Pfaltz: Iridium Catalyzed Asymmetric Hydrogenation of Olefins with Chiral N,P and C,N Ligands. - Ourida Saidi and Jonathan M J Williams: Iridium-catalyzed Hydrogen Transfer Reactions. - John F. Bower and Michael J. Krische: Formation of C-C Bonds via Iridium Catalyzed Hydrogenation and Transfer Hydrogenation. - Jongwook Choi, Alan S. Goldman: Ir-Catalyzed Functionalization of CH Bonds. - Mark P. Pouy and John F. Hartwig: Iridium-Catalyzed Allylic Substitution. - Daniel Carmona and Luis A. Oro: Iridium-catalyzed 1.3-dipolar cycloadditions.

The authors distill the most relevant applications of recyclable homogeneous catalysts rather than list every example found in the field. This provides a framework to the readers, allowing them to ask the most relevant questions about recyclable homogeneous catalysis applications in their area of interest. Recyclable Homogeneous Catalysis uses physical and chemical engineering methods specifically designed for high recoverability. Some of the recovery methods include the use of multi-phasic solvent systems, distillation, and extractions. In addition, by using careful catalyst design, the active metal center can be embedded onto a solid support or polymer to increase recoverability. The catalysts discussed in this primer are used in a range of reactions such as polymerization, CO2 capture, and amination. Graduate students and early career professionals who want to get into the field of recyclable catalysts will benefit from reading this work.

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.

A pioneer work on catalysis of organic chemical reactions involving multinuclear metal complexes. Catalysis by Di- and Polynuclear Metal Cluster Complexes surveys the latest developments at the frontier of this exciting field, combining theory with new and original examples of catalytic processes produced by polynuclear metal complexes. An invaluable resource for inorganic and organometallic chemists in industry and R&D, it contains chapters from world experts and scholars on: Concepts and models for characterizing homogeneous reactions catalyzed by transition metal cluster complexes Activation of ruthenium clusters for use in catalysis Catalysis by mixed metal clusters containing gold phosphine groupings Catalysis by sulfido bridged dimolybdenum complexes Dimolybdenum and ditungsten complexes Synthesis of organic compounds catalyzed by transition metal clusters Catalysis with dirhodium (II) complexes Catalytic synthesis of polythioether macrocycles Catalysis of Rh, Rh-Co, and Ir-Co multinuclear complexes and its applications to organic syntheses Bimetallic hydroformylation catalysis Catalysis by colloids Catalysis with palladium clusters Heterometallic clusters for heterogeneous catalysis Supported clusters in catalysis.