Reviews homogeneous catalysis

Homogeneous catalysis by transition metal clusters has been reviewed from the perspective of the specific transformations.Examples of very mixed-metal clusters catalyzing processes homogeneously are collected in Table IX. As is generally the case with homogeneous catalysis, the catalytic precursor is well defined, but the nature of the active catalyst is unclear. 

Much of the recent interest in insertion reactions undeniably stems from the emphasis placed on development of homogeneous catalysis as a rational discipline. One or more insertion is involved in such catalytic processes as the hydroformylation (31) or the polymerization of olefins 26, 75) and isocyanides 244). In addition, many insertion reactions have been successfully employed in organic and organometallic synthesis. The research in this general area has helped systematize a large body of previously unrelated facts and opened new areas of chemistry for investigation. Heck 114) and Lappert and Prokai 161) provide a comprehensive compilation and a systematic discussion of a wide variety of insertion reactions in two relatively recent (1965 and 1967) reviews. 

Several reports covering carbonylation and other aspects of homogeneous catalysis include the hydroxycarbonylation reaction with palladium systems.310,311,629 A review summarizing the results and findings about the mechanism has been published.630 The carbonylation of vinyl... 

As with carboxylic acids obtained by palladium hydroxycarbonylation, their derivatives esters, amides, anhydrides and acyl halides are synthesized from alkenes, CO and HX (X = OR, NR2 etc.). The Pd-catalyzed methoxycarbonylation is one of the most studied reactions among this type of catalyzed carbonylations and has been reviewed and included in reports of homogeneous catalysis.625, 26 The methoxycarbonylation has been applied to many different substrates to obtain intermediates in organic syntheses as well as specific products. For instance, the reaction has been applied for methoxycarbonylation of alkynes666 Highly efficient homogeneous Pd cationic catalysts have been reported and the methoxycarbonylation of alkynes has been used to develop economically attractive and environmentally benign process for the production of methyl... 

The applications of coordination compounds in catalysis that have been shown are by no means the only important cases. In fact, there are numerous reactions in which homogeneous catalysis forms the basis for a great deal of chemistry. From the examples shown, it should be apparent that this is a vast and rapidly developing field. It is also one that is important from an economic standpoint. Although the basic principles have been described in this chapter, the literature related to catalysis is extensive. For further details and more comprehensive reviews of the literature, consult the references listed. 

The use of supramolecular ligand libraries in homogeneous catalysis was reviewed by Breit [54]. 

Homogenous catalysis in supercritical fluids has recently been reviewed by Noyori and coworkers [250]. 

Another solution to the problem of catalyst/product separation is the biphasic catalysis. The liquid biphasic catalysis became an attractive technology for potential commercial application of enantioselective homogeneous catalysis. The most important features of such systems are related to the fact that both reaction rate and e.s. may be influenced by the number of ionic groups in water-soluble ligand or by addition of surfactants. Descriptions of water-soluble ligands and the recent results in the rapidly progressing area of biphasic enantioselective catalysis are available in recent reviews [255,256],... 

The book presents a review of sixteen important topics in modem homogeneous catalysis. While the focus is on concepts, many key industrial processes and applications that are important in the laboratory synthesis of organic chemicals are used as real world examples. After an introduction to the field, the elementary steps needed for an understanding of the mechanistic aspects of the various catalytic reactions have been described. Chapter 3 gives the basics of kinetics, thus stressing that kinetics, so often neglected, is actually a key part of the foundation of catalysis. 

Sola, M. Duran, M. Torrent, M. The Dotz reaction A chromium Eischer carbene-mediated benzannulation reaction. In Computational Modeling of Homogeneous Catalysis Maseras, E. Lledos, A. eds. Kluwer Academic Boston 2002, 269—287. (Review). 

Meerwein-Pondorf-Verley reduction, discovered in the 1920s, is the transfer hydrogenation of carbonyl compounds by alcohols, catalyzed by basic metal compounds (e.g., alkoxides) [56-58]. The same reaction viewed as oxidation of alcohols [59] is called Oppenauer oxidation. Suitable catalysts include homogeneous as well as heterogeneous systems, containing a wide variety of metals like Li, Mg, Ca, Al, Ti, 2r and lanthanides. The subject has been reviewed recently [22]. In this review we will concentrate on homogeneous catalysis by aluminium. Most aluminium alkoxides will catalyze MPV reduction. 

In short, most work on POMs address primarily their pH of formation, the stability of the various complexes with emphasis on their analytical properties, homogeneous catalysis, radiochemical, and photochemical behaviors. All these properties have been described in a series of excellent reviews, which usually include short developments on their electrochemistry and redox catalysis properties [2-9, 24-28]. The reader is referred to these reviews for general descriptions of POMs synthesis, structures, and reactivity. Among these reviews, particular attention is drawn to those few containing substantial developments on electron transfer behaviors and the electrochemistry of POMs [2, 4, 5, 7-9, 24-28]. 

Comprehensive review G. Wagner, R. Herrmann, in Ferrocenes Homogenous Catalysis, Organic Synthesis, Materials Science, A.Togni, T. Hayashi (Eds.), VCH, Weinheim, 1995. 

For recent reviews see (a) P. W. lolly, G. Wilke, in Applied Homogeneous Catalysis with Organometallic Compounds (B. Gornils, W. A. Herrmann, Eds.),... 

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