Catalysis, supported metal complexes

Hj/CO) phase transfer catalysis supported metal complexes, liquid biphasic catalysis C0/H,0... 

These siUca-supported catalysts demonstrate the close connections between catalysis in solutions and catalysis on surfaces, but they are not industrial catalysts. However, siUca is used as a support for chromium complexes, formed either from chromocene or chromium salts, that are industrial catalysts for polymerization of a-olefins (64,65). Supported chromium complex catalysts are used on an enormous scale in the manufacture of linear polyethylene in the Unipol and Phillips processes (see Olefin polymers). The exact stmctures of the surface species are still not known, but it is evident that there is a close analogy linking soluble and supported metal complex catalysts for olefin polymerization. 

The unique catalytic properties of supported metal complexes, compared with different from metal and metal oxides, have been devoted to various chemical processes, including selective oxidation catalysis, shape selective catalysis and... 

Catalysis by Metals, Metal Compounds and Supported Metal Complexes... 

Leading references F. R. Hartley, Supported Metal Complexes, Reidel, Dordrecht, 1985 Yu. I. Yermakov, B. N. Kuznetsov and V. A. Zakharov, Catalysis by Supported Complexes, Elsevier, Amsterdam, 1981. 

In the following paragraphs, methods of preparation and characterization of structurally simple supported metal complexes are summarized, and examples are presented that illustrate characterization data and support general conclusions about structure, bonding, reactivity, and catalysis. 

Tada M, Iwasawa Y (2006) Advanced chemical design with supported metal complexes for selective catalysis. Chem Commun 27 2833... 

In the book, the section on homogeneous catalysis covers soft Pt(II) Lewis acid catalysts, methyltrioxorhenium, polyoxometallates, oxaziridinium salts, and N-hydroxyphthalimide. The section on heterogeneous catalysis describes supported silver and gold catalysts, as well as heterogenized Ti catalysts, and polymer-supported metal complexes. The section on phase-transfer catalysis describes several new approaches to the utilization of polyoxometallates. The section on biomimetic catalysis covers nonheme Fe catalysts and a theoretical description of the mechanism on porphyrins. 

An important research area of catalysis is the heterogenization of metal complexes showing excellent activity and selectivity in the homogeneous phase (hybrid catalysts) [1]. The main advantage of supported metal complexes over unsupported ones is the ease of separation from the reaction media, which makes them economically convenient [2]. On the other hand, the main problems related with the heterogenization on solid supports are metal complex leaching and decrease in catalytic activity. 

Solid-Supported Surface Catalysis by Metal Complexes. Hong et al. (1987a, b, in press) have prepared a variety of hybrid catalysts between Co(II) phthalocyanine complexes and the surfaces of silica gel, polystyrene-divinylben-zene, and Ti02 and tested these hybrids for catalytic activity with respect to the autoxidation of hydrogen sulfide, sulfur dioxide, 2-mercaptoethanol, cysteine, and hydrazine ... 

F. R. Hartley, Supported metal complexes, in Catalysis by metal complexes, R. Ugo and B. R. James, eds., Reidel, Dordrecht, 1985, ISBN 9027718555. 

A. A. Efendiev, D.D. Orudzhev, T.N. Shakhtakhtinskii, V.A. Kabanov, in Zakreplennye Metallkompleksy v Katalize Novosibirsk 1986, p. 138 (Supported Metal Complexes in Catalysis) (in Russian)... 

This monograph intends to acquaint the reader with the basic material available in the field of catalysis. Because this field was previously treated as a marginal area of polymer and catalytic chemistry, the authors mostly cite recent literature sources. It covers the catalytic properties of a broad class of functional polymers and their metal-ion complexes as well as ionite and heterogeneous (polymer-supported) metal-complex catalysis. 

E. R. Hartley, in Supported Metal Complexes, Catalysis by Metal Complexes (Eds. R. Ugo,... 

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