Organometallic compounds Subject

The first organometallic compound containing a cyclopentadienide (Cp = CsH5) ligand was CpNa, prepared in 1900.88 Only a year later, CpK was reported by the same authors.89 Several excellent review articles are available on the subject 90-92 here we review only recent information. 

Combustion of transition metal organometallic compounds produces a mixtures of simple compounds (metal oxides, carbon oxides, water, nitrogen) which is subject to exact analysis. Thermal decomposition or high temperature iodination of the same compounds cannot necessarily be expected to produce simple materials, with the result that identification is often a difficult problem. This is typified by diene derivatives of iron carbonyl10, where side reactions of the dienes (e.g. polymerization) follow disruption of the iron-diene bonds. The oligomeric mixture can be parti-... 

The introduction of metals into plasma polymers has been the subject of some research during recent years. Basically, three methods have been used (a) Plasma polymerization of organometallic compounds [79,80], (b) Concomitant etching or sputtering of metals [81] and (c) Evaporation of metals into a [82] plasma polymerization system. Munro et aL [83, 84] incorporated mercury into... 

Furthermore, the organometallic compounds (of which nickel and vanadium are the principal constituents) that are present to varying degrees in all residua and in the majority of heavy oils cause catalyst deterioration. Deposition of these metals in any form on to the catalyst leads to catalyst deactivation but the exact mechanism of deactivation is still subject to speculation. Nickel tends to be deposited throughout the catalyst whereas vanadium is usually more concentrated in the outer layers of the catalyst. In either case, catalyst deactivation is certain whether it be by physical blockage of the pores or destruction of reactive sites. 

Individual chapters deal with the determination of metals, non-metals, organic compounds and organometallic compounds in soil and in plants that grow in soil. A separate chapter deals with sampling procedures. A relationship between toxicant levels in soil and plants that grow in that soil has been established and is the subject of the concluding chapter. 

The chemistry of a class of organometallic compounds that contain a linkage between two different metallic and/or metalloidal elements has recently been the subject of considerable study (195, 207), but only very little interest has been shown in such compounds with the silicon-silicon-metal bond. Only a few derivatives of mercury and alkali metals are known. 

The speciation of redox-sensitive elements (e.g., Cr, Fe, and Mn), redox-sensitive elements that also form organometallic compounds (e.g., As), and redox-sensitive elements that also form organome-tallic and volatile compounds (e.g., Hg) in aquatic systems is discussed in this chapter. Because the scope of this subject is so large, only the dissolved phase in the aquatic system will be considered. 

H. Schumann and W. Genthe, Organometallic compounds of the rare earths 446 Subject index 573... 

Dimethylketene was subjected to polymerisations catalysed with various organometallic compounds. It was found to form highly crystalline polymers, the structure of which depended on the kind of organometallic catalyst used. 

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