Organometallic compounds from elemental metals

The number of compounds and combinations of compounds that fit into the category of Ziegler-Natta catalysts are far too numerous to describe here. However, a Ziegler-Natta catalyst may be simply defined as a combination of two components (1) a transition metal compound of an element from groups IVB to VIIIB, and (2) an organometallic compound of a metal from groups I to III of the periodic table. The transition metal compound is referred to as the catalyst and the organometallic compound as the cocatalyst. A combination of the catalyst and the cocatalyst is often referred to simply as the catalyst. 

The HFOs also contain organometallic compounds from their presence in the virgin crude oil. Such trace metal is Va. Other elements that occur are Ni, Fe, K, Na, Al, and Si. Significant concentrations of H2S (hydrogen... 

The formation of organometallic compounds from metals is described in Ch. 5. In this section, a few references are given, dealing with the formation of such compounds by an exchange reaction (transmetallation or ligand exchange) imder solid-liquid conditions and the preparation of compoimds containing non-metal elements. 

At some stage, an atom or an ion must be released from the solid metal to give a soluble organometallic compound, an elemental step during which the halide ion and the solvent properties play an important role. The more "reactive"... 

The fundamental Ziegler-Natta recipe consists of two components the halide or some other compound of a transition metal from among the group IVB to VIIIB elements and an organometallic compound of a representative metal from groups lA to IIIA. Some of the transition metal compounds that have been... 

Organometallic compounds are defined as compounds containing a direct link between a carbon atom and a metal. What constitutes a metal for nomenclature purposes is really rather vague. The practice in nomenclature is to consider any element other than C, H and the rare gases to be metals if this is useful. The names of such compounds reflect their constitution and are drawn both from organic nomenclature and from inorganic nomenclatures. The names of organometallic compounds demonstrate that nomenclatures must be unified and adaptable to any situation. 

Table 12.1 shows some organometallic lithium compounds. It is seen from their formulas that these compounds are ionic. As discussed in Section 12.2, 1A metals have low electronegativities and form ionic compounds with hydrocarbon anions. Of these elements, lithium tends to form metal-carbon bonds with the most covalent character therefore, lithium compounds are more stable (though generally quite reactive) than other organometallic compounds of group 1A metals, most... 

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