Organometallic compounds aluminium

Many metals occur in crude oils. Some of the more abundant are sodium, calcium, magnesium, aluminium, iron, vanadium, and nickel. They are present either as inorganic salts, such as sodium and magnesium chlorides, or in the form of organometallic compounds, such as those of nickel and vanadium (as in porphyrins). Calcium and magnesium can form salts or soaps with carboxylic acids. These compounds act as emulsifiers, and their presence is undesirable. 

The catalyst component consists of halides of IV-VIII group elements having transition valence and the cocatalysts are organometallic compounds like alkyls, aryls and hydrides of group I-IV metals. Although there are hundreds of such catalyst cocatalyst systems listed in table below. Systems based on the organoaluminium compounds such as triethyl aluminium (AlEt3) or diethyl aluminium chloride... 

In recent years new types of carbanions have been prepared which are paired with different metals and this has found the basis for the preparation of many novel organometallic compounds. Some of these metals include group IA, IIA metals besides aluminium, zinc and cadmium. 

A. McKillop, J. D. Smith, and 1. J. Worrall, Organometallic Compounds of Aluminium, Gallium, Indium and Thallium. Chapman Hall, London, 1985. 

In the second paper [118] tin, iron and nickel organometallic compounds were separated using aluminium-clad high temperature columns coated with 0.1 xm films of HT-5. Various column lengths and temperature gradients were used to separate the species. Helium was used as the carrier gas. The same GC-ICP-MS set up was used as in the previous paper with slight modification of the transfer line for the analysis of nickel diethyldithiocar-... 

Another general type of mechanism has been proposed for the reaction of a-haloalkyl aluminium compounds with olefins (Hoberg, 1962). This involves initial addition of the organometallic compound across the double bond followed by a y-elimination (equation 18). The evidence... 

Furukawa et al. [274] and Natta cl al. [275,276] succeeded independently in the preparation of crystalline polyacetaldehyde by using some organometallic compounds, such as diethylzinc or triethylaluminium, for the low-temperature polymerisation of acetaldehyde. Metal alkyls and metal alkoxides, e.g. aluminium isopropoxide, zinc ethoxide or ethyl orthotitanate, have also polymerised other aldehydes such as propionaldehyde and trichloroacetaldehyde to give crystalline polymers (Table 9.3) [270,275,277], A highly crystalline isotactic polymer has been obtained from the polymerisation of w-butyraldehyde with triethylaluminium or titanium tetrachloride-triethylaluminium (1 3) catalysts. Combinations of metal alkyl, e.g. diethylzinc, with water [278] or amine [279] appeared to give very efficient catalysts for aldehyde polymerisations. 

Organometallic compounds (except for alkyl aluminium and alkyl lithium compounds)... 

The application of organometallic compounds or hydrides of the more electropositive main group metals lithium, magnesium or aluminium in organic synthesis, catalysis and polymerization is due to the polarity of the metal/carbon and metal/hydrogen bonds, i.e. to the considerably unsymmetrical electron distribution M —or —respectively. While there are... 

The mercury may be replaced from mercury dimethyl by sodium, magnesium, zinc, or aluminium under suitable condition with formation of organometallic compounds of these metals with mercury diethyd, the reaction takes place with sodium, magnesium, cadmium, beryllium, zinc, aluminium, bismuth, and tellurium with mercury di-n-propyl, the metals sodium, beryllium, zinc and aluminium react, and sodium also reacts with mercury di-n-octyl. 

The tribochemical reactions of these additives with aluminium are very interesting, especially from the point of view of organometallic products resulting from alcohols. The aluminium rolling process produces abrasive particles and organometallic compounds, mostly called soaps, resulting from the reaction between fatty additives and the fresh unoxidized metal surfaces produced during... 

General works which are of interest include a book on the chemistry of all four heavier elements, and reviews of metal-metal bonded organometallic compounds and low valent or paramagnetic aluminium species. ... 

Organometallic compounds of aluminium, gallium, indium and thallium... 

C ataly st/cocataly St Organometallic compound, Aluminium alkyl Organometallic compound, Aluminium alkyl Organometallic compound. Aluminium alkyl... 

In 1958, poly(ethylene oxide)s of very high molecular weight became available. These products range in molecular weight from about 100 000 to 5 x 10 and above. Details of the techniques used to manufacture these polymers have not been disclosed, but the essential feature is the use of (generally) heterogeneous initiator systems. Effective initiators are mainly of two types, namely alkaline earth compounds (e.g., carbonates and oxides of calcium, barium and strontium) and organometallic compounds (e.g., aluminium and zinc alkyls and alkoxides, commonly with added co-catalysts). 

Longi and Mazzochi describe the gas chromatography of the organometallic compounds of beryllium, zinc, boron, aluminium and antimony. 

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