Magnesiums aluminum halides

The magnesium aluminum halide tends to dissociate in ethereal solvents to form magnesium and aluminum halides ... 

E.C. Ashby, R.D. Schwartz, B.D. James, Concerning the preparation of magnesium aluminum hydride. A study of the reactions of lithium and sodium aluminum hydrides with magnesium halides in ether solvents , Inorg. Chem. 9 (1970) 325-332. 

Silica is reduced to silicon at 1300—1400°C by hydrogen, carbon, and a variety of metallic elements. Gaseous silicon monoxide is also formed. At pressures of >40 MPa (400 atm), in the presence of aluminum and aluminum halides, silica can be converted to silane in high yields by reaction with hydrogen (15). Silicon itself is not hydrogenated under these conditions. The formation of silicon by reduction of silica with carbon is important in the technical preparation of the element and its alloys and in the preparation of silicon carbide in the electric furnace. Reduction with lithium and sodium occurs at 200—250°C, with the formation of metal oxide and silicate. At 800—900°C, silica is reduced by calcium, magnesium, and aluminum. Other metals reported to reduce silica to the element include manganese, iron, niobium, uranium, lanthanum, cerium, and neodymium (16). 

It is, therefore, to be expected that a compound such as trimethyl-methylene stiborane, (CHs SbCtE, should be relatively unstable and attempts to synthesize this species would have to be carried out at low temperature. Another difficulty arises from the experimental fact (104) that all conventional methods of synthesis for stibonium ylides lead to pentaalkylstiboranes instead of ylides (see Introduction). Thus mcthyl-ation of (CH3)4SbX or (CHY) sHbX2 halides by organometallic reagents of lithium, magnesium, aluminum, or zinc invariably yield (CHY) 5Sb as the sole product. 

In order to prepare organoaluminum compounds with specific functional groups in the alkyl radical, reactions of aluminum halides with various metallic compounds are particularly important. Thus, vinyl magnesium halides and aluminum trichloride give unstable trivinylalane (see Section III,B,2) (17, 288) ... 

Whereas the preparation of aliphatic aluminum compounds from appropriate element alkyls and aluminum halides is now of interest only in special cases (see Sections II,A,3 and IV,B), the route to aryl aluminum compounds from aryl magnesium halides and aluminum halides or from either aluminum or trialkylamine alanes and mercury diaryls is still useful (174, 48). 

They can be used suspended with an aluminum halide in benzene or an alkylated benzene. Magnesium hydride is also the active agent in a cyclic process involving H2 (63). In the absence of a solvent, calcium hydride will react with gaseous BF3 at 225 C according to... 

This is the most commonly utilized method for synthesis of transition metal complexes with M —C a bonds. The following substrates are utilized halides, acetylacetonates, acetates, /-electron element alcoholates, as well as organometallic compounds of lithium, magnesium, aluminum, sodium, zinc, mercury, elements of group 14, etc. Ethers and hydrocarbons are used as solvents. In general, the synthesis should be carried out at lower temperatures and under inert atmosphere. 

Organolithium compounds react with alkylmetals or metal halides such as boron, magnesium, aluminum, copper, zinc and tellurium compounds, and the reactions give the ate complexes as shown in eqs. (3.32) and (3.33) [78]. 

Preparation. Uranium metal may be prepared by several methods the reduction of uranium oxides with carbon In an arc-melting furnace reduction of uranium oxides with magnesium, aluminum, calcium or calcium hydride the reduction of uranium halides with alkali or alkaline-earth metals electrolytic reduction of uranium halides and the themal decomposition of uranium Iodide. 

The yield of product is increased to 81% (analyzed by evolution of M-butane) if 0.67 g. (0.0033 mole) of aluminum isopropoxide is added to the suspension of magnesium before addition of the halide solution. Alternatively, an equivalent amount of 2-propanol and iodine (giving 0.01 mole of CsII OMgl) may be added. These modified procedures (particularly the second) also shorten the induction periods and render unnecessary any special drying of the reagents and apparatus and the use of fresh magnesium. 

Halomet [Halogen metal] A process for reducing halides to metals by reaction with metallic aluminum or magnesium in a closed vessel. Invented in 1968 by R. Nowak and W. Schuster at Halomet, Basle. 

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