Halides organoaluminums

Catalysts giving C6-C20 olefins in very high yield and purity (95%), containing Zr halides, organoaluminum compounds and sulfides, disulfides, tio-phenes, thiourea, phosphines, or primary amines are described in Idemitsu Petrochemical Co. Ltd. patents [111-113]. 

The alkylation of tin tetrachloride with organolithium compounds, Grignard reagents, or organoaluminum compounds remains the most common route to tetraalkyltins, and thence, by the Kocheshkov disproportionation, to the various organotin halides. 

Group 14 metal halides also undergo metathesis reactions. For instance, organotin compounds are prepared on an industrial scale using organoaluminum reagents. These reactions take place because tin is a softer Lewis acid than aluminum, and carbon (in an alkyl group, represented by R) is a softer Lewis base than chlorine ... 

The Diels-Alder adduct of 1,5-cyclooctadiene with hexachlorocyclo-pentadiene was homopolymerized or copolymerized (113) with cyclic olefins using tungsten halide salts with either organoaluminum or organo-tin cocatalyst to give thermally stable flame- and oil-resistant polymers. 

Organoaluminum compounds couple very well with tertiary (to give products containing a quaternary carbon) and benzylic halides at -78°C.1301 This reaction can also be applied to allylic, secondary, and some primary halides, but several days standing at room temperature is required (see also 0-90). Products containing a quaternary carbon can also be... 

Cleavage of ethers Organoaluminum reagents, 202 Decarbonylation of acyl halides Tetrakis(triphenylphosphine)palla-dium(0), 289 Dehalogenation... 

The mechanism of addition of aikylmagnesium halides to double bonds has been the subject of intensive investigation.6 According to the current interpretation, these reactions differ significantly in mechanism from reactions with organoaluminum species under similar reaction conditions. For this reason no general mechanism for can be lormulated carbometallation reactions. 

No reaction occurs when triethylaluminum, aluminum chloride, stannic chloride, titanium tetrachloride, diethylzinc or triethylboron are used in lieu of an organoaluminum halide or sesquihalide. 

In later communications (27, 28) Hirooka reported that in addition to acrylonitrile, other conjugated monomers such as methyl acrylate and methyl methacrylate formed active complexes with organoaluminum halides, and the latter yielded high molecular weight 1 1 alternating copolymers with styrene and ethylene. However, an unconjugated monomer such as vinyl acetate failed to copolymerize with olefins by this technique. 

Although the yield of copolymer is higher when the organoaluminum halide is used as catalyst in lieu of the peroxide, the combination of the two gives a 3-5 times higher yield. However, since the product is essentially the same 1 1 copolymer in either case, as compared with the entirely... 

The direct interaction of Al, H2, and olefin (hydroalumination) is used to give either the dialkyl hydrides or the trialkyls. These are also accessible by reduction of organoaluminum halides and exist as dimers or trimers, depending on the steric requirements of the alkyl or aryl group. Examples are [Bu2A1H]3, [mes AlH2]2, and mes GaH2.24... 

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