Aluminum chloride alkylation

Diethylamino)sulfur trifluoride, 110 Formylation (see also Carbonylation) Vilsmeier reagent, 341 Fragmentation reactions Cerium(IV) ammonium nitrate, 67 Copper(II) acetate-Iron(II) sulfate, 85 Lead tetraacetate, 155 Friedel-Crafts alkylation Aluminum chloride, 15... 

In alkyl aluminum chlorides of the type RxAlyClz two different chemical moieties which cause alkylation as well as chlorination are present in one molecule. Therefore, RAAL,Clz-type activators do not require the separate addition of other halide donors in order to achieve high cis-1,4-contents. In Nd-based catalyst-systems the dual role of RXA1 C1Z compounds is demonstrated by Watanabe and Masuda [364], These findings only hold true for Nd-based catalyst systems. For lanthanum-based catalyst systems Lee et al. found that the use of alkyl aluminum chlorides results in trans- 1,4-polymerization (93-94%) [371]. However, usually, in Nd catalysts the alkylating power of RxAlyClz is not sufficient at the applied amounts of RXA1 C1Z. Thus, an additional standard cocatalyst has to be added for the activation of the Nd precursor. 

Nd-precursors. These additives comprise alcohols, organic acids, esters of organic acids, lactones of organic acids, tributyl phosphate, tripenylphosphin, diethyl phosphinoethane, diphenyl phosphinoethane, acetylacetonate, tri-ethylamine, AbN -dimclhyl acetoamide, tetrahydrofuran, diphenylether etc. In this context alkyl aluminum chloride which is prereacted with TBP is worth mentioning [386,387]. 

Other neodymium precursors such as Nd phosphates and Nd allyls are most commonly applied in combination with alkyl aluminum chlorides. The principles outlined for the selection of the appropriate halide for Nd... 

An intensive study of R2AlCl-induced cyclization of unsaturated carbonyl substrates was made by Snider and co-workers. Their results show the advantage of alkyl-aluminum chloride over AICI3 in Lewis acid-catalyzed reactions, because these reagents can act as proton scavengers and Lewis acids. The reaction is interpreted as a Me2AlCl-promoted cyclization of the y,(5-unsaturated ketone then sequential hydride and methyl shift, as depicted in Sch. 25 [49],... 

On decomposition of the 1 1 adduct of phenyl azide with both alkyl aluminum chlorides, the main reaction is A-ethylation with the formation of IV-ethylanilides 100). 

The direct and selective 3-acylation of both acid- and base-sensitive indoles 6 can be efficiently achieved using acyl chlorides and alkyl aluminum chlorides without NH protection (Scheme 2.3). When acyl chlorides are used for the acylation of indoles, liberation of hydrogen chloride is unavoidable, and the reaction results in the production of tar materials mainly due to polymerization of indole. Alkylaluminum compounds are utilized to scavenge the acid in the acylation with acyl chlorides. The reaction proceeds cleanly to give 3-acylindoles 7 without any by-product formation. The use of triethylaluminum leads to lower yields, probably because a nucleophilic attack of the alkyl group to acyl chloride occurs competitively. As expected, the use of aluminum... 

ALLILE (CLORURO di) (Italian) (107-05-1) Forms explosive mixture with air (flash point -20°F/-29°C). Violent polymerization and explosion may occur from elevated temperatures, light, acid catalysts, ferric chloride, aluminum chloride, Lewis acids, or Ziegler catalysts, finely divided metals. Violent reaction with oxidizers, alkyl aluminum chlorides. Incompatible with strong acids, oleum, amines, aluminum chloride, boron trifluoride, chloro-sulfonic acid, ethylene diamine, ethyleneimine, ferric chloride, sodium hydroxide. Slow decomposition with moisture. Attacks some coatings, plastics, and rubber. Corrosive to steel. Flow or agitation of substance may generate electrostatic charges due to low conductivity. 

CHLOROPROPENE (107-05-1) Forms explosive mixture with air (flash point — 20°F/—29°C). Violent polymerization and explosion may occur from elevated temperatures, light, acid catalysts, ferric chloride, aluminum chloride, Lewis acids, or Ziegler catalysts, finely divided metals. Violent reaction with oxidizers, alkyl aluminum chlorides. 

HAZARD RISK Fire and explosion hazard when exposed to heat, flame or oxidizers extremely flammable vigorous or explosive reaction above -70°C with alkyl aluminum chlorides and aromatic hydrocarbons violently exothermic polymerization reaction with Lewis acids and metals NFPA Code H 3 F 3 R 1. 

EXPLOSION and FIRE CONCERNS dangerous fire and explosion hazard extremely flammable liquid NFPA rating Health 3, Flammability 3, Reactivity 1 vigorous or explosive reaction above -70°C with alkyl aluminum chlorides and aromatic hydrocarbons violently exothermic polymerization reaction with aluminum chloride, boron trifluoride, sulfuric acid incompatible or reacts strongly with nitric acid, ethylene imine, ethylenediamine, chlorsulfonic acid, oleum, sodium hydroxide combustion will produce carbon dioxide, carbon monoxide, and hydrogen chloride use carbon dioxide, alcohol foam, or dry chemical for firefighting purposes. 

Early Soluble Unbridged Metallocene Catalysts in Connection with Alkyl Aluminum Chlorides... 

Low-molar-mass poly(butadiene) oils with 80%-97% cw-1,4 contents are produced with other Ziegler catalysts (for example, cobalt compounds with alkyl aluminum chlorides or nickel compounds with trialkyl aluminum and boron trifluoride-etherate). The products have few cross-links and dry as fast as wood oil and faster than linseed oil. Conversion of the poly (butadiene) oils with 20% maleic anhydride gives air-drying (air-hardening) alkyd resins. Modified poly (butadiene) oils stabilize erosion-endangered soils. Because of its low viscosity, the aqueous emulsion penetrates the surface soil layers. The surface crust is reinforced by an oxidative bonding process. Since no skin is formed on the soil crust, the aqueous absorption characteristics of the soil are retained. 

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