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Aluminum complex compounds

Aluminum acetylacetonate, 2 25 Aluminum bromide, 3 30 of high purity, 3 33 Aluminum chloride, compound with selenium(IV) chloride, 5 127 Aluminum complex compounds, anions, oxalato, K3[A1(Cs04)3]-3HsO, 1 36... [Pg.224]

Further deprotonation, dehydration, and polymerization of monomers and dimers may yield ringlike stmctures of hydroxy—aluminum complexes (10). Coalescence of ring compounds into layers by further growth results in the formation of crystalline aluminum hydroxide at pH 6, the point of minimum aqueous solubiUty. [Pg.136]

In the presence of Eriedel-Crafts catalysts, gaseous ethyl chloride reacts with ben2ene at about 25°C to give ethylben2ene, three diethylben2enes, and other more complex compounds (12) (see Xylenes and ethylbenzene). Aromatic compounds can generally be ethylated by ethyl chloride in the presence of anhydrous aluminum chloride (see Eriedel-Crafts REACTIONS). Ethyl chloride combines directly with sulfur trioxide to give ethyl chlorosulfonate,... [Pg.2]

The anthocyanins are pH sensitive. Their color, in part, is deterrnined by the pH of the sap. Cyanin, for example, is red at pH 3, violet at 8, and blue at 11. However, there are other factors that affect the colors of the anthocyanins metallic salts, notably iron and aluminum, react with those anthocyanins containing vicinal hydroxy groups and produce highly colored complex compounds. Other factors are the colloidal condition of the cell sap and copigmentation (91). [Pg.400]

The mechanism of the cycloaddition reaction of benzaldehyde 2a with Danishefsky s diene 3a catalyzed by aluminum complexes has been investigated theoretically using semi-empirical calculations [14]. It was found that the reaction proceeds as a step-wise cycloaddition reaction with the first step being a nucleophilic-like attack of Danishefsky s diene 2a on the coordinated carbonyl compound leading to an aldol-like intermediate which is stabilized by interaction of the cation with the oxygen atom of the Lewis acid. The next step is the ring-closure step, giving the cycloaddition product. [Pg.159]

The mechanism for the hetero-Diels-Alder reaction of benzaldehyde 9 with the very reactive diene, Danishefsky s diene 10, catalyzed by aluminum complexes has been investigated from a theoretical point of view using semi-empirical calculations [27]. The focus in this investigation was to address the question if the reaction proceeds directly to the hetero-Diels-Alder adduct 11, or if 11 is formed via a Mukaiyama aldol intermediate (Scheme 8.4) (see the chapter dealing with hetero-Diels-Alder reactions of carbonyl compounds). [Pg.316]

Anthraquinone, 1-hydroxy-calcium aluminum chelate compound, 1,2 metal complexes dyes, 6,86 Antiarthritis drugs labelled gold compounds, 6, 969 metal complexes, 6,758 Antibiotic M139163,2, 974 Antibiotics ionophoric, 6, 553 metal complexes selective binding, 6, 552... [Pg.84]

The different ratios of 52/53 produced by cycloadditions performed at atmospheric and high pressure, and the forma tion of the unusual trans adducts 53, have been explained by the facts that (i) Diels-Alder reactions under atmospheric pressure are thermodynamically controlled, and (ii) the anti-endo adducts 52 are converted into the short-lived syn-endo adducts 54 which tautomerize (via a dienol or its aluminum complexes) to 53. The formation of trans compounds 53 by induced post-cycloaddition isomerization makes the method more flexible and therefore more useful in organic synthesis. [Pg.212]

Yu et al. synthesized two methyl-substituted Alq3, named tris(2,3-dimethyl-8-hydroxy-quinoline) aluminum complex (Alm23q3, 237) (Scheme 3.72) [264]. This compound emits blue color with an emission peak centered at 470 nm and FWHM of 90 nm. OLEDs with a structure of ITO/TPD/Alm23q3/Mg Ag emit blue light and the luminous efficiency is 0.62 lm/W with a maximum luminance of 5400 cd/m2 at 19 V. [Pg.364]

U.S. 5,466,392 Organic electroluminescence device and compound having an aluminum complex structure... [Pg.652]

Since the discovery by Ziegler and Natta that transition metal complexes, in the presence of aluminum alkyl compounds, can efficiently catalyze the polymerization of ethylene and propylene, significant efforts have been devoted to the development of new catalytic systems for polymerization of olefins. One of the... [Pg.61]

Equation (3)]. Polymerization of PO also proceeds rapidly to give the low molecular weight PPO [J/n = 4050 g mol— 1.2]. Since the molecular weight of polymer indicates that less than 10% of aluminum sites are active for producing the polymer, an oligomeric aluminum complex is supposed to be an active species although the characterization is not fully achieved. In this system, exclusion of a coordinated compound such as THE is essential for the high catalytic activities. Thus, aluminum complex prepared by the reaction of APBus and methylphosphonic acid in the presence of THE exhibits much less catalytic activity. [Pg.605]

Conversion in the liquid phase has the disadvantage that the carbon tetrachloride formed during the disproportionation of trichlorofluoromethane forms a complex compound with the aluminum trichloride possessing no catalytic effect, so that only a relatively small amount of trichlorofluoromethane can be converted with a predetermined amount of aluminum trichloride. The continuous gas-phase method in a tubular reactor is more practicable the temperature at which it takes place must be high enough to prevent any products from condensing on the catalyst. It is also possible to perform the disproportionation process continuously in the liquid phase in a tubular reactor, under pressure and at an increased temperature. In this case aluminum trichloride must first be activated by pretreatment (partial fluorination), since the partial fluorination of aluminum trichloride greatly reduces the tendency for complex compounds to form with the chlorinated hydrocarbon when this itself has formed. [Pg.282]

Another broad class of compounds are the bridged carbene complexes. These compounds contain two identical or two different metal centers with the carbene centers bonded to both of the metal atoms in a bridging relationship. However, these binuclear complexes generally do not show classical carbene reactivity and will therefore not be discussed further, except to mention briefly the special case of the titanium-aluminum complex (3) developed by Tebbe and Grubbs and their coworkers.101 This, and related complexes, has proven to be particularly useful in organic synthesis, although its principal importance is in reactions other than cyclopropanations. [Pg.979]


See other pages where Aluminum complex compounds is mentioned: [Pg.224]    [Pg.224]    [Pg.224]    [Pg.224]    [Pg.207]    [Pg.247]    [Pg.766]    [Pg.739]    [Pg.73]    [Pg.327]    [Pg.87]    [Pg.107]    [Pg.48]    [Pg.233]    [Pg.234]    [Pg.640]    [Pg.279]    [Pg.280]    [Pg.98]    [Pg.118]    [Pg.19]    [Pg.411]    [Pg.510]    [Pg.597]    [Pg.604]    [Pg.14]    [Pg.42]    [Pg.106]    [Pg.164]    [Pg.382]   


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Aluminum complex compounds anions, oxalato

Aluminum complexation

Aluminum compounds Lewis acid complexes

Molybdenum complexes Aluminum compounds

Zirconium compounds aluminum complexes

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