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Interaction of Metals with Alcohols

The most active metals react with alcohols as acids and produce metal alkoxides together with hydrogen gas as by-products  [Pg.209]

The reaction is facile at room temperature and in the absence of catalysts only for alkali metals (M = Li, Na, K) and barium [59]. To obtain the derivatives of alkaline earth metals with aliphatic alcohols, it is necessary to apply heat (reflux) and add a catalyst, usually elementary iodine, to clean the surface of the metal applied [110]. The same is true for aluminum alkoxides that can be produced in high yields by reaction of aluminum metal with dry alcohols on addition of l2(s) [2]. For drying the alcohols, one can apply aluminum alkoxides produced even from household aluminum foil, but it is necessary to remember that the latter is doped by some few percent of iron and is not a suitable material for the synthesis of aluminum alkoxides for preparation of high-purity ceramics. [Pg.209]

Even alkoxides of rare earth elements can be synthesized by direct interaction of metals with alcohols (usually PrOH taken in 1 1 or 1 2 mixtures with toluene to increase the boiling point) [111] on reflux or addition of mercury(II) chloride as catalyst. In the latter case, the reaction is usually quite slow and thus takes long time. It is advantageous to use flne metal turnings for this purpose. [Pg.209]

It is worth noting that the reaction of metals with functional alcohols forming stable complexes with metal cations is most often much more facile than with the aliphatic ones. Both alkaline earth (Mg, Ca, Sr) and rare earth elements do react with alkoxy alcohols such as 2-methoxy-ethanol (now prohibited from use in European Union because of its toxicity) on reflux without the need of addition of a catalyst. Even tin can be converted into Sn(II) alkoxides by a catalyst-free reaction with amino alcohols under high temperatures and pressures [112]. [Pg.209]


The interaction of metal with alcohol (on catalytic action of BeCl2, HgCl2 or I2) is used only for the synthesis of the ethoxide, which precipitates on reflux (method 1). In the case of MeOH or PrOH, the stable viscous liquid alkoxide halids are formed [1645, 1624, 1120]. The electrochemical approach (method 2) was applied only for the preparation of Be(OC2H4OMe)2 [1652],... [Pg.211]

The main idea of these techniques lies in the interaction of the active hydrogen atom of the alcohols with the anions of metal hydrides, alkyls, acetylides, nitrides, amides, dialkylamides, bis(trialkylsilyl)amides, sulfides, etc., with formation of compounds where an H atom is bonded by a strong covalent bond (usually gaseous HX). Alkaline hydrides of the most active metals (K, Rb, Cs) are used to slow down the reaction of metal with alcohol sometimes it is necessary simply to avoid explosion. [Pg.19]

Obviously, more quantitative work is essential to explore the extent and course of side-reactions in the interactions of metals with different alcohols under varying experimental conditions. [Pg.17]

Diselenophosphate complexes are prepared from the interaction of metal salts and complexes with appropriate diselenophosphoric acid or its salt. The acids are obtained from the reaction of phosphorus(V) selenide with alcohols 229). The preparation of phosphorus(V) selenide and its reactions with alcohols 229) and amines 22°) have been described and a variety of complexes reported (Table 4). The biological activity of these compounds does not seem to have described but the exercise of extreme caution when handling these materials is recommended. Zingaro and his coworkers 229-232) thoroughly characterized the thermal and spectroscopic properties of a number of compounds. [Pg.77]

Interaction of Molecules with Particle Surface. We could not explain the observed stability of metal sols in alcohol over several months within the traditional... [Pg.542]

The general structure of alkali metal alcoholates of polyhydroxy compounds is probably very similar to those proposed by Martell and Calvin1 for the alkali metal chelates of o-salicylaldehyde (see Figs. 9 and 10). 148 1M>IM Unfortunately, because of the highly amorphous nature of nearly all pf the alcoholates and adducts formed by the interaction of metal hydroxides with carbohydrates, x-ray diffraction studies have failed to furnish information regarding the precise location of the metal in these complexes. [Pg.265]

This method hitherto has been the most commonly used for the synthesis of metal alkoxides the reaction is usually carried out in alcohols. That is why at first some considerations concerning interaction of metal halogenides with alcohols should be made. It has been emphasized by Tishchenko [1585] that dissolution of ZnCl2 in alcohols is accompanied by vigorous reaction leading to ZnCl (OR)2 , accompanied by evolution of HC1, and followed by further reaction ... [Pg.21]

A modification of this route is a simultaneous reaction of two metals with alcohol that can be considered as the in situ reaction of the alkoxides formed. Thus the interaction of Mg and A1 with ethanol (leading to the formation of the perfectly soluble MgAl2(OEt)8) occurs very rapidly and does not need activation, in contrast with the reactions of individual metals with alcohol, leading to polymeric Mg(OEt)2 andAl(OEt)3 [1101, 887] (see Section 2.1). The preparation of the heterometallic derivatives has been achieved even via anodic oxidation of one metal in solution of the other (the complex solutions obtained have been used for the deposition of films in sol-gel technique) [1777]. [Pg.100]

Application of the alcohol interchange reaction (method 6) is limited by certain phenols and also di and trisubstituted glyoxides (while the reaction of metals with glycols gives only monosubstituted derivatives) [745, 621, 575, 1584,1369]. As redox processes (method 7) can be considered the Grignard-type reactions — the interaction of metal alkyls with carbonyl compounds,... [Pg.161]

The synthesis of fluorinated butoxides was carried out by interaction of metal hydrides with corresponding alcohols in ether media [467, 947]. The interaction of fluorinated ketones with sodium in THF or aqueous alkali led to the derivatives of perfluoropinacol ... [Pg.198]

The most stable turned out to be the derivatives ofcarbinols (CF3)nHmMe3HMnCOH and fluorinated phenols. They are described for Li, Na, and Ba and are formed on interaction of metals, hydrides, or alkyls, MR , with alcohols. The cubane-shaped NaORp molecules of this kind are present not only in the solid state but even in gas. The temperatures of their sublimation decrease on substitution for Me and H with CF3-groups. The stability of the Na...F bonds is so high that the gas-phase decomposition of these compounds ( 300°C) yields NaF [1386]. The observed frequency corresponding to the vibration of the C-O bonds in... [Pg.198]

The main route to rhenium alkoxides is the interaction of halids and oxy-halids with alkali alkoxides or alcohols in presence of amines (method 5). As the important starting reagents can serve also Re2(CO),0 and Re207 (method 3) The preparation ofrhenium (V) and (VI) oxoderivatives by the anodic oxidation of metal in alcohols has also been described (method 2) (see Table 12.22). The bimetallic alkoxides ofrhenium and heavy transition metals can most efficiently be obtained by interaction ofrhenium (VII) oxide with the alkoxides ofthese elements in refluxing toluene ... [Pg.473]

The nitro group has various coordination modes [7,78-81], Synthesis of complexes of metal nitrates is carried out, in the majority of cases, by the method of immediate interaction of these salts with ligands in aqueous-organic (mainly, alcohols) media. Also, the interactions of metal oxides, ligands, and nitric acid are applied, for example (4.18) [82,83], The structure of mixed-ligand complex 848, containing chelate NOT - group, was proved by x-ray diffraction [82,83],... [Pg.329]

The production process of dibutyltindibromide is based on the interaction of butylbromide with metallic tin at 85-90 °C in the presence of activating additives (butyl alcohol or water) and under the influence of ionising y-radiation ... [Pg.402]

Alcohol decomposition does provide additional insight into the interaction of adsorbates with metal oxide surfaces. The reactions of alkoxides on titanium dioxide have been used to probe thermal and photo-reactivity of powder and single crystal samples. [Pg.424]

Both types of catalysts have been successfully used for the hydrogenation of acrolein and acetophenone to improve the selectivity to allyl alcohol and phenylethanol, respectively [19]. Finally, it could be possible too, that the interaction of Ag with lanthanum or manganese oxides may result in a modification of the electronic environment of Ag because of the electron donation properties brought about their basicities. Therefore, in-situ XPS measurements are currently performed to assess the oxidation state of the metals in the working catalyts. [Pg.287]


See other pages where Interaction of Metals with Alcohols is mentioned: [Pg.14]    [Pg.200]    [Pg.209]    [Pg.14]    [Pg.200]    [Pg.209]    [Pg.112]    [Pg.117]    [Pg.259]    [Pg.369]    [Pg.196]    [Pg.232]    [Pg.4]    [Pg.749]    [Pg.59]    [Pg.21]    [Pg.166]    [Pg.167]    [Pg.245]    [Pg.66]    [Pg.408]    [Pg.253]    [Pg.749]    [Pg.310]    [Pg.205]    [Pg.144]    [Pg.68]    [Pg.263]    [Pg.779]    [Pg.196]    [Pg.198]    [Pg.243]    [Pg.18]    [Pg.35]    [Pg.662]   


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