Metals reactions with alcohols

From Metal Halides. The reaction of metal chlorides with alcohols can give metal chloride alkoxides (67—69), eg... 

The ionic P-P bond polarization renders P-phosphino-NHPs highly active reactants for various metathesis and addition reactions at exceedingly mild conditions. Metathesis is observed in reactions with alcohols, chloroalkanes, and complex transition metal halides (Schemes 11 and 12) [39, 73], Of particular interest are the reactions with chlorotrimethylstannane which yield equilibria that are driven by a subtle balance of P-X bond strengths to yield either diphosphines or P-chloro-NHPs as preferred product (Scheme 11). Chlorotrimethylsilane does not react with... 

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. 

Carbamates have been prepared by heating ethyl carbamate with a higherboiling alcohol in the presence or absence of catalysts [31-33], Aluminum iso-propoxide has been reported [34] to be an excellent catalyst for the interchange reaction between ethyl carbamate and benzyl alcohol. The interchange reaction is also effective for /V-alkyl carbamates as well as unsubstituted carbamates [35]. This catalyst is effective in preparing mono- and dicarbamates in excellent yields from primary and secondary alcohols and diols. Other effective catalysts are dibutyltin dilaurate [36], dibutyltin oxide [37], sulfuric acid or p-toluenesulfonic acid [31], and sodium metal (reacts with alcohols to give the alkoxide catalyst) [33]. 

Platinum(II)15 and palladium(II)16 complexes of phosphorus trichloride undergo solvolysis in water and alcohols to form complexes with orthophosphorous acid or orthophosphite ligands (equation 6). Similar reactions occur between the palladium(II) phenyldichlorophosphine complex (8) and the diols ethyleneglycol and catechol, but new chelate rings are not formed (Scheme 2). Solvolysis also occurs with attack of diphenylphosphinic acid or a similar diphenylchlorophosphine complex (9) (equation 7). The palladium complexes (8) and (9) are unstable to excess methanol, water or base and undergo reduction. Similarly, the phosphorus trichloride gold(I) complex (10) is reduced by water, but forms stable products on reaction with alcohols (equation 8).15 During the above reactions, the phosphorus—metal bond remains intact and the overall process is one of substitution at phosphorus. 

By Reactions of Metal Dialkylamides with Alcohols and Phenols 339... 

From Metal Alkyls and Hydrides 15.3.2.6.1 By reactions with alcohols or phenols... 

Direct evidence for a mechanism involving a single mode of chain growth as depicted in Scheme 1 came from our studies on the copolymerization reaction in alcoholic solvents35). The mechanism, as outlined in Scheme 1, involves the formation of Pd-acyl species as intermediates at every other step in the propagation sequence. Since the formation of esters through the reaction of transition metal-acyls with alcohols is well-precedented, it should be possible to intercept the propagation sequence if the polymerization was carried out in the presence of alcohols, Eq. (13). 

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 ... 

Nearly all the methods described in Chapter 2 have been applied for the preparation of uranium derivatives. The reaction of metallic uranium with alcohols in the presence of halogenes (method 1) doesn t lead, as it turned out, to homoleptic alkoxides, but is a facile route to alkoxide halides [79, 1669] ... 

L. Vaska and J. W. DiLuzio, On the origin of hydrogen in metal hydride complexes formed by reaction with alcohols, J. Am. Chem. Soc., 8 (1962) 4989 1990. 

Selenium tetrafluoride, which can be prepared from selenium metal and chlorine trifluoridc (CIF3), was introduced by Olah as a fluorinating agent for carbonyl compounds and alcoholsT It is generally necessary to add pyridine in the reactions with alcohols I. Pyridine forms a I 1 complex with selenium tetrafluoride and neutralizes the hydrogen fluoride which is formed in the fluorination reaction. 

The reaction between MPhCl(CO)(PPh3)2 species and CI3 Sift also gives metal complexes. They undergo substitution reactions with alcohols and alkyllithium reagents to give SiR3 species (Scheme 69). ... 

Metal alkoxides M(OR), where R is typically an alkyl group (R = Me, Et, etc ), have been known for a long time. Many of them (M = Si, Al, Ti, etc.) are now coimnercially available. They can be synthesized via the reaction of metal chlorides with alcohol as follows ... 

The reaction of metal chloride with alcohol is not the only way to synthesize alkoxides. Other inorganic compounds such as oxides can also be used as precursors for the synthesis of metal alkoxides ... 

Typical reactions of CS2 are summarized in Figure 42. CS2 forms a range of metal complexes,making use of one, two, or all of its atoms (Figure 43). Commercially, the reaction with alcohol (cellulose) is used in the manufacture of viscose fiber this use, together with the preparation of CCI4, accounts for the majority of CS2 manufacture, with lesser... 

A variant of direct metallation, cocondensation, has been utilized to prepare the first <7-bonded organocalcium complex, (SiMe3)2CH 2Ca(l,4dioxane)2, in addition to a transient heteroleptic calcium hydride, CeHsCaH by C-H activation (equation 3). The heteroleptic hydride is highly reactive and decomposes upon warming the reaction vessel above —78 °C. The product has been identified by its reaction with alcohols, affording quantitatively a series of calcium aryloxides. 

Alkoxycarbonyl Complexes by Reaction of Metal Carbonyls with Alcohols and Alkoxides. 

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