Metal hydroxides with alcohols

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. 

Alkali metal alkoxides and phenoxides may be obtained by reacting the metal hydroxide with either alcohol or phenol. With alcohols the generated water must be removed, typically as an azeotrope, as with sodium hydroxide dissolved in ethanol-benzene followed by reflux.69 With the more acidic phenols the phenoxides of Li, Na, K, Rb and Cs are more readily formed by simply heating MOH in absolute ethanol with phenol followed by recrystallization.70"72... 

Reactions of metal oxides or hydroxides with alcohols (method 3)... 

Reaction of tetraisopropyl titanate with an alkali or alkaline earth metal hydroxide in alcohol solution to form a soluble intermediate ... 

Reactions of Metal Oxides or Hydroxides with Alcohols (Method 1.3)... 

Formation of alkoxide complexes takes place on interaction of the most basic and the most acidic oxides/hydroxides with alcohols, due, most probably, to pro-tolytic catalysis. The most efficient turned to be in the synthesis of diol derivatives of the most acidic metal oxides - Re207 [115] and M0O3 [116] ... 

Difluoroethanol is prepared by the mercuric oxide cataly2ed hydrolysis of 2-bromo-l,l-difluoroethane with carboxyHc acid esters and alkaH metal hydroxides ia water (27). Its chemical reactions are similar to those of most alcohols. It can be oxidi2ed to difluoroacetic acid [381-73-7] (28) it forms alkoxides with alkaH and alkaline-earth metals (29) with alkoxides of other alcohols it forms mixed ethers such as 2,2-difluoroethyl methyl ether [461-57-4], bp 47°C, or 2,2-difluoroethyl ethyl ether [82907-09-3], bp 66°C (29). 2,2-Difluoroethyl difluoromethyl ether [32778-16-8], made from the alcohol and chlorodifluoromethane ia aqueous base, has been iavestigated as an inhalation anesthetic (30,31) as have several ethers made by addition of the alcohol to various fluoroalkenes (32,33). Methacrylate esters of the alcohol are useful as a sheathing material for polymers ia optical appHcations (34). The alcohol has also been reported to be useful as a working fluid ia heat pumps (35). The alcohol is available ia research quantities for ca 6/g (1992). 

The primary and secondary alcohol functionahties have different reactivities, as exemplified by the slower reaction rate for secondary hydroxyls in the formation of esters from acids and alcohols (8). 1,2-Propylene glycol undergoes most of the typical alcohol reactions, such as reaction with a free acid, acyl hahde, or acid anhydride to form an ester reaction with alkaU metal hydroxide to form metal salts and reaction with aldehydes or ketones to form acetals and ketals (9,10). The most important commercial appHcation of propylene glycol is in the manufacture of polyesters by reaction with a dibasic or polybasic acid. 

Alkali metal xanthates are prepared in high yield from reaction of amyl alcohols with alkah metal hydroxide and carbon disulfide (39—42). The xanthates are useful as collectors in the flotation of minerals and have minor uses in vulcani2ation of mbber and as herbicides (39,41). 

The alkah metal xanthates are generally prepared from the reaction of sodium or potassium hydroxide with an alcohol and carbon disulfide. The initial reaction is the formation of the alkoxide, which reacts with carbon disulfide to give the xanthate ... 

I) Refluxing said benzyl ester with an aqueous alcoholic alkali metal hydroxide solution to saponify the benzyl ester group, neutralizing the saponification mixture by the addition of hydrochloric acid, extracting the neutralized mixture with chloroform, and separating the resulting (S,N-ditrityl-L-cysteinyl)-L-proline. 

Benzohydrol has been obtained by reducing benzophenone with sodium amalgam,1 with metallic calcium and alcohol,2 with hydrogen in the presence of a catalyst,3 with zinc, aluminium or sodium in strongly alkaline solutions,4 with zinc dust and alcoholic potassium hydroxide solution,5 and electrolytically.6... 

The Ford hydroglycolysis process is an example of a combined approach for die depolymerization of PURs. In a reactor, polyurethane foam is reacted with a mixture of water, diethylene glycol, and alkali metal hydroxides at high temperature to form polyols. When sodium hydroxide is added as a catalyst, a cleaner polyol is formed because all of the carbamates and ureas in the product are converted into amines and alcohols by hydrolysis.33... 

A. H. Zuzich and G. C. Blytas. Polyethercyclicpolyols from epihalohy-drins, polyhydric alcohols and metal hydroxides or epoxy alcohol and optionally polyhydric alcohols with addition of epoxy resins. Patent US 5286882, 1994. 

The presence of three nitro groups on the aromatic ring of picryl chloride makes the chloro group extremely reactive towards nucleophiles. Picryl chloride (87) is hydrolyzed to picric acid (4) in the presence of hot water or aqueous sodium hydroxide. Aminolysis of picryl chloride in the presence of primary and secondary amines is complete in minutes at room temperature. Picryl chloride is therefore a very useful starting material for the synthesis of a range of other picryl derivatives. The reaction of picryl chloride (87) with ammonia can be used to synthesize 2,4,6-trinitroaniline (53) (picramide). Treatment of picryl chloride with alcohols under reflux forms picric acid and the alkyl chloride of the corresponding alcohol, whereas the same reaction in the presence of alkali metal hydroxides, or the alkoxide anion of... 

Lithium hydride and sodium hydride are the only alkali metal hydrides of much practical importance. They are useful when it is desirable for proton (or hydrogen atom) transfers to accompany electron-transfer events. Because these hydrides react quickly with water to form alkali metal hydroxides and hydrogen gas, they are frequently used as drying agents, particularly for hydrocarbons and ethers. Care should be exercised in using them to dry solvents that are not predried, and they should not be used to dry alcohols or halogenated solvents. 

Alkyl halides undergo Sn2 reactions with a variety of nucleophiles, e.g. metal hydroxides (NaOH or KOH), metal alkoxides (NaOR or KOR) or metal cyanides (NaCN or KCN), to produce alcohols, ethers or nitriles, respectively. They react with metal amides (NaNH2) or NH3, 1° amines and 2° amines to give 1°, 2° or 3° amines, respectively. Alkyl halides react with metal acetylides (R C=CNa), metal azides (NaN3) and metal carboxylate (R C02Na) to produce internal alkynes, azides and esters, respectively. Most of these transformations are limited to primary alkyl halides (see Section 5.5.2). Higher alkyl halides tend to react via elimination. 

We have already learnt that alkyl halides react with alcohols and metal hydroxide (NaOH or KOH) to give ethers and alcohols, respectively. Depending on the alkyl halides and the reaction conditions, both S l and Sn2 reactions can occur. Alkyl halides undergo a variety of transformation through Sn2 reactions with a wide range of nucleophiles (alkoxides, cyanides, acetylides, alkynides, amides and carboxylates) to produce other functional groups. 

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