Chemical Hydrides Hydrolysis

R. Aiello, J.H. Sharp, M.A. Matthews, Production of hydrogen from chemical hydrides via hydrolysis with steam , Int. J. Hydrogen Energ. 24 (1999) 1123-1130. 

Hydrolysis reactions involve the oxidation reaction of chemical hydrides with water to produce hydrogen. The reaction of sodium borohydride has been the most studied to date ... 

Hydrolysis reactions involve the oxidation reaction of chemical hydrides with water to produce hydrogen. The reaction of sodium borohydride has been the most studied to date. In the first embodiment, a slurry of an inert stabilizing liquid protects the hydride from contact with moisture and makes the hydride pumpable. At the point of use, the slurry is... 

Chemical Hydrides Chemical hydrides are manufactured hydrogen-containing materials that are chemically reacted with water, releasing heat and hydrogen gas. The hydrogen release process occurs upon a hydrolysis reaction with water. For example, the sodium borohydride reaction is [9]... 

Another aspect of the hydrolysis of hydrides is the alkalinity that results, especially from alkaU metal and alkaline-earth hydrides. This alkalinity can cause chemical bums in skin and other tissues. Affected skin areas should be flooded with copious amounts of water. 

Hardness on the Mohs scale is often above 8 and sometimes approaches 10 (diamond). These properties commend nitrides for use as crucibles, high-temperature reaction vessels, thermocouple sheaths and related applications. Several metal nitrides are also used as heterogeneous catalysts, notably the iron nitrides in the Fischer-Tropsch hydriding of carbonyls. Few chemical reactions of metal nitrides have been studied the most characteristic (often extremely slow but occasionally rapid) is hydrolysis to give ammonia or nitrogen ... 

Compared to the lithium enolates of l and 5, the higher stereoselectivity obtained by the Mukaiyama variation is, in general, accompanied by reduced chemical yields. The chiral alcoholic moieties of the esters 3 and 7 can be removed either by reduction with lithium aluminum hydride (after protection of the earbinol group) or by aqueous alkaline hydrolysis with lithium hydroxide to afford the corresponding carboxylic acid. In both cases, the chiral auxiliary reagent can be recovered. 

Although geneologically related to indoles, the dihydroindoles behave chemically rather like alkyl anilines. When diphenylamine reacts with chloro-propionyl chloride, amide 40 results this in turn readily cyclizes to oxindole 41. Sodium hydride followed by 2-chloroethyldimethylamine alkylates the 3-position (possibly through an intermediate aziridinium ion) partial demethylation is accomplished by refluxing with ethylchiorocarbonate, followed by hydrolysis of the intermediate carbamate to give indolinone 42, the antidepressant amedalin Repetition of this sequence on the chloropropyl homologue, followed by reduction of the appropriate indolinone produces dihydroindole 43, daledalin, which also has antidepressant activity. ... 

Basic hydrolysis of 6 afforded alcohol 19 and methyl veratrate. The H-NMR spectrum of 19 (Table II) revealed the presence of one methylenedioxy, one N-methyl, and two methoxyl groups. The mass spectrum (Table IV) exhibited the most abundant and significant ion peak at m/z 229 indicative of metaphanine-type cleavage. Treatment of an aqueous THF solution of stephavanine (18) with excess sodium hydride and methyl iodide gave N.O-dimethylstephine, a compound identical to alcohol 19. Thus, the structure of the new alkaloid 6 was established by chemical correlation with stephavanine (79). 

As mentioned above, partial sintering of the metal is observed on silica during the hydrogen treatment. These hydrides have been partially characterized, in particular by H/D exchange, hydrolysis or chemical reactivity with CH3I or methane (Figure 2.13). 

On treatment with sodium bis (2-methoxyethoxy)aluminium hydride (Scheme 16), 122 gave the aldehyde 123, which was converted by standard synthetic operations, into the methyl-O-benzylester 124. Acid hydrolysis of 124 followed by allylic epoxidation of the diol furnished the p-oxirane 125. On heating 125 in water containing sodium benzoate a remarkable chain of chemical events took place that resulted in the generation of (+)-pancratistatin (94) in 2% overall yield starting from bromobenzene. 

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