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Hydrolysis with ammonia

Ammonolysis. Reactions involving ammonia. Ammonolysis of esters, acyl chlorides, and anhydrides give amides aniline is produced by ammonolysis of chlorobenzene. The reaction is analogous to hydrolysis, with ammonia substituted for water. [Pg.390]

When the base is liberated from the solution after hydrolysis with ammonia instead of sodium carbonate a dimolecular base bis-des-methylsinomenylidine is obtained instead of sinomenine hydrate [23], and this base is also obtained by the action of ammonia on the latter [61]. It is believed to arise from the self-condensation of the diketone, the carbonyl group at C-6 in each molecule condensing with the active methylene group at C-8 in the other, and the product is in fact a quinone. The structure of the product is shown in essence in [lxix]. The condensation of sinomeninone to bis-desmethylsinomenylidene is analogous to the self-condensation of diacetyl to p-xylene quinone [62],... [Pg.348]

In the case of CA-g-PS the polystyrene homopol)nner was removed by extraction with toluene. The CA-g-PAN was soluble in DMF in which the PAN is also soluble. Therefore, the reaction product was subjected to mild hydrolysis with ammonia to hydrolize the acetate groups, which then rendered the graft polymer insoluble in DMF. The hydrolysis product was extracted with DMF to remove any PAN homopolymer, and the IR spectrum recorded (D, Fig. 3). [Pg.414]

They are formed by heating dibasic acids or their anhydrides with ammonia. The hydrogen atom of the NH group is acidic and can be replaced by a metal. Mild hydrolysis breaks the ring to give the half amide of the acid. See succinimide and phthalimide. [Pg.214]

In the Strecker synthesis an aldehyde is converted to an a ammo acid with one more carbon atom by a two stage procedure m which an a ammo nitrile is an mterme diate The a ammo nitrile is formed by reaction of the aldehyde with ammonia or an ammonium salt and a source of cyanide ion Hydrolysis of the nitrile group to a car boxylic acid function completes the synthesis... [Pg.1121]

For most crops, other than rice, urea in the soil must first undergo hydrolysis to ammonia and then nitrification to nitrate before it can be absorbed by plant roots. One problem is that in relatively cool climates these processes are slow thus plants may be slow to respond to urea fertilization. Another problem, more likely in warmer climates, is that ammonia formed in the soil hydrolysis step may be lost as vapor. This problem is particularly likely when surface appHcation is used, but can be avoided by incorporation of the urea under the soil surface. Another problem that has been encountered with urea is phytotoxicity, the poisoning of seed by contact with the ammonia released during urea hydrolysis in the soil. Placement of urea away from the seed is a solution to this problem. In view of the growing popularity of urea, it appears that its favorable characteristics outweigh the extra care requited in its use. [Pg.220]

CeUulosic materials, such as farm wastes, can be upgraded for animal feed by simply bringing them into contact with ammonia (qv). The ceUulose sweUs and is made more digestible, and at the same time some ammonia nitrogen, which is a nutrient for mminants, is left behind. Supercritical ammonia improves susceptibiHty to enzymatic hydrolysis (17). [Pg.449]

Pyridazinecarboxamides are prepared from the corresponding esters or acid chlorides with ammonia or amines or by partial hydrolysis of cyanopyridazines. Pyridazinecarboxamides with a variety of substituents are easily dehydrated to nitriles with phosphorus oxychloride and are converted into the corresponding acids by acid or alkaline hydrolysis. They undergo Hofmann degradation to give the corresponding amines, while in the case of two ortho carboxamide groups pyrimidopyridazines are formed. [Pg.33]

Supercritical fluid solvents have been tested for reactive extractions of liquid and gaseous fuels from heavy oils, coal, oil shale, and biomass. In some cases the solvent participates in the reactions, as in the hydrolysis of coal and heavy oils with water. Related applications include conversion of cellulose to glucose in water, dehgnincation of wood with ammonia, and liquefaction of lignin in water. [Pg.2005]

Sulfobenzyl esters were prepared (cesium salt or dicyclohexylammonium salt, Na03SC6H4CH2Br, DMF, 37-95% yield) from A -protected amino acids. They are cleaved by hydrogenolysis (H2/Pd), or hydrolysis (NaOH, dioxane/water). Treatment with ammonia-or hydrazine results in formation of the amide or hydrazide. The ester is stable to 2 M HBr/AcOH and to CF3SO3H in CF3CO2H. The relative rates of hydrolysis and hydrazinolysis for different esters are as follows ... [Pg.259]

Glycine ethyl ester hydrochloride has been prepared by the action of absolute alcohol and hydrogen chloride on glycine from glycyl chloride and alcohol by the action of ammonia or hexamethylenetetramine on chloroacetic acid, and subsequent hydrolysis with alcoholic hydrochloric acid and by the action of hydrogen chloride and alcohol on methyleneamino-acetonitrile. ... [Pg.47]

Cellobiose was prepared first by Skraup and Konig by the saponification of the octaacetate with alcoholic potassium hydroxide, and the method was improved by Pringsheim and Merkatz.3 Aqueous barium hydroxide also has been employed for the purpose, and methyl alcoholic ammonia has been used extensively for the hydrolysis of carbohydrate acetates. The method of catalytic hydrolysis with a small quantity of sodium methylate was introduced by Zemplen,i who considered the action to be due to the addition of the reagent to the ester-carbonyl groups of the sugar acetate and the decomposition of the addition compound by reaction with alcohol. The present procedure, reported by Zemplen, Gerecs, and Hadacsy, is a considerable improvement over the original method (see Note 2). [Pg.35]

In one process the resulting solution is continuously withdrawn and cooled rapidly to below 75°C to prevent hydrolysis and then further cooled before being neutralised with ammonia. After phase separation, the oil phase is then treated with trichlorethylene to extract the caprolactam, which is then steam distilled. Pure caprolactam has a boiling point of 120°C at 10 mmHg pressure. In the above process 5.1 tons of ammonium sulphate are produced as a by-product per ton of caprolactam. [Pg.483]

Cracking of the ester at about 500°C leads to the formation of the undecylenic acid ester together with such products as heptyl alcohol, heptanoic acid and heptaldehyde. Undecylenic acid may then be obtained by hydrolysis of the ester. Treatment of the acid by HBr in the presence of a peroxide leads to w-bromoundecanoic acid together with the 10-isomer, which is removed. Treatment of the w-bromo derivative with ammonia leads to w-aminoundecanoic acid, which has a melting point of 50°C (Figure 18.8). [Pg.484]

When the reaction of S2CI2 with ammonia is carried out in a polar solvent, e.g., DMF, the hydrolysis of the reaction mixture with aqueous HCl produces a mixture of the cyclic sulfur imides S7NH, 1,3-, 1,4- and 1,5-S6(NH)2 and 1,3,5- and 1,3,6-S5(NH)3, which can be separated by chromatography on silica gel using CS2 as eluant (Section 6.2.1). °... [Pg.18]

The propionitrile (94) also yielded a pyrido[2,3-d]pyTimidine (96) when treated with ammonia or methylamine, the intermediate amidine (95) undergoing hydrolysis during the reaction.Amination was shown to be the rate-determining stage. [Pg.170]


See other pages where Hydrolysis with ammonia is mentioned: [Pg.4]    [Pg.71]    [Pg.71]    [Pg.273]    [Pg.49]    [Pg.4]    [Pg.49]    [Pg.74]    [Pg.21]    [Pg.4]    [Pg.71]    [Pg.71]    [Pg.273]    [Pg.49]    [Pg.4]    [Pg.49]    [Pg.74]    [Pg.21]    [Pg.28]    [Pg.193]    [Pg.312]    [Pg.410]    [Pg.115]    [Pg.307]    [Pg.251]    [Pg.383]    [Pg.218]    [Pg.273]    [Pg.394]    [Pg.154]    [Pg.291]    [Pg.589]    [Pg.752]    [Pg.5]    [Pg.45]    [Pg.112]    [Pg.406]    [Pg.230]    [Pg.372]    [Pg.389]    [Pg.391]   
See also in sourсe #XX -- [ Pg.457 , Pg.738 , Pg.739 ]

See also in sourсe #XX -- [ Pg.457 , Pg.738 , Pg.739 ]




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Hydrolysis with ammonia vapor

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