Ammonium salts of acids

Since, as has been described above, amides can be obtained by removal of water from the ammonium salts of acids, nitriles can be prepared directly from ammonium salts in one operation by heating them with a powerful dehydrating agent, e.g. ammonium acetate with P205 ... 

Haga, T. Crosby, K. E. Schussler, J. R. (Poly)ethereal ammonium salts of acidic herbicides and theii use as herbicides. US Patent 6300323, 2001 Chem. Abstr. 2001, 135, 284542. 

Primary amides have the general formula RCONH2. They can be prepared by the reaction of ammonia with esters (eq. 10.24), with acyl halides (eq. 10.36), or with acid anhydrides (eq. 10.39). Amides can also be prepared by heating the ammonium salts of acids. 

Ammonium salts of acids amides of carboxylic and simple sulphonic acids imides aldehyde-ammonias urea, its salts and monosubstitution products many ortho and para aromatic nitro-amines oximes car-bazides nitriles (some feebly) guanidines tMoureaand its mono-substitution products purines (e.g. uric acid). 

Ammonium salt of any acid Acid amides Acid nitriles Imides of dibasic acids... 

Note. For a very weak acid, the ammonium salt of which may dissociate rapidly on heating, conversion into the sodium salt rs recommended. Place o-1 g. of the acid in a boiling-tube and add NaOH solution until the mixture is just alkaline to litmus-paper. Add dil. HNO3 until just acid and then a slight excess of ammonia until again just alkaline. Add a piece of unglazed porcelain, and boil until the odour of ammonia is removed, and then cool. 

A) AMMONIUM SALTS. R COONH4. Ammonium salts of formicy acetic oxalic, succinic, tartaric, citric acid benzoic, salicylic (and other substituted benzoic acids) phthalic and cinnamic acids. 

A) Adds. The ammonium salts of aromatic acids when acidified in cold aqueous solution will deposit the crystalline acid. 

The above method of preparing a neutral solution of the ammonium salt cannot be applied to extremely weak acids (e.g., some amino-acids), the ammonium salts of which dissociate in boiling aqueous solution. 

By the dehydration of the ammonium salt of the corresponding acid by heat or by distillation, for example ... 

I ole is obtained by distilling the ammonium salt of muclc acid, preferably in the presence of glycerol which leads to an improved yield CHOHCHOHCOONH4 CH=CH ... 

When acetone is condensed with ethyl cyanoacetate in the presence of a solution of anhydrous ammonia in absolute alcohol at —5°, the ammonium salt of the dicyano-imlde (I) is precipitated. Upon dissolving this salt in water and adding excess of concentrated hydrochloric acid, the crystalline dicyano-imide (II) is obtained. Hydrolysis of the last-named with strong sulphuric acid affords p p dimethylglutaric acid (III). 

When an alkyl aryl ketone is heated with yellow ammonium polysulphide solution at an elevated temperature, an aryl substituted aliphatic acid amide is foimed the product actually isolated is the amide of the ci-aryl carboxylic acid together with a smaller amount of the corresponding ammonium salt of the oarboxylio acid. Thus acetophenone affords phenylacetamide (50 per cent.) and ammonium phenylacetate (13 per cent.) ... 

VII,10. AMMONIUM SALT OF AURIN TRICARBOXYLIC ACID ( ALUMINON )... 

Occasionally an optically inactive sample of tartaric acid was obtained Pasteur noticed that the sodium ammonium salt of optically inactive tartaric acid was a mixture of two mirror image crystal forms With microscope and tweezers Pasteur carefully sep arated the two He found that one kind of crystal (m aqueous solution) was dextrorota tory whereas the mirror image crystals rotated the plane of polarized light an equal amount but were levorotatory... 

Alnminon (qualitative test for aluminum). The reagent consists of 0.1% solution of the ammonium salt of aurin tricarboxylic acid. A bright red precipitate, persisting in alkaline solution, indicates aluminum. 

Moleculady mixed composites of montmorillonite clay and polyimide which have a higher resistance to gas permeation and a lower coefficient of thermal expansion than ordinary polyimides have been produced (60). These polyimide hybrids were synthesized using montmorillonite intercalated with the ammonium salt of dodecylamine. When polymerized in the presence of dimethyl acetamide and polyamic acid, the resulting dispersion was cast onto glass plates and cured. The cured films were as transparent as polyimide. 

For deliming, ammonium salts and acids are used. The proportion of ammonium salts to acids and the type of acids employed is a matter of the tanner s choice. The acid neutralizes the lime, Ca(OH)2, thereby adjusting the pH. The ammonium salts have two functions to buffer the solution to a pH required for bating, and to form calcium ammonium complexes. The acidity and the complex formation solubilize the calcium and serve to bring the hide to the desired pH. 

Orthophosphate salts are generally prepared by the partial or total neutralization of orthophosphoric acid. Phase equiUbrium diagrams are particularly usehil in identifying conditions for the preparation of particular phosphate salts. The solution properties of orthophosphate salts of monovalent cations are distincdy different from those of the polyvalent cations, the latter exhibiting incongment solubiUty in most cases. The commercial phosphates include alkah metal, alkaline-earth, heavy metal, mixed metal, and ammonium salts of phosphoric acid. Sodium phosphates are the most important, followed by calcium, ammonium, and potassium salts. 

These association reactions can be controlled. Acetone or acetonylacetone added to the solution of the polymeric electron acceptor prevents insolubilization, which takes place immediately upon the removal of the ketone. A second method of insolubiUzation control consists of blocking the carboxyl groups with inorganic cations, ie, the formation of the sodium or ammonium salt of poly(acryhc acid). Mixtures of poly(ethylene oxide) solutions with solutions of such salts can be precipitated by acidification. 

Inositols, ie, hexaliydrobenzenehexols, are sugars that have received increasing study and are useful in the treatment of a wide variety of human disorders, including vascular disease, cancer, cirrhosis of the Hver, frostbite, and muscular dystrophy (269). Myoinositol esters prepared by reaction with lower fatty acid anhydrides are useful as Hver medicines and nonionic surfactants the aluminum and ammonium salts of inositol hexasulfate are useful anticancer agents (270). Tetraarjloxybenzoquinones are intermediates in the preparation of dioxazine dyes (266,271). The synthesis of hexakis(aryloxy)benzenes has also beenpubUshed (272). 

Aqueous solutions of ammonium haUdes, like the other ammonium salts of strong acids, are acidic on storage and exposure these solutions tend to become more acidic through ammonia loss. They also have a pronounced tendency to attack ferrous and other metal surfaces, especiaHy those of copper and copper aHoys. 

Decomposition and Detonation Hazard. Ammonium nitrate is considered a very stable salt, even though ammonium salts of strong acids generally lose ammonia and become slightly acidic on storage. For ammonium nitrate, endothermic dissociation from lowering pH occurs above 169°C. 

The most commonly used emulsifiers are sodium, potassium, or ammonium salts of oleic acid, stearic acid, or rosin acids, or disproportionate rosin acids, either singly or in mixture. An aLkylsulfate or aLkylarenesulfonate can also be used or be present as a stabilizer. A useful stabilizer of this class is the condensation product of formaldehyde with the sodium salt of P-naphthalenesulfonic acid. AH these primary emulsifiers and stabilizers are anionic and on adsorption they confer a negative charge to the polymer particles. Latices stabilized with cationic or nonionic surfactants have been developed for special apphcations. Despite the high concentration of emulsifiers in most synthetic latices, only a small proportion is present in the aqueous phase nearly all of it is adsorbed on the polymer particles. 

The formation of amides can be accompHshed by dehydration of the ammonium salts of sahcyhc acid. The more common method for amines is the reaction of the ester, acyl hahde, or anhydride with an amine or ammonia. Each step is fast and essentially irreversible. 

Polypeptide Synthesis and Analysis. Sihca or controUed-pore glass supports treated with (chloromethyl)phenylethyltrimethoxysilane [68128-25-6] or its derivatives are replacing chloromethylated styrene—divinylbenzene (Merrifield resin) as supports in polypeptide synthesis. The sdylated support reacts with the triethyl ammonium salt of a protected amino acid. Once the initial amino acid residue has been coupled to the support, a variety of peptide synthesis methods can be used (34). At the completion of synthesis, the anchored peptide is separated from the support with hydrogen bromide in acetic acid (see Protein engineering Proteins). 

Amides react ia certain cases to form ammonium salts of sulfonated amides (22). For example, treatment with ben2amide yields ammonium A/-ben2oylsulfamate [83930-12-5] C H CONHSO NH, and treatment with ammonium sulfamate yields dianmioiiiumimidodisulfonate [13597-84-17, HN(S020NH 2 Ammonium sulfamate or sulfamic acid and ammonium carbonate dehydrate Hquid or soHd amides to nitriles (27). 

TYZOR LA [65104-06-5] (5), an aqueous solution of the ammonium salt of the titanium bis-lactate complex, is prepared from two equivalents of lactic acid to one of TYZOR TPT. The by-product isopropyl alcohol is removed by distillation and the resultant solution is neutralized with ammonium hydroxide. 

The ammonium salts of vanadic acid and vanadium pentoxide have been Hsted as toxic constituents in soHd wastes under the Resource Conservation and Recovery Act (27). 

Caibon disulfide reacts with piimaiy and secondary amines to yield substituted ammonium salts of N-substituted dithiocarbamic acids, RNHC(S)SNH3R and R2NC(S)SNH2R2 ... 

Copper—Liquor Scrubbing. Cuprous ammonium salts of organic acids form complexes with carbon monoxide. 

Uninhibited chloroprene suitable for polymerisation must be stored at low temperature (<10° C) under nitrogen if quaUty is to be maintained. Otherwise, dimers or oxidation products are formed and polymerisation activity is unpredictable. Insoluble, autocatalytic "popcorn" polymer can also be formed at ambient or higher temperature without adequate inhibition. For longer term storage, inhibition is required. Phenothiasine [92-84-2] / fZ-butylcatechol [2743-78-17, picric acid [88-89-17, and the ammonium salt of /V-nitroso-/V-pheny1hydroxy1 amine [135-20-6] have been recommended. 

Reactions of the Side Chain. Benzyl chloride is hydrolyzed slowly by boiling water and more rapidly at elevated temperature and pressure in the presence of alkaHes (11). Reaction with aqueous sodium cyanide, preferably in the presence of a quaternary ammonium chloride, produces phenylacetonitrile [140-29-4] in high yield (12). The presence of a lower molecular-weight alcohol gives faster rates and higher yields. In the presence of suitable catalysts benzyl chloride reacts with carbon monoxide to produce phenylacetic acid [103-82-2] (13—15). With different catalyst systems in the presence of calcium hydroxide, double carbonylation to phenylpymvic acid [156-06-9] occurs (16). Benzyl esters are formed by heating benzyl chloride with the sodium salts of acids benzyl ethers by reaction with sodium alkoxides. The ease of ether formation is improved by the use of phase-transfer catalysts (17) (see Catalysis, phase-thansfer). 

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