Ammonium acetate salts

The clear solution, obtained by centrifuging a solution of the oxide in aqueous ammonia which had been treated with silver nitrate until precipitation started, exploded on two occasions after 10-14 days storage in closed bottles in the dark. This was ascribed to slow precipitation of amorphous silver imide, which is very explosive even when wet [1], When silver oxide is dissolved in ammonia solution, an extremely explosive precipitate (probably Ag3N4) will separate. The explosive behaviour is completely inhibited by presence of colloids or ammonium salts (acetate, carbonate, citrate or oxalate). Substitution of methylamine for ammonia does not give explosive materials [2],... 

Acetic Acid, Ammonium Salt Acetic Acid, Butyl Ester Acetic Acid, Cupric Salt Acetic Acid, Dimethylamide Acetic Acid, Ethyl Ester Acetic Acid, Isobutyl Ester Acetic Acid, Isopropyl Ester Acetic Acid, Methyl Ester Acetic Acid, Nickel (II) Salt Acetic Acid, Propyl Ester Acetic Acid, Sec-Butyl Ester Acetic Acid, Zinc Salt Acetic Aldehyde Acetic Anhydride Acetic Ester Acetic Ether... 

Other researchers [50] deal that the use acid-base catalyst (ammonium salts acetates and trifluoroacetates of diethylammonium, morpholinimn, piperidinimn) promotes the creation of the Knoevenagel-Cope condensation product (X,P-imsaturated nitrile) and enhances the yield of final 2-aminothiophene. Ionic liquids used as solvents in combination with ethylenediammonium diacetate were shown to be very efficient in the case of the Gewald synthesis with aliphatic and alicyclic ketones with possibility of regeneration of used liquids [83]. 

Dehydration of the corresponding ammonium salt. Thus ammonium acetate on heating loses water giving acetamide. An excess of acetic acid is... 

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. 

Phosphorylated cottons are flame resistant ia the form of the free acid or the ammonium salt. Siace these fabrics have ion-exchange properties, conversion to the sodium salt takes place readily during laundering if basic tap water is used. However, flame resistance can be restored if the fabric is treated with either acetic acid [1563-80-8] or ammonium hydroxide [1336-21 -6] after washing. 

The compound can be prepared from 2,4,6-trinitrophenol (picric acid [88-89-1]) by reduction with sodium hydrosulfide (163), with ammonia —hydrogen sulfide followed by acetic acid neutralization of the ammonium salt (164), with ethanolic hydrazine and copper (165), or electrolyticaHy with vanadium sulfate in alcoholic sulfuric acid (159). Heating 4,6-dinitro-2-benzamidophenol in concentrated HQ. at 140°C also yields picramic acid (166). 

Carbonyl Compounds. Cychc ketals and acetals (dioxolanes) are produced from reaction of propylene oxide with ketones and aldehydes, respectively. Suitable catalysts iaclude stannic chloride, quaternary ammonium salts, glycol sulphites, and molybdenum acetyl acetonate or naphthenate (89—91). Lactones come from Ph4Sbl-cataly2ed reaction with ketenes (92). 

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). 

Physical Properties. Sulfuryl chloride [7791-25-5] SO2CI2, is a colorless to light yellow Hquid with a pungent odor. Physical and thermodynamic properties are Hsted ia Table 7. Sulfuryl chloride dissolves sulfur dioxide, bromine, iodine, and ferric chloride. Various quaternary alkyl ammonium salts dissolve ia sulfuryl chloride to produce highly conductive solutions. Sulfuryl chloride is miscible with acetic acid and ether but not with hexane (193,194). 

Strong bases, such as potassium acetate, potassium 2-ethylhexoate, or amine—epoxide combinations are the most useful trimerization catalysts. Also, some special tertiary amines, such as 2,4,6-tns(A7,A7-dimethylarninomethyl)phenol (DMT-30) (6), l,3,5-tris(3-dimethylaminopropyl)hexahydro-j -triazine (7), and ammonium salts (Dabco TMR) (8) are good trimerization catalysts. 

L-Tyrosine [60-18-4] M 181.2, m 290-295 (dec), [aj -10.0 (5M HCl), pK 2.18 (CO2H), pK2 9.21 (OH), pK 3 10.47 (NH2). Likely impurities are L-cysteine and the ammonium salt. Dissolved in dilute ammonia, then crystd by adding dilute acetic acid to pH 5. Also crystd from water or EtOH/water, and dried at room temperature under vacuum over P2O5. 

Ammonium nitrate and other ammonium salts Any oxidizable substance, such as ethanol, methanol, glacial acetic acid, acetic anhydride, benzaldehyde, carbon disulphide, glycerol, ethylene glycol, ethyl acetate, methyl acetate or furfural Chlorates, perchlorates, permanganates... 

The isocyanurate reaction occurs when three equivalents of isocyanate react to form a six-membered ring, as shown in the fifth item of Fig. 1. Isocyanurate linkages are usually more stable than urethane linkages. Model compound studies show no degradation of the trimer of phenyl isocyanate below 270°C [10,11]. Catalysts are usually needed to form the isocyanurate bond. Alkali metals of carboxylic acids, such as potassium acetate, various quaternary ammonium salts, and even potassium or sodium hydroxide, are most commonly used as catalysts for the isocyanurate reaction. However, many others will work as well [12]. 

A suspension of 40 g 3-acetylaminomethyl-5-amino-2,4,6-triodobenzoic acid in 180 ml acetic anhydride were mixed with 0.4 ml concentrated sulfuric acid. An exothermic reaction was thereby initiated. Acetylation was completed by heating to 80°C for three hours. The reaction mixture was then evaporated to dryness in a vacuum at a temperature not exceeding 50°C. The residue was treated with a mixture of 30 ml concentrated aqueous ammonium hydroxide and 40 ml water, whereby the solid material dissolved with spontaneous heating. Within a few minutes, the ammonium salt of the acetylated product started precipitating. The precipitate and residual liquid were cooled externally with ice after about 15 minutes. The salt was separated from the liquid by filtration with suction, and was washed with ice cold saturated ammonium chloride solution. 

The precipitate is soluble in free mineral acids (even as little as is liberated by reaction in neutral solution), in solutions containing more than 50 per cent of ethanol by volume, in hot water (0.6 mg per 100 mL), and in concentrated ammoniacal solutions of cobalt salts, but is insoluble in dilute ammonia solution, in solutions of ammonium salts, and in dilute acetic (ethanoic) acid-sodium acetate solutions. Large amounts of aqueous ammonia and of cobalt, zinc, or copper retard the precipitation extra reagent must be added, for these elements consume dimethylglyoxime to form various soluble compounds. Better results are obtained in the presence of cobalt, manganese, or zinc by adding sodium or ammonium acetate to precipitate the complex iron(III), aluminium, and chromium(III) must, however, be absent. 

Weak acids with weak bases. The titration of a weak acid and a weak base can be readily carried out, and frequently it is preferable to employ this procedure rather than use a strong base. Curve (c) in Fig. 13.2 is the titration curve of 0.003 M acetic acid with 0.0973 M aqueous ammonia solution. The neutralisation curve up to the equivalence point is similar to that obtained with sodium hydroxide solution, since both sodium and ammonium acetates are strong electrolytes after the equivalence point an excess of aqueous ammonia solution has little effect upon the conductance, as its dissociation is depressed by the ammonium salt present in the solution. The advantages over the use of strong alkali are that the end point is easier to detect, and in dilute solution the influence of carbon dioxide may be neglected. 

Another application of this method is the stereoselective addition of (7 )-2-hydroxy-l,2,2-triphenylethyl acetate, via the lithium enolate, to propenal (acrolein) which affords mainly the ester 13 (d.r. 92 8). When the acid, obtained in the subsequent alkaline hydrolysis, is converted into the ammonium salt derived from (.S)-l -phenylethylaminc, and the salt recrystallized once, then the amine liberated (/f)-3-hydroxy-4-pentenoic acid is obtained in 41 % yield [relative to the (/ )-acetate] and >99.8% ee82. 

The peak capacity is not pertinent as the separation was developed by a solvent program. The expected efficiency of the column when operated at the optimum velocity would be about 5,500 theoretical plates. This is not a particularly high efficiency and so the separation depended heavily on the phases selected and the gradient employed. The separation was achieved by a complex mixture of ionic and dispersive interactions between the solutes and the stationary phase and ionic, polar and dispersive forces between the solutes and the mobile phase. The initial solvent was a 1% acetic acid and 1 mM tetrabutyl ammonium phosphate buffered to a pH of 2.8. Initially the tetrabutyl ammonium salt would be adsorbed strongly on the reverse phase and thus acted as an adsorbed ion exchanger. During the program, acetonitrile was added to the solvent and initially this increased the dispersive interactions between the solute and the mobile phase. 

Another catalytic system which has been successfully applied to the autoxidation of substituted toluenes involves the combination of Co/Br" with a quaternary ammonium salt as a phase transfer catalyst (ref. 20). For example, cobalt(II) chloride in combination with certain tetraalkylammonium bromides or tetraalkylphosphonium bromides afforded benzoic acid in 92 % yield from toluene at 135-160 °C and 15 bar (Fig. 19). It should be noted that this system does not require the use of acetic acid as solvent. The function of the phase transfer catalyst is presumably to solubilize the cobalt in the ArCH3 solvent via the formation of Q + [CoBr]. ... 

This is an Sn2 process, since inversion is found at R. Another good leaving group is NTS2 ditosylamines react quite well with acetate ion in dipolar aprotic solvents RNTs2 4- OAc — ROAc. Ordinary primary amines have been converted to acetates and benzoates by the Katritzky pyrylium-pyridinium method (p. 447). Quaternary ammonium salts can be cleaved by heating with AcO in an aprotic solvent. Oxonium ions can also be used as substrates RsO -f R COO —> R COOR R2O. 

Even though formic anhydride is not a stable compound (see p. 714), amines can be formylated with the mixed anhydride of acetic and formic acids (HCOO-COMe) °°° or with a mixture of formic acid and acetic anhydride. Acetamides are not formed with these reagents. Secondary amines can be acylated in the presence of a primary amine by conversion to their salts and addition of 18-crown-6. ° The crown ether complexes the primary ammonium salt, preventing its acylation, while the secondary ammonium salts, which do not fit easily into the cavity, are free to be acylated. 

Alternatively, the reaction of 93c (R = n-Bu) with ammonium thiocyanate in refluxing acetic acid gave the ammonium salt of N-phosphonomethylthiohydantoin 99 in moderate isolated yield (2). 

Rather than preforming the a-amino ketimines to be reduced, it is often advantageous to form in situ the more reactive iminium ions from a-aminoketones and primary amines or ammonium salts in the presence of the reducing agent, e.g., sodium cyanoborohydride. Use of this procedure (reductive amination) with the enantiopure a-aminoketone 214 and benzylamine allowed the preparation of the syn diamines 215 with high yields and (almost) complete diastereoselectivities [100] (Scheme 32). Then, the primary diamines 216 were obtained by routine N-debenzylation. Similarly, the diamine 217 was prepared using ammonium acetate. In... 

Potassium or ammonium salts of peroxydisulphonic acid with acetic acid. 

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