Ammonium acetate bromide

Pashley R M, McGuiggan P M, Ninham B W, Brady J and Evans D F 1986 Direct measurements of surface forces between bilayers of double-chained quaternary ammonium acetate and bromide surfactants J. Phys. Chem. 90 1637-42... 

Ammonium acetate Ammonium adipate Ammonium benzoate Ammonium bicarbonate Ammonium biflluoride Ammonium binoxalate Ammonium bisulfate Ammonium bitartrate Ammonium tetraborate Ammonium bromide Ammonium carbonate Ammonium chloride Ammonium citrate Ammonium diclnomate Ammonium fluoride Ammonium fluorosilicate Ammonium gluconate Ammonium iodide Ammonium molybdate Ammonium nitrate Ammonium oxalate Ammonium perchlorate Ammonium picrate Ammonium polysulfide Ammonium salicylate Ammonium stearate Ammonium sulfate Ammonium sulfide (hydrosulfide) Ammonium tartrate Ammonium tliiocyanate Ammonium thiosulfate... 

Krohnke observed that phenacylpyridinium betaines could be compared to 3-diketones based on their structure and reactivity, in particular, their ability to undergo Michael additions. Since 3-dicarbonyls are important components in the Hantzsch pyridine synthesis, application of these 3-dicarbonyl surrogates in a synthetic route to pyridine was investigated. Krohnke found that glacial acetic acid and ammonium acetate were the ideal conditions to promote the desired Michael addition. For example, N-phenacylpyridinium bromide 50 cleanly participates in a Michael addition with benzalacetophenone 51 to afford 2,4,6-triphenylpyridine 52 in 90% yield. 

Determination. To an aliquot of the silver(I) solution containing between 10 and 50 pg of silver, add sufficient EDTA to complex all those cations present which form an EDTA complex. If gold is present (>250 xg) it is masked by adding sufficient bromide ion to form the AuBr4 complex. Cyanide, thiocyanate or iodide ions are masked by adding sufficient mercury(II) ions to complex these anions followed by sufficient EDTA to complex any excess mercury(II). Add 1 mL of 20 per cent ammonium acetate solution, etc., and proceed as described under Calibration. 

This transformation can also be carried out under solvent-free conditions in a domestic oven using acidic alumina and ammoniiun acetate, with or without a primary amine, to give 2,4,5-trisubstituted or 1,2,4,5-tetrasubstituted imidazoles, respectively (Scheme 15A) [69]. The automated microwave-assisted synthesis of a library of 2,4,5-triarylimidazoles from the corresponding keto-oxime has been carried out by irradiation at 200 ° C in acetic acid in the presence of ammonium acetate (Scheme 15B) [70]. Under these conditions, thermally induced in situ N - O reduction occurs upon microwave irradiation, to give a diverse set of trisubstituted imidazoles in moderate yield. Parallel synthesis of a 24-membered library of substituted 4(5)-sulfanyl-lff-imidazoles 40 has been achieved by adding an alkyl bromide and base to the reaction of a 2-oxo-thioacetamide, aldehyde and ammonium acetate (Scheme 15C) [71]. Under microwave-assisted conditions, library generation time was dramatically re-... 

A different multicomponent route to imidazoles has been described by the group of O Shea, involving the diversity-tolerant three-component condensation of an aldehyde, a 2-oxo-thioacetamide, and an alkyl bromide (5 equivalents) in the presence of ammonium acetate (Scheme 6.201) [364]. This allowed the preparation of a 24-membered 4(5)-alkylthio-lH-imidazole demonstration library from 21 different aldehydes, 12 alkyl bromides, and two 2-oxo-thioacetamides. The library was synthesized in a parallel format using a custom-built reaction vessel. Alkylthioimidazoles... 

Ammonium acetates, 2 711-712 Ammonium alum calcination, 2 395 neutralization, 2 430 Ammonium benzoate, 3 634 Ammonium bicarbonate, 2 712-713 Ammonium bifluoride, 2 717-718 Ammonium bisulfate formation, 10 98 Ammonium bromide, 2 714... 

RP-HPLC was also employed for the investigation of the hydrolysis behaviour of two fluorotriazine reactive dyes Cibacron blue F-R and Cibacron yellow F-4G. Chromatographic measurements were performed in an ODS column (50 X 4.6 mm i.d. particle size 5 /jm) at room temperature. The mobile phase was ACN-0.05 M ammonium acetate buffer containing 1 mM acetyhrimethylammonium bromide (47 53, v/v). Flow rates were 0.8 and 0.6 ml/min depending on the dyes to be separated. Dyes were detected at 275 nm. The hydrolysis of dyes was investigated both in the absence and presence of... 

To complete the section on the synthesis of 4,4 -bipyridines, we summarize the methods reported for the preparation of some substituted 4,4 -bi-pyridines and 4,4 -bipyridinones. These methods are closely analogous to syntheses already discussed for some of the isomeric bipyridines. Thus the Hantzsch reaction using pyridine-4-aldehyde, ethyl acetoacetate, and ammonia gives 3,5-di(ethoxycarbonyl)-1,4-dihydro-2,6-dimethyl-4,4 -bipyridine, which after oxidation, followed by hydrolysis and decarboxylation, afforded 2,6-dimethyl-4,4 -bipyridine. Several related condensations have been reported. Similarly, pyridine-4-aldehyde and excess acetophenone gave l,5-diphenyl-3-(4-pyridyl)pentane-l,5-dione, which with ammonium acetate afforded 2,6-diphenyl-4,4 -bipyridine. Alternatively, 1-phenyl-3-(4-pyridyl)prop-2-enone, A-phenacylpyridinium bromide, and ammonium acetate gave the same diphenyl-4,4 -bipyridine, and extensions of this synthesis have been discribed. Condensation of pyridine-4-aldehyde with malononitrile in the presence of an alcohol and alkaline catalyst produced compounds such as whereas condensations of... 

The first fully aromatic 2-azaquinolizinium salts were prepared by Krohnke et al. (64CB3566), who examined three approaches to the l-hydroxy-3-phenyI-2-azaquinoIizinium ion (262 Scheme 130). The first involved the reaction of picolinamide (261) with phenacyl bromide which produced (262) in unspecified yield. Most effective was refluxing 2-cyanopyridine (263) in moist acetonitrile with phenacyl bromide. Finally, it was shown that 2-ethoxycarbonyl-l-phenacylpyridinium ion (265) could serve as a starting material if ammonium acetate were present in the solvent. 

A novel approach to the synthesis of a 1,5-naphthyridine starts from quinuclidin-3-one (143), which is first converted to the 2-arylidene derivative and then reacted with phenacyl-pyridinium bromides and ammonium acetate to give l,4-ethano-3,4-dihydro-2//-l,5-naph-thyridines (144) (82S27). 

Ammonium, (methoxycarbonylsulfamoyl)-tnethyl-,hydroxide, 56, 41 Ammonium acetate, (2-phenyl-l-azin-dinyl)-, 55, 114 Amyl bromide,56,82 Aniline, 56, 122, 57, 112 Aniline, 2-bromo-, p-bromination of, 55, 23 Aniline, 3-bromo-,p-bromination of, 55, 23 ANILINE, 4-bromo-Ar,jV-dimethyl-3-(ttl-fluoromethyl)-, 55, 20... 

Volatile buffers were reconsidered for the modified method. Triethylamine was ruled out primarily because it could not be obtained in high purity and because the secondary and primary amines contaminating it could potentially react with solutes present in the water sample. Preliminary evidence of reaction between ethidium bromide and triethylammonium bicarbonate was obtained, but the reaction product was not characterized. The components of volatile buffers that appeared acceptable on the basis of chemical purity were ammonia, acetic acid, and formic acid. A few exploratory experiments were conducted involving the elution by ammonium formate and ammonium acetate of EB or quinaldic acid exchanged onto AG MP-50 or IRA 900. These experiments showed that 1 M ammonium formate in water was a very poor eluent, but that EB could be eluted from AG MP-50 with 1 M ammonium formate in methanol. Elution was essentially complete with 6 bed volumes of the methanolic eluent, whereas neither methanol alone nor aqueous 1 M ammonium formate was able to elute this solute. This situation pointed out the necessity for a counterion to displace exchanged solutes and, additionally, indicated that the displaced solute be highly soluble in the eluting solvent. 

From this ranking, quaternary ammonium acetates, chlorides, nitrates, and bromides are apparently more soluble in organic solvents such as aqueous /-butyl alcohol than are the corresponding quaternary ammonium hydroxides. Thus these quaternary ammonium salts would be readily extracted into the organic phase. In addition, a high concentration of... 

The structures of these bisindole maleimides were confirmed by synthesis. The reaction of indolyl magnesium bromide (10) with 2,3-dibromo-A -methylmaleimide (11) in toluene led to bisindolylmaleimide (12), which was converted into arcyriarubin A (6) through alkaline hydrolysis followed by heating with ammonium acetate (Scheme 1). The reaction of 10 and 11 in THF yielded monosubstitution product (13) which after protection of the indole NH group with the Boc residue was used to prepare unsymmetrically substituted bisindolylmaleimide, arcyriarubin B (1) [8]. 

Mercury diphenyl has been prepared in a number of ways. The most important methods are by the action of sodium on a mixture of bromobcnzene and mercuric chloride 1 from sodium amalgam and phenyl mercuric iodide 2 by the interaction of phenyl mercuric bromide and potassium sulfide2 or phenyl mercuric acetate and sodium stannite 3 from phenyl magnesium bromide and mercuric chloride 4 by the action of phenyl hydrazine on mercury compounds 5 from mercuric chloride and phenyl arsenious oxide 6 and from diphenyl mercuric ammonium acetate and sulfur compounds.7... 

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