Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Ammonium salts reduction

Ethylamine, monoethylamine, CH3CH2NH2-B.p. 19 C. Prepared by reduction of acetonitrile or by heating ethyl chloride with alcoholic ammonia under pressure. It is a strong base and will displace ammonia from ammonium salts. Forms a crystalline hydrochloride and also crystalline compounds with various metallic chlorides. [Pg.166]

If the acid of the ammonium salt is an oxidising agent, then on heating the salt, mutual oxidation and reduction occurs. The oxidation products can be nitrogen or one of its oxides and the reactions can be explosive, for example ... [Pg.221]

Both in situ cross-linking of partially hydroly2ed polyacrylamides (69) and injection of quaternary ammonium salt polymers having long hydrophilic side chains (70) have been used to reduce the permeabiUty of water-producing 2ones adjacent to production wells. This permeabiUty reduction decreases the produced water oil ratio as does injection of polyacrylamide in high hardness brine to reduce permeabiUty (71). [Pg.191]

The Leuckart reaction uses formic acid as reducing agent. Reductive alkylation using formaldehyde, hydrogen, and catalyst, usually nickel, is used commercially to prepare methylated amines. These tertiary amines are used to prepare quaternary ammonium salts. [Pg.219]

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). [Pg.314]

Benzofurazan, 7-chloro-4-nitro-, 6, 394 as fluorigenic agents, 6, 410, 426 Benzofurazan, 4-chloro-7-sulfo-ammonium salt properties, 6, 426 Benzofurazan, 4-nitro-synthesis, 6, 408 Benzofurazans, 6, 393-426 Beckmann fragmentation, 6, 412 biological activity, 6, 425 bond angles, 6, 396 bond lengths, 6, 396 diazo coupling, 6, 409 dipole moments, 6, 400 electrochemical reduction, 5, 73 electrophilic reactions, 6, 409-410 ESR spectroscopy, 6, 400... [Pg.549]

Unloaded silica does not recover HPA from aqueous solution. The surface of silica gel modified with quarternary ammonium salts (QAS) gets anion-exchange properties. The aim of the work is the elaboration of solid-phase reagents on the base of ion associate of HPA with QAS immobilized onto silica surface for the determination of phosphoms and organic reductants. Heterocyclic (safranine and lucigenine) and aliphatic (trinonyloctadecyl ammonium iodide and tetradecyl ammonium nitrate) compounds have been examined as QAS. [Pg.60]

It is shown that both Sb(III) and Bi(III) can speed reduction of 12-molybdophosphate (12-MPC) to the corresponding heteropoly blue (12-MPB) by ascorbic acid (AA). It is found that mixed polyoxometalates can be formed in solution which reduce considerably more rapidly than 12-MPC. Complete formation of mixed POM is observed only if significant excess of Me(III) ions is used in the reaction. POM responsible for blue color was synthesized by selective extraction. Chemical analysis of tetrabutyl-ammonium salt is in accordance with formula of (TBAl PMeflllfMo O j (Me = Sb, Bi). IR spectmm of mixed POM is identical to 12-MPC. [Pg.156]

It is known that Selenium catalyzes reaction of some dye reduction by Sulphide. On this basis spectrophotometric and test-techniques for Selenium determination are developed. Inefficient reproducibility and low sensitivity are their deficiencies. In the present work, solid-phase reagent on silica gel modified first with quaternary ammonium salt and then by Indigocarmine was proposed for Selenium(IV) test-determination. Optimal conditions for the Selenium determination by method of fixed concentration were found. The detection limit of Se(IV) is 10 ftg/L = 2 ng/sample). Calibration curve is linear in the range 50-400 ftg/L of Se(IV). The proposed method is successfully applied to the Selenium determination in multivitamins and bioadditions. [Pg.397]

Methylsuccinic acid has been prepared by the pyrolysis of tartaric acid from 1,2-dibromopropane or allyl halides by the action of potassium cyanide followed by hydrolysis by reduction of itaconic, citraconic, and mesaconic acids by hydrolysis of ketovalerolactonecarboxylic acid by decarboxylation of 1,1,2-propane tricarboxylic acid by oxidation of /3-methylcyclo-hexanone by fusion of gamboge with alkali by hydrog. nation and condensation of sodium lactate over nickel oxide from acetoacetic ester by successive alkylation with a methyl halide and a monohaloacetic ester by hydrolysis of oi-methyl-o -oxalosuccinic ester or a-methyl-a -acetosuccinic ester by action of hot, concentrated potassium hydroxide upon methyl-succinaldehyde dioxime from the ammonium salt of a-methyl-butyric acid by oxidation with. hydrogen peroxide from /9-methyllevulinic acid by oxidation with dilute nitric acid or hypobromite from /J-methyladipic acid and from the decomposition products of glyceric acid and pyruvic acid. The method described above is a modification of that of Higginbotham and Lapworth. ... [Pg.56]

Diphenylisoinclole (29) can be prepared by a modified Leuckart reaction of o-dibenzoylbenzene (46), using an ammonium salt of formic acid the process is essentially a reductive alkylation of ammonia, accompanied by cyclization, and leads to 29 in 44% yield with ammonium formate, and 47 in 28% yield with methylammonium formate. 1,3-Diphenylisoindole. (29) can also be obtained in good yield by the reaction of 46 with 1,1-dimethylhydrazine. ... [Pg.125]

Hofmann rearrangement, 933 imide (-CONHCO—), 929 primary amine (RNH2), 916 quaternary ammonium salt, 917 reductive amination, 930 Sandmeyer reaction, 942 secondary amine (R2NH), 917 tertiary amine (R3N), 917... [Pg.958]

To reduce fluorine content in (NFL MOg, the precipitate is washed. Use of water as a washing solution ensures a significant reduction of the fluorine content however, the process seems to be of low efficiency due to the relatively high solubility of ammonium peroxometalates. According to Belov et al. [512], solubility of the ammonium peroxometalates depends on the concentration of the ammonium salts. The solubility of ammonium peroxometalates (CM () ) in solutions of various ammonium salts can be... [Pg.307]

As the acetonitrile concentration increased, however, the concentration of adsorbed tetrabutyl ammonium salt would also be reduced and it would be desorbed from the reverse phase with a resulting reduction in the ionic interactions of the solutes with the stationary phase. At higher concentrations of acetonitrile, the tetrabutyl ammonium salt would be completely desorbed from the stationary phase and the interactions of the solutes with the stationary phase would become almost exclusively dispersive. This is an example... [Pg.303]

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... [Pg.38]


See other pages where Ammonium salts reduction is mentioned: [Pg.243]    [Pg.191]    [Pg.112]    [Pg.294]    [Pg.228]    [Pg.57]    [Pg.757]    [Pg.255]    [Pg.243]    [Pg.191]    [Pg.112]    [Pg.294]    [Pg.228]    [Pg.57]    [Pg.757]    [Pg.255]    [Pg.452]    [Pg.326]    [Pg.379]    [Pg.275]    [Pg.383]    [Pg.480]    [Pg.63]    [Pg.15]    [Pg.258]    [Pg.109]    [Pg.1014]    [Pg.187]    [Pg.530]    [Pg.1654]    [Pg.6]    [Pg.193]    [Pg.269]    [Pg.109]   


SEARCH



Ammonium reduction

Reduction salts

© 2024 chempedia.info