Nitric acid halides

Principle. A known weight of the substance is heated with fuming nitric acid and silver nitrate in a sealed tube. The organic material is thus oxidised to carbon dioxide and water, whilst the halogen is converted quantitatively into the corresponding silver halide. The latter js subsequently washed out of the tube, filtered and weighed. 

Principle. This is essentially a small-scale modification of the macro piethod described on p. 416, the substance being completely oxidised in a sealed tube with fuming nitric acid in the presence of silver nitrate, the halogen being thus converted into silver halide. The collection and weighing of the silver halide require special techniques on the semi-micro scale. 

Sulphur, as sulphide ion, is detected by precipitation as black lead sulphide with lead acetate solution and acetic acid or with sodium plumbite solution (an alkaLine solution of lead acetate). Halogens are detected as the characteristic silver halides by the addition of silver nitrate solution and dilute nitric acid the interfering influence of sulphide and cyanide ions in the latter tests are discussed under the individual elements. 

Nitric acid, fuming Organic matter, nonmetals, most metals, ammonia, chlorosulfonic acid, chromium trioxide, cyanides, dichromates, hydrazines, hydrides, HCN, HI, hydrogen sulflde, sulfur dioxide, sulfur halides, sulfuric acid, flammable liquids and gases... 

Nitromethane Acids, alkylmetal halides, hydroxides, hydrocarbons, organic amines, formaldehyde, nitric acid, perchlorates... 

Esterification. Esters are formed by the reaction of ethanol with inorganic and organic acids, acid anhydrides, and acid halides. If the inorganic acid is oxygenated, eg, sulfuric acid, nitric acid, the ester has a carbon—oxygen linkage that is easily hydrolyzed (24—26). 

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. ... 

The Halogens Carh/s).—The method of Carius, which is usually emplo ed, consists in oxidising the substance with fuming nitric acid under piessure in presence of silver nitrate. The silver halide which is formed is then separated by filtration and w eighed. 

Nitrogen forms two series of oxohalides — the nitrosyl halides XNO and the nitryl halides XNO2. There are also two halogen nitrates FONO2 (bp -46°) and CIONO2 (bp 22.3°), but these do not contain N-X bonds and can be considered as highly reactive derivatives of nitric acid, from which they can be prepared by direct halogen ation ... 

Iodides can also be determined by this method, and in this case too there is no need to filter off the silver halide, since silver iodide is very much less soluble than silver thiocyanate. In this determination the iodide solution must be very dilute in order to reduce adsorption effects. The dilute iodide solution (ca 300 mL), acidified with dilute nitric acid, is treated very slowly and with vigorous stirring or shaking with standard 0.1 M silver nitrate until the yellow precipitate coagulates and the supernatant liquid appears colourless. Silver nitrate is then present in excess. One millilitre of iron(III) indicator solution is added, and the residual silver nitrate is titrated with standard 0.1M ammonium or potassium thiocyanate. 

The recovered resin can be reconverted to the hydroxide form by eluting a column of the material with aqueous 10% sodium hydroxide until it is free of halide ion (silver nitrate-nitric acid test) and then with water until the eluent is no longer alkaline to pH paper. 

When nitronium salts are used, NOj is of course present to begin with. Esters and acyl halides of nitric acid ionize to form NOj. Nitrocyclohexadienones are converted to NO2 and the corresponding phenol." ... 

Such reactions can be promoted by exposing the chromatogram to the vapors of hydrogen halides, to nitric acid fumes [4], to ammonia or oxides of nitrogen [2] in suitable reaction chambers [10]. Ammonium hydrogen carbonate, first proposed by SEGxmA and Gono is also suitable [11]. 

See Silver bromate Sulfur compounds Nitric acid Sulfur halides... 

See Dinitrogen pentaoxide Sulfur dichloride Nitric acid Sulfur halides Perchloryl fluoride Hydrocarbons, etc. 

Nitrogen triiodide a-Nitroguanidine Nitromethane Acids, bromine, chlorine, hydrogen sulfide, ozone Complex salts of mercury and silver Acids, alkylmetal halides, hydroxides, hydrocarbons, organic amines, formaldehyde, nitric acid, perchlorates... 

Palladium Paraformaldehyde Paraldehyde Pentaborane-9 Pentacarbonyliron Arsenic, carbon, ozonides, sulfur, sodium tetrahydridoborate Liquid oxygen Alkalies, HCN, iodides, nitric acid, oxidizers Dimethylsulfoxide Acetic acid, nitric oxide, transition metal halides, water, zinc... 

Reaction of hydrazinoazines with nitric acid has also proved to be suitable route to form azido moieties to complement the nucleophilic exchange reaction of a halide for an azide. This approach has also been applied recently for the synthesis of fused tetrazoles, and these transformations are shown in Scheme 24. 

Clean the outside of the tube and cautiously dilute the contents with 10 c.c. of water. The small tube which contained the nitric acid rises to the surface. Grasp this tube with a pair of bone-tipped forceps, empty its contents into a beaker having a rounded bottom (depth 15 cm., width 3-3-5 cm.), and wash with distilled water. Break up the silver halide as much as possible with a glass rod and transfer the contents of the Carius tube quantitatively to the beaker, washing out repeatedly. With a glass rod remove any silver halide... 

Transfer the silver halide precipitate to the filter by means of a delivery tube (Fig. 41), previously carefully cleaned. Attach the delivery tube to the filter tube by means of a small rubber stopper. Lower the delivery tube to the bottom of the beaker and draw over the precipitate at a moderate speed (about two drops per second). Then wash with a little alcohol and, when the alcohol has been drawn through, with a little dilute nitric acid (1 100). If necessary repeat the successive washing with a little alcohol and a little water. Finally wash with alcohol the end of the delivery tube which is in the filter tube, fill the cup of the filter... 

Figure 5.8 The reactions between toluene and nitric acid in (a) a halide-based ionic liquid, (b) a triflate-based ionic liquid, and (c) a mesylate-based ionic liquid.

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