Cyanide radical

The dissociation of the CN radical has been investigated by shocking mixtures of BrCN [130] or CiNj diluted by inert gas at high temperatures. In the temperature range 3400—7000°K, it has been proposed that the disappearance of CN occurs via the metathetical reaction [131,132] 

A computer analysis has shown that the following scheme is general and accounts for the results over wide density and temperature ranges [20]. 

The value of used to fit the concentration profiles was 1.2 x 10 exp (—142,000/i T). The activation energy was 38 kcal mole less than the recommended value of 180 kcal mole . The above steps have also been incorporated into the computer fitting of the cyanogen dissociation [21]. 

The preceding discussion of diatomic dissociations and recombinations may be highlighted by the following points. 

The picture that emerges is that there is a considerable amount of atom switching events occurring before the onset of dissociation. It has been proposed that the reactive channels for exchange are vibrational states far below the bound limit e.g., i = 4 for deuterium [51]. The non-linear production of exchange products and the inert gas order dependence in the rate law identifies the exchange mechanism as a sequence of steps rather than one four-centre encounter. Whether or not atom switching is an important precursor to dissociation remains to be demonstrated. 

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In addition to the irritant effects, cyanogen chloride may also cause interference with cellular metabolism via the cyanide radical. Cyanide ion exerts an inhibitory action on certain metabolic enzyme systems, most notably cytochrome oxidase, the enzyme involved in the ultimate transfer of electrons to molecular oxygen. Because cytochrome oxidase is present in practically all cells that function under aerobic conditions, and because the cyanide ion diffuses easily to all parts of the body, cyanide quickly halts practically all cellular respiration. The venous blood of a patient dying of cyanide is bright red and resembles arterial blood because the tissues have not been able to utilize the oxygen brought to them. Cyanide intoxication produces lactic acidosis, probably the result of increased rate of glycolysis and production of lactic acid. ... 

For the case of acrylonitrile, there was an induction time of 24 h. This was attributed to the formation of cyanide radicals which are able to react with polyamidic macroradicals. The interpolymer is composed of two fractions one soluble in dimethyl formamide, whose properties are similar to polyacrylonitrile the other, insoluble in this solvent, whose properties are similar to those of the polyamide. No homopolymer was observed. The presence of acrylonitrile on the graft polymer was demonstrated by IR. 

Interestingly, sodium salts, usable as the needed soda additive in the Rostoker process, is a by-product from another system (patent issued) which destroys the cyanide radical in concentrated aqueous wastes. This was developed by Rostoker, Inc. This system will accept wastes with up to 250,000 ppm CN, including complexed ferrocyanides. Water of acceptable discharge quality is produced. Solid salts, which are largely sodium hydroxide and carbonate, are fed to a furnace in combination with F006 sludges. 

An exception is the reaction of "OH with the cyanide ion. Its OH adduct rapidly protonates even at high pH, but in this reaction the cyanide radical is not formed because of its very high reduction potential (Wardman 1989). It rather undergoes an enol— keto tautomerization [overall reaction (7) Behar and Fessenden 1972 Behar 1974 Biichler et al. 1976 Bielski and Allen 1977 Munoz et al. 2000]. 

When another equivalent of sodium cyanide is added the precipitate entirely redissolves. In this solution the silver is found to be in the negative ion, and to be associated with 2 cyanide radicals. 

Nitriles are directly converted to esters by heating with an alcohol and sulfuric or hydrochloric acid. When water is absent, the imino ester salt is readily isolated (method 402). Aliphatic,aromatic, and heterocycliccyano compounds react in this manner. Most of the aromatic compounds contain a cyanomethyl group although the cyanide radical may be attached directly to the aromatic nucleus. Monosub-stituted malonic esters free from unsubstituted and disubstituted malonic esters are made from the corresponding a-cyano esters by this method. Malonic ester and disubstituted malonic esters have been similarly prepared. ... 

By this synthesis, it will be noticed that the alpha- immo acids result as the amino group is always linked to the carbon to which the carboxyl is also linked. The amino acid will also contain one more carbon than the aldehyde or ketone due to the addition of the cyanide radical, i.e.y acetic aldehyde yields amino propionic acid and propanone (acetone) yields amino iso-butyric acid. 

The cyanide radical is one of the examples of a radical existing as such. It is known as cyanogen and is made by heating mercuric cyanide just as oxygen is made by heating mercuric oxide. 

Numerous plating and metal finishing plants use chemical oxidation methods to treat their cyanide wastes cyanides and heavy metals are often present together in plating industry waste. Their concentration and their value influence the selection of the treatment process. If the cyanide and heavy metals are not economically recoverable by a method such as ion exchange, the cyanide radical is converted either to the less toxic cyanate or to carbon dioxide and nitrogen by oxidation, while the heavy metals are precipitated and removed as sludge. 

The Mo(V) complex [Mo(CN)J primarily undergoes photoreduction to Mo(IV) derivatives simultaneously with substitution. This photoredox proceeds by the intermediate production of cyanide radicals, [CN]. ... 

Cyanamide, calcium salt Cyanamide, dimethyl-Cyanic acid, potassium salt Cyanide ion Cyanide radical... 

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