Sodium cyanide, also

The sulfonate salts of the --deficient heterocycles will undergo many reactions typical of arenesulfonates, such as displacement by hydroxide, on fusion with alkali (e.g. Scheme 129), or by cyanide on fusion with potassium or sodium cyanide. Also, the sulfonation of pyridine is reversible when pyridine-3-sulfonic acid is heated with 100% sulfuric acid and mercury(II) sulfate at approximately 330 °C a mixture is obtained containing mainly pyridine (58RTC963). 

Cyanide. Potassium cyanide, [CAS 151-50-8], cyanide of potash, KCN, white solid, soluble, very poisonous, formed by reaction of calcium cyanamide and potassium chloride at high temperature. Used as a source of cyanide and for hydrocyanic acid, but usually replaced by the cheaper sodium cyanide. Also used in metallurgy, electroplating,... 

Sodium cyanide also is used in chemical synthesis. As previously mentioned, sodium cyanide is used to produce the sequestrant EDTA [82]. Chloroacetic acid reacts with sodium cyanide in the presence of soda ash to yield cyano-acetic acid. Sodium cyanide reacting with a-chloromethylnaphthalene followed by hydrolysis yields a-naphthaleneacetamide and the corresponding carboxylic acid these are two of several common plant hormones, growth acceler-... 

Some basic physical properties of sodium cyanide are shown in Table 39.1. It should be noted that sodium cyanide has only a faint odor and is not detectable at concentrations that would provide a margin of safety. Sodium cyanide also sinks and is quite soluble in water— 480,000 ppm at a temperature of 10°C. There are two different hydrates of sodium cynanide the more common NaCN-2H20 (below 35°C) and NaCN-y2 H2O (>35°C) (Environment Canada, 1984 Ullmann s, 1987). 

Direct reaction of the bisulphite adduct, 3-phenoxy-a-hydroxybenzylsulfonate, with sodium cyanide also gives the desired cyanohydrine [632]. 

Zinc cyanide. Solutions of the reactants are prepared by dis solving 100 g. of technical sodium cyanide (97-98 per cent. NaCN) in 125 ml. of water and 150 g. of anhydrous zinc chloride in the minimum volume of 50 per cent, alcohol (1). The sodium cyanide solution is added rapidly, with agitation, to the zinc chloride solution. The precipitated zinc cyanide is filtered off at the pump, drained well, washed with alcohol and then with ether. It is dried in a desiccator or in an air bath at 50°, and preserved in a tightly stoppered bottle. The yield is almost quantitative and the zinc cyanide has a purity of 95-98 per cent. (2). It has been stated that highly purified zinc cyanide does not react in the Adams modification of the Gattermann reaction (compare Section IV,12l). The product, prepared by the above method is, however, highly satisfactory. Commercial zinc cyanide may also be used. 

Chrysean (10), prepared by bubbling hydrogen sulfide through a sodium cyanide solution, was among the first described thiazoles (53-57). Other 5-aminothiazoles are also most easily prepared bv hetero-cyclization (see Chapter 11. Section II.5.A). 

Nitdles may be prepared by several methods (1). The first nitrile to be prepared was propionitdle, which was obtained in 1834 by distilling barium ethyl sulfate with potassium cyanide. This is a general preparation of nitriles from sulfonate salts and is referred to as the Pelou2e reaction (2). Although not commonly practiced today, dehydration of amides has been widely used to produce nitriles and was the first commercial synthesis of a nitrile. The reaction of alkyl hahdes with sodium cyanide to produce nitriles (eq. 1) also is a general reaction with wide appHcabiUty ... 

Miscellaneous Reactions. Sodium bisulfite adds to acetaldehyde to form a white crystalline addition compound, insoluble in ethyl alcohol and ether. This bisulfite addition compound is frequendy used to isolate and purify acetaldehyde, which may be regenerated with dilute acid. Hydrocyanic acid adds to acetaldehyde in the presence of an alkaU catalyst to form cyanohydrin the cyanohydrin may also be prepared from sodium cyanide and the bisulfite addition compound. Acrylonittile [107-13-1] (qv) can be made from acetaldehyde and hydrocyanic acid by heating the cyanohydrin that is formed to 600—700°C (77). Alanine [302-72-7] can be prepared by the reaction of an ammonium salt and an alkaU metal cyanide with acetaldehyde this is a general method for the preparation of a-amino acids called the Strecker amino acids synthesis. Grignard reagents add readily to acetaldehyde, the final product being a secondary alcohol. Thioacetaldehyde [2765-04-0] is formed by reaction of acetaldehyde with hydrogen sulfide thioacetaldehyde polymerizes readily to the trimer. 

Calcium cyanamide can be converted to calcium cyanide [592-01-8], used ia cyanidation of metallic ores and production of sodium cyanide and ferrocyanides (11) (see Cyanides). Calcium cyanamide has also been used to make cyanamide which ia turn is the starting material for important iadustrial organic syntheses. 

Sodium cyanide, when fused with sulfur or a polysulftde, is converted into sodium thiocyanate [574-32-7], this compound is also formed when a solution of sodium cyanide is boiled with sulfur or a polysulftde ... 

Typical analysis for the neutralization wet process product is given in Table 5. Sodium cyanide is packed in mild steel or fiber dmms and in 1.4 t Flo-bins. Dry sodium cyanide is also shipped in wet-flo tank cars and tmcks of up to 32 t net. At destination, water is circulated through the wet-flo car or trailer to dissolve the dry sodium cyanide at deUvery. This type of shipment reduces freight costs and reduces environmental risks compared with 30% aqueous solution shipment. Safety regulations are imposed by the various shipping lines and by the countries in which cyanide is transported. 

Use for heat treating is also small compared to the past. It has been supplanted to a large extent by furnaces using special atmospheric conditions. Heat treatment salts containing sodium cyanide are used for small metal parts when selective case hardening is required. 

Many reactions can be carried out between potassium cyanide and organic compounds with the alkalinity of the KCN acting as a catalyst these reactions are analogous to reactions of sodium cyanide. The reactions of potassium cyanide with sulfur and sulfur compounds are also analogous to those of sodium cyanide. Potassium cyanide is reduced to potassium metal and carbon by heating it out of contact with air in the presence of powdered magnesium. Magnesium is converted to the nitride ... 

Potassium cyanide is primarily used for fine silver plating but is also used for dyes and specialty products (see Electroplating). Electrolytic refining of platinum is carried out in fused potassium cyanide baths, in which a separation from silver is effected. Potassium cyanide is also a component of the electrolyte for the analytical separation of gold, silver, and copper from platinum. It is used with sodium cyanide for nitriding steel and also in mixtures for metal coloring by chemical or electrolytic processes. 

Black cyanide is also used ia the processes ia which the gold complexes are adsorbed on carbon. To recover the gold from the carbon a more concentrated solution of sodium cyanide is used. 

Amino-5-nitrosopyrimidines also condense with benzoylacetonitrile, phenacyl-pyridinium bromide and acetonylpyridinium chloride in the presence of sodium cyanide to produce. 7-amino-6-pteridinyl ketones (63JOC1197). Pteridine syntheses from pyridinium salts are not limited to the preparation of pteridyl ketones since pyridinium acetamide... 

This method is particularly applicable to the more reactive benzyl halides which are easily hydrolyzed in the aqueous media usually employed for the metathetical reaction with alkali cyanides. For example, anisyl chloride treated with sodium cyanide in aqueous dioxane gives, as a by-product, 5-10% of anisyl alcohol as determined by infrared analysis. The use of anhydrous acetone not only prevents hydrolysis to the alcohol but also decreases the formation of isonitriles. This method was also applied successfully by the submitters to the preparation of -chlo-rophenylacetonitrile in 74% yield. 

This method is an adaptation of that of Dengel. -Methoxy-phenylacetonitrile can also be prepared by the metathetical reaction of anisyl chloride with alkali cyanides in a variety of aqueous solvent mixtures by the nitration of phenylaceto-nitrile, followed by reduction, diazotization, hydrolysis, and methylation 1 by the reduction of ct-benzoxy- -methoxy-phenylacetonitrile (prepared from anisaldehyde, sodium cyanide, and benzoyl chloride) and by the reaction of acetic anhydride with the oxime of -methoxyphenylpyruvic acid. ... 

The enhanced reactivity of fluoroalkyl ketones is also manifested in the failure to stop the reaction with hydrogen cyanide at the stage of cyanohydrins Instead, oxazohdinones or dioxolanones are formed (equation 11) If, however, the reaction IS conducted under basic conditions with sodium bisulfite and sodium cyanide, the desired cyanohydrin can be prepared [ll ... 

Thiohydantoin 9 was obtained from the treatment of carbonyl 1 with carbon disulfide and ammonium cyanide in aqueous methanol. The transformation could also be carried out step-wise, that is, treatment of 1 with ammonium cyanide to form aminonitrile 10 followed by reaction with carbon disulfide to produce thiohydantoin 9. Alternatively, 5,5-disubstituted 4-thiohydantoins could be prepared by the reaction of ketones with ammonium monothiocarbamate and sodium cyanide. ... 

The utility of 2,2 -biindolyl derivatives as indolocarbazole precursors has also been exploited extensively by Somei and co-workers, who reported the first syntheses of the naturally occurring indolo[2,3-a]carbazoles 16 and 17 (Scheme 9). A chloroacetylation of 2,2 -biindolyl (46) followed by treatment of the resulting product 58 with sodium cyanide in formamide-methanol provided 59. Transformation of 59 into the acetoxy derivative 60, followed by hydrolysis to 61, finally led to the target compounds after subsequent sequential melhylations [97H(45)1647]. 

The 5-methyl-5-ethyloxazolidine-2,4-dione may be prepared by reacting methyl ethyl ketone with sodium cyanide and with ammonium thiocyanate followed by desulfurization. This intermediate may also be prepared by condensing a-hydroxy-a-methylbutyramide with ethyl chlorocarbonate or by condensing ethyl a-hydroxy-a-methylbutyrate with urea. Another method described (Traube and Aschar, Ber., 46, 2077-1913) consists in the condensation of ethyl a-hydroxy-a-methylbutyrate with guanidine followed by hydrolysis. 

Hydrogen cyanide is a reactant in the production of acrylonitrile, methyl methacrylates (from acetone), adiponitrile, and sodium cyanide. It is also used to make oxamide, a long-lived fertilizer that releases nitrogen steadily over the vegetation period. Oxamide is produced by the reaction of hydrogen cyanide with water and oxygen using a copper nitrate catalyst at about 70°C and atmospheric pressure ... 

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