Ammonium cyanide

Heating with zirconium chloride gives a tetraamine adduct  

Ammonium chloride is analyzed by treatment with formaldehyde (neutralized with NaOH) and the product HCl formed is analyzed by titration using an acid-base color indicator such as phenolphthalein. Alternatively, it may be mixed with caustic soda solution and distdled. The distillate may be analyzed for NH3 by titration with H2SO4 or by colorimetric Nesslerization or with an ammonia-selective electrode (APHA, AWWA, WEF. 1995. Standard Methods for the Examination of Water and Wastewater. 19th ed. Washington, DC, American Pubhc Health Association). The presence of ammonia or any other ammonium compound would interfere in the test. The moisture content in NH4CI may be determined by Karl—Fischer method. 

NH4CN is used in organic synthesis. Unstable, it is not shipped or sold commercially. 

Colorless crystalline solid cubic crystal unstable density 1.02 g/cm decomposes at 36°C sublimes at 40°C very soluble in cold water and alcohol decomposes in hot water. 

Ammonium cyanide is prepared in solution by bubbling hydrogen cyanide into aqueous ammonia at low temperature  

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Ammonia and carbon at red heat give ammonium cyanide [12211 -52-8], NH CN. 

Dehalogenation of monochlorotoluenes can be readily effected with hydrogen and noble metal catalysts (34). Conversion of -chlorotoluene to Ncyanotoluene is accompHshed by reaction with tetraethyl ammonium cyanide and zero-valent Group (VIII) metal complexes, such as those of nickel or palladium (35). The reaction proceeds by initial oxidative addition of the aryl haHde to the zerovalent metal complex, followed by attack of cyanide ion on the metal and reductive elimination of the aryl cyanide. Methylstyrene is prepared from -chlorotoluene by a vinylation reaction using ethylene as the reagent and a catalyst derived from zinc, a triarylphosphine, and a nickel salt (36). 

Ammonium cyanide [12211-52-8] NH CN, a colorless crystalline soHd, is relatively unstable, and decomposes into ammonia and hydrogen cyanide at 36°C. Ammonium cyanide reacts with ketones (qv) to yield aminonitriles. Reaction of ammonium cyanide with glyoxal produces glycine. Because of its unstable nature, ammonium cyanide is not shipped or sold commercially. Unless it is kept cool and dry, decomposition releases vapors and forms black hydrogen cyanide polymer. 

Ammonium cyanide may be prepared in solution by passing hydrogen cyanide into aqueous ammonia at low temperatures. It may also be prepared from barium cyanide and ammonium sulfate, or calcium cyanide with ammonium carbonate. It may be prepared in the dry state by gentiy heating a mixture of potassium cyanide or ferrocyanide and ammonium chloride, and condensing the vapor in a cooled receiver. Ammonium cyanide is soluble in water or alcohol. The vapor above soHd NH CN contains free NH and HCN, a very toxic mixture. 

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. ... 

Cyan-, of or combined with cyanogen, cyano-(as Cyanpropionadure, cyanopropionic acid), cyanide of (as Cyanammonium, ammonium cyanide), -alkali, n. alkali cyanide, -alkyl, n. alkyl cyanide. 

Oro j. Synthesis of adenine from ammonium cyanide. Biochem. Biophys. Res. Commun. 1960 2 407-412. 

Write the formula for each of the following compounds (a) hydrogen iodide, (b) calcium chloride, (c) lithium oxide, (d) silver nitrate, (e) iron(II) sulfide, (/) aluminum chloride, (g) ammonium sulfate, (h) zinc carbonate, (/) iron(lll) oxide, ( ) sodium phosphate, (k) iron(H) acetate, (/) ammonium cyanide, and (m) copper(II) chloride. 

Write formulas for each of the following compounds (a) ammonium cyanide, (ft) mercury I) nitrate, and (< ) uranyl sulfate. 

Oro s experiment (Oro, 1960) was very simple he heated ammonium cyanide to 343 K and was able to detect adenine after a few days. Shortly afterwards, he showed that five molecules of HCN combined to give one of adenine (Oro, 1961). An intermediate, aminomalonitrile, can be converted to 4-aminoimidazole-5-carboxamide in two different ways (Sanchez et al., 1966a, b) (Fig. 4.4) ... 

The purine base guanine is also formed in concentrated solutions of ammonium cyanide, i.e., the same substance which became known from Or6 s adenine synthesis. Or6, as well as Stanley Miller, was involved in a new series of experiments (Levi et al., 1999). The yield of guanine is, however, 10 10 times lower than that of adenine surprisingly, the synthesis is just as effective at 253 K as at 353 K. Low temperatures seem conceivable in certain parts of Earth as well as on the Jovian moon Europa (see Sect. 3.1.5) or in the Murchison meteorite. 

A more recent, extended study of purine synthesis via polymerisation of ammonium cyanide, described at the beginning of this section, showed that the yield of adenine from the non-hydrolyzed solution was only slightly temperature dependent. Shorter hydrolysis times for the insoluble polymerisation products led to higher adenine yields. When the solution is hydrolyzed at pH 8, the adenine yield is comparable to the value of 0.1% found for acidic hydrolysis (a model for the primeval ocean ). Increasing the hydrolysis time has no effect on the adenine yield because of its greater stability at pH 8. Hydrolysis of the black NH4CN polymer under acidic or neutral conditions results in an adenine yield of about 0.05% (Borquez et al., 2005). 

Ammonium cyanide, 8 194 Ammonium derivatives, quaternary, 24 45 Ammonium dichromate, 6 538 manufacture, 6 541 Ammonium dichromate(VI), physical properties, 6 528t... 

Remarks on Sections 6 and 7.-—The method here described for the synthesis of cyanohydrins—treatment of the bisulphite compound of the aldehyde with potassium cyanide—cannot be used in all cases. Concentrated solutions of hydrocyanic acid or anhydrous hydrogen cyanide are often used. The general method for the synthesis of a-amino-acids, the nitriles of which are formed by the union of ammonium cyanide with aldehydes or ketones (Strecker), is to be contrasted with that for the synthesis of a-hydroxy acids. For additional amino-acid syntheses see Chap. VII. 2, p. 276. 

In addition to this, the simplest method of synthesising a-amino-acids (a method which is less satisfactory for the preparation of higher members of the series), there are two other processes, both starting from aldehydes. Strecker obtained the nitrile of the amino-acid, Chap. V. 7, p. 229, by addition of ammonium cyanide to the next lower aldehyde, and Erlenmeyer jun. condensed hippuric acid with the aldehyde containing two carbon atoms less than the required amino-acid. 

The simplest C-C bond formation reaction is the nucleophilic displacement of a halide ion from a haloalkane by the cyanide ion. This was one of the first reactions for which the kinetics under phase-transfer catalysed conditions was investigated and patented [l-3] and is widely used [e.g. 4-12], The reaction has been the subject of a large number of patents and it is frequently used as a standard reaction for the assessment of the effectiveness of the catalyst. Although the majority of reactions are conducted under liquiddiquid two-phase conditions, it has also been conducted under solidrliquid two-phase conditions [13] but, as with many other reactions carried out under such conditions, a trace of water is necessary for optimum success. Triphase catalysis [14] and use of the preformed quaternary ammonium cyanide [e.g. 15] have also been applied to the conversion of haloalkanes into the corresponding nitriles. Polymer-bound chloroalkanes react with sodium cyanide and cyanoalkanes under phase-transfer catalytic conditions [16],... 

Lubavin, in 1882, stated that glycine was formed by the action of ammonium cyanide upon glyoxal, which probably first breaks down into formaldehyde and then by the cyanhydrin reaction yields glycine —... 

Reacts with carbon at red heat to give ammonium cyanide, NH4CN forms phosphine and nitrogen upon reaction with phosphorus vapor at red heat ... 

In dry state, NH4CN is made by heating a mixture of potassium cyanide or potassium ferrocyanide with ammonium chloride and condensing the vapors into ammonium cyanide crystals ... 

Ammonium cyanide decomposes to ammonia and hydrogen cyanide often forming black polymer of HCN ... 

Ammonium cyanate also may be prepared by direct sulfurization of ammonium cyanide. 

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