592-04-1 mercuric cyanide

Strnctnre tetragonal crystals Synonym mercnry(ll) cyanide 

TABLE 14.2 Toxicity and Hazardous Reactions of Misceiianeous inorganic Cyanides 

Compound/Synonyms/ CAS No. FormuWMW Toxicity Hazardous Reactions 

Ammonium cyanide NH4CN Highly toxic toxic effects Readily decomposes to 

Lithium cyanide LiCN Highly toxic toxic Produces toxic HCN 

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Mercuric Cyanides. Mercuric cyanide7, Hg(CN)2, is a white tetragonal crystalline compound, Httle used except to a small degree as an antiseptic. It is prepared by reaction of an aqueous slurry of yellow mercuric oxide (the red is less reactive) with excess hydrogen cyanide. The mixture is heated to 95°C, filtered, crystallized, isolated, and dried. Its solubihty in water is 10% at 25°C. 

Mercuric o s.ycy2inide[1335-31 -5] or basic mercuric cyanide, Hg(CN)2 HgO, is prepared in the same manner as the normal cyanide, except that the mercuric oxide is present in excess. The oxycyanide is white and crystalline but only one-tenth as soluble in water as the normal cyanide. Because this compound is explosive, it normally is suppHed as a 1 2 mixture of oxycyanide to cyanide. 

The diphenylmaleimide is prepared from the anhydride, 33-87 % yield, and cleaved by hydrazinolysis, 65-75% yield. It is stable to acid (HBr, AcOH, 48 h) and to mercuric cyanide. It is colored and easily located during chromatography, and has been prepared to protect steroidal amines and amino sugars. " ... 

Cyanquecksilber, n. mercury cyanide, -kalium, n. mercury potassium cyanide, -oxyd, n. mercuric cyanide, mercury(II) cyanide. 

Merkuri-. mercuric, mercuri-, mercury(II). Merkuriah en, pi. Pharm.) mercurials. Merkuriahnittel, n. Pharm.) mercurial. Merkuri-ammoniumchlorid, n. mercuriammo-nium chloride, -azetat, n. mercuric acetate, mercury(II) acetate, -chlorid, n. mercuric chloride, mercury(II) chloride, -cyamd, n. mercuric cyanide, mercury(II) cyanide, -cyanwasserstoffs ure, /. mercuricyanic acid, cyanomercuric(II) acid. 

Malonyl dichloride, 33, 20 2-Mercaptobenzimidazole, 30, 56 2-Mercaptobenzoxazole, 30, 57 Mercuric cyanide, 32, 31 Methallyl chloride, 32, 90 MeTHANEPHOSPHORIC ACID, DnSOPRO-PYL ESTER, 31, 33 Methanesulfonic acid, 30, 58 Methaneshlfonyl chloride, 30, 58 Methanol, 30, 31 32, 79 Methone, 31, 40... 

Unlike the behavior of 81, treatment of 2,3,5-tri-O-benzyl-D-ribofuranosyl bromide91 (110) with mercuric cyanide gave an ano-meric mixture of cyanides (111), which was reduced to an epimeric mixture of amines.92 Separation of this mixture by column chromatography gave the D-alio isomer (112), the D-altro isomer (113), and the glycal derivative (114). Compound 112 was, however, formed in moderate yield (18%), presumably because of a preponderance of the a anomer in the mixture of anomeric cyanides (111). Compound 112 was converted92 into the 1-ureido derivative (92) by treatment... 

The primary step in the photolysis of phenyl mercuric cyanide and cyclohexyl mercuric cyanide in methanol at room temperature is mercury-phenyl or mercury-cyclohexyl bond rupture111. The subsequent steps in the mechanism are complex, but do not involve the parent substance. Reactions involving HgCN must be postulated to explain the observed product, so that this radical must have a finite existence. 

The first product of the oxidation of alcohol is acetaldehyde and an important end-product is fulminic add, which latter can, however, only be isolated if silver or mercury ions are present. With these ions it forms salts—fulminates—which are stable towards nitric add in them, it must be presumed, the linkage with the metal is homopolar and non-ionogenic, as in mercuric cyanide. The formation of fulminic acid takes place because the carbonyl group of the aldehyde confers reactivity on the adjacent methyl group which then forms a point of attack for the nitrous acid. The various stages in the process are indicated by the following formulae ... 

Mercuric cyanide Unknown s Sodium arsenite Unknown s... 

In 1803 WiUiam Hyde Wollaston (1776—1828), an Enghsh chemist who also discovered rhodium, isolated palladium at the time he analyzed the platinum and gold ores sent to him from Brazil. Dissolving the platinum in aqua reg)a acid, Wollaston then treated the residue with mercuric cyanide to produce the compound of palladious cyanide that was reduced by burning it to extract metallic palladium. 

Cyanogen also may be prepared by the reaction of mercuric cyanide with mercuric chloride. Dry cyanogen gas may be obtained by this process ... 

Palladium was discovered in 1803 by W.H. Wollaston during refining and purification oP platinum metal. This new metal was found in the aqua regia extract of native platinum and was detected in solution after platinum was precipitated. It was removed as ammonium chloroplatinate. Treating this solution with mercurous cyanide precipitated a yellow palladium complex salt. The precipitate was washed and ignited to form palladium metal. Wollaston named the element palladium after the newly discovered asteroid Pallas. 

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