Mercuric cyanide, reaction

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. 

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. 

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

CuCN (aq.). Varet3 measured the heat of reaction of cuprous iodide with aqueous mercuric cyanide. 

Quaternization of the sulfur atom followed by reaction with mercuric cyanide produces the corresponding 2-aminomalononitrile.64171... 

Palladium Cyanide, Pd(CN)2, was known to Berzelius,3 who obtained it by decomposition of a palladium salt with mercuric cyanide. It also results when palladium oxide is boiled with a solution of mercuric cyanide. These reactions afford a useful method of separating palladium from its congeners. When heated in air cyanogen is evolved and spongy palladium left. 

Mercuric cyanide, Hg(CN)2, precipitates palladous cyanide, Pd(CN)2, from solution in the form of a yellowish white, gelatinous deposit, which is readily soluble in potassium cyanide, as also in ammonium hydroxide. This reaction is unique amongst the platinum metals, and serves as the basis of a useful method of separating and estimating palladium. 

The reaction with the heavy metal cyanides may be brought about either by treating diphenyl chloroarsine at 150° to 160° C. for 3 hours with dry, recently prepared silver cyanide, or by the treatment of diphenyl arsenious sulphide with mercuric cyanide for 2 hours at 160° to 200° C. ... 

Silver cyanide does not give such satisfactory results in this reaction as mercuric cyanide. ... 

Replacing mercuric cyanide by silver cyanide in this reaction only decreases the yield by 2 per cent. 

Cyclopentadiene reacts with mercuric cyanide in aqueous solution, giving the insoluble cream compound CsHsHgCN. Like the corresponding iodide (which is also cream) this compound is fairly stable in air, but does not melt sharply (62). By the reaction of indenyl lithium and mercuric chloride in dry ether, indenyl mercuric bromide (the bromine being... 

A similar product is formed when acetone and mercuric cyanide react in presence of sodium hydroxide, and the reaction may occur according to the equation ... 

The complexity of the reaction is illustrated by the yields of methyl tetra-0-acetyl-/3-D-glucopyranoside obtained when the appropriate a-gly-cosyl bromide was shaken with pure methanol (50 moles) at room temperature in the presence of mercuric cyanide. After 30 minutes, the yield was 64%), rising to 89 %o after 40 mins., and falling to 12% after 100 min. Reacetylation after 150 min. brought the yield up to 80 %, suggesting that there had been deacetylation after condensation. 

Diphenylacetonitrile has been prepared by the dehydration of diphenylacetamide, " by the reaction of diphenylbromomethane and mercuric cyanide, by the reaction of diphenylacetic acid and lead thiocyanate, and by the removal of ammonia from diphenyl-acetamidine. The present method is a modification of that of Hoch.ii... 

Color reactions Boric acid (hydroxyquinones). Dimethylaminobenzaldehyde (pyrroles). Ferric chloride (enols, phenols). Haloform test. Phenylhydrazine (Porter-Silber reaction). Sulfoacetic acid (Liebermann-Burchard test). Tetranitromethane (unsaturation). Condensation catalysts /3-Alanine. Ammonium acetate (formate). Ammonium nitrate. Benzyltrimethylammonium chloride. Boric acid. Boron trilluoride. Calcium hydride. Cesium fluoride. Glycine. Ion-exchange resins. Lead oxide. Lithium amide. Mercuric cyanide. 3-Methyl-l-ethyl-2-phosphoiene-l-oxlde. 3-Methyl-1-phenyi-3-phoipholene-1-oxide. Oxalic acid. Perchloric acid. Piperidine. Potaiaium r-butoxIde. Potassium fluoride. Potassium... 

---