Methylmercury cyanide

In an admirable microwave study of methylmercury cyanide, H3CHgCN (five isotopomers), the structural parameters have been obtained with high precision (data for substitution structure rs(H3C—Hg) 205.63(1), rs(Hg—CN) 203.69(2), rs(C—N) 115.70(2) pm) the dipole moment is high, M = 4.69(4) D.108... 

Steig, S. (1997) A miniature membrane tube for rapid parallel distillation of cyanide, phenolics, ammonia, sulfide, methylmercury and tritium from waters and solids. Am. Environ. Lab., 9, 10-11. 

Human activities have resulted in the release of a wide variety of both inorganic and organic forms of mercury. The electrical industry, chloro-alkali industry, and the burning of fossil fuels (coal, petroleum, etc.) release elemental mercury into the atmosphere. Metallic mercury has also been released directly to fresh water by chloro-alkali plants, and both phenylmer-cuiy and methylmercury compounds have been released into fresh and sea water -phenylmercury by the wood paper-pulp industry, particularly in Sweden, and methyl-mercury by chemical manufacturers in Japan. Important mercury compounds which also may be released into the environment include mercury(II) oxide, mercury(II) sulfide (cinnabar), mercury chlorides, mer-cury(II) bromide, mercury(II) iodine, mer-cury(II) cyanide, mercury(II) thiocyanate, mercury(II) acetate, mercury nitrates, mercury sulfates, mercury(II) amidochloride monoalkyl- and monoarylmercury(II) halides, borates and nitrates dialkylmercury compounds like dimethylmercury, alkoxyal-kylmercury compounds or diphenylmercury (Simon and Wiihl-Couturier 2002) (for quantities involved, see Section 17.4). 

Transformation of methylmercury chloride to bromide, iodide or cyanide. Shake a benzene solution of methylmercury chloride with excess hydrobromic acid, potassium iodide or potassium cyanide in dilute aqueous solution. Dry the benzene layers with sodium sulphate and concentrate them by evaporation under reduced pressure. 

The bromide, iodide and cyanide from the fish extracts moved as methylmercury bromide, iodide, and cyanide (Figure 11) when... 

Fig. 11. Thin-layer chromatogram on silica gel of authentic methyl-mercurychloride (1), iodide (3), bromide (5), and cyanide (7) together with the corresponding compounds prepared from methylmercury chloride extracted from pike (2,4,6,8)...

By heating in 0.1 M HCl the carbon-cobalt bond of adenosylcobalamin is cleaved the alkylcobalamins are relatively stable in dilute acid or alkali. Cyanide forms another threat to the adenosyl-cobalt bond, in particular at alkaline pH and at elevated temperature, by inducing dicyanocobalamin. The alkylcorrinoids are more resistant to the effect of cyanide, but are spliced through electrophilic attacks on the methyl group, for instance by ionic mercury or thallium, into aquocobalamin and the methylmercury cation, or the methylthallic dication (29). 

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