Methylmercuric salts

Refs l)Mellor 11(1931), 274-5 2)Ullmann 5 (1953), 587 3)Sax(l957), 842 4)Lange(1961), 266-7 5)Gmelin Syst Nr 52(l962ff) Methylmercuric Chromate. See Methylmercuric Salts under M... 

Tables 7-10 contain data only for alkyls of non-transition metals (Zn, Cd, and Hg have completely filled -shells), but Gregory and Ingold19 have determined rate coefficients for cleavage of Me-Au and Et-Au bonds by mercuric salts and methylmercuric salts. Relative rate coefficients are given in Table 11. Gregory and Ingold suggested that the reactions of RAuPPh3 with mercuric salts in solvent dioxan (e = 2.1) proceeded by mechanism SE2(open), a conclusion which if correct would be in conflict with the hypotheses of Gielen and Nasielski44 and of Abraham...

Bache, C. A., Lisk, D. J. Gas chromatographic determination of organic mercury compounds by emission spectrometry in a helium plasma. Application to the analysis of methylmercuric salts in fish. Anal. Chem. 43, 950 (1971). 

Mercuric carboxylates, which decarboxylate by a chain mechanism when initiated by peroxides, also decarboxylate under UV irradiation (123,128,129,131-140,142,144-146,153-155). In addition, decarboxylation was observed for mercuric benzoate and mercuric a-naphthoate (123). Side reactions [Eqs. (24), (25), (109)] observed in peroxide initiated reactions also occurred on UV irradiation, and mercurous salt formation [Eq.(24)] was more extensive under the latter conditions. Decarboxylation giving methylmercuric acetate occurred on irradiation of mercuric acetate in aqueous solution and is considered to be of environmental significance (156,157). Stepwise decarboxylation giving (CF3)2Hg occurred on irradiation of solid mercuric trifluoroacetate at -196° C (158), but, at 20° C, trifluoromethyl radicals diffused from the solid and dimerized (158). No other diorganomercurial has been formed by radical decarboxylation, and the reaction is not preparatively competitive with the thermal decarboxylation synthesis of (CF3)2Hg (26,27) (Section III,A). 

In solvent DMSO, the rate of reaction (17) (R = Me, X = Cl) was too fast to follow, but using the mixture DMSO-dioxan (1 9 v/v) at 24.7 °C, rate coefficients for the substitution of the gold(I) complex by several alkylmercuric salts were obtained. It was found that in this mixed solvent, reaction (17) followed first-order kinetics, first-order in the gold(I) complex and zero-order in the alkylmercuric salt. Furthermore, the first-order rate coefficient had the same value no matter what alkylmercuric salt was used (methylmercuric acetate, methylmercuric chloride, methylmercuric bromide, and ethylmercuric chloride were the salts used). At 24.7 °C, the first-order rate coefficient has the value 0.0083 sec-1, with a standard deviation of 0.0006 sec-1. 

SYNS ARETAN-NIEinOC B 4992 BIS-(METHYD MERCURY)-SULFATE BIS-(METHYLMERKURI)-SULFAT CERESAN UNIVERSAL-FEUCHTBEIZE CEREWET COMPOUND-4992 MERCURY, SULFATOBIS(METHYL- METHYLMERCURIC SULFATE SULFURIC ACID, BIS(METHYLMERCURY) SALT... 

In vitro evidence suggests that organic mercury is also readily absorbed in the gastrointestinal tract and that methylmercuric chloride is absorbed to a greater extent than phenylmercuric chloride (Endo et al. 1989). Complexing of methylmercury with nonprotein sulfhydryls also may play a role in intestinal absorption and reabsorption (Urano et al. 1990). Phenylmercuric salt in the diet was completely... 

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