1184-57-2Relevant articles and documents
A Long-Path Fourier Transform Infrared Study of the Kinetics and Mechanism for the HO-Radical Initiated Oxidation of Dimethylmercury
Niki, H.,Maker, P. D.,Savage, C. M.,Breitenbach, L. P.
, p. 4978 - 4981 (1983)
Gaseous and aerosol products formed in the HO-radical initiated reaction of CH3HgCH3 were studied by the long-path FT IR method in the photolysis of CH3HgCH3-C2H5ONO-NO mixtures typically at 10, 10, and 20 ppm each in 700 torr of air at ca. 300 K.The results were consistent with the predominant occurence of the displacement reaction of HO + CH3HgCH3 -> CH3HgOH + CH3 as the primary process.The relative rate constant for the HO-radical reactions of CH3HgCH3 and C2H4 was determined to be k(C3H4)/k(CH3HgCH3) = 0.43 +/- 0.03(?).This value combined with the literature value of k(C2H4) = (8.48 +/- 0.39) X 10-12 cm3 molecule-1 s-1.
A Raman spectroscopic study of the complexation of the methylmercury(II) cation by amino acids
Alex, Serge,Savoie, Rodrigue
, p. 491 - 496 (2007/10/02)
A systematic Raman spectroscopic investigation of the complexation of CH3Hg(1+) by the standard amino acids is reported.It is shown that the vibrational bands due to the ligand-Hg and Hg-CH3 stretching modes and to the symmetric -CH3 bending mode of the -HgCH3 unit are well suited to characterize the extent of complexation and the sites of attachment of the cation.Coordination, which occurs mostly on sulfur and nitrogen atoms by substitution of a proton on the thiol group of cysteine or on amino groups in general, is best identified by the frequency of the ligand-Hg stretching vibration in the 250-550 cm-1 region of the spectrum.
Nuclear magnetic resonance studies of the solution chemistry of metal complexes. XVII. Formation constants for the complexation of methylmercury by sulfhydryl-containing amino acids and related molecules
Reid, R. Stephen,Rabenstein, Dallas L.
, p. 1505 - 1514 (2007/10/02)
Complexation of methylmercury, CH3Hg(II), by mercaptoacetic acid, mercaptoethanol, mercaptosuccinic acid, cysteine, penicillamine, homocysteine, and N-acetylpenicillamine has been studied by 1H nuclear magnetic resonance spectroscopy.The equilibrium constant for displacement of mercaptoacetic acid from its CH3Hg(II) complex by each of the other thiols was measured over a wide range of pH.From the displacement constants and a literature value for the formation constant of the mercaptoethanol complex of CH3Hg(II), formation constants were calculated for thiol complexes with the other ligands, including microscopic formation constants for cysteine and penicillamine complexes in which the amino groups are protonated and deprotonated.Detailed information on the acid-base chemistry of the free amino and carboxylic acid groups in the complexes is also reported.The formation constants increase as the Bronsted basicity of the deprotonated sulfhydryl group increases according to the relation logKf = pK + 6.86 .The conditional formation constants of the CH3Hg(II) complexes are strongly pH dependent due to competitive reactions involving hydrogen and hydroxide ions at low and high pH.The results at physiological pH are discussed with reference to the effectiveness of mercaptosuccinic acid, N-acetylpenicillamine, and penicillamine as antidotes for methylmercury poisoning.
