Mercury arsine complexes

Ligand exchange reactions have been used to prepare mercury(II) trialkylarsine complexes.202 Reaction of AgN03-AsMe3 with mercury halides gave the mercury arsine and silver halide (equations 10 and 11). The silver nitrate complex was not characterized. 

Chelate complexes could only be prepared in the case of platinum(II) as the metal ion, while the group V atom alone acted as a donor toward palladium(II) and mercury(II). The coordinated olefin in the chelate complexes was found to be readily displaced by monodentate ligands such as tertiary arsines, -toluidine and the thiocyanate ion. It was suggested by these workers that chelation would take place more readily if the olefinic phosphine or arsine were subject to greater steric restrictions than was the pentenyl ligand. 

N-(2,3-Dimercaptopropyl)phthalamidic acid (41, DMPA) has been shown to form relatively stable complexes with cadmium, zinc and mercury312. DMPA has also been shown to enhance faecal and urinary excretion of mercury in mice and arsenic in mice and rabbits. For the decorporation of arsenic, taken in as arsine, the administration of 3-(tolylthio)propane-l, 2-dithiol (42) has been proposed in the USSR313. ... 

Interferences Metals or salts of metals such as chromium, cobalt, copper, mercury, molybdenum, nickel, palladium, and silver may interfere with the evolution of arsine. Antimony, which forms stibine, is the only metal likely to produce a positive interference in the color development with the silver diethyldithiocarbamate. Stibine forms a red color with silver diethyldithiocarbamate that has a maximum absorbance at 510 nm, but at 535 to 540 nm, the absorbance of the antimony complex is so diminished that the results of the determination would not be altered significantly. 

Tellurium coordination is seen in a series of acychc bidentate ligands that coordinate through Te N donor atoms or Te donor atoms An interesting series of adamantane-like cage complex cations that contain mercury(II) have been prepared and have the general formula [ j,-ER2(HgL)4] + (E = S, Se,orTe L = phosphine or arsine). These cations contain a variety of Hg-L bonds and have been characterized using heteronuclear NMR ( P, Te, Hg). 

Neither of these metalloporphyrins has been found in crude oil, however. Mercury forms porphyrin complexes with mesoporphyrin but the complexes are decomposed by water. The extraction of crude oil C-1 with distilled water removed insignificant amounts of Hg, thus indicating that Hg is not present in the oil as a porphyrin complex. Arsenic also shows a higher concentration in the low-molecular-weight fraction than in the 1000-4000 fraction. This is consistent with the previous conclusion that part of the As in crude oil is present in low-molecular-weight compounds such as alkyl or aryl arsines. 

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