Mercury organo- compounds

Numerous new salts and additive compounds of cinchona alkaloids, and especially of quinine, have been described, of which only a few can be mentioned as examples quinine additive compounds with sulph-anilamide, t quinine salts of (+) and (—)-pantothenic acid, °( > quinine sulphamate and disulphamate, °( organo-mercury compounds of quinine and cinchonine such as quinine-monomercuric chloride. Various salts and combinations of quinine have also been protected by patent, e.g., ascorbates and nicotinates. 

There is a vast range of aqueous organic pollutants with a wide toxicity profile. Some, e.g. polychlorinated biphenyls, certain herbicides, fungicides and pesticides, and organo-mercury compounds, are persistent and may bioaccumulate in the food chain. Trace contaminants such as sodium chloride, iron and phenols (especially if chlorinated) may also impart a taste to water. Typical consent levels for industrial discharges are provided in Table 13.10. 

Gel2 also reacts with organo-mercury compounds 131 ... 

In many syntheses activation is not effected by sonochemical preparation of the metal alone but rather by sonication of a mixture of the metal and an organic reagent(s). The first example was published many years ago by Renaud, who reported the beneficial role of sonication in the preparation of organo-lithium, magnesium, and mercury compounds [86]. For many years, these important findings were not followed up but nowadays this approach is very common in sonochemistry. In another early example an ultrasonic probe (25 kHz) was used to accelerate the preparation of radical anions [87]. Unusually for this synthesis of benzoquinoline sodium species (5) the metal was used in the form of a cube attached to the horn and preparation times in diethyl ether were reduced from 48 h (reflux using sodium wire) to 45 min using ultrasound. 

Toxicology. Organo (alkyl) mercury compounds cause dysfunction of the central nervous system (CNS) and kidneys and are irritants of the eyes, mucous membranes, and skin methyl mercury causes developmental effects in humans. 

Transition metal compounds with covalent carbon-metal bonds include organo-zinc, organo-cadmium, and organo-mercury compounds. Carbon-13 shifts of the methyl derivatives (Table 4.71) indicate a heavy atom deshielding. Diphenylmercury displays carbon shifts similar to those of phenyllithium and phenylmagnesium bromide (Table 4.53). 

Cognate preparation. 1-Phenylethanol. Use 10.4g (11.5ml, 0.1 mol) of styrene, and carry out the oxymercuration and reduction as described above. The yield of recovered mercury is 17.5 g (87%), and traces continue to separate during the work-up procedure. Distil the final crude product under reduced pressure and collect the 1-phenylethanol at 110-115 °C/25mmHg. Towards the end of the distillation the decomposition of residual organo-mercurial compounds ensues, and co-distillation of mercury contaminates the product collect the contaminated fraction separately. The first fraction, yield 6.2 g (51%), is 92 per cent pure by g.l.c. (retention time 5.33 minutes) the impurity is mainly styrene (tR 2.16 minutes). The mercury-contaminated fraction (3.0 g, 25%) is 85 per cent pure by g.l.c. 

Kochetkov continued as lecture assistant until 1951, combining this work with research on metalloorganic chemistry in Nesmeyanov s laboratory. He studied organo-mercury compounds, in particular their synthesis by the addition of mercuric chloride to acetylenes. In 1948 Nikolay wrote a thesis and received the Ph.D. degree in chemistry. 

The preparation of organopalladium compounds by exchange reactions of palladium salts and organo-lead, -tin, or -mercury compounds is apparently not the only way that they can be obtained but it does seem to be the most useful way. Convincing evidence is now available to show that direct metalation of aromatic compounds with palladium salts (palladation) can occur. Since the initial report of Cope and Siekman 32> that palladium chloride reacted readily with azobenzene to form an isolable chelated, sigma-bonded arylpalladium compound, several additional chelated arylpalladium compounds have been prepared. 

Y. Talmi, The rapid sub-picogram determination of volatile organo-mercury compounds by gas chromatography with a microwave emission spectrometric detector system, Anal. Chim. Acta, 74 (1975), 107-117. 

Many other household products can be analysed in similar ways to those described above for chemicals. Household bleach is essentially an inorganic chemical. There has been concern expressed about mercury levels in hypochlorite bleach because of the way it is manufactured. The cold vapour reduction/aeration method referred to above is a good way of determining low mercury levels with minimal matrix problems [82]. In the past organo-mercurial compounds have been used (e.g. as bactericides) in some household products these may be selectively determined by extraction with an organic solvent (e.g. carbon tetrachloride or benzene), and then application of the cold-vapour method following the addition of cysteine acetate, or by coupled gas chromatography/atomic absorption [83],... 

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