Mercurous chloride . See

Most of the information on this subject refers to solvent effects on the substitution of tetraalkyltins by mercuric chloride (see Chapter 6, Section 1.5, p. 70) and to the iododemetallation of tetraalkyltins and tetraalkylleads (see Chapter 8, Section 6, p. 173). Data on solvent effects for a number of reactions are summarised in Table 12. There is only a partial correlation of the rate coefficients with any of the usual parameters51 of solvent polarity in particular, the solvents acetonitrile and acetone increase the value of the various rate coefficients to a much greater extent than would be predicted on the basis of solvent dielectric constant (e), or Z values, or 2sT values, etc.51. This may be seen especially for the iododemetallation of tetramethyllead, reaction (6) (R = Me)... 

Inorganic mercury, such as occurs in mercury salts, is mostly soluble or dispersible in water and therefore would disperse in the environment. At high levels it would certainly be poisonous to wildlife and humans alike but, dispersed in large volumes of water, it would be less of a risk. Under certain conditions, however, inorganic mercury may give rise to organomercury (see below). Inorganic mercury has been used in medicine as a laxative and to treat syphilis in the form of calomel (mercurous chloride) (see case notes). Corrosive sublimate (mercuric chloride) was used as a disinfectant and some traditional Chinese medicines stHl contain it. 

METHOXYETHYL MERCURIC ACETATE see MEO750 METHOXYETHYL MERCURIC ACETATE see MEO750 METHOXYETHYL MERCURIC CHLORIDE see MEP250... 

Benzoylmethyl-mercuric chloride.— The above compound in hot 95 per cent, alcohol is heated with mercuric chloride until the mixture no longer gives a test for mercuric ions when treated with sodium hydroxide. The mixture, after dilution and cooling in ice, gives a precipitate melting at 146° C. This compound is identical with that prepared by the direct mercuration of acetoj)henone, ix, phenacyl-mercuric chloride, see p. 196. 

Aqueous solutions of polyoxyl 35 castor oil (Cremophor EL and Cremophor ELF) are stable in the presence of low concentrations of electrolytes such as acids or salts, with the exception of mercuric chloride see Section 12. 

Another expedient is to add thiophenol to the double bond and then hydrolyze the resultant thioacetal with mercuric chloride (see 5, 85). 

One of the first anion-directed assemblies is the [12]mer-curacarborand-4 (1) reported by Hawthorne in 1991. which can be prepared in high yields by reacting 1,2-dilithio-carborane with mercuric chloride (see Fig. 1). " This compound consists of four bivalent 1 2-carborane cages linked by four mercury atoms forming a macrocycle with a chloride ion located at its center. The anion displays strong Lewis-acid-base interactions with the four mercury atoms of the macrocycle. Such interactions play an important role in directing the formation of the cyclic... 

Mercuric arsenate. See Mercury arsenate (ic) Mercuric bichloride Mercuric chloride. See Mercury chloride (ic)... 

Mercurothiolate. See Thimerosal Mercurous chloride. See Mercury chloride (ous) Dimercury dichloride Mercury... 

It is important to preserve samples of waste water, particularly for determining cyanide, phenol, organic compounds and nitrogen compounds, etc. (e.g. with chloroform, by alkalization or with mercuric chloride) (see 1.7). 

A common example is the activation of magnesium by mercuric chloride. See Wakefield, B.J. Organomagnesium Methods in Organic Synthesis, Academic Press, London, 1995. 

Many mercury compounds are labile and easily decomposed by light, heat, and reducing agents. In the presence of organic compounds of weak reducing activity, such as amines (qv), aldehydes (qv), and ketones (qv), compounds of lower oxidation state and mercury metal are often formed. Only a few mercury compounds, eg, mercuric bromide/77< 5 7-/7, mercurous chloride, mercuric s A ide[1344-48-5] and mercurous iodide [15385-57-6] are volatile and capable of purification by sublimation. This innate lack of stabiUty in mercury compounds makes the recovery of mercury from various wastes that accumulate with the production of compounds of economic and commercial importance relatively easy (see Recycling). 

The second method of preparation involves precipitation from a cold acidic solution of mercurous nitrate. Mercurous chloride is isolated after washing in a manner similar to the chamber method described. This product, which generally contains small amounts of occluded sodium nitrate, is satisfactory as a technical-grade material. Difficulty may be encountered in having it pass NF or reagent-grade specifications (see Fine chemicals). 

Catalytic amounts of mercuric chloride are usually employed in this preparation. Aluminum isopropoxide is a useful Meerwein-Potmdorf-Verley reducing agent in certain ester-exchange reactions and is a precursor for aluminum glycinate, a buffering agent (see Alkoxides, metal). 

MERCURIC CHLORIDE, AMMONIATED see MERCURY AMMONIUM CHLORIDE ... 

The exchange of aromatic protons can be effected in the absence of any -OH or —NH2 activating group during the course of a Clemmensen reduction in deuteriochloric and deuterioacetic acid mixture (see section Ill-D). This reaction has been carried out with various tricyclic diterpenes and is best illustrated by the conversion of dehydroabietic acid into its 12,14-d2-labeled analog (40 -+ 41).Amalgamated zinc is reportedly necessary for the exchange reaction since the results are less satisfactory when a zinc chloride-mercuric chloride mixture is used. 

We return now to the mercuro-de-diazoniation. Nesmeyanov s school continued the work on metallo-de-diazoniations from 1929 to 1953 (see summary by Nesmeyanov, 1972). A major discovery was made at the very beginning, namely the influence of copper powder (Nesmeyanov, 1929 b Nesmeyanov and Kahn, 1929). With this addition metallic mercury was not required instead the double salt of the diazonium chloride and mercuric chloride was used. The copper reacts stoichiometrically as an electron donor. Therefore, either arylmercuric chlorides (Scheme 10-87) or diarylmercury compounds (Scheme 10-88) can be obtained. These reactions are called Nesmeyanov reactions. Specific examples are the syntheses of di-2-naphthyl-... 

Mercuric chloride, other mercury-containing antibacterials and silver will inhibit enzymes in the membrane, and for that matter in the cytoplasm, which contain thiol, -SH, groups. A similar achon is shown by 2-bromo-2-nitropropan-l,3-diol (bronopol) and iso-thiazolones. Under appropriate condihons the toxic action on cell thiol groups may be reversed by addition of an extrinsic thiol compound, for example cysteine or thioglycollic aeid (see also Chapters 12 and 23). 

Tin Amalgam. To a solution of 15 g of mercuric chloride in 100 ml of water, add 100 g of 30 mesh tin metal while stirring briskly. Let set for a few seconds after several min of stirring to see if the tin has acquired a shiny coating of mercury if not, stir or shake for 30 sec. more and check again. Decant the liquid and wash the tin amalgam until the washings are clear. This can be stored under distilled water for a moderate amount of time. 

Copper nitrate and mercuric nitrate when heated with the aqueous solution give a black precipitate of the corresponding sulphide mercuric chloride in excess causes the precipitation of the white substance 2HgS.HgCl2 (see p. 206) silver nitrate produces a white precipitate which gradually becomes black due to the formation of sulphide.4... 

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