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Organomercury
Organomercury refers to the group of organometallic compounds that contain mercury. Typically the Hg–C bond is stable toward air and moisture but sensitive to light. Important organomercury compounds are the methylmercury(II) cation, CH3Hg+; ethylmercury(II) cation, C2H5Hg+; dimethylmercury, (CH3)2Hg, diethylmercury and merbromin ("Mercurochrome"). Thiomersal is used as a preservative for vaccines and intravenous drugs. The toxicity of organomercury compounds presents both dangers and benefits. Dimethylmercury in particular, is notoriously toxic, but found use as an antifungal agent and insecticide. Merbromin and phenylmercuric borate are used as topical antiseptics, while nitromersol is used as a preservative for vaccines and antitoxins. Synthesis Organomercury compounds are generated by many methods, including the direct reaction of hydrocarbons and mercury(II) salts. In this regard, organomercury chemistry more closely resembles organopalladium chemistry and contrasts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury (element)
Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver and was formerly named hydrargyrum ( ) from the Greek words, ''hydor'' (water) and ''argyros'' (silver). A heavy, silvery d-block A block of the periodic table is a set of elements unified by the atomic orbitals their valence electrons or vacancies lie in. The term appears to have been first used by Charles Janet. Each block is named after its characteristic orbital: s-blo ... element, mercury is the only metallic element that is known to be liquid at standard temperature and pressure; the only other element that is liquid under these conditions is the halogen bromine, though metals such as caesium, gallium, and rubidium melt just above room temperature. Mercury occurs in deposits throughout the world mostly as cinnabar (mercuric sulfide). The red pigment vermilion is obtained by Mill (grinding), grinding natural cinnabar or synthetic mercuric sulfide. Mercury is used in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethylmercury
Ethylmercury (sometimes ethyl mercury) is a cation composed of an organic CH3CH2- species (an ethyl group) bound to a mercury(II) centre, making it a type of organometallic cation, and giving it a chemical formula C2H5Hg+. The main source of ethylmercury is thimerosal. Synthesis and structure Ethylmercury (C2H5Hg+) is a substituent of compounds: it occurs as a component of compounds of the formula C2H5HgX where X = chloride, thiolate, or another organic group. Most famously X = the mercaptide group of thiosalicylic acid as in thiomersal. In the body, ethylmercury is most commonly encountered as derivatives with a thiolate attached to the mercury. In these compounds, Hg(II) has a linear or sometimes trigonal coordination geometry. Given the comparable electronegativities of mercury and carbon, the mercury-carbon bond is described as covalent. Toxicity The toxicity of ethylmercury is well studied. Like methylmercury, ethylmercury distributes to all body tissues, crossing t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimethylmercury
Dimethylmercury (( C H3)2 Hg) is an extremely toxic organomercury compound. A highly volatile, reactive, flammable, and colorless liquid, dimethylmercury is one of the strongest known neurotoxins, with a quantity of less than 0.1 mL capable of inducing severe mercury poisoning resulting in death, and is easily absorbed through the skin. Dimethylmercury is capable of permeating many materials, including plastic and rubber compounds. It has a slightly sweet odor. Synthesis, structure, and reactions The compound was one of the earliest organometallics reported, reflecting its considerable stability. The compound was first prepared by George Buckton in 1857 by a reaction of methylmercury iodide with potassium cyanide: : 2 CH3HgI + 2 KCN → Hg(CH3)2 + 2 KI + (CN)2 + Hg Later, Frankland discovered that it could be synthesized by treating sodium amalgam with methyl halides: : Hg + 2 Na + 2 CH3I → Hg(CH3)2 + 2 NaI It can also be obtained by alkylation of mercuric chloride with meth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiomersal
Thiomersal (INN), or thimerosal (USAN, JAN), is an organomercury compound. It is a well-established antiseptic and antifungal agent. The pharmaceutical corporation Eli Lilly and Company gave thiomersal the trade name Merthiolate. It has been used as a preservative in vaccines, immunoglobulin preparations, skin test antigens, antivenins, ophthalmic and nasal products, and tattoo inks. In spite of the scientific consensus that fears about its safety are unsubstantiated, its use as a vaccine preservative has been called into question by anti-vaccination groups. Due to this public pressure the substance was phased out of routine childhood vaccines in the United States, the European Union, and a few other countries in response to popular fears. It remains in use as a preservative for annual flu vaccines. History Morris Kharasch, a chemist then at the University of Maryland filed a patent application for thiomersal in 1927; Eli Lilly later marketed the compound under the trade ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitromersol
Nitromersol (metaphen) is a mercury-containing organic compound that is primarily used as an antiseptic and disinfectant. It is a brown-yellow solid that has no odor or taste, does not irritate the skin or mucous membranes, and has no impact on rubber or metallic instruments, including surgical and dental tools. This compound is a confirmed animal carcinogen. It can emit toxic fumes of NOx and mercury vapor when heated. In 1998, use of nitromersol (and other mercury-containing products) as OTC first-aid antiseptics and products for diaper rash and vaginal contraceptives was disallowed by the FDA. Nitromersol can cause hypersensitivity reactions. It is still in use as a preservative for vaccines and antitoxins. See also * * Phenylmercuric nitrate Phenylmercuric nitrate is an organomercury compound with powerful antiseptic and antifungal effects. It was once commonly used as a topical solution for disinfecting wounds, but as with all organomercury compounds it is highly to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylmercury
Methylmercury (sometimes methyl mercury) is an organometallic cation with the formula . It is the simplest organomercury compound. Methylmercury is extremely toxic, and its derivatives are the major source of organic mercury for humans. It is a bioaccumulative environmental toxicant. Structure and chemistry "Methylmercury" is a shorthand for the hypothetical "methylmercury cation", sometimes written "''methylmercury(1+) cation''" or "''methylmercury(II) cation''". This functional group is composed of a methyl group bonded to an atom of mercury. Its chemical formula is (sometimes written as ).The Methylmercury compound has an overall charge of +1, with Hg in the +2 oxidation state.Methylmercury exists as a substituent in many complexes of the type (L = Lewis base) and MeHgX (X = anion). As a positively charged ion it readily combines with anions such as chloride (), hydroxide () and nitrate (). It has particular affinity for sulfur-containing anions, particularly thiols (). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diethylmercury
Diethylmercury is a flammable, colorless liquid, and one of the strongest known neurotoxins. This organomercury compound is described as having a slightly sweet smell, though inhaling enough fumes to notice this would be hazardous. This chemical can cross the blood–brain barrier, causing permanent brain damage. It is, however, considerably less toxic than dimethylmercury. Synthesis Diethylmercury can be obtained from the reaction between ethylmagnesium bromide and mercury(II) chloride. :2 C2H5MgBr + HgCl2 → Hg(C2H5)2 + MgBr2 + MgCl2 Other methods are also known. See also * Dimethylmercury, a related compound * Ethylmercury * Mercury poisoning Mercury poisoning is a type of metal poisoning due to exposure to mercury. Symptoms depend upon the type, dose, method, and duration of exposure. They may include muscle weakness, poor coordination, numbness in the hands and feet, skin rashe ... References {{DEFAULTSORT:Diethyl Mercury Organomercury compounds Sweet-sme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Merbromin
Merbromin (marketed as Mercurochrome, Merbromine, Mercurocol, Sodium mercurescein, Asceptichrome, Supercrome, Brocasept and Cinfacromin) is an organomercuric disodium salt compound used as a topical antiseptic for minor cuts and scrapes and as a biological dye. Readily available in most countries, it is no longer sold in Switzerland, Brazil, France, Iran, Germany, or the United States due to its mercury content. Uses Merbromin's best-known use is as a topical antiseptic to treat minor wounds, burns, and scratches. It is also used in the antisepsis of the umbilical cord and the antisepsis of wounds with inhibited scar formation, such as neuropathic ulcers and diabetic foot sores. When applied on a wound, it stains the skin a distinctive carmine red, which can persist through repeated washings. Due to its persistence and to its lethality to bacteria as an antiseptic, Merbromin is useful on infections of the fingernail or toenail. The U.S. Food and Drug Administration in 1998 r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenylmercuric Borate
Phenylmercuric borate is a topical antiseptic and disinfectant that is soluble in water, ethanol and glycerol. It was used until the 1990s as an active ingredient in disinfectants and in the field of wound treatment for the skin, mouth and throat, for example under the trade name ''Merfen Orange''. However, it has been replaced by other substances due to the high mercury content. See also * Phenylmercuric nitrate Phenylmercuric nitrate is an organomercury compound with powerful antiseptic and antifungal effects. It was once commonly used as a topical solution for disinfecting wounds, but as with all organomercury compounds it is highly toxic, especially ... References Antiseptics Borates Organomercury compounds Phenyl compounds {{dermatologic-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organometallic Chemistry
Organometallic chemistry is the study of organometallic compounds, chemical compounds containing at least one chemical bond between a carbon atom of an organic molecule and a metal, including alkali, alkaline earth, and transition metals, and sometimes broadened to include metalloids like boron, silicon, and selenium, as well. Aside from bonds to organyl fragments or molecules, bonds to 'inorganic' carbon, like carbon monoxide (metal carbonyls), cyanide, or carbide, are generally considered to be organometallic as well. Some related compounds such as transition metal hydrides and metal phosphine complexes are often included in discussions of organometallic compounds, though strictly speaking, they are not necessarily organometallic. The related but distinct term " metalorganic compound" refers to metal-containing compounds lacking direct metal-carbon bonds but which contain organic ligands. Metal β-diketonates, alkoxides, dialkylamides, and metal phosphine complexes are repres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organolithium Compound
In organometallic chemistry, organolithium reagents are chemical compounds that contain carbon–lithium (C–Li) bonds. These reagents are important in organic synthesis, and are frequently used to transfer the organic group or the lithium atom to the substrates in synthetic steps, through nucleophilic addition or simple deprotonation. Organolithium reagents are used in industry as an initiator for anionic polymerization, which leads to the production of various elastomers. They have also been applied in asymmetric synthesis in the pharmaceutical industry. Due to the large difference in electronegativity between the carbon atom and the lithium atom, the C−Li bond is highly ionic. Owing to the polar nature of the C−Li bond, organolithium reagents are good nucleophiles and strong bases. For laboratory organic synthesis, many organolithium reagents are commercially available in solution form. These reagents are highly reactive, and are sometimes pyrophoric. History and deve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
