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Organomercury
Organomercury chemistry refers to the study of organometallic compounds that contain mercury. Many organomercury compounds are highly toxic, but some are used in medicine, e.g., merbromin ("Mercurochrome") and the vaccine preservative thiomersal. Structure and bonding Most organomercury compounds feature diamagnetic Hg(II) and adopt a linear C-Hg-X structure. Indeed, no organic derivatives of Hg are known, as Hg requires electronegative subtituents for condensed-phase stability. Hg(II) derivatives are neither Lewis basic or Lewis acidic. They are stable to oxygen and water, indicating the low polarity of the Hg-C bond. Mercury forms a compound with two cyclopentadiene ligands, but the resulting complex may not be a metallocene. When made in the 1950s, it was too sensitive for structural determination. Toxicity The toxicity of organomercury compounds presents both dangers and benefits. Dimethylmercury in particular is notoriously toxic, but found use as an antifungal a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiomersal
Thiomersal (International Nonproprietary Name, INN), or thimerosal (United States Adopted Name, USAN, Japanese Accepted Name, JAN), also sold under the name merthiolate, is an organomercury compound. It is a well-established antiseptic and antifungal agent. The pharmaceutical corporation Eli Lilly and Company named it Merthiolate. It has been used as a preservative in vaccines, immunoglobulin preparations, Allergy#Diagnosis, skin test antigens, antivenins, ophthalmology, 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 Thiomersal controversy, called into question by vaccine hesitancy, anti-vaccination groups. A 1999 statement issued in Centers for Disease Control and Prevention, CDC's Morbidity and Mortality Weekly Report announced that "the Public Health Service (United States Public Health Service Commissioned Corps, PHS), the American Academy of Ped ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thimerosal
Thiomersal ( INN), or thimerosal ( USAN, JAN), also sold under the name merthiolate, is an organomercury compound. It is a well-established antiseptic and antifungal agent. The pharmaceutical corporation Eli Lilly and Company named it 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. A 1999 statement issued in CDC's Morbidity and Mortality Weekly Report announced that "the Public Health Service ( PHS), the American Academy of Pediatrics ( AAP), and vaccine manufacturers agree that thimerosal-containing vaccines should be removed as soon as possible" and that these groups would collaborate to replace them while manufacturers committed "to eliminate or reduce as expeditiously as ... [...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, Denmark, 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, Merbromin is useful on infections of the fingernail or toenail. In 1998, the U.S. Food and Drug Administration recl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organometallic Compounds
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury(II) Acetate
Mercury(II) acetate, also known as mercuric acetate is a chemical compound, the mercury(II) salt of acetic acid, with the formula Hg( O2 CC H3)2. Commonly abbreviated Hg(OAc)2, this compound is employed as a reagent to generate organomercury compounds from unsaturated organic precursors. It is a white, water-soluble solid, but some samples can appear yellowish with time owing to decomposition. Structure Mercury(II) acetate is a crystalline solid consisting of isolated Hg(OAc)2 molecules with Hg-O distances of 2.07 Å. Three long, weak intermolecular Hg···O bonds of about 2.75 Å are also present, resulting in a slightly distorted square pyramidal coordination geometry at Hg. Synthesis and reactions Mercury(II) acetate can be produced by reaction of mercuric oxide with acetic acid. HgO + 2 CH3COOH → Hg(CH3COO)2 + H2O Inorganic reactions Mercury(II) acetate in acetic acid solution reacts with H2S to rapidly precipitate the black (β) polymorph of HgS. With ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury (element)
Mercury is a chemical element; it has Symbol (chemistry), symbol Hg and atomic number 80. It is commonly known as quicksilver. A Heavy metal element, heavy, silvery d-block 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. Exposure to mercury and mercury-containing organic compounds is toxic to the nervous system, immune system and kidneys of humans and other animals; mercury poisoning can result from exposure to water-soluble forms of mercury (such as mercuric chloride or methylmercury) either directly or through mechanisms of biomagnification. Mercu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C(HgOAc)4
Tetrakis(acetoxymercuri)methane is an organomercury compound with the formula formula . It was obtained in the investigation of Hofmann's base, an ill-defined yellowish material produced by treatment of mercuric oxide with base in ethanol. Hofmann's base was once thought to have the formula . Eventually it was found to dissolve in carboxylic acids (RCO2H) to give colorless derivatives of the type . Several tetramercurimethane derivatives have now been characterized by X-ray crystallography. Independent of studies on Hofmann's base, tetrakis(acetoxymercuri)methane was first prepared by reaction of the tetraborylmethane with mercuric acetate Mercury(II) acetate, also known as mercuric acetate is a chemical compound, the mercury(II) salt of acetic acid, with the formula Hg( O2 CC H3)2. Commonly abbreviated Hg(OAc)2, this compound is employed as a reagent to generate organomercury com ....{{cite journal , doi=10.1021/ja00704a055 , title=Tetrakis(acetoxymercuri)methane , date=197 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimethylmercury
Dimethylmercury is an extremely toxic organomercury compound with the formula ( CH3)2 Hg. A volatile, flammable, dense and colorless liquid, dimethylmercury is one of the strongest known neurotoxins. Less than 0.1 mL is capable of inducing severe mercury poisoning resulting in death. 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, Edward 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 methyllithium: : HgCl2 + 2 LiCH3 → Hg(CH3)2 + 2 LiCl The molecule adopts a linear structure with Hg–C bond lengths of 2.083 Å. Reactivity and physical propert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otto Dimroth
Otto Dimroth (28 March 1872 – 16 May 1940) was a German chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a graduated scientist trained in the study of chemistry, or an officially enrolled student in the field. Chemists study the composition of .... He is known for the Dimroth rearrangement, as well as a type of condenser with an internal double spiral, the Dimroth condenser. He made pioneering contributions to organomercury chemistry. His son Karl Dimroth was also a renowned chemist, who described the first synthesis of 3-benzoxepin. References * Academic staff of the University of Greifswald 1872 births 1940 deaths {{germany-scientist-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arene
Aromatic compounds or arenes are organic compounds "with a chemistry typified by benzene" and "cyclically conjugated." The word "aromatic" originates from the past grouping of molecules based on odor, before their general chemical properties were understood. The current definition of aromatic compounds does not have any relation to their odor. Aromatic compounds are now defined as cyclic compounds satisfying Hückel's rule. Aromatic compounds have the following general properties: * Typically unreactive * Often non polar and hydrophobic * High carbon-hydrogen ratio * Burn with a strong sooty yellow flame, due to high C:H ratio * Undergo electrophilic substitution reactions and nucleophilic aromatic substitutions Arenes are typically split into two categories - benzoids, that contain a benzene derivative and follow the benzene ring model, and non-benzoids that contain other aromatic cyclic derivatives. Aromatic compounds are commonly used in organic synthesis and are involved i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenol
Phenol (also known as carbolic acid, phenolic acid, or benzenol) is an aromatic organic compound with the molecular formula . It is a white crystalline solid that is volatile and can catch fire. The molecule consists of a phenyl group () bonded to a hydroxy group (). Mildly acidic, it requires careful handling because it can cause chemical burns. It is acutely toxic and is considered a health hazard. Phenol was first extracted from coal tar, but today is produced on a large scale (about 7 million tonnes a year) from petroleum-derived feedstocks. It is an important industrial commodity as a precursor to many materials and useful compounds, and is a liquid when manufactured. It is primarily used to synthesize plastics and related materials. Phenol and its chemical derivatives are essential for production of polycarbonates, epoxies, explosives such as picric acid, Bakelite, nylon, detergents, herbicides such as phenoxy herbicides, and numerous pharmaceuti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
