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Pentamethylcyclopentadienyl Rhodium Dichloride Dimer
Pentamethylcyclopentadienyl rhodium dichloride dimer is an organometallic compound with the formula C5(CH3)5RhCl2)sub>2, commonly abbreviated p*RhCl2sub>2 This dark red air-stable diamagnetic solid is a reagent in organometallic chemistry. Structure and preparation The compound has idealized C2h symmetry. Each metal centre is pseudooctahedral. The compound is prepared by the reaction of rhodium trichloride trihydrate and pentamethylcyclopentadiene in hot methanol, from which the product precipitates: : It was first prepared by the reaction of hydrated rhodium trichloride with hexamethyl Dewar benzene This complex was first prepared from hexamethyl Dewar benzene and RhCl3(H2O)3. The hydrohalic acid necessary for the ring-contraction rearrangement is generated ''in situ'' in methanolic solutions of the rhodium salt, and the second step has been carried out separately, confirming this mechanistic description. The reaction occurs with the formation of 1,1-dimethoxyethane, ... [...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 carbonyl, 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 "metalorganics, metalorganic compound" refers to metal-containing compounds lacking direct metal-carbon bonds but which contain organic ligands. Metal β-diketonates, alkoxides, dialkylamides, and metal p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georg Thieme Verlag
Thieme Medical Publishers is a German medical and science publisher in the Thieme Publishing Group. It produces professional journals, textbooks, atlases, monographs and reference books in both German and English covering a variety of medical specialties, including neurosurgery, orthopaedics, endocrinology, urology, radiology, anatomy, chemistry, otolaryngology, ophthalmology, audiology and speech-language pathology, complementary and alternative medicine. Thieme has more than 1,000 employees and maintains offices in seven cities worldwide, including New York City, Beijing, Delhi, Stuttgart, and three other cities in Germany. History Georg Thieme Verlag was founded in 1886 in Leipzig, Germany, by Georg Thieme when he was 26 years old. Thieme remains privately held and family-owned. The company received some early success in 1896 by publishing Wilhelm Röntgen's famous picture of his wife's hand in what is still one of Thieme's and Germany's oldest journals, the ''Deutsche ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentamethylcyclopentadienyl Complexes
1,2,3,4,5-Pentamethylcyclopentadiene is a cyclic diene with the formula , often written , where Me is . It is a colorless liquid. 1,2,3,4,5-Pentamethylcyclopentadiene is the precursor to the ligand ''1,2,3,4,5-pentamethylcyclopentadienyl'', which is often denoted Cp* () and read as "C P star", the "star" signifying the five methyl groups radiating from the core of the ligand. Thus, the 1,2,3,4,5-pentamethylcyclopentadiene's formula is also written Cp*H. In contrast to less-substituted cyclopentadiene derivatives, Cp*H is not prone to dimerization. Synthesis Pentamethylcyclopentadiene is commercially available. It was first prepared from tiglaldehyde and 2-butenyllithium, via 2,3,4,5-tetramethylcyclopent-2-enone, with a Nazarov cyclization reaction as a key step. : Alternatively, 2-butenyllithium adds to ethyl acetate followed by acid-catalyzed dehydrocyclization: : : Organometallic derivatives Cp*H is a precursor to organometallic compounds containing the ligand, common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimers (chemistry)
Dimers is a sports betting analytics platform that provides predictive tools, data-driven insights, news, and betting content for sports fans and bettors. Operating under the umbrella of Cipher Sports Technology Group, Dimers has offices in Melbourne and New York. History Dimers.com was launched on August 1, 2020, shortly after its parent company Cipher Sports Technology Group was formed through the merger of two Australian companies: iRival Media and Hypometer Technologies. iRival Media, founded in October 2019 by Adam Fiske and Nick Slade, focused on delivering content to the sports betting market.Hypometer Technologies, established in 2015 by Katie Prowd and Darryl Woodford, specialized in predictive analytics and machine learning for sports. Dimers’ data has been cited by publications such as ''Sports Illustrated,'' ''USA Today,'' and ''The Arizona Republic ''The Arizona Republic'' is an American daily newspaper published in Phoenix. Circulated throughout Arizo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organorhodium Compounds
Organorhodium chemistry is the chemistry of organometallic compounds containing a rhodium-carbon chemical bond, and the study of rhodium and rhodium compounds as catalysts in organic reactions. Stable organorhodium compounds and transient organorhodium intermediates are used as catalyst such as in olefin hydroformylation, olefin hydrogenation, olefin isomerization and the Monsanto process. Classification based on principal oxidation states Organometallic rhodium compounds share many characteristics with those of iridium, but less so with cobalt. Rhodium can exist in oxidation states of −3 to +5, but rhodium(I) and rhodium(III) are the more common. Rhodium(I) compounds (d8 configuration) usually occur with square planar or trigonal bipyramidal geometries, while rhodium (III) compounds (d6 configuration) typically have an octahedral geometry. Rhodium(0) Rhodium(0) complexes are binary carbonyls, the principal examples being tetrarhodium dodecacarbonyl, Rh4(CO)12, and hexadecacarbo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chem , a place in Finland
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Chem may refer to: *Chemistry *Chemical * ''Chem'' (journal), a scientific journal published by Cell Press *Post apocalyptic slang for "drugs", medicinal or otherwise in the Fallout video game series. In Ancient Egyptian usage: * ''Khem'' (also spelt ''Chem''), the Egyptian word for "black" *Min (god), in the past erroneously named ''Khem'' CHEM may refer to : *A metabolic panel: for instance, CHEM-7, which is the basic metabolic panel * CHEM-DT, a Canadian television channel See also * Chemo (other) * Kem (other) *Kemi Kemi (; ; ; ) is a cities of Finland, town and municipalities of Finland, municipality of Finland. It is located approximately from the city of Tornio and the Finland–Sweden border, Swedish border. The distance to Oulu is to the south and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentamethylcyclopentadienyl Iridium Dichloride Dimer
Pentamethylcyclopentadienyl iridium dichloride dimer is an organometallic compound with the formula C5(CH3)5IrCl2)sub>2, commonly abbreviated p*IrCl2sub>2 This bright orange air-stable diamagnetic solid is a reagent in organometallic chemistry. Structure The compound has C2h symmetry. Each metal is pseudo-octahedral. The terminal and bridging Ir-Cl bonds have the lengths 2.39 and 2.45 Å, respectively. Preparation, reactions Pentamethylcyclopentadienyl iridium dichloride dimer was first prepared by the reaction of hydrated iridium trichloride with hexamethyl Dewar benzene. More conveniently, the compound is prepared by the reaction of hydrated iridium trichloride and pentamethylcyclopentadiene in hot methanol, from which the product precipitates :2 Cp*H + 2 IrCl3(H2O)3 → p*IrCl2sub>2 + 2 HCl + 6 H2O The Ir-'' μ''-Cl bonds are labile and can be cleaved to give a variety of adducts of the general formula Cp*IrCl2L. Such adducts undergo further substitution to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analog (chemistry)
A structural analog, also known as a chemical analog or simply an analog, is a compound having a structure similar to that of another compound, but differing from it in respect to a certain component. It can differ in one or more atoms, functional groups, or substructures, which are replaced with other atoms, groups, or substructures. A structural analog can be imagined to be formed, at least theoretically, from the other compound. Structural analogs are often isoelectronic. Despite a high chemical similarity, structural analogs are not necessarily functional analogs and can have very different physical, chemical, biochemical, or pharmacological properties. In drug discovery, either a large series of structural analogs of an initial lead compound are created and tested as part of a structure–activity relationship study or a database is screened for structural analogs of a lead compound. Chemical analogues of illegal drugs are developed and sold in order to circumvent la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver(I) Chloride
Silver chloride is an inorganic chemical compound with the chemical formula Silver, AgChlorine, Cl. This white crystalline solid is well known for its low solubility in water and its Photosensitivity, sensitivity to light. Upon illumination or heating, silver chloride converts to silver (and chlorine), which is signaled by grey to black or purplish coloration in some samples. AgCl occurs naturally as the mineral chlorargyrite. It is produced by a salt metathesis reaction, metathesis reaction for use in photography and in pH meters as silver chloride electrode, electrodes. Preparation Silver chloride is unusual in that, unlike most chloride salts, it has very low solubility. It is easily synthesized by Salt metathesis reaction, metathesis: combining an aqueous solution of silver nitrate (which is soluble) with a soluble chloride salt, such as sodium chloride (which is used industrially as a method of producing AgCl), or cobalt(II) chloride. The silver chloride that forms will pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bridging Ligand
In coordination chemistry, a bridging ligand is a ligand that connects two or more atoms, usually metal ions. The ligand may be atomic or polyatomic. Virtually all complex organic compounds can serve as bridging ligands, so the term is usually restricted to small ligands such as pseudohalides or to ligands that are specifically designed to link two metals. In naming a complex wherein a single atom bridges two metals, the bridging ligand is preceded by the Greek letter mu, μ, with a subscript number denoting the number of metals bound to the bridging ligand. μ2 is often denoted simply as μ. When describing coordination complexes care should be taken not to confuse μ with η ('eta'), which relates to hapticity. Ligands that are not bridging are called terminal ligands. List of bridging ligands Virtually all ligands are known to bridge, with the exception of amines and ammonia. Common bridging ligands include most of the common anions. Many simple organic ligands form s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonylation
In chemistry, carbonylation refers to reactions that introduce carbon monoxide (CO) into organic and inorganic substrates. Carbon monoxide is abundantly available and conveniently reactive, so it is widely used as a reactant in industrial chemistry. The term carbonylation also refers to oxidation of protein side chains. Organic chemistry Several industrially useful organic chemicals are prepared by carbonylations, which can be highly selective reactions. Carbonylations produce organic carbonyls, i.e., compounds that contain the functional group such as aldehydes (), carboxylic acids () and esters (). Carbonylations are the basis of many types of reactions, including hydroformylation and Reppe reactions. These reactions require metal catalysts, which bind and activate the CO. These processes involve transition metal acyl complexes as intermediates. Much of this theme was developed by Walter Reppe. Hydroformylation Hydroformylation entails the addition of both carbon monoxide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc
Zinc is a chemical element; it has symbol Zn and atomic number 30. It is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic table. In some respects, zinc is chemically similar to magnesium: both elements exhibit only one normal oxidation state (+2), and the Zn2+ and Mg2+ ions are of similar size. Zinc is the 24th most abundant element in Earth's crust and has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest workable lodes are in Australia, Asia, and the United States. Zinc is refined by froth flotation of the ore, roasting, and final extraction using electricity ( electrowinning). Zinc is an essential trace element for humans, animals, plants and for microorganisms and is necessary for prenatal and postnatal development. It is the second most abundant trace metal in humans after iron, an import ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
