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(Cycloheptatrienyl)(cyclopentadienyl)vanadium
(Cycloheptatrienyl)(cyclopentadienyl)vanadium is an organovanadium compound with the formula V(C5H5)(C7H7). It is a purple, paramagnetic, sublimable solid that is sensitive toward air. The structure has been confirmed by X-ray crystallography. This sandwich complex features cyclopentadienyl and cycloheptatrienyl ligands bound to vanadium. It was first prepared by heating a mixture of cycloheptatriene and cyclopentadienylvanadium tetracarbonyl. Many derivatives of trovacene are prepared by lithiation of the cyclopentadienyl ring. See also *(Cycloheptatrienyl)(cyclopentadienyl)titanium (Cycloheptatrienyl)(cyclopentadienyl)titanium is an organotitanium compound with the formula Ti(C7H7)(C5H5). It is a blue, diamagnetic, sublimable solid that is air-free technique, sensitive toward air. The structure has been confirmed by X-ray c ... References {{DEFAULTSORT:Cycloheptatrienyl)(cyclopentadienyl)vanadium Organovanadium compounds Cyclopentadienyl complexes Cycloheptatrienyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organovanadium Compound
Organovanadium chemistry is the chemistry of organometallic compounds containing a carbon (C) to vanadium (V) chemical bond. Organovanadium compounds find only minor use as reagents in organic synthesis but are significant for polymer chemistry as catalysts. Oxidation states for vanadium are +2, +3, +4 and +5. Low valency vanadium is usually stabilized with carbonyl ligands. Oxo derivatives are relatively common, unlike the organic complexes of neighboring elements. Compound classes Carbonyls Vanadium carbonyl can be prepared by reductive carbonylation of vanadium salts: :4 Na + VCl3 + 6 CO → Na (CO)6+ 3 NaCl The salt can be oxidized to the 17e binary carbonyl V(CO)6. Conversely, reduction gives the V(CO) anion. The rubidium and cesium salts are stable at room temperature, but not the sodium salt. Soft electrophiles attack the anion to give heptacoordinate and octacoordinate cluster complexes. Cyclopentadienyl derivatives 130px, (Cycloheptatrienyl)(cyclopentadienyl)vanad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
(Cycloheptatrienyl)(cyclopentadienyl)titanium
(Cycloheptatrienyl)(cyclopentadienyl)titanium is an organotitanium compound with the formula Ti(C7H7)(C5H5). It is a blue, diamagnetic, sublimable solid that is air-free technique, sensitive toward air. The structure has been confirmed by X-ray crystallography. This sandwich complex features cyclopentadienyl and cycloheptatrienyl ligands bound to titanium. The Ti-C distances are all within a narrow range near 2.35 Å. The complex can be prepared by the reaction of titanocene dichloride, butyllithium, and cycloheptatriene. See also *(Cycloheptatrienyl)(cyclopentadienyl)vanadium References [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organovanadium Compounds
Organovanadium chemistry is the chemistry of organometallic compounds containing a carbon (C) to vanadium (V) chemical bond. Organovanadium compounds find only minor use as reagents in organic synthesis but are significant for polymer chemistry as catalysts. Oxidation states for vanadium are +2, +3, +4 and +5. Low valency vanadium is usually stabilized with carbonyl ligands. Oxo derivatives are relatively common, unlike the organic complexes of neighboring elements. Compound classes Carbonyls Vanadium carbonyl can be prepared by reductive carbonylation of vanadium salts: :4 Na + VCl3 + 6 CO → Na[V(CO)6] + 3 NaCl The salt can be oxidized to the 17e binary carbonyl V(CO)6. Conversely, reduction gives the V(CO) anion. The rubidium and cesium salts are stable at room temperature, but not the sodium salt. Soft electrophiles attack the anion to give heptacoordinate and octacoordinate cluster complexes. Cyclopentadienyl derivatives file:Trovacene.svg, 130px, (Cycloheptatrienyl)(cy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air-free Technique
Air-free techniques refer to a range of manipulations in the chemistry laboratory for the handling of compounds that are air-sensitive. These techniques prevent the compounds from reacting with components of air, usually water and oxygen; less commonly carbon dioxide and nitrogen. A common theme among these techniques is the use of a fine (100–10−3 Torr) or high (10−3–10−6 Torr) vacuum to remove air, and the use of an inert gas: preferably argon, but often nitrogen. The two most common types of air-free technique involve the use of a glovebox and a Schlenk line, although some rigorous applications use a high-vacuum line. In both methods, glassware (often Schlenk tubes) are pre-dried in ovens prior to use. They may be flame-dried to remove adsorbed water. Prior to coming into an inert atmosphere, vessels are further dried by ''purge-and-refill'' — the vessel is subjected to a vacuum to remove gases and water, and then refilled with inert gas. This cycle is usually ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Crystallography
X-ray crystallography is the experimental science of determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to Diffraction, diffract in specific directions. By measuring the angles and intensities of the X-ray diffraction, a crystallography, crystallographer can produce a three-dimensional picture of the density of electrons within the crystal and the positions of the atoms, as well as their chemical bonds, crystallographic disorder, and other information. X-ray crystallography has been fundamental in the development of many scientific fields. In its first decades of use, this method determined the size of atoms, the lengths and types of chemical bonds, and the atomic-scale differences between various materials, especially minerals and alloys. The method has also revealed the structure and function of many biological molecules, including vitamins, drugs, proteins and nucleic acids such as DNA. X-ray crystall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cycloheptatriene
Cycloheptatriene (CHT) is an organic compound with the chemical formula, formula C7H8. It is a closed ring of seven carbon atoms joined by three double bonds (as the name implies) and four single bonds. This colourless liquid has been of recurring theoretical interest in organic chemistry. It is a ligand in organometallic chemistry and a building block in organic synthesis. Cycloheptatriene is not aromatic, as reflected by the nonplanarity of the methylene bridge () with respect to the other atoms; however the related tropylium cation is, rendering the compound relatively suspectible to oxidation. Synthesis Albert Ladenburg first generated cycloheptatriene in 1881 by the decomposition of tropine. The structure was finally proven by the synthesis of Richard Willstätter in 1901. This synthesis started from cycloheptanone and established the seven membered ring structure of the compound. Cycloheptatriene can be obtained in the laboratory by photochemical reaction of benzene with d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclopentadienyl Complexes
Cyclopentadienyl can refer to *Cyclopentadienyl anion Sodium cyclopentadienide is an organosodium compound with the formula C5H5Na. The compound is often abbreviated as NaCp, where Cp− is the cyclopentadienide anion. Sodium cyclopentadienide is a colorless solid, although samples often are pin ..., or cyclopentadienide, ** Cyclopentadienyl ligand * Cyclopentadienyl radical, • * Cyclopentadienyl cation, See also * Pentadienyl {{Chemistry index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cycloheptatrienyl Complexes
The tropylium ion or cycloheptatrienyl cation is an aromatic species with a formula of 7H7sup>+. Its name derives from the molecule tropine from which cycloheptatriene (tropylidene) was first synthesized in 1881. Salts of the tropylium cation can be stable, even with nucleophiles of moderate strength e.g., tropylium tetrafluoroborate and tropylium bromide (''see below''). Its bromide and chloride salts can be made from cycloheptatriene and bromine or phosphorus pentachloride, respectively. It is a regular heptagonal, planar, cyclic ion. It has 6 π-electrons (4''n'' + 2, where ''n'' = 1), which fulfills Hückel's rule of aromaticity. It can coordinate as a ligand to metal atoms. The structure shown is a composite of seven resonance contributors in which each carbon atom carries part of the positive charge. History In 1891 G. Merling obtained a water-soluble bromine-containing compound from the reaction of cycloheptatriene and bromine. Unlike most alkyl b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
