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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 Cycloheptatriene (CHT) is an organic compound with the 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 inter ... and cyclopentadienyl)vanadium tetracarbonyl. Many derivatives of trovacene are prepared by lithiation of the cyclopentadienyl ring. See also * (Cycloheptatrienyl)(cyclopentadienyl)titanium References {{DEFAULTSORT:Cycloheptatrienyl)(cyclopentadienyl)vanadium Organovanadium compounds Cyclopentadienyl complexes Cycloheptatrieny ... [...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. Cyclopentadienyl derivatives 130px, (Cycloheptatrienyl)(cyclopentadienyl)vanadium is one of many organovanadium compounds that is paramagnetic. Vanadocene dichloride, the first organovanadium complexes to be reported, is prepared from sodium cyclopentadienyl and vanadium tetrachloride: :2 NaC5H5 + VCl4 → VCp2Cl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclopentadienylvanadium Tetracarbonyl
Cyclopentadienylvanadium tetracarbonyl is the organovanadium compound with the formula (C5H5)V(CO)4. An orange, diamagnetic solid, it is the principal cyclopentadienyl carbonyl of vanadium. It can be prepared by heating a solution of vanadocene under high pressure of carbon monoxide. As confirmed by X-ray crystallography, the coordination sphere of vanadium consists of η5-cyclopentadienyl and four carbonyl ligands. The molecule is a four-legged piano stool complex. The compound is soluble in common organic solvents. The compound has no commercial applications. Reactions Reduction with sodium amalgam gives the dianion of the tricarbonyl: :CpV(CO)4 + 2 Na → Na2CpV(CO)3 + CO Protonation of this salt gives Cp2V2(CO)5. Heating a mixture of cycloheptatriene Cycloheptatriene (CHT) is an organic compound with the 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 bee ... [...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 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 (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. T ... References {{DEFAULTSORT:Cycloheptatrienyl)(cyclopentadienyl)titanium Titanium(II) compounds Cyclopentadienyl complexes Cycloheptatrienyl complexes Sandwich compounds ... [...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 (CO)6+ 3 NaCl The salt can be oxidized to the 17e binary carbonyl V(CO)6. Cyclopentadienyl derivatives 130px, (Cycloheptatrienyl)(cyclopentadienyl)vanadium is one of many organovanadium compounds that is paramagnetic. Vanadocene dichloride, the first organovanadium complexes to be reported, is prepared from sodium cyclopentadienyl and vanadium tetrachloride: :2 NaC5H5 + VCl4 → VCp2Cl ... [...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 r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Crystallography
X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles and intensities of these diffracted beams, a crystallographer can produce a three-dimensional picture of the density of electrons within the crystal. From this electron density, the mean positions of the atoms in the crystal can be determined, as well as their chemical bonds, their crystallographic disorder, and various other information. Since many materials can form crystals—such as salts, metals, minerals, semiconductors, as well as various inorganic, organic, and biological molecules—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 among various mat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cycloheptatriene
Cycloheptatriene (CHT) is an organic compound with the 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 (-CH2-) with respect to the other atoms; however the related tropylium cation is. 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 diazomethane or the pyrolysis of the adduct of cyclohexene and dichlorocar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclopentadienyl Complexes
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Cyclopentadienyl can refer to *Cyclopentadienyl anion, or cyclopentadienide, **Cyclopentadienyl ligand *Cyclopentadienyl radical, • *Cyclopentadienyl cation, See also *Pentadienyl In organic chemistry, pentadienyl refers to the organic radical, anion, or cation with the formula , where ''z'' = 0, −1, +1, respectively. Organometallic chemistry In organometallic chemistry, the pentadienyl anion is a ligand, the acyclic ana ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cycloheptatrienyl Complexes
In organic chemistry, 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. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
