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Cyclopentadienyl
Cyclopentadienyl can refer to * Cyclopentadienyl anion, or cyclopentadienide, ** Cyclopentadienyl ligand * Cyclopentadienyl radical, • * Cyclopentadienyl cation, See also * Pentadienyl {{Chemistry index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclopentadienyl Ligand
A cyclopentadienyl complex is a coordination complex of a metal and cyclopentadienyl groups (, abbreviated as Cp−). Cyclopentadienyl ligands almost invariably bind to metals as a pentahapto (''η''5-) bonding mode. The metal–cyclopentadienyl interaction is typically drawn as a single line from the metal center to the center of the Cp ring.Elschenbroich, C. "Organometallics" (2006) Wiley-VCH: Weinheim. Examples ''Bis''cyclopentadienyl complexes are called metallocenes. A famous example of this type of complex is ferrocene (FeCp2), which has many analogues for other metals, such as chromocene (CrCp2), cobaltocene (CoCp2), and nickelocene (NiCp2). When the Cp rings are mutually parallel the compound is known as a sandwich complex. This area of organometallic chemistry was first developed in the 1950s. Bent metallocenes are represented by compounds of the type Cp2Lx Some are catalysts for ethylene polymerization. Metallocenes are often thermally stable, and find use as c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclopentadienyl Anion
In chemistry, the cyclopentadienyl anion or cyclopentadienide is an aromatic species with a formula of and abbreviated as Cp−. It is formed from the deprotonation of the molecule cyclopentadiene. Properties The cyclopentadienyl anion is a planar, cyclic, regular-pentagonal ion; it has 6 π-electrons (4''n'' + 2, where ''n'' = 1), which fulfills Hückel's rule of aromaticity. The structure shown is a composite of five resonance contributors in which each carbon atom carries part of the negative charge. Salts of the cyclopentadienyl anion can be stable, e.g., sodium cyclopentadienide. It can also coordinate as a ligand to metal atoms, forming coordination compounds known as cyclopentadienyl complexes. Biscyclopentadienyl complexes are called metallocenes. Cyclopentadienyl, , and cyclopentadiene, , can substitute one or more hydrogens, forming derivatives having covalent bonds. (See Cyclopentadiene#Derivatives) Abbreviation The abbreviation Cp for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclopentadienyl Cation
Antiaromaticity is a chemical property of a cyclic molecule with a π electron system that has higher energy, i.e., it is less stable due to the presence of 4n delocalised (π or lone pair) electrons in it, as opposed to aromaticity. Unlike aromatic compounds, which follow Hückel's rule ( ''n''+2π electrons) and are highly stable, antiaromatic compounds are highly unstable and highly reactive. To avoid the instability of antiaromaticity, molecules may change shape, becoming non-planar and therefore breaking some of the π interactions. In contrast to the diamagnetic ring current present in aromatic compounds, antiaromatic compounds have a paramagnetic ring current, which can be observed by NMR spectroscopy. Examples of antiaromatic compounds are pentalene (A), biphenylene (B), cyclopentadienyl cation (C). The prototypical example of antiaromaticity, cyclobutadiene, is the subject of debate, with some scientists arguing that antiaromaticity is not a major factor contributing t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclopentadienyl Radical
In chemistry, cyclopentadienyl is a radical with the formula C5 H5. The cyclopentadienyl anion (formally related to the cyclopentadienyl radical by one-electron reduction) is aromatic, and forms salts and coordination compounds. See also *Cyclopentadienyl anion, 5H5sup>− *Cyclopentadienyl cation, 5H5sup>+ *Cyclopentadiene, C5H6 *Methyl radical Methyl (also systematically named trihydridocarbon) is an organic compound with the chemical formula (also written as •). It is a metastable colourless gas, which is mainly produced ''in situ'' as a precursor to other hydrocarbons in the petrol ..., H3sup>• References {{organic-chem-stub Free radicals Five-membered rings ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
