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Fulvene
Fulvene (pentafulvene) is a hydrocarbon with the formula (CH=CH)2C=CH2. It is a prototype of a cross-conjugated hydrocarbon. Fulvene is rarely encountered, but substituted derivatives ( fulvenes) are numerous. They are mainly of interest as ligands and precursors to ligands in organometallic chemistry. See also *Fulvalene Fulvalene (bicyclopentadienylidene) is the member of the fulvalene family with the molecular formula C10H8. It is of theoretical interest as one of the simplest non-benzenoid conjugated hydrocarbons. Fulvalene is an unstable isomer of the mor ... * Methylenecyclopropene References {{Authority control Hydrocarbons Vinylidene compounds Cyclopentadienes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fulvenes
Fulvenes are the class of hydrocarbon obtained by formally cross-conjugating one ring and methylidene through a common exocyclic double bond. The name is derived from fulvene, which has one pentagonal ring. Other examples include methylenecyclopropene (triafulvene) and heptafulvene. Subclasses Several types of fulvenes are defined. They are: *pentafulvene * triafulvene *heptafulvene *nonafulvene Preparation Fulvenes are readily prepared by the condensation of cyclopentadiene and aldehydes and ketones: :C5H6 + R2C=O → C4H4C=CR2 + H2O Thiele is credited with discovering this reaction. Modern synthesis of fulvenes employ buffer systems. Ligand in organometallic chemistry Fulvenes are common ligands and ligand precursors in organometallic chemistry. 2,3,4,5-Tetramethylfulvene, abbreviated Me4Fv, results from the deprotonation of cationic pentamethylcyclopentadienyl complexes. Some Me4Fv complexes are called tuck-in complex In organometallic chemistry, a tuck-in complex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fulvalene
Fulvalene (bicyclopentadienylidene) is the member of the fulvalene family with the molecular formula C10H8. It is of theoretical interest as one of the simplest non-benzenoid conjugated hydrocarbons. Fulvalene is an unstable isomer of the more common benzenoid aromatic compounds naphthalene and azulene. Fulvalene consists of two 5-membered rings, each with two double bonds, joined by yet a fifth double bond. It has D2h symmetry. History An earlier attempt at synthesis of fulvalene in 1951 by Pauson and Kealy resulted in the accidental discovery of ferrocene. Its synthesis was first reported in 1958 by E. A. Matzner, working under William von Eggers Doering. In this method, cyclopentadienyl anion is coupled with iodine to the dihydrofulvalene. Double deprotonation of dihydrofulvalene with ''n''-butyllithium gives the dilithio derivative, which oxidizes with oxygen. Fulvalene was spectroscopically observed at from photolysis of diazocyclopentadiene, which induces dimer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylenecyclopropene
3-Methylenecyclopropene, also called methylenecyclopropene or triafulvene, is a hydrocarbon with chemical formula . It is a colourless gas that polymerizes readily as a liquid or in solution but is stable as a gas.W. E. Billups , Long Jin Lin , Edward W. Casserly "Synthesis of Methylenecyclopropene" J. Am. Chem. Soc., 1984, volume 106, pp 3698–3699. This highly strained and reactive molecule was synthesized and characterized for the first time in 1984, and has been the subject of considerable experimental and theoretical interest. It is an example of a cross-conjugated alkene, being composed of cyclopropene with an exocyclic double bond attached. Description Methylenecyclopropene is the smallest of the fulvenes (a family of unstable, cyclic molecules, conjugated transversally with an odd number of carbon atoms in the ring). The structure of methylenecyclopropene has two interacting double bonds, which represents the simplest transversally conjugated π-bonding system. It i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Society Of Chemistry
The Royal Society of Chemistry (RSC) is a learned society (professional association) in the United Kingdom with the goal of "advancing the chemistry, chemical sciences". It was formed in 1980 from the amalgamation of the Chemical Society, the Royal Institute of Chemistry, the Faraday Society, and the Society for Analytical Chemistry with a new Royal Charter and the dual role of learned society and professional body. At its inception, the Society had a combined membership of 34,000 in the UK and a further 8,000 abroad. The headquarters of the Society are at Burlington House, Piccadilly, London. It also has offices in Thomas Graham House in Cambridge (named after Thomas Graham (chemist), Thomas Graham, the first president of the Chemical Society) where ''RSC Publishing'' is based. The Society has offices in the United States, on the campuses of The University of Pennsylvania and Drexel University, at the University City Science Center in Philadelphia, Pennsylvania, in both Beijing a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Reviews
''Chemical Reviews'' is peer-reviewed scientific journal published twice per month by the American Chemical Society. It publishes review articles on all aspects of chemistry. It was established in 1924 by William Albert Noyes (University of Illinois). the editor-in-chief is Sharon Hammes-Schiffer. Abstracting and indexing The journal is abstracted and indexed in Chemical Abstracts Service, CAB International, EBSCOhost, ProQuest, PubMed, Scopus, and the Science Citation Index. According to the ''Journal Citation Reports'', the journal has a 2020 impact factor of 60.622. See also * Accounts of Chemical Research ''Accounts of Chemical Research'' is a semi-monthly peer-reviewed scientific journal published by the American Chemical Society containing overviews of basic research and applications in chemistry and biochemistry. It was established in 1968 and th ... References External links * American Chemical Society academic journals Review journals Monthly journals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ligand
In coordination chemistry, a ligand is an ion or molecule (functional group) that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's electron pairs, often through Lewis bases. The nature of metal–ligand bonding can range from covalent to ionic. Furthermore, the metal–ligand bond order can range from one to three. Ligands are viewed as Lewis bases, although rare cases are known to involve Lewis acidic "ligands". Metals and metalloids are bound to ligands in almost all circumstances, although gaseous "naked" metal ions can be generated in a high vacuum. Ligands in a complex dictate the reactivity of the central atom, including ligand substitution rates, the reactivity of the ligands themselves, and redox. Ligand selection requires critical consideration in many practical areas, including bioinorganic and medicinal chemistry, homogeneous catalysis, and environmental chemi ... [...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 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 are repres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrocarbons
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or exemplified by the odors of gasoline and lighter fluid. They occur in a diverse range of molecular structures and phases: they can be gases (such as methane and propane), liquids (such as hexane and benzene), low melting solids (such as paraffin wax and naphthalene) or polymers (such as polyethylene and polystyrene). In the fossil fuel industries, ''hydrocarbon'' refers to the naturally occurring petroleum, natural gas and coal, and to their hydrocarbon derivatives and purified forms. Combustion of hydrocarbons is the main source of the world's energy. Petroleum is the dominant raw-material source for organic commodity chemicals such as solvents and polymers. Most anthropogenic (human-generated) emissions of greenhouse gases are carb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vinylidene Compounds
Methylidenecarbene (systematically named λ2-ethene and dihydrido-1κ2''H''-dicarbon(''C''—''C'')) is an organic compound with the chemical formula (also written [] or ). It is a metastability, metastable proton tautomer of acetylene, which only persists as an adduct. It is a colourless gas that phosphoresces in the far-infrared range. It is the simplest unsaturated carbene. Nomenclature The systematic names ''λ2-ethene'', and ''dihydrido-1κ2H-dicarbon(C—C)'', valid IUPAC names, are constructed according to the substitutive and additive nomenclatures, respectively. In appropriate contexts, methylidenecarbene can be viewed as ethene with two hydrogen atoms removed, or as ethane with four hydrogens removed; and as such, ''ethen-1-ylidene'' (or ''vinylidene'') or ''ethane-1-diylidene'', respectively, may be used as a context-specific systematic names, according to substitutive nomenclature. By default, these names pay no regard to the radicality of the methylidenecarbene m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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