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Ferrole
In organoiron chemistry, a ferrole is a type of diiron complex containing the (OC)3FeC4R4 heterocycle that is pi-bonded to a Fe(CO)3 group. These compounds have Fe-Fe bonds (ca. 252 pm) and semi-bridging CO ligands (Fe-C distances = 178, 251 pm). They are typically air-stable, soluble in nonpolar solvents, and red-orange in color. Synthesis Ferroles typically arise by the reaction of alkynes with iron carbonyls. Such reactions are known to generate many products, e.g. complexes of cyclopentadienones and para-quinone The quinones are a class of organic compounds that are formally "derived from aromatic compounds benzene.html" ;"title="uch as benzene">uch as benzene or naphthalene] by conversion of an even number of –CH= groups into –C(=O)– groups with ...s. Another route involves the desulfurization of thiophenes (SC4R4) by iron carbonyls, shown in the following idealized equation: :Fe3(CO)12 + SC4R4 → Fe2(CO)6C4R4 + FeS + 6CO An unusual route to ferrole ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organoiron Chemistry
Organoiron chemistry is the chemistry of iron compounds containing a carbon-to-iron chemical bond. Organoiron compounds are relevant in organic synthesis as reagents such as iron pentacarbonyl, diiron nonacarbonyl and disodium tetracarbonylferrate. Although iron is generally less active in many catalytic applications, it is less expensive and " greener" than other metals. Organoiron compounds feature a wide range of ligands that support the Fe-C bond; as with other organometals, these supporting ligands prominently include phosphines, carbon monoxide, and cyclopentadienyl, but hard ligands such as amines are employed as well. Iron(–II) and Iron(0) Carbonyl complexes Important iron carbonyls are the three neutral binary carbonyls, iron pentacarbonyl, diiron nonacarbonyl, and triiron dodecacarbonyl. One or more carbonyl ligands in these compounds can be replaced by a variety of other ligands including alkenes and phosphines. An iron(–II) complex, disodium tetracarbonylfe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flyover Complex
In organometallic chemistry, a flyover complex features two metals bridged by the fragment OC(RC=CR)2. Some flyover complexes are symmetrical and some are not. Common examples are the iron carbonyl derivatives, which are typically air-stable, soluble in nonpolar solvents, and red-orange in color. These diiron complexes arise by the reaction of alkynes with iron carbonyls. Such reactions are known to generate many products, e.g. complexes of cyclopentadienones and para-quinones. Some ferrole complexes react with tertiary phosphines to give the substituted flyover complex Fe2(CO)5(PR3)(C4R4CO). They insert alkynes en route to tropones (R6C7O). {{cite book , doi=10.1016/B978-008046519-7.00058-7, chapter=Dinuclear Iron Compounds with Hydrocarbon Ligands, title=Comprehensive Organometallic Chemistry II, year=1995, last1=Fagan, first1=Paul J., pages=231–258, isbn=9780080465197 References [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organoiron Compounds
Organoiron chemistry is the chemistry of iron compounds containing a carbon-to-iron chemical bond. Organoiron compounds are relevant in organic synthesis as reagents such as iron pentacarbonyl, diiron nonacarbonyl and disodium tetracarbonylferrate. Although iron is generally less active in many catalytic applications, it is less expensive and "Green chemistry, greener" than other metals. Organoiron compounds feature a wide range of ligands that support the Fe-C bond; as with other organometals, these supporting ligands prominently include phosphines, carbon monoxide, and cyclopentadienyl, but HSAB theory, hard ligands such as amines are employed as well. Iron(–II) and Iron(0) Carbonyl complexes Important metal carbonyls, iron carbonyls are the three neutral binary carbonyls, iron pentacarbonyl, diiron nonacarbonyl, and triiron dodecacarbonyl. One or more carbonyl ligands in these compounds can be replaced by a variety of other ligands including alkenes and phosphines. An iron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Picometer
The picometre (international spelling as used by the International Bureau of Weights and Measures; SI symbol: pm) or picometer ( American spelling) is a unit of length in the International System of Units (SI), equal to , or one trillionth of a metre, which is the SI base unit of length. The picometre is one thousand femtometres, one thousandth of a nanometre ( nm), one millionth of a micrometre (also known as a micron), one billionth of a millimetre, and one trillionth of a metre. The symbol μμ was once used for it. It is also one hundredth of an ångström, an internationally known (but non-SI) unit of length. Use The picometre's length is of an order so small that its application is almost entirely confined to particle physics, quantum physics, chemistry, and acoustics. Atoms are between 62 and 520 pm in diameter, and the typical length of a carbon–carbon single bond is 154 pm. Smaller units still may be used to describe smaller particles (some of which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkyne
\ce \ce Acetylene \ce \ce \ce Propyne \ce \ce \ce \ce 1-Butyne In organic chemistry, an alkyne is an unsaturated hydrocarbon containing at least one carbon—carbon triple bond. The simplest acyclic alkynes with only one triple bond and no other functional groups form a homologous series with the general chemical formula . Alkynes are traditionally known as acetylenes, although the name ''acetylene'' also refers specifically to , known formally as ethyne using IUPAC nomenclature. Like other hydrocarbons, alkynes are generally hydrophobic. Structure and bonding In acetylene, the H–C≡C bond angles are 180°. By virtue of this bond angle, alkynes are rod-like. Correspondingly, cyclic alkynes are rare. Benzyne cannot be isolated. The C≡C bond distance of 118 picometers (for C2H2) is much shorter than the C=C distance in alkenes (132 pm, for C2H4) or the C–C bond in alkanes (153 pm). : The triple bond is very strong with a bond strength of 839 kJ/mol. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron Carbonyl
There are three homoleptic iron carbonyl compounds: * The monomeric iron pentacarbonyl Iron pentacarbonyl, also known as iron carbonyl, is the compound with formula . Under standard conditions Fe( CO)5 is a free-flowing, straw-colored liquid with a pungent odour. Older samples appear darker. This compound is a common precursor t ... * The dimeric diiron nonacarbonyl * The trimeric triiron dodecacarbonyl {{Short pages monitor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclopentadienone
Cyclopentadienone is an organic compound with molecular formula C5H4O. The parent cyclopentadienone is rarely encountered, because it rapidly dimerizes. Many substituted derivatives are known, notably tetraphenylcyclopentadienone. Such compounds are used as ligands in 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 so .... left, The Knölker complex, derived from a substituted cyclopentadienone, is a catalyst for transfer hydrogenation. Preparation Cyclopentadienone can be generated by the photolysis or pyrolysis of various substances (e.g. 1,2-benzoquinone), and then isolated in an matrix isolation, argon matrix at . It dimerizes readily upon thawing the matrix at . See also * Dienone References {{Cyclopentadienide complexes Ketones Fully conjugat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quinone
The quinones are a class of organic compounds that are formally "derived from aromatic compounds benzene.html" ;"title="uch as benzene">uch as benzene or naphthalene] by conversion of an even number of –CH= groups into –C(=O)– groups with any necessary rearrangement of double bonds", resulting in "a fully Conjugated system, conjugated cyclic diketone, dione structure". The archetypical member of the class is 1,4-benzoquinone or cyclohexadienedione, often called simply "quinone" (thus the name of the class). Other important examples are 1,2-benzoquinone (''ortho''-quinone), 1,4-naphthoquinone and 9,10-anthraquinone. The name is derived from that of quinic acid (with the suffix "-one" indicating a ketone), since it is one of the compounds obtained upon oxidation of quinic acid. Quinic acid, like quinine is obtained from cinchona bark, called quinaquina in the indigenous languages of Peruvian tribes. Properties Quinones are oxidized derivatives of aromatic compounds an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collman's Reagent
Disodium tetracarbonylferrate is the organoiron compound with the formula Na2 e(CO)4 It is always used as a solvate, e.g., with tetrahydrofuran or dimethoxyethane, which bind to the sodium cation. An oxygen-sensitive colourless solid, it is a reagent in organometallic and organic chemical research. The dioxane solvated sodium salt is known as Collman's reagent, in recognition of James P. Collman, an early popularizer of its use. Structure The dianion e(CO)4sup>2− is isoelectronic with Ni(CO)4. The iron center is tetrahedral, with Na+---OCFe interactions. It is commonly used with dioxane complexed to the sodium cation. Synthesis The reagent was originally generated in situ by reducing iron pentacarbonyl with sodium amalgam. Modern synthesis use sodium naphthalene or sodium benzophenone ketyls as the reducants: :Fe(CO)5 + 2 Na → Na2 e(CO)4 + CO When a deficiency of sodium is used, the reduction affords deep yellow octacarbonyl ''di''ferrate: :2 Fe(CO)5 + 2 Na → Na2 e2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonyl Complexes
In organic chemistry, a carbonyl group is a functional group with the formula , composed of a carbon atom double-bonded to an oxygen atom, and it is divalent at the C atom. It is common to several classes of organic compounds (such as aldehydes, ketones and carboxylic acid), as part of many larger functional groups. A compound containing a carbonyl group is often referred to as a carbonyl compound. The term carbonyl can also refer to carbon monoxide as a ligand in an inorganic or organometallic complex (a metal carbonyl, e.g. nickel carbonyl). The remainder of this article concerns itself with the organic chemistry definition of carbonyl, such that carbon and oxygen share a double bond. Carbonyl compounds In organic chemistry, a carbonyl group characterizes the following types of compounds: Other organic carbonyls are urea and the carbamates, the derivatives of acyl chlorides, chloroformates and phosgene, carbonate esters, thioesters, lactones, lactams, hydroxamates, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
