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Cyclobutadieneiron Tricarbonyl
Cyclobutadieneiron tricarbonyl is an organoiron compound with the formula Fe(C4H4)(CO)3. It is a yellow oil that is soluble in organic solvents. It has been used in organic chemistry as a precursor for cyclobutadiene, which is an elusive species in the free state. Preparation and structure Cyclobutadieneiron tricarbonyl was first prepared in 1965 by Pettit from 3,4-dichlorocyclobutene and diiron nonacarbonyl: :C4H4Cl2 + 2 Fe2(CO)9 → (C4H4)Fe(CO)3 + 2 Fe(CO)5 + 5 CO + FeCl2 The compound is an example of a piano stool complex. The C-C distances are 1.426 Å. Properties Oxidative decomplexation of cyclobutadiene is achieved by treating the tricarbonyl complex with ceric ammonium nitrate. The released cyclobutadiene is trapped with a quinone, which functions as a dienophile. Cyclobutadieneiron tricarbonyl displays aromaticity as evidenced by some of its reactions, which can be classified as electrophilic aromatic substitution: : It undergoes Friedel-Crafts acylation with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organoiron Compound
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] |
Formaldehyde
Formaldehyde ( , ) (systematic name methanal) is an organic compound with the chemical formula and structure , more precisely . The compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde. It is stored as aqueous solutions (formalin), which consists mainly of the hydrate CH2(OH)2. It is the simplest of the aldehydes (). As a precursor to many other materials and chemical compounds, in 2006 the global production of formaldehyde was estimated at 12 million tons per year. It is mainly used in the production of industrial resins, e.g., for particle board and coatings. Formaldehyde also occurs naturally. It is derived from the degradation of serine, dimethylglycine, and lipids. Demethylases act by converting N-methyl groups to formaldehyde. Formaldehyde is classified as a group 1 carcinogen and can cause respiratory and skin irritation upon exposure. Forms Formaldehyde is more complicated than many simple carbon compounds in that i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Half Sandwich Compounds
One half is the multiplicative inverse of 2. It is an irreducible fraction with a numerator of 1 and a denominator of 2. It often appears in mathematical equations, recipes and measurements. As a word One half is one of the few fractions which are commonly expressed in natural languages by suppletion rather than regular derivation. In English, for example, compare the compound "one half" with other regular formations like "one-sixth". A ''half'' can also be said to be one part of something divided into two equal parts. It is acceptable to write one half as a hyphenated word, ''one-half''. Mathematics One half is the rational number that lies midway between 0 and 1 on the number line. Multiplication by one half is equivalent to division by two, or "halving"; conversely, division by one half is equivalent to multiplication by two, or "doubling". A number raised to the power of one half is equal to its square root. The area of a triangle is one half its base and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron Carbonyl Complexes
Iron is a chemical element; it has chemical symbol, symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 element, group 8 of the periodic table. It is, by mass, the abundance of the chemical elements#Earth, most common element on Earth, forming much of Earth's outer core, outer and inner core. It is the fourth most abundance of elements in Earth's crust, abundant element in the Earth's crust, being mainly deposited by meteorites in its metallic state. Extracting usable metal from iron ores requires kilns or Metallurgical furnace, furnaces capable of reaching , about 500 °C (900 °F) higher than that required to smelting, smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BC and the use of iron tools and weapons began to displace list of copper alloys, copper alloys – in some regions, only around 1200 BC. That event is considered the transition from the Bronze Age to the Iron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
(Butadiene)iron Tricarbonyl
(Butadiene)iron tricarbonyl is an organoiron compound with the formula (CH)Fe(CO). It is a well-studied metal complex of butadiene. An orange-colored viscous liquid that freezes just below room temperature, the compound adopts a piano stool structure. The complex was first prepared by heating iron pentacarbonyl with the diene. Related compounds Iron(0) complexes of conjugated dienes have been extensively studied. In the butadiene series, (η-CH)Fe(CO) and (η:η-CH)(Fe(CO)) have been crystallized. Many related complexes are known for substituted butadienes and related species. The species (η-isoprene)iron tricarbonyl is chiral. See also * Cyclobutadieneiron tricarbonyl Cyclobutadieneiron tricarbonyl is an organoiron compound with the formula Fe(C4H4)(CO)3. It is a yellow oil that is soluble in organic solvents. It has been used in organic chemistry as a precursor for cyclobutadiene, which is an elusive species i ... References External links * {{DEFAULTSORT:Butadienei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diphenylacetylene
Diphenylacetylene is the chemical compound C6H5C≡CC6H5. The molecule consists of two phenyl groups attached to a C2 unit. A colorless solid, it is used as a building block in organic synthesis and as a Transition metal alkyne complex, ligand in organometallic chemistry. Preparation and structure In one preparation for this compound, benzil is condensed with hydrazine to give the bis(hydrazone), which is oxidized with mercury(II) oxide. Alternatively stilbene is brominated, and the resulting dibromodiphenylethane is subjected to dehydrohalogenation. Yet another method involves the coupling of iodobenzene and the copper salt of phenylacetylene in the Castro-Stephens coupling. The related Sonogashira coupling involves the coupling of iodobenzene and phenylacetylene. Diphenylacetylene is a planar molecule. The central C≡C distance is 119.8 picometers. Derivatives 1,2,3,4-Tetraphenylbutadiene is prepared by reductive coupling of diphenylacetylene using lithium metal followed by h ... [...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] |
Reaction Mechanism
In chemistry, a reaction mechanism is the step by step sequence of elementary reactions by which overall chemical reaction occurs. A chemical mechanism is a theoretical conjecture that tries to describe in detail what takes place at each stage of an overall chemical reaction. The detailed steps of a reaction are not observable in most cases. The conjectured mechanism is chosen because it is thermodynamically feasible and has experimental support in isolated intermediates (see next section) or other quantitative and qualitative characteristics of the reaction. It also describes each reactive intermediate, activated complex, and transition state, which bonds are broken (and in what order), and which bonds are formed (and in what order). A complete mechanism must also explain the reason for the reactants and catalyst used, the stereochemistry observed in reactants and products, all products formed and the amount of each. The electron or arrow pushing method is often used in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mannich Reaction
In organic chemistry, the Mannich reaction is a three-component organic reaction that involves the amino alkylation of an acidic proton next to a carbonyl () functional group by formaldehyde () and a primary or secondary amine () or ammonia (). The final product is a β-amino-carbonyl compound also known as a Mannich base. Reactions between aldimines and α-methylene carbonyls are also considered Mannich reactions because these imines form between amines and aldehydes. The reaction is named after Carl Mannich. The Mannich reaction starts with the nucleophilic addition of an amine to a carbonyl group followed by dehydration to the Schiff base. The Schiff base is an electrophile which reacts in a second step in an electrophilic addition with an enol formed from a carbonyl compound containing an acidic alpha-proton. The Mannich reaction is a condensation reaction. In the Mannich reaction, primary or secondary amines or ammonia react with formaldehyde to form a Schiff base. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
