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Vinylation
in organic chemistry, vinylation is the process of attaching a vinyl group () to a substrate. Many organic compounds contain vinyl groups, so the process has attracted significant interest, especially since the reaction scope includes substituted vinyl groups. The reactions can be classified according to the source of the vinyl group. Nucleophilic vinyl reagents Vinyl lithium and vinyl magnesium bromide are sources of "", which add to ketones and aldehydes. Vinylsiloxane and vinylboranes have also been used as sources of vinyl anion equivalents.These types of reactions require catalysts such as those based on palladium. Vinylation with alkenes The Heck reaction couples an unsaturated halide with an alkene. Base and a palladium catalyst are required. This reaction is a way to substitute alkenes. In hydrovinylation, ethylene adds "across" an alkene double bond: : This kind of reaction requires a metal catalyst. In principle, alkenes other than ethylene could be employed. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkene
In organic chemistry, an alkene is a hydrocarbon containing a carbon–carbon double bond. Alkene is often used as synonym of olefin, that is, any hydrocarbon containing one or more double bonds.H. Stephen Stoker (2015): General, Organic, and Biological Chemistry'. 1232 pages. Two general types of monoalkenes are distinguished: terminal and internal. Also called α-olefins, terminal alkenes are more useful. However, the International Union of Pure and Applied Chemistry (IUPAC) recommends using the name "alkene" only for acyclic hydrocarbons with just one double bond; alkadiene, alkatriene, etc., or polyene for acyclic hydrocarbons with two or more double bonds; cycloalkene, cycloalkadiene, etc. for cyclic ones; and "olefin" for the general class – cyclic or acyclic, with one or more double bonds. Acyclic alkenes, with only one double bond and no other functional groups (also known as mono-enes) form a homologous series of hydrocarbons with the general formula wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vinyl Formate
Vinyl formate is an organic compound with the formula . It is the ester formally derived from formic acid and vinyl alcohol. Although rare commercially, it occurs naturally. It can be prepared by transvinylation in organic chemistry, vinylation is the process of attaching a vinyl group () to a substrate. Many organic compounds contain vinyl groups, so the process has attracted significant interest, especially since the reaction scope includes substituted v ..., say by treating vinyl versatate with formic acid in the presence of a mercury(II) catalyst..{{cite journal , doi=10.1016/S0040-4020(01)97407-1, title=A novel synthesis of vinyl esters from vinylversatate-10 , year=1974 , last1=Mondal , first1=M.A.S. , last2=Van Der Meer , first2=R. , last3=German , first3=A.L. , last4=Heikens , first4=D. , journal=Tetrahedron , volume=30 , issue=23–24 , pages=4205–4207 References Monomers Vinyl esters Formates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heck Reaction
The Heck reaction (also called the Mizoroki–Heck reaction) is the chemical reaction of an unsaturated halide (or triflate) with an alkene in the presence of a base and a palladium catalyst (or palladium nanomaterial-based catalyst) to form a substituted alkene. It is named after Tsutomu Mizoroki and Richard F. Heck. Heck was awarded the 2010 Nobel Prize in Chemistry, which he shared with Ei-ichi Negishi and Akira Suzuki, for the discovery and development of this reaction. This reaction was the first example of a carbon-carbon bond-forming reaction that followed a Pd(0)/Pd(II) catalytic cycle, the same catalytic cycle that is seen in other Pd(0)-catalyzed cross-coupling reactions. The Heck reaction is a way to substitute alkenes. History The original reaction by Tsutomu Mizoroki (1971) describes the coupling between iodobenzene and styrene in methanol to form stilbene at 120 °C (autoclave) with potassium acetate base and palladium chloride catalysis. This work was a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethylene
Ethylene ( IUPAC name: ethene) is a hydrocarbon which has the formula or . It is a colourless, flammable gas with a faint "sweet and musky" odour when pure. It is the simplest alkene (a hydrocarbon with carbon-carbon double bonds). Ethylene is widely used in the chemical industry, and its worldwide production (over 150 million tonnes in 2016) exceeds that of any other organic compound. Much of this production goes toward polyethylene, a widely used plastic containing polymer chains of ethylene units in various chain lengths. Ethylene is also an important natural plant hormone and is used in agriculture to force the ripening of fruits. The hydrate of ethylene is ethanol. Structure and properties This hydrocarbon has four hydrogen atoms bound to a pair of carbon atoms that are connected by a double bond. All six atoms that comprise ethylene are coplanar. The H-C-H angle is 117.4°, close to the 120° for ideal sp² hybridized carbon. The molecule is also relatively weak: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Chemistry
Organic chemistry is a subdiscipline within chemistry involving the science, scientific study of the structure, properties, and reactions of organic compounds and organic materials, i.e., matter in its various forms that contain carbon atoms.Clayden, J.; Greeves, N. and Warren, S. (2012) ''Organic Chemistry''. Oxford University Press. pp. 1–15. . Study of structure determines their structural formula. Study of properties includes Physical property, physical and Chemical property, chemical properties, and evaluation of Reactivity (chemistry), chemical reactivity to understand their behavior. The study of organic reactions includes the organic synthesis, chemical synthesis of natural products, drugs, and polymers, and study of individual organic molecules in the laboratory and via theoretical (in silico) study. The range of chemicals studied in organic chemistry includes hydrocarbons (compounds containing only carbon and hydrogen) as well as compounds based on carbon, but also con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vinyl Sulfide
Divinyl sulfide is the organosulfur compound with the formula S(CH=CH2)2. It is a colorless liquid with a faint odor. It is found in the oil of some species of ''Allium''. It is notable as the product from hydrogen sulfide and acetylene, a combination that arises when acetylene is generated by hydrolysis of technical-grade calcium carbide, which contains impurities of calcium sulfide. Divinylsulfide was first prepared in 1920 by the reaction of sulfur mustard with sodium ethoxide Sodium ethoxide, also referred to as sodium ethylate, is the ionic, organic compound with the formula , or NaOEt (Et = ethane). It is a white solid, although impure samples appear yellow or brown. It dissolves in polar solvents such as ethanol. ...: :(ClCH2CH2)2S + 2 NaOEt → (CH2=CH)2S + 2 EtOH + 2 NaCl A variety of monovinyl sulfides are known, often arising from the reactions of thiols and acetylenes. References {{reflist Thioethers Vinyl compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vinyl Acetate
Vinyl acetate is an organic compound with the formula CH3CO2CH=CH2. This colorless liquid is the precursor to polyvinyl acetate and ethene-vinyl acetate copolymers, important industrial polymers. Production The worldwide production capacity of vinyl acetate was estimated at 6,969,000 tonnes/year in 2007, with most capacity concentrated in the United States (1,585,000 all in Texas), China (1,261,000), Japan (725,000) and Taiwan (650,000). The average list price for 2008 was US$1600/tonne. Celanese is the largest producer (ca 25% of the worldwide capacity), while other significant producers include China Petrochemical Corporation (7%), Chang Chun Group (6%), and LyondellBasell (5%). It is a key ingredient in furniture glue. Preparation Vinyl acetate is the acetate ester of vinyl alcohol. Since vinyl alcohol is highly unstable (with respect to acetaldehyde), the preparation of vinyl acetate is more complex than the synthesis of other acetate esters. The major industrial ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transesterification
In organic chemistry, transesterification is the process of exchanging the organic group R″ of an ester with the organic group R' of an alcohol. These reactions are often catalyzed by the addition of an acid or base catalyst. The reaction can also be accomplished with the help of other enzymes, particularly lipases (one example is the lipase E.C.3.1.1.3). Strong acids catalyse the reaction by donating a proton to the carbonyl group, thus making it a more potent electrophile, whereas bases catalyse the reaction by removing a proton from the alcohol, thus making it more nucleophilic. If the alcohol produced by the reaction can be separated from the reactants by distillation this will drive the equilibrium toward the products, this means that esters with larger alkoxy groups can be made from methyl or ethyl esters in high purity by heating the mixture of ester, acid/base, and large alcohol. Mechanism In the transesterification mechanism, the carbonyl carbon of the starting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iridium
Iridium is a chemical element with the symbol Ir and atomic number 77. A very hard, brittle, silvery-white transition metal of the platinum group, it is considered the second-densest naturally occurring metal (after osmium) with a density of as defined by experimental X-ray crystallography. It is one of the most corrosion-resistant metals, even at temperatures as high as . However, corrosion-resistance is not quantifiable in absolute terms; although only certain molten salts and halogens are corrosive to solid iridium, finely divided iridium dust is much more reactive and can be flammable, whereas gold dust is not flammable but can be attacked by substances that iridium resists, such as aqua regia. Iridium was discovered in 1803 among insoluble impurities in natural platinum. Smithson Tennant, the primary discoverer, named it after the Greek goddess Iris, personification of the rainbow, because of the striking and diverse colors of its salts. Iridium is one of the rarest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vinyl Acetate
Vinyl acetate is an organic compound with the formula CH3CO2CH=CH2. This colorless liquid is the precursor to polyvinyl acetate and ethene-vinyl acetate copolymers, important industrial polymers. Production The worldwide production capacity of vinyl acetate was estimated at 6,969,000 tonnes/year in 2007, with most capacity concentrated in the United States (1,585,000 all in Texas), China (1,261,000), Japan (725,000) and Taiwan (650,000). The average list price for 2008 was US$1600/tonne. Celanese is the largest producer (ca 25% of the worldwide capacity), while other significant producers include China Petrochemical Corporation (7%), Chang Chun Group (6%), and LyondellBasell (5%). It is a key ingredient in furniture glue. Preparation Vinyl acetate is the acetate ester of vinyl alcohol. Since vinyl alcohol is highly unstable (with respect to acetaldehyde), the preparation of vinyl acetate is more complex than the synthesis of other acetate esters. The major industrial ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vinyl Ester
left, 144px, Vinyl acetate is a commercially important monomer that is classified as a vinyl ester (i.e. an ester of vinyl alcohol). Vinyl ester refers to esters formerly derived from vinyl alcohol. Commercially important examples of these monomers are vinyl acetate, vinyl propionate Vinyl propionate is the organic compound with the formula CH3CH2CO2CH=CH2. This colorless liquid is the ester of propionic acid and vinyl alcohol. It is used to produce poly(vinyl propionate) as well as copolymers with acrylate esters, vinyl chl ..., and vinyl laurate.{{cite encyclopedia, author=G. Roscher, title=Ullmann's Encyclopedia of Industrial Chemistry, chapter=Vinyl Esters, encyclopedia=Ullmann's Encyclopedia of Chemical Technology, year=2007, publisher=Wiley-VCH, location=Weinheim, doi=10.1002/14356007.a27_419, isbn=978-3527306732 References Monomers Commodity chemicals Vinyl compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
