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Tributyltin Hydride
Tributyltin hydride is an organotin compound with the formula (C4H9)3SnH. It is a colorless liquid that is soluble in organic solvents. The compound is used as a source of hydrogen atoms in organic synthesis. Synthesis and characterization The compound is produced by reduction of tributyltin oxide with polymethylhydrosiloxane: : 2 " eSi(H)Osub>n" + (Bu3Sn)2O → "eSi(OH)Osub>n" + 2 Bu3SnH The hydride is a distillable liquid that is mildly sensitive to air, decomposing to (Bu3Sn)2O. Its IR spectrum exhibits a strong band at 1814 cm−1 for ''ν''Sn−H. Applications It is a specialized reagent in organic synthesis. Combined with azobisisobutyronitrile (AIBN) or by irradiation with light, tributyltin hydride converts organic halides (and related groups) to the corresponding hydrocarbon. This process occurs via a radical chain mechanism involving the radical Bu3Sn•. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organotin Compound
Organotin compounds or stannanes are chemical compounds based on tin with hydrocarbon substituents. Organotin chemistry is part of the wider field of organometallic chemistry. The first organotin compound was diethyltin diiodide (), discovered by Edward Frankland in 1849. The area grew rapidly in the 1900s, especially after the discovery of the Grignard reagents, which are useful for producing Sn–C bonds. The area remains rich with many applications in industry and continuing activity in the research laboratory. Structure Organotin compounds are generally classified according to their oxidation states. Tin(IV) compounds are much more common and more useful. Organic derivatives of tin(IV) The tetraorgano derivatives are invariably tetrahedral. Compounds of the type SnRR'R''R have been resolved into individual enantiomers. Organotin halides Organotin chlorides have the formula for values of ''n'' up to 3. Bromides, iodides, and fluorides are also known but less important. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Synthesis
Organic synthesis is a special branch of chemical synthesis and is concerned with the intentional construction of organic compounds. Organic molecules are often more complex than inorganic compounds, and their synthesis has developed into one of the most important branches of organic chemistry. There are several main areas of research within the general area of organic synthesis: '' total synthesis'', ''semisynthesis'', and ''methodology''. Total synthesis A total synthesis is the complete chemical synthesis of complex organic molecules from simple, commercially available petrochemical or natural precursors. Total synthesis may be accomplished either via a linear or convergent approach. In a ''linear'' synthesis—often adequate for simple structures—several steps are performed one after another until the molecule is complete; the chemical compounds made in each step are called synthetic intermediates. Most often, each step in a synthesis refers to a separate rea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tributyltin Oxide
Tributyltin oxide (TBTO) is an organotin compound chiefly used as a biocide (fungicide and molluscicide), especially a wood preservative. Its chemical formula is C4H9)3Snsub>2O. It is a colorless viscous liquid. It is poorly soluble in water (20 ppm) but highly soluble in organic solvents. It is a potent skin irritant. Historically, tributyltin oxide's biggest application was as a marine anti-biofouling agent. Concerns over toxicity of these compounds have led to a worldwide ban by the International Maritime Organization. It is now considered a severe marine pollutant A pollutant or novel entity is a substance or energy introduced into the environment that has undesired effects, or adversely affects the usefulness of a resource. These can be both naturally forming (i.e. minerals or extracted compounds like o ... and a Substance of Very High Concern by the EU.Organotin Chemistry, Second Edition. Alwyn G. Davies, 2004, Wiley-VCH Verlag GmbH & Co. KGaA. Today, it is mainly u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IR Spectrum
Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) is the measurement of the interaction of infrared radiation with matter by absorption, emission, or reflection. It is used to study and identify chemical substances or functional groups in solid, liquid, or gaseous forms. It can be used to characterize new materials or identify and verify known and unknown samples. The method or technique of infrared spectroscopy is conducted with an instrument called an infrared spectrometer (or spectrophotometer) which produces an infrared spectrum. An IR spectrum can be visualized in a graph of infrared light absorbance (or transmittance) on the vertical axis vs. frequency, wavenumber or wavelength on the horizontal axis. Typical units of wavenumber used in IR spectra are reciprocal centimeters, with the symbol cm−1. Units of IR wavelength are commonly given in micrometers (formerly called "microns"), symbol μm, which are related to the wavenumber in a reciprocal way. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azobisisobutyronitrile
Azobisisobutyronitrile (abbreviated AIBN) is an organic compound with the formula CH3)2C(CN)sub>2N2. This white powder is soluble in alcohols and common organic solvents but is insoluble in water. It is often used as a foamer in plastics and rubber and as a radical initiator. As an azo initiator, radicals resulting from AIBN have multiple benefits over common organic peroxides. For example, they do not have oxygenated byproducts or much yellow discoloration. Additionally, they do not cause too much grafting and therefore are often used when making adhesives, acrylic fibers, detergents, etc. Mechanism of decomposition In its most characteristic reaction, AIBN decomposes, eliminating a molecule of nitrogen gas to form two 2-cyanoprop-2-yl radicals: : Because azobisisobutyronitrile readily gives off free radicals, it is often used as a radical initiator. This happens at temperatures above 40 °C, but in experiments is more commonly done at temperatures between 66&nb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrostannylation
In chemistry, hydrostannylation is the insertion of unsaturated substrates into an Sn-H bond. The reaction occurs under free-radical conditions, but the stereochemistry and regiochemistry are often complex. The reaction gained synthetic importance with the discovery that palladium complexes catalyze the reaction. The reaction is analogous to hydrosilylation and is a subset of hydroelementation. Hydrostannylation is a versatile route to organotin compounds, many of which are versatile synthetic intermediates, e.g. in Stille coupling. Substrates and scope The typical Pd-based catalyst is tetrakis(triphenylphosphine)palladium(0). The typical unsaturated substrates are alkynes. The typical stannane is tributyltin hydride. The reaction mechanism is assumed to operate via oxidative addition Oxidative addition and reductive elimination are two important and related classes of reactions in organometallic chemistry. Oxidative addition is a process that increases both the oxidatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tributyltin
Tributyltin (TBT) is an umbrella term for a class of organotin compounds which contain the (C4H9)3 Sn group, with a prominent example being tributyltin oxide. For 40 years TBT was used as a biocide in anti-fouling paint, commonly known as bottom paint, applied to the hulls of oceangoing vessels. Bottom paint improves ship performance and durability as it reduces the rate of biofouling, the growth of organisms on the ship's hull. The TBT slowly leaches out into the marine environment where it is highly toxic toward nontarget organisms. TBT toxicity can lead to biomagnification or bioaccumulation within such nontarget organisms like invertebrates, vertebrates, and a variety of mammals. TBT is also an obesogen. After it led to collapse of local populations of organisms, TBT was banned. Chemical properties TBT, or tributyltin, tributylstannyl or tributyl stannic hydride compounds are organotin compounds. They have three butyl groups covalently bonded to a tin(IV) centre.Davies, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trimethylsilyl
A trimethylsilyl group (abbreviated TMS) is a functional group in organic chemistry. This group consists of three methyl groups bonded to a silicon atom minus;Si(CH3)3 which is in turn bonded to the rest of a molecule. This structural group is characterized by chemical inertness and a large molecular volume, which makes it useful in a number of applications. A trimethylsilyl group bonded to a methyl group forms tetramethylsilane, which is abbreviated as TMS as well. Compounds with trimethylsilyl groups are not normally found in nature. Chemists sometimes use a trimethylsilylating reagent to derivatize rather non-volatile compounds such as certain alcohols, phenols, or carboxylic acids by substituting a trimethylsilyl group for a hydrogen in the hydroxyl groups on the compounds. This way trimethylsiloxy groups minus;O-Si(CH3)3are formed on the molecule. A couple of examples of trimethylsilylating agents include trimethylsilyl chloride and bis(trimethylsilyl)acetamide. Tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organotin Compounds
Organotin compounds or stannanes are chemical compounds based on tin with hydrocarbon substituents. Organotin chemistry is part of the wider field of organometallic chemistry. The first organotin compound was diethyltin diiodide (), discovered by Edward Frankland in 1849. The area grew rapidly in the 1900s, especially after the discovery of the Grignard reagents, which are useful for producing Sn–C bonds. The area remains rich with many applications in industry and continuing activity in the research laboratory. Structure Organotin compounds are generally classified according to their oxidation states. Tin(IV) compounds are much more common and more useful. Organic derivatives of tin(IV) The tetraorgano derivatives are invariably tetrahedral. Compounds of the type SnRR'R''R have been resolved into individual enantiomers. Organotin halides Organotin chlorides have the formula for values of ''n'' up to 3. Bromides, iodides, and fluorides are also known but less important. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radical Initiators
Radical may refer to: Politics and ideology Politics *Radical politics, the political intent of fundamental societal change *Radicalism (historical), the Radical Movement that began in late 18th century Britain and spread to continental Europe and Latin America in the 19th century *Radical Party (other), several political parties *Radicals (UK), a British and Irish grouping in the early to mid-19th century * Radicalization Ideologies *Radical chic, a term coined by Tom Wolfe to describe the pretentious adoption of radical causes *Radical feminism, a perspective within feminism that focuses on patriarchy * Radical Islam, or Islamic extremism *Radical veganism, a radical interpretation of veganism, usually combined with anarchism *Radical Reformation, an Anabaptist movement concurrent with the Protestant Reformation Science and mathematics Science *Radical (chemistry), an atom, molecule, or ion with unpaired valence electron(s) *Radical surgery, where diseased tissue or lym ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metal Hydrides
In chemistry, a hydride is formally the anion of hydrogen( H−). The term is applied loosely. At one extreme, all compounds containing covalently bound H atoms are called hydrides: water (H2O) is a hydride of oxygen, ammonia is a hydride of nitrogen, etc. For inorganic chemists, hydrides refer to compounds and ions in which hydrogen is covalently attached to a less electronegative element. In such cases, the H centre has nucleophilic character, which contrasts with the protic character of acids. The hydride anion is very rarely observed. Almost all of the elements form binary compounds with hydrogen, the exceptions being He, Ne, Ar, Kr, Pm, Os, Ir, Rn, Fr, and Ra. Exotic molecules such as positronium hydride have also been made. Bonds Bonds between hydrogen and the other elements range from highly to somewhat covalent. Some hydrides, e.g. boron hydrides, do not conform to classical electron-counting rules and the bonding is described in terms of multi-cente ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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