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Azobisisobutyronitrile
Azobisisobutyronitrile (abbreviated AIBN) is an organic compound with the formula . 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 °C and 72 °C.Cla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azo Compound
Azo compounds are organic compounds bearing the functional group diazenyl (, in which R and R′ can be either aryl or alkyl groups). IUPAC defines azo compounds as: "Derivatives of diazene (diimide), , wherein both hydrogens are substituted by hydrocarbyl groups, e.g. azobenzene or diphenyldiazene.", where Ph stands for phenyl group. The more stable derivatives contain two aryl groups. The group is called an ''azo group'' (, ). Many textile and leather articles are dyed with azo dyes and pigments. Aryl azo compounds urinary tract infections">Phenazopyridine, an aryl azo compound, is used to treat urinary tract infections">150px Aryl azo compounds are usually stable, crystalline species. Azobenzene is the prototypical aromatic azo compound. It exists mainly as the Cis-trans isomerism, ''trans'' isomer, but upon illumination, converts to the Cis-trans isomerism, ''cis'' isomer. Aromatic azo compounds can be synthesized by azo coupling, which entails an electrophilic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrazine
Hydrazine is an inorganic compound with the chemical formula . It is a simple pnictogen hydride, and is a colourless flammable liquid with an ammonia-like odour. Hydrazine is highly hazardous unless handled in solution as, for example, hydrazine hydrate (). Hydrazine is mainly used as a foaming agent in preparing Polymeric foam, polymer foams, but applications also include its uses as a precursor (chemistry), precursor to pharmaceuticals and agrochemicals, as well as a long-term storable propellant for in-outer space, space spacecraft propulsion. Additionally, hydrazine is used in various rocket propellant, rocket fuels and to prepare the gas precursors used in airbags. Hydrazine is used within both nuclear and conventional electrical power plant steam cycles as an oxygen scavenger to control concentrations of dissolved oxygen in an effort to reduce corrosion. , approximately 120,000 tons of hydrazine hydrate (corresponding to a 64% solution of hydrazine in water by weight) we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 It can also be synthesized by a reduction of tributyltin chloride with lithium aluminium hydride. 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 Bu3S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-containing compounds such as alkanes (e.g. methane ) and its derivatives are universally considered organic, but many others are sometimes considered inorganic, such as certain compounds of carbon with nitrogen and oxygen (e.g. cyanide ion , hydrogen cyanide , chloroformic acid , carbon dioxide , and carbonate ion ). Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, and even ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Markovnikov's Rule
In organic chemistry, Markovnikov's rule or Markownikoff's rule describes the outcome of some addition reactions. The rule was formulated by Russian chemist Vladimir Markovnikov in 1870. Explanation The rule states that with the addition of a protic acid HX or other polar reagent to an asymmetric alkene, the acid hydrogen (H) or electropositive part gets attached to the carbon with more hydrogen substituents, and the halide (X) group or electronegative part gets attached to the carbon with more alkyl substituents. This is in contrast to Markovnikov's original definition, in which the rule states that the X component is added to the carbon with the fewest hydrogen atoms while the hydrogen atom is added to the carbon with the greatest number of hydrogen atoms. The same is true when an alkene reacts with water in an additional reaction to form an alcohol that involves carbocation formation. The hydroxyl group (OH) bonds to the carbon that has the greater number of carbon-carbon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetramethylsuccinonitrile
Tetramethylsuccinonitrile or TMSN is an organic compound with the formula (C(CH3)2CN)2, classified as a dinitrile, and a colorless and odorless solid derived from 2,2'-azobis-isobutyronitrile, a common radical initiator in the manufacture of PVC: :. Because PVC is pervasive and can contain TMSN, the safety aspects of this dinitrile has generated interest. In regards to occupational exposures, the U.S. Occupational Safety and Health Administration and the U.S. National Institute for Occupational Safety and Health The National Institute for Occupational Safety and Health (NIOSH, ) is the List of United States federal agencies, United States federal agency responsible for conducting research and making recommendations for the prevention of work-related occ ... have set limits for dermal exposure at 3 mg/m3 over an eight-hour time-weighted average. References {{Reflist, 30em Alkanedinitriles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzoyl Peroxide
Benzoyl peroxide is a chemical compound (specifically, an organic peroxide) with structural formula , often abbreviated as (BzO)2. In terms of its structure, the molecule can be described as two benzoyl (, Bz) groups connected by a peroxide (). It is a white granular solid with a faint odour of benzaldehyde, poorly soluble in water but soluble in acetone, ethanol, and many other organic solvents. Benzoyl peroxide is an oxidizer, which is principally used in the production of polymers. Benzoyl peroxide is mainly used in production of plastics and for bleaching flour, hair, plastics and textiles. As a bleach, it has been used as a medication and a water disinfectant. As a medication, benzoyl peroxide is mostly used to treat acne, either alone or in combination with other treatments. Some versions are sold mixed with antibiotics such as clindamycin. It is on the World Health Organization's List of Essential Medicines. It is available as an over-the-counter and generic med ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ABCN
1,1′-Azobis(cyclohexanecarbonitrile) or ACHN is a radical initiator. The molecular formula is NCC6H10N=NC6H10CN. It is a white solid that is soluble in aromatic solvents. ACHN has a 10-hour half-life in toluene Toluene (), also known as toluol (), is a substituted aromatic hydrocarbon with the chemical formula , often abbreviated as , where Ph stands for the phenyl group. It is a colorless, water Water is an inorganic compound with the c ... at 88 °C. See also * Azobisisobutylonitrile (AIBN) is another commonly used free radical initiator References Azo compounds Nitriles Radical initiators {{Organic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetone Cyanohydrin
Acetone cyanohydrin (ACH) is an organic compound used in the production of methyl methacrylate, the monomer of the transparent plastic polymethyl methacrylate (PMMA), also known as acrylic. It liberates hydrogen cyanide easily, so it is used as a source of such. For this reason, this cyanohydrin is also highly toxic. Preparation In the laboratory, this compound may be prepared by treating sodium cyanide with acetone, followed by acidification: : Considering the high toxicity of acetone cyanohydrin, a lab scale production has been developed using a microreactor-scale flow chemistry to avoid needing to manufacture and store large quantities of the reagent. Alternatively, a simplified procedure involves the action of sodium or potassium cyanide on the sodium bisulfite adduct of acetone prepared ''in situ''. This gives a less pure product, one that is nonetheless suitable for most syntheses. Reactions Acetone cyanohydrin is an intermediate en route to methyl methacrylate. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrohalogenation Of Alkene Reaction
A hydrohalogenation reaction is the electrophilic addition of hydrogen halides like hydrogen chloride or hydrogen bromide to alkenes to yield the corresponding haloalkanes. : If the two carbon atoms at the double bond are linked to a different number of hydrogen atoms, the halogen is found preferentially at the carbon with fewer hydrogen substituents, an observation known as Markovnikov's rule. This is due to the abstraction of a hydrogen atom by the alkene from the hydrogen halide (HX) to form the most stable carbocation (relative stability: 3°>2°>1°>methyl), as well as generating a halogen anion. A simple example of a hydrochlorination is that of indene with hydrogen chloride gas (no solvent): : Alkynes also undergo hydrohalogenation reactions. Depending on the exact substrate, alkyne hydrohalogenation can proceed though a concerted protonation/nucleophilic attack (AdE3) or stepwise by first protonating the alkyne to form a vinyl cation, followed by attack of HX/X− to give ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrohalogenation
A hydrohalogenation reaction is the electrophilic addition of hydrogen halides like hydrogen chloride or hydrogen bromide to alkenes to yield the corresponding haloalkanes. : If the two carbon atoms at the double bond are linked to a different number of hydrogen atoms, the halogen is found preferentially at the carbon with fewer hydrogen substituents, an observation known as Markovnikov's rule. This is due to the abstraction of a hydrogen atom by the alkene from the hydrogen halide (HX) to form the most stable carbocation (relative stability: 3°>2°>1°>methyl), as well as generating a halogen anion. A simple example of a hydrochlorination is that of indene with hydrogen chloride gas (no solvent): : Alkynes also undergo hydrohalogenation reactions. Depending on the exact substrate, alkyne hydrohalogenation can proceed though a concerted protonation/nucleophilic attack (AdE3) or stepwise by first protonating the alkyne to form a vinyl cation, followed by attack of HX/X− to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
