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Chlorobenzene
Chlorobenzene is an aromatic organic compound with the chemical formula C6H5Cl. This colorless, flammable liquid is a common solvent and a widely used intermediate in the manufacture of other chemicals. Uses Historical The major use of chlorobenzene is as an intermediate in the production of herbicides, dyestuffs, and rubber. Chlorobenzene is also used as a high-boiling solvent in industrial applications as well as in the laboratory. Chlorobenzene is nitrated on a large scale to give a mixture of 2-nitrochlorobenzene and 4-nitrochlorobenzene, which are separated. These mononitrochlorobenzenes are converted to related 2-nitrophenol, 2-nitroanisole, bis(2-nitrophenyl)disulfide, and 2-nitroaniline by nucleophilic displacement of the chloride, with respectively sodium hydroxide, sodium methoxide, sodium disulfide, and ammonia. The conversions of the 4-nitro derivative are similar. Chlorobenzene once was used in the manufacture of pesticides, most notably DDT, by reaction wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bromobenzene
Bromobenzene is an aryl halide, C6H5Br. It is a colourless liquid although older samples can appear yellow. It is a reagent in organic synthesis. Synthesis and reactions Bromobenzene is prepared by the action of bromine on benzene in the presence of Lewis acid catalysts such as aluminium chloride or ferric bromide. Bromobenzene is used to introduce a phenyl group into other compounds. One method involves its conversion to the Grignard reagent, phenylmagnesium bromide. This reagent can be used, e.g. in the reaction with carbon dioxide to prepare benzoic acid. Other methods involve palladium-catalyzed coupling reactions, such as the Suzuki reaction. Bromobenzene is used as a precursor in the manufacture of phencyclidine. Toxicity Animal tests indicate low toxicity. Little is known about chronic effects. For liver toxicity, the 3,4-epoxide are proposed intermediates. See also *Fluorobenzene *Chlorobenzene *Iodobenzene Iodobenzene is an organoiodine compound consisting of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorobenzene
Fluorobenzene is the chemical compound with the formula C6H5F, often abbreviated PhF. A colorless liquid, it is a precursor to many fluorophenyl compounds. Preparation PhF was first reported in 1886 by O. Wallach at the University of Bonn, who prepared the compound in two steps. Phenyldiazonium chloride was first converted to a triazene using piperidine: : hN2l + 2 (CH2)5NH → PhN=N-N(CH2)5 + CH2)5NH2l The triazine was then cleaved with hydrofluoric acid: :PhN=N-N(CH2)5 + 2 HF → PhF + N2 + CH2)5NH2 Historical note: in Wallach's era, the element fluorine was symbolized with "Fl". Thus, his procedure is subtitled "Fluorbenzol, C6H5Fl". On the laboratory scale, PhF is prepared by the thermal decomposition of the benzenediazonium tetrafluoroborate: :PhN2BF4 → PhF + BF3 + N2 According to the procedure, solid hN2F4 is heated with a flame to initiate an exothermic reaction, which also affords boron trifluoride and nitrogen gas. Product PhF and BF3 a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aryne
Arynes and benzynes are highly reactive species derived from an aromatic ring by removal of two substituents. Arynes are examples of didehydroarenes (1,2-didehydroarenes in this case), although 1,3- and 1,4-didehydroarenes are also known. Arynes are examples of strained alkynes. Bonding in arynes The alkyne representation of benzyne is the most widely encountered. Arynes are usually described as having a strained triple bond. Geometric constraints on the triple bond in benzyne result in diminished overlap of in-plane p-orbitals, and thus weaker triple bond. The vibrational frequency of the triple bond in benzyne was assigned by Radziszewski to be 1846 cm−1, indicating a weaker triple bond than in unstrained alkyne with vibrational frequency of approximately 2150 cm−1. Nevertheless, benzyne is more like a strained alkyne than a diradical, as seen from the large singlet–triplet gap and alkyne-like reactivity. The LUMO of aryne lies much lower than the LUMO of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenol
Phenol (also called carbolic acid) is an aromatic organic compound with the molecular formula . It is a white crystalline solid that is volatile. The molecule consists of a phenyl group () bonded to a hydroxy group (). Mildly acidic, it requires careful handling because it can cause chemical burns. Phenol was first extracted from coal tar, but today is produced on a large scale (about 7 billion kg/year) from petroleum-derived feedstocks. It is an important industrial commodity as a precursor to many materials and useful compounds. It is primarily used to synthesize plastics and related materials. Phenol and its chemical derivatives are essential for production of polycarbonates, epoxies, Bakelite, nylon, detergents, herbicides such as phenoxy herbicides, and numerous pharmaceutical drugs. Properties Phenol is an organic compound appreciably soluble in water, with about 84.2 g dissolving in 1000 mL (0.895 M). Homogeneous mixtures of phenol and water ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solvent
A solvent (s) (from the Latin '' solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for polar molecules and the most common solvent used by living things; all the ions and proteins in a cell are dissolved in water within the cell. The quantity of solute that can dissolve in a specific volume of solvent varies with temperature. Major uses of solvents are in paints, paint removers, inks, and dry cleaning. Specific uses for organic solvents are in dry cleaning (e.g. tetrachloroethylene); as paint thinners ( toluene, turpentine); as nail polish removers and solvents of glue (acetone, methyl acetate, ethyl acetate); in spot removers ( hexane, petrol ether); in detergents ( citrus terpenes); and in perfumes (ethanol). Solvents find various applications in chemical, pharmaceutical, oil, and gas industries, including in chemic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,4-Dichlorobenzene
1,4-Dichlorobenzene (1,4-DCB, ''p''-DCB, or ''para''-dichlorobenzene, sometimes abbreviated as PDCB or para) is an organic compound with the formula C6H4Cl2. This colorless solid has a strong odor. The molecule consists of a benzene ring with two chlorine atoms (replacing hydrogen atoms) on opposing sites of the ring. It is used as a disinfectant, pesticide, and deodorant, most familiarly in mothballs in which it is a replacement for the more traditional naphthalene because of naphthalene's greater flammability (though both chemicals have the same NFPA 704 rating). It is also used as a precursor in the production of the chemically and thermally resistant polymer poly(''p''-phenylene sulfide). Production ''p''-DCB is produced by chlorination of benzene using ferric chloride as a catalyst: :C6H6 + 2 Cl2 → C6H4Cl2 + 2 HCl The chief impurity is the 1,2 isomer. The compound can be purified by fractional crystallization, taking advantage of its relatively high melt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dichlorobenzene
There are three distinct chemical compounds which are dichlorobenzenes: * 1,2-Dichlorobenzene or ''ortho''-dichlorobenzene; *1,3-Dichlorobenzene or ''meta''-dichlorobenzene; *1,4-Dichlorobenzene or ''para''-dichlorobenzene. All three isomers are colorless organic compounds with the formula CHCl. They differ structurally based on where the two chlorine atoms are attached to the ring, like bracelets with two beads of one color and four beads of another color. Biodegradation '' Rhodococcus phenolicus'' is a bacterium species able to degrade dichlorobenzene as its sole carbon Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon ma ... source. References {{Authority control Chlorobenzenes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzene
Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, benzene is classed as a hydrocarbon. Benzene is a natural constituent of petroleum and is one of the elementary petrochemicals. Due to the cyclic continuous pi bonds between the carbon atoms, benzene is classed as an aromatic hydrocarbon. Benzene is a colorless and highly flammable liquid with a sweet smell, and is partially responsible for the aroma of gasoline. It is used primarily as a precursor to the manufacture of chemicals with more complex structure, such as ethylbenzene and cumene, of which billions of kilograms are produced annually. Although benzene is a major industrial chemical, it finds limited use in consumer items because of its toxicity. History Discovery The word "''benzene''" derives from "''gum benzoin''" ( ben ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodobenzene
Iodobenzene is an organoiodine compound consisting of a benzene ring substituted with one iodine atom. It is useful as a synthetic intermediate in organic chemistry. It is a volatile colorless liquid, although aged samples appear yellowish. Preparation Iodobenzene is commercially available, but it can be prepared in the laboratory from aniline via the Diazotization Reaction. In the first step, the amine functional group is diazotized with hydrochloric acid and sodium nitrite. Potassium iodide is added to the resultant phenyldiazonium chloride, causing nitrogen gas to evolve. The product is separated by steam distillation. : Alternatively, it can be produced by refluxing iodine and nitric acid with benzene. Reactions Since the C–I bond is weaker than C–Br or C–Cl, iodobenzene is more reactive than bromobenzene or chlorobenzene. Iodobenzene reacts readily with magnesium to form the Grignard reagent, phenylmagnesium iodide. Phenylmagnesium iodide, like the bromide ana ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorination Benzene , a method of water treatment
{{disambiguation ...
Chlorination may refer to: * Chlorination reaction, a halogenation reaction using chlorine * Water chlorination Water chlorination is the process of adding chlorine or chlorine compounds such as sodium hypochlorite to water. This method is used to kill bacteria, viruses and other microbes in water. In particular, chlorination is used to prevent the spr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aluminium Chloride
Aluminium chloride, also known as aluminium trichloride, is an inorganic compound with the formula . It forms hexahydrate with the formula , containing six water molecules of hydration. Both are colourless crystals, but samples are often contaminated with iron(III) chloride, giving a yellow color. The anhydrous material is important commercially. It has a low melting and boiling point. It is mainly produced and consumed in the production of aluminium metal, but large amounts are also used in other areas of the chemical industry. The compound is often cited as a Lewis acid. It is an example of an inorganic compound that reversibly changes from a polymer to a monomer at mild temperature. Structure Anhydrous adopts three structures, depending on the temperature and the state (solid, liquid, gas). Solid has a sheet-like layered structure with cubic close-packed chloride ions. In this framework, the Al centres exhibit octahedral coordination geometry. In contrast, has a more ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfur Dichloride
Sulfur dichloride is the chemical compound with the formula . This cherry-red liquid is the simplest sulfur chloride and one of the most common, and it is used as a precursor to organosulfur compounds. It is a highly corrosive and toxic substance, and it reacts on contact with water to form chlorine-containing acids. Chlorination of sulfur is produced by the chlorination of either elemental sulfur or disulfur dichloride. The process occurs in a series of steps, some of which are: :; ''ΔH'' = −58.2 kJ/mol :; ''ΔH'' = −40.6 kJ/mol The addition of to has been proposed to proceed via a mixed valence intermediate . undergoes even further chlorination to give , but this species is unstable at near room temperature. It is likely that several exist where ''n'' > 2. Disulfur dichloride, , is the most common impurity in . Separation of from is possible via distillation with to form an azeotrope of 99% purity, however sulfur dichloride loses chlorine slowly at room temper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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