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Étard Reaction
The Étard reaction is a chemical reaction that involves the direct oxidation of an aromatic or heterocyclic bound methyl group to an aldehyde using chromyl chloride. For example, toluene can be oxidized to benzaldehyde. It is named for the French chemist Alexandre Léon Étard (5 January 1852, Alençon – 1 May 1910). Reaction mechanism The reaction mechanism proceeds via an ene reaction with chromyl chloride, forming the precipitated Étard complex. The Étard complex is then decomposed by a [2,3] sigmatropic rearrangement under reducing conditions to prevent further oxidation to a carboxylic acid. Reducing conditions for the decomposition of the Étard complex are provided by saturated aqueous sodium sulphite. Typical solvents for the reaction include carbon disulfide, dichloromethane, chloroform, and carbon tetrachloride, with carbon tetrachloride being the most common. To obtain a highly purified aldehyde product, the Étard complex precipitate is often purified before d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexandre Léon Étard
Alexandre may refer to: * Alexandre (given name) * Alexandre (surname) * Alexandre (film) See also * Alexander * Alexandra (other) * Xano (other), a Portuguese hypocoristic of the name "Alexandre" {{Disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dichloromethane
Dichloromethane (DCM, methylene chloride, or methylene bichloride) is an organochlorine compound with the formula . This colorless, volatile liquid with a chloroform-like, sweet odor is widely used as a solvent. Although it is not miscible with water, it is slightly polar, and miscible with many organic solvents.Rossberg, M. ''et al.'' (2006) "Chlorinated Hydrocarbons" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim. . Occurrence Natural sources of dichloromethane include oceanic sources, macroalgae, wetlands, and volcanoes. However, the majority of dichloromethane in the environment is the result of industrial emissions. Production DCM is produced by treating either chloromethane or methane with chlorine gas at 400–500 °C. At these temperatures, both methane and chloromethane undergo a series of reactions producing progressively more chlorinated products. In this way, an estimated 400,000 tons were produced in the US, Europe, and Japan in 199 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitroethane
Nitroethane is an organic compound having the chemical formula C2H5NO2. Similar in many regards to nitromethane, nitroethane is an oily liquid at standard temperature and pressure. Pure nitroethane is colorless and has a fruity odor. Preparation Nitroethane is produced industrially by treating propane with nitric acid at 350–450 °C. This exothermic reaction produces four industrially significant nitroalkanes: nitromethane, nitroethane, 1-nitropropane, and 2-Nitropropane, 2-nitropropane. The reaction involves free radicals, such as CH3CH2CH2O., which arise via homolysis of the corresponding nitrite ester. These alkoxy radicals are susceptible to C—C fragmentation reactions, which explains the formation of a mixture of products.Sheldon B. Markofsky “Nitro Compounds, Aliphatic” in ''Ullmann's Encyclopedia of Industrial Chemistry'', Wiley-VCH, Weinheim, 2002. . Alternatively, nitroethane can be produced by the Victor Meyer reaction of haloethanes such as chloroeth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ephedrine
Ephedrine is a central nervous system (CNS) stimulant and sympathomimetic agent that is often used to prevent hypotension, low blood pressure during anesthesia. It has also been used for asthma, narcolepsy, and obesity but is not the preferred treatment. It is of unclear benefit in nasal congestion. It can be taken oral administration, by mouth or by intramuscular, injection into a muscle, intravenous, vein, or subcutaneous injection, just under the skin. Onset with intravenous use is fast, while injection into a muscle can take 20minutes, and by mouth can take an hour for effect. When given by injection, it lasts about an hour, and when taken by mouth, it can last up to four hours. Common side effects include insomnia, trouble sleeping, anxiety, headache, hallucinations, hypertension, high blood pressure, tachycardia, fast heart rate, decreased appetite, loss of appetite, and urinary retention. Serious side effects include stroke and myocardial infarction, heart attack. While ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldol Condensation
An aldol condensation is a condensation reaction in organic chemistry in which two carbonyl moieties (of aldehydes or ketones) react to form a β-hydroxyaldehyde or β-hydroxyketone (an aldol reaction), and this is then followed by dehydration to give a conjugated enone. The overall reaction equation is as follows (where the Rs can be H) Aldol condensations are important in organic synthesis and biochemistry as ways to form carbon–carbon bonds. In its usual form, it involves the nucleophilic addition of a ketone enolate to an aldehyde to form a β-hydroxy ketone, or aldol (aldehyde + alcohol), a structural unit found in many naturally occurring molecules and pharmaceuticals. The term ''aldol condensation'' is also commonly used, especially in biochemistry, to refer to just the first (addition) stage of the process—the aldol reaction itself—as catalyzed by aldolases. However, the first step is formally an addition reaction rather than a condensation reaction bec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Dichromate
Potassium dichromate is the inorganic compound with the formula . An orange solid, it is used in diverse laboratory and industrial applications. As with all hexavalent chromium compounds, it is chronically harmful to health. It is a crystalline ionic solid with a very bright, red-orange color. The salt is popular in laboratories because it is not deliquescent, in contrast to the more industrially relevant salt sodium dichromate.Gerd Anger, Jost Halstenberg, Klaus Hochgeschwender, Christoph Scherhag, Ulrich Korallus, Herbert Knopf, Peter Schmidt, Manfred Ohlinger, "Chromium Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. Production Potassium dichromate is usually prepared by the reaction of sodium dichromate and potassium chloride. Alternatively, it can be also obtained from potassium chromate by roasting chromite ore with potassium hydroxide: : Structure The solid crystallizes as two polymorphs. These salts are soluble in water, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Permanganate
Potassium permanganate is an inorganic compound with the chemical formula KMnO4. It is a purplish-black crystalline salt, which dissolves in water as K+ and ions to give an intensely pink to purple solution. Potassium permanganate is widely used in the chemical industry and laboratories as a strong oxidizing agent, and also as a medication for dermatitis, for cleaning wounds, and general disinfection. It is commonly used as a biocide for water treatment purposes. It is on the World Health Organization's List of Essential Medicines. In 2000, worldwide production was estimated at 30,000 tons. Properties Potassium permanganate is the potassium salt of the tetrahedral transition metal oxo complex permanganate, in which four ligands are bound to a manganese(VII) center. Structure forms orthorhombic crystals with constants: ''a'' = 910.5 pm, ''b'' = 572.0 pm, ''c'' = 742.5 pm. The overall motif is similar to that for barium sulfate, with which it forms solid so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decalin
Decalin (decahydronaphthalene, also known as bicyclo .4.0ecane and sometimes decaline), a bicyclic organic compound, is an industrial solvent. A colorless liquid with an aromatic odor, it is used as a solvent for many resins or fuel additives. Isomers Decalin occurs in ''cis'' and ''trans'' forms. The ''trans'' form is energetically more stable because of fewer steric interactions. ''cis''-Decalin is a chiral molecule without a chiral center; it has a two-fold rotational symmetry axis, but no reflective symmetry. However, the chirality is canceled through a chair-flipping process that turns the molecule into its mirror image. Image:Cis-trans isomerism of decahydronaphthalene.svg, Image:cis-decalin double chair.png, 2: Image:trans-decalin double chair.png, 3: File:Cisdecalin conformations.png, 4: ''trans''-Decalin The only possible way to join the two six-membered rings in the ''trans'' position means the second ring needs to start from two equatorial bonds (blue) of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzyl Methyl Ketone
Phenylacetone, also known as phenyl-2-propanone, is an organic compound with the chemical formula C6H5CH2COCH3. It is a colorless oil that is soluble in organic solvents. It is a mono-substituted benzene derivative, consisting of an acetone attached to a phenyl group. As such, its systematic IUPAC name is 1-phenyl-2-propanone. This substance is used in the manufacture of methamphetamine and amphetamine, where it is commonly known as P2P. Due to illicit drug labs using phenylacetone to make amphetamines, phenylacetone was declared a schedule II controlled substance in the United States in 1980. In humans, phenylacetone occurs as a metabolite of amphetamine and methamphetamine via FMO3-mediated oxidative deamination. Synthesis There are many routes to synthesize phenylacetone. Industry uses the gas-phase ketonic decarboxylation of phenylacetic acid using acetic acid over a ceria-alumina solid acid catalyst. A related laboratory-scale reaction has been described. An alternativ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propiophenone
Propiophenone (shorthand: benzoylethane or BzEt) is an aryl ketone. It is a colorless, sweet-smelling liquid that is insoluble in water, but miscible with organic solvents. It is used in the preparation of other compounds. Production Propiophenone can be prepared by Friedel–Crafts reaction of propanoyl chloride and benzene. It is also prepared commercially by ketonization of benzoic acid and propionic acid over calcium acetate and alumina at 450–550 °C: :C6H5CO2H + CH3CH2CO2H → C6H5C(O)CH2CH3 + CO2 + H2O Ludwig Claisen discovered that Alpha and beta carbon, α-methoxystyrene forms this compound when heated for an hour at 300 °C (65% yield). Uses file:Phenmetrazine.svg, 120px, left, Phenmetrazine, derived from propiophenone, is an appetite suppressant. It is an intermediate in the synthesis of the pharmaceuticals phenmetrazine and propoxyphen. Other drugs made from propiophenone include the following: PDM-35, Eprazinone, Methcathinone (leading to ephedrine), Tri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N-propylbenzene
''n''-Propylbenzene is an aromatic hydrocarbon with the formula . The molecule consists of a propyl group attached to a phenyl ring. It is a colorless liquid. A more common structural isomer of this compound is cumene. ''n''-Propylbenzene is used as a nonpolar organic solvent in various industries, including printing and the dyeing of textiles and in the manufacture of methylstyrene. It can be synthesized by the reaction of the Grignard reagent derived from benzyl chloride Benzyl chloride, or α-chlorotoluene, is an organic compound with the formula . This colorless liquid is a reactive organochlorine compound that is a widely used chemical building block. Preparation Benzyl chloride is prepared industrially ... with diethyl sulfate. References {{DEFAULTSORT:Propylbenzene, n- Alkylbenzenes C3-Benzenes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
