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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 ,3sigmatropic 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 decompo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Reaction
A chemical reaction is a process that leads to the IUPAC nomenclature for organic transformations, chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the Atomic nucleus, nuclei (no change to the elements present), and can often be described by a chemical equation. Nuclear chemistry is a sub-discipline of chemistry that involves the chemical reactions of unstable and radioactive Chemical element, elements where both electronic and nuclear changes can occur. The substance (or substances) initially involved in a chemical reaction are called reagent, reactants or reagents. Chemical reactions are usually characterized by a chemical change, and they yield one or more Product (chemistry), products, which usually have properties different from the reactants. Reactions often consist of a sequence o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dichloromethane
Dichloromethane (DCM or methylene chloride, methylene bichloride) is an organochlorine compound with the formula . This colorless, volatile liquid with a chloroform-like, sweet odour 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 1993. ... [...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. 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 chloroethane, bromo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ephedrine
Ephedrine is a central nervous system (CNS) stimulant that is often used to prevent 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 by mouth or by injection into a muscle, vein, or just under the skin. Onset with intravenous use is fast, while injection into a muscle can take 20 minutes, 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 trouble sleeping, anxiety, headache, hallucinations, high blood pressure, fast heart rate, loss of appetite, and inability to urinate. Serious side effects include stroke and heart attack. While likely safe in pregnancy, its use in this population is poorly studied. Use during breastfeeding is not recommended. Ephedrine works by increasing the activity of the α and β adrenergic ... [...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 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, this is formally an addition reaction rather than a condensation reaction because it does not invo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Dichromate
Potassium dichromate, , is a common inorganic chemical reagent, most commonly used as an oxidizing agent in various laboratory and industrial applications. As with all hexavalent chromium compounds, it is acutely and chronically harmful to health. It is a crystalline ionic solid with a very bright, red-orange color. The salt is popular in the laboratory 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. Chemistry Production Potassium dichromate is usually prepared by the reaction of potassium chloride on sodium dichromate. Alternatively, it can be also obtained from potassium chromate by roasting chromite ore with potassium hydroxide. It is soluble in water and in the dissolution process it io ... [...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, that dissolves in water as K+ and , 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 on the World Health Organization's List of Essential Medicines. In 2000, worldwide production was estimated at 30,000 tonnes. Properties Potassium permanganate is the potassium salt of the tetrahedral transition metal oxo complex permanganate, in which four O2- ligands are bound to a manganese(VII) center. Structure KMnO4 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 solutions. In the solid (as in solution), each MnO4− centre is t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1-Tetralone
1-Tetralone is a bicyclic aromatic hydrocarbon and a ketone. In terms of its structure, it can also be regarded as benzo-fused cyclohexanone. It is a colorless oil with a faint odor. It is used as starting material for agricultural and pharmaceutical agents. The carbon skeleton of 1-tetralone is found in natural products such as Aristelegone A (4,7-dimethyl-6-methoxy-1-tetralone) from the family of Aristolochiaceae used in traditional Chinese medicine. Preparation By oxidation of 1,2,3,4-tetrahydronaphthalene As already described in 1933 by Heinrich Hock, 1,2,3,4-tetrahydronaphthalene tends to autoxidize and gradually forms the 1-hydroperoxide with atmospheric oxygen. The heavy metal ion catalyzed air oxidation of 1,2,3,4-tetrahydronaphthalene with Cr3+ or Cu2+ in the liquid phase leads via the hydroperoxide to a mixture of the intermediate 1-tetralol and the final product 1-tetralone. The boiling points of the main component 1-tetralone (255-257 °C) and the min ... [...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 is an organic compound with the chemical formula C6H5CH2COCH3. It is a colorless oil that is soluble in organic solvents. This substance is used in the manufacture of methamphetamine and amphetamine, where it is commonly known as P2P. Due to the illicit uses in clandestine chemistry, it 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 One method of creating phenylacetone is via: : phenylacetic acid (C8H8O2) + acetic anhydride (C4H6O3) + pyridine catalyst → phenylacetone (C9H10O) + carbon dioxide (CO2) + water (H2O) Sodium acetate has been used instead of pyridine. In the 20th century chloroacetone, benzene, and anhydrous aluminum chloride were used to synthesize phenylacetone.https://pubs.acs.org/doi/10.1021/ja01863a506 62, 6, 1622. https://doi.org/10.1021/ja01863a506 The reaction includ ... [...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 Calcium acetate is a chemical compound which is a calcium salt of acetic acid. It has the formula Ca(C2H3O2)2. Its standard name is calcium acetate, while calcium ethanoate is the systematic name. An older name is acetate of lime. The anhydrous ... and alumina at 450–550 °C: :C6H5CO2H + CH3CH2CO2H → C6H5C(O)CH2CH3 + CO2 + H2O Ludwig Claisen discovered that α-methoxystyrene forms this compound when heated for an hour at 300 °C (65% yield). Uses 120px, left, Phenmetrazine, derived from propiophenone, is an appetite suppressant."> ... [...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 with diethyl sulfate Diethyl sulfate (DES) is a highly toxic, combustible, and likely carcinogenic chemical compound with the formula (C2H5)2SO4. It occurs as a colorless, oily liquid with a faint peppermint odor and is corrosive to tissue and metals. Diethyl sulfate .... References {{DEFAULTSORT:Propylbenzene, n- Alkylbenzenes C3-Benzenes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
