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Nitrolic Acid
Nitrolic acids are organic compounds with the functional group RC(NO2)=NOH. They are prepared by the reaction of nitroalkanes with base and nitrite sources: :RCH2NO2 + HNO2 → RC(NO2)=NOH + H2O The conversion was first demonstrated by Victor Meyer using nitroethane.Meyer, V.; Locher, J. "Untersuchungen über die Constitution der Nitrolsäuren (Researches on the constitution of the nitrolic acids)" Deut. Chem. Ges. Ber., 1874, volume 7, pp. 670-5. The reaction proceeds via the intermediacy of the nitronate anion. Occurrence Most nitrolic acids are laboratory curiosities. One exception is the compound HO2C(CH2)4C(NO2)=NOH, which is produced by the oxidation of cyclohexanone with nitric acid. This species decomposes to adipic acid and nitrous oxide: :HO2C(CH2)4C(NO2)=NOH → HO2C(CH2)4CO2H + N2O This conversion is thought to be the largest anthropogenic route to N2O, which, on a molecule-to-molecule basis, has 298 times the atmospheric heat-trapping abilit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. 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, hydrogen cyanide), are not classified as organic compounds and are considered inorganic. Other than those just named, little consensus exists among chemists on precisely which carbon-containing compounds are excluded, making any rigorous definition of an organic compound elusive. Although organic compounds make up only a small percentage of Earth's crust, they are of central importance because all known life is based on organic compounds. Living t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Functional Group
In organic chemistry, a functional group is a substituent or moiety in a molecule that causes the molecule's characteristic chemical reactions. The same functional group will undergo the same or similar chemical reactions regardless of the rest of the molecule's composition. This enables systematic prediction of chemical reactions and behavior of chemical compounds and the design of chemical synthesis. The reactivity of a functional group can be modified by other functional groups nearby. Functional group interconversion can be used in retrosynthetic analysis to plan organic synthesis. A functional group is a group of atoms in a molecule with distinctive chemical properties, regardless of the other atoms in the molecule. The atoms in a functional group are linked to each other and to the rest of the molecule by covalent bonds. For repeating units of polymers, functional groups attach to their nonpolar core of carbon atoms and thus add chemical character to carbon chains. Fun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitroalkane
In organic chemistry, nitro compounds are organic compounds that contain one or more nitro functional groups (). The nitro group is one of the most common explosophores (functional group that makes a compound explosive) used globally. The nitro group is also strongly electron-withdrawing. Because of this property, bonds alpha (adjacent) to the nitro group can be acidic. For similar reasons, the presence of nitro groups in aromatic compounds retards electrophilic aromatic substitution but facilitates nucleophilic aromatic substitution. Nitro groups are rarely found in nature. They are almost invariably produced by nitration reactions starting with nitric acid. Synthesis Preparation of aromatic nitro compounds Aromatic nitro compounds are typically synthesized by nitration. Nitration is achieved using a mixture of nitric acid and sulfuric acid, which produce the nitronium ion (), which is the electrophile: + The nitration product produced on the l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Victor Meyer
Viktor Meyer (8 September 18488 August 1897) was a German chemist and significant contributor to both organic and inorganic chemistry. He is best known for inventing an apparatus for determining vapour densities, the Viktor Meyer apparatus, and for discovering thiophene, a heterocyclic compound. He is sometimes referred to as Victor Meyer, a name used in some of his publications. Early life Viktor Meyer was born in Berlin in 1848, the son of trader and cotton printer Jacques Meyer and mother, Bertha. His parents were Jewish, though he was not actively raised in the Jewish faith. Later, he was confirmed in a Reform Jewish congregation. He married a Christian woman, Hedwig Davidson, and raised his children as such. He entered the gymnasium at the age of ten in the same class as his two-year older brother Richard. Although he had excellent science skills his wish to become an actor was based on his love for poetry. At a visit from his brother Richard, who was studying chemistry at t ... [...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] |
Nitronate
A nitronate (IUPAC: azinate) in organic chemistry is a functional group with the general structure . It is the anion of nitronic acid (sometimes also called an aci, or an azinic acid), a tautomeric form of a nitro compound. Just as ketones and aldehydes can exist in equilibrium with their enol tautomer, nitro compounds exist in equilibrium with their nitronate tautomer under basic conditions. In practice they are formed by the deprotonation of the α-carbon, the pka of which is typically around 17. : Nitronates are formed as intermediates in the Henry reaction and Nef reaction In organic chemistry, the Nef reaction is an organic reaction describing the acid hydrolysis of a salt of a primary or secondary nitroalkane () to an aldehyde () or a ketone () and nitrous oxide (). The reaction has been the subject of sever ..., the latter of which also demonstrates the instability of the nitronic acid form. The nitronate has two different resonance structures, one with a negative ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclohexanone
Cyclohexanone is the organic compound with the formula (CH2)5CO. The molecule consists of six-carbon cyclic molecule with a ketone functional group. This colorless oily liquid has an odor reminiscent of acetone. Over time, samples of cyclohexanone assume a pale yellow color. Cyclohexanone is slightly soluble in water and miscible with common organic solvents. Billions of kilograms are produced annually, mainly as a precursor to nylon. Production Cyclohexanone is produced by the oxidation of cyclohexane in air, typically using cobalt catalysts: :C6H12 + O2 → (CH2)5CO + H2O This process forms cyclohexanol as a by-product, and this mixture, called "KA Oil" for ketone-alcohol oil, is the main feedstock for the production of adipic acid. The oxidation involves radicals and the hydroperoxide C6H11O2H as an intermediate. In some cases, purified cyclohexanol, obtained by hydration of cyclohexene, is the precursor. Alternatively, cyclohexanone can be produced by the partial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitric Acid
Nitric acid is the inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but older samples tend to be yellow cast due to decomposition into oxides of nitrogen. Most commercially available nitric acid has a concentration of 68% in water. When the solution contains more than 86% , it is referred to as ''fuming nitric acid''. Depending on the amount of nitrogen dioxide present, fuming nitric acid is further characterized as red fuming nitric acid at concentrations above 86%, or white fuming nitric acid at concentrations above 95%. Nitric acid is the primary reagent used for nitration – the addition of a nitro group, typically to an organic molecule. While some resulting nitro compounds are shock- and thermally-sensitive explosives, a few are stable enough to be used in munitions and demolition, while others are still more stable and used as pigments in inks and dyes. Nitric acid is also commonly used as a strong oxidizing agen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adipic Acid
Adipic acid or hexanedioic acid is the organic compound with the formula (CH2)4(COOH)2. From an industrial perspective, it is the most important dicarboxylic acid: about 2.5 billion kilograms of this white crystalline powder are produced annually, mainly as a precursor for the production of nylon. Adipic acid otherwise rarely occurs in nature, but it is known as manufactured E number food additive E355. Preparation and reactivity Adipic acid is produced from a mixture of cyclohexanone and cyclohexanol called KA oil, the abbreviation of ketone-alcohol oil. The KA oil is oxidized with nitric acid to give adipic acid, via a multistep pathway. Early in the reaction, the cyclohexanol is converted to the ketone, releasing nitrous acid: :HOC6H11 + HNO3 → OC(CH2)5 + HNO2 + H2O Among its many reactions, the cyclohexanone is nitrosated, setting the stage for the scission of the C-C bond: :HNO2 + HNO3 → NO+NO3− + H2O :OC6H10 + NO+ → OC6H9-2-NO + H+ Side products of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrous Oxide
Nitrous oxide (dinitrogen oxide or dinitrogen monoxide), commonly known as laughing gas, nitrous, or nos, is a chemical compound, an oxide of nitrogen with the formula . At room temperature, it is a colourless non-flammable gas, and has a slightly sweet scent and taste. At elevated temperatures, nitrous oxide is a powerful oxidiser similar to molecular oxygen. Nitrous oxide has significant medical uses, especially in surgery and dentistry, for its anaesthetic and pain-reducing effects. Its colloquial name, "laughing gas", coined by Humphry Davy, is due to the euphoric effects upon inhaling it, a property that has led to its recreational use as a dissociative anaesthetic. It is on the World Health Organization's List of Essential Medicines. It is also used as an oxidiser in rocket propellants, and in motor racing to increase the power output of engines. Nitrous oxide's atmospheric concentration reached 333 parts per billion (ppb) in 2020, increasing at a rate of abo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nylon
Nylon is a generic designation for a family of synthetic polymers composed of polyamides ( repeating units linked by amide links).The polyamides may be aliphatic or semi-aromatic. Nylon is a silk-like thermoplastic, generally made from petroleum, that can be melt-processed into fibers, films, or shapes. Nylon polymers can be mixed with a wide variety of additives to achieve many property variations. Nylon polymers have found significant commercial applications in fabric and fibers (apparel, flooring and rubber reinforcement), in shapes (molded parts for cars, electrical equipment, etc.), and in films (mostly for food packaging). History DuPont and the invention of nylon Researchers at DuPont began developing cellulose based fibers, culminating in the synthetic fiber rayon. DuPont's experience with rayon was an important precursor to its development and marketing of nylon. DuPont's invention of nylon spanned an eleven-year period, ranging from the initial research pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
