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Citraconic Acid
Citraconic acid is an organic compound with the formula CH3C2H(CO2H)2. It is a white solid. It is the ''cis''- isomer of mesaconic acid. It is one of the pyrocitric acids formed upon the heating of citric acid. Citraconic acid can be produced, albeit inefficiently, by oxidation of xylene and methylbutanols. The acid displays the unusual property of spontaneously forming the anhydride, which, unlike maleic anhydride, is a liquid at room temperature. In the laboratory, citraconic acid can be produced by thermal isomerization of itaconic acid anhydride to give citraconic anhydride, which can be hydrolyzed to citraconic acid. The required itaconic acid anhydride is obtained by dry distillation of citric acid Citric acid is an organic compound with the chemical formula HOC(CO2H)(CH2CO2H)2. It is a colorless weak organic acid. It occurs naturally in citrus fruits. In biochemistry, it is an intermediate in the citric acid cycle, which occurs in .... References Dicarbox ... [...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. Liv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isomer
In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers. Isomers do not necessarily share similar chemical or physical properties. Two main forms of isomerism are structural or constitutional isomerism, in which ''bonds'' between the atoms differ; and stereoisomerism or spatial isomerism, in which the bonds are the same but the ''relative positions'' of the atoms differ. Isomeric relationships form a hierarchy. Two chemicals might be the same constitutional isomer, but upon deeper analysis be stereoisomers of each other. Two molecules that are the same stereoisomer as each other might be in different conformational forms or be different isotopologues. The depth of analysis depends on the field of study or the chemical and physical properties of interest. The English word "isomer" () is a back ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesaconic Acid
Mesaconic acid is one of several isomeric carboxylic acids obtained from citric acid. It is a colorless solid. Synthesis and reactions It is prepared from citric acid, which is first converted to itaconic anhydride by dehydration and decarboxylation. Itaconic acid anhydride is isomerized to citraconic anhydride, which is hydrolyzed and the resulting acid further isomerized under acid-catalysis to give mesaconic acid. Hydration of mesaconic acid, a conversion catalyzed by mesaconyl-C4-CoA hydratase, gives citramalic acid. History This acid was studied for the first time by Jacobus H. van 't Hoff in 1874. It was later shown to be produced by ''Clostridium tetanomorphum''. Further studies showed that this organic compound is involved in the biosynthesis of vitamin B12. It is a competitive inhibitor of fumarate reduction. The compound has been considered as a renewable precursor to the commodity chemical methacrylic acid Methacrylic acid, abbreviated MAA, is an organic com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrocitric Acid
Pyrocitric is a group of organic chemical compounds pertaining to, or designating, any one of three acids obtained by the distillation of citric acid, and called respectively citraconic, itaconic, and mesaconic acid Mesaconic acid is one of several isomeric carboxylic acids obtained from citric acid. It is a colorless solid. Synthesis and reactions It is prepared from citric acid, which is first converted to itaconic anhydride by dehydration and decarboxy .... References External links * Citric acid cycle compounds {{organic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Citric Acid
Citric acid is an organic compound with the chemical formula HOC(CO2H)(CH2CO2H)2. It is a colorless weak organic acid. It occurs naturally in citrus fruits. In biochemistry, it is an intermediate in the citric acid cycle, which occurs in the metabolism of all aerobic organisms. More than two million tons of citric acid are manufactured every year. It is used widely as an acidifier, as a flavoring, and a chelating agent. A citrate is a derivative of citric acid; that is, the salts, esters, and the polyatomic anion found in solution. An example of the former, a salt is trisodium citrate; an ester is triethyl citrate. When part of a salt, the formula of the citrate anion is written as or . Natural occurrence and industrial production Citric acid occurs in a variety of fruits and vegetables, most notably citrus fruits. Lemons and limes have particularly high concentrations of the acid; it can constitute as much as 8% of the dry weight of these fruits (about 47 g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maleic Anhydride
Maleic anhydride is an organic compound with the formula C2H2(CO)2O. It is the acid anhydride of maleic acid. It is a colorless or white solid with an acrid odor. It is produced industrially on a large scale for applications in coatings and polymers. Production Maleic anhydride is produced by vapor-phase oxidation of ''n''-butane. The overall process converts the methyl groups to carboxylate and dehydrogenates the backbone. The selectivity of the process reflects the robustness of maleic anhydride, with its conjugated double-bond system. Traditionally maleic anhydride was produced by the oxidation of benzene or other aromatic compounds. As of 2006, only a few smaller plants continue to use benzene. In both cases, benzene and butane are fed into a stream of hot air, and the mixture is passed through a catalyst bed at high temperature. The ratio of air to hydrocarbon is controlled to prevent the mixture from igniting. Vanadium pentoxide and molybdenum trioxide are the catalys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Itaconic Acid
Itaconic acid, or methylidenesuccinic acid, is an organic compound. This dicarboxylic acid is a white solid that is soluble in water, ethanol, and acetone. Historically, itaconic acid was obtained by the distillation of citric acid, but currently it is produced by fermentation. The name ''itaconic acid'' was devised as an anagram of aconitic acid, another derivative of citric acid. Production Since the 1960s, it is produced industrially by the fermentation of carbohydrates such as glucose or molasses using fungi such as '' Aspergillus itaconicus'' or ''Aspergillus terreus''. For ''A. terreus'' the itaconate pathway is mostly elucidated. The generally accepted route for itaconate is via glycolysis, tricarboxylic acid cycle, and a decarboxylation of ''cis''-aconitate to itaconate via ''cis''-aconitate-decarboxylase. The smut fungus ''Ustilago maydis'' uses an alternative route. ''Cis''-aconitate is converted to the thermodynamically favoured ''trans''-aconitate via aconita ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
