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3-Methyl-3-penten-2-one
3-Methyl-3-penten-2-one is an unsaturated aliphatic ketone. It is an isomer of mesityl oxide and isomesityl oxide. It is a precursor of 3-methyl-2-pentanone (methyl ''sec''-butyl ketone) and is obtained by acid-catalyzed dehydration In physiology, dehydration is a lack of total body water, with an accompanying disruption of metabolic processes. It occurs when free water loss exceeds free water intake, usually due to exercise, disease, or high environmental temperature. Mi ... of 4-hydroxy-3-methyl-2-pentanone. It is used as an intermediate in organic chemistry syntheses. : References Enones {{ketone-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ketone
In organic chemistry, a ketone is a functional group with the structure R–C(=O)–R', where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group –C(=O)– (which contains a carbon-oxygen double bond C=O). The simplest ketone is acetone (where R and R' is methyl), with the formula . Many ketones are of great importance in biology and in industry. Examples include many sugars (ketoses), many steroids (e.g., testosterone), and the solvent acetone. Nomenclature and etymology The word ''ketone'' is derived from ''Aketon'', an old German word for ''acetone''. According to the rules of IUPAC nomenclature, ketone names are derived by changing the suffix ''-ane'' of the parent alkane to ''-anone''. Typically, the position of the carbonyl group is denoted by a number, but traditional nonsystematic names are still generally used for the most important ketones, for example acetone and benzophenone. These nonsystematic names are considered reta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesityl Oxide
Mesityl oxide is a α,β-unsaturated ketone with the formula CH3C(O)CH=C(CH3)2. This compound is a colorless, volatile liquid with a honey-like odor. Synthesis It is prepared by the aldol condensation of acetone to give diacetone alcohol, which readily dehydrates to give this compound. : Phorone and isophorone may be formed under the same conditions. Isophorone originates via a Michael addition: : Phorone is formed by continued aldol condensation: : Uses Mesityl oxide is used as a solvent and in the production of methyl isobutyl ketone by hydrogenation: : Further hydrogenation gives 4-methyl-2-pentanol (methyl isobutyl carbinol). Dimedone Dimedone is a cyclic diketone used in organic chemistry to determine whether a compound contains an aldehyde group. Cyclohexanediones in general can be used as catalysts in the formation of transition-metal complexes. Other uses include applica ... is another established use of mesityl oxide. References {{reflist External links ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3-Methyl-2-pentanone
3-Methyl-2-pentanone (methyl ''sec''-butyl ketone) is an aliphatic ketone and isomer of 2-hexanone. It is used as a solvent and as an intermediate for syntheses. Its industrial importance is low. It is produced by base-catalyzed aldol condensation of 2-butanone with acetaldehyde, forming 4-hydroxy-3-methyl-2-pentanone, which is dehydrated to 3-methyl-3-penten-2-one over an acid catalyst, followed by hydrogenation Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate org ... over a palladium catalyst. : References {{DEFAULTSORT:Methyl-2-pentanone, 3- Ketone solvents Hexanones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehydration Reaction
In chemistry, a dehydration reaction is a chemical reaction that involves the loss of water from the reacting molecule or ion. Dehydration reactions are common processes, the reverse of a hydration reaction. Dehydration reactions in organic chemistry Esterification The classic example of a dehydration reaction is the Fischer esterification, which involves treating a carboxylic acid with an alcohol to give an ester :RCO2H + R′OH RCO2R′ + H2O Often such reactions require the presence of a dehydrating agent, i.e. a substance that reacts with water. Etherification Two monosaccharides, such as glucose and fructose, can be joined together (to form saccharose) using dehydration synthesis. The new molecule, consisting of two monosaccharides, is called a disaccharide. Nitrile formation Nitriles are often prepared by dehydration of primary amides. :RC(O)NH2 → RCN + H2O Ketene formation Ketene is produced by heating acetic acid and trapping the product: :CH3CO2H → CH2= ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ullmann's Encyclopedia Of Industrial Chemistry
''Ullmann's Encyclopedia of Industrial Chemistry'' is a major reference work related to industrial chemistry by Chemist Fritz Ullmann, first published in 1914, and exclusively in German as "Enzyklopädie der Technischen Chemie" until 1984. History Ullmann's Encyclopedia of Industrial Chemistry is a major reference work related to industrial chemistry by chemist Fritz Ullmann. Its 1st edition was published in German by Fritz Ullmann in 1914. The 4th edition, published 1972 to 1984, already contained 25 volumes. The 5th edition, published 1985 to 1996, was the first version available in English. In 1997, the first online version was published. 2014 marked its centenary. As of 2016, Ullmann's Encyclopedia was in its 7th edition, in 40 volumes including one index volume and more than 1,050 articles (200 more than the 6th edition), approx. 30,000 pages, 22,000 images, 8,000 tables, 19,000 references and 85,000 indices. Editions * 1914–1922: 1st edition in 12 volumes, whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
