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The Claisen rearrangement is a powerful carbon-carbon bond-forming chemical reaction discovered by Rainer Ludwig Claisen. The heating of an allyl vinyl ether will initiate a [3,3]-sigmatropic rearrangement to give a γ,δ-unsaturated carbonyl. General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Atomic mass 12. ...
A chemical bond is the physical process responsible for the attractive interactions between atoms and molecules, and that which confers stability to diatomic and polyatomic chemical compounds. ...
A chemical reaction occurs when vapours of hydrogen chloride in a beaker and ammonia in a test tube meet to form a cloud of a new substance, ammonium chloride A chemical reaction is a process that results in the interconversion of chemical substances. ...
Rainer Ludwig Claisen (January 14, 1851 - January 5, 1930) was a famous German chemist best known for his work with condensations of carbonyls and sigmatropic rearrangements. ...
An allyl group is an alkene hydrocarbon group with the formula H2C=CH-CH2-. It is made up of a vinyl group, CH2=CH-, attached to a methylene -CH2. ...
Chemical structure of the vinyl functional group. ...
Ether is the general name for a class of chemical compounds which contain an ether group — an oxygen atom connected to two (substituted) alkyl groups. ...
A Sigmatropic reaction is a pericyclic reaction where the net result is one sigma bond being changed to another sigma bond. ...
Discovered in 1912, the Claisen rearrangement is the first recorded example of a [3,3]-sigmatropic rearrangement. Image File history File links Download high resolution version (828x292, 2 KB) Description: Chemical scheme of the Claisen rearrangement. ...
1912 (MCMXII) was a leap year starting on Monday in the Gregorian calendar (or a leap year starting on Tuesday in the 13-day-slower Julian calendar). ...
- Claisen, L.; Ber. 1912, 45, 3157.
- Claisen, L.; Tietze, E.; Ber. 1925, 58, 275.
- Claisen, L.; Tietze, E.; Ber. 1926, 59, 2344.
Chemische Berichte (usually abbreviated as or ) is a German-language scientific journal featuring chemistry of all disciplines. ...
Chemische Berichte (usually abbreviated as or ) is a German-language scientific journal featuring chemistry of all disciplines. ...
Chemische Berichte (usually abbreviated as or ) is a German-language scientific journal featuring chemistry of all disciplines. ...
Mechanism The Claisen rearrangement (and its variants) are exothermic (about 84 kJ/mol), concerted pericyclic reactions which according to the Woodward-Hoffmann rules show a suprafacial reaction pathway. In thermodynamics, the word exothermic describes a process or reaction that releases energy in the form of heat. ...
In organic chemistry, a pericyclic reaction is a type of reaction where the transition state of molecule has a cyclic geometry, and the reaction progresses in a concerted reactions fashion. ...
The Woodward-Hoffmann rules devised by Robert Burns Woodward and Roald Hoffmann are a set of rules in organic chemistry predicting the stereochemistry of pericyclic reactions based on orbital symmetry. ...
There are substantial solvent effects in the Claisen reactions. More polar solvents tend to accelerate the reaction to a greater extent. Hydrogen-bonding solvents gave the highest rate constants. For example, ethanol/water solvent mixtures give rate constants 10-fold higher than sulfolane.[1][2] For other uses, see Solvent (disambiguation). ...
Ethanol, also known as ethyl alcohol, drinking alcohol or grain alcohol, is a flammable, colorless, slightly toxic chemical compound with a distinctive perfume-like odor, and is the alcohol found in alcoholic beverages. ...
Impact of a drop of water. ...
Sulfolane (systematic name: 2,3,4,5-tetrahydrothiophene-1,1-dioxide) is a clear, colorless liquid commonly used in the chemical industry as an extractive distillation solvent or reaction solvent. ...
Trivalent organoaluminum reagents, such as trimethylaluminum, have been shown to accelerate this reaction. Aluminum is a soft and lightweight metal with a dull silvery appearance, due to a thin layer of oxidation that forms quickly when it is exposed to air. ...
Trimethylaluminium is the chemical compound with the formula Al2(CH3)6, abbreviated as Al2Me6, (AlMe3)2 or the misnomer TMA. This pyrophoric, colorless liquid is an industrially important organoaluminium compound. ...
- Goering, H. L.; Jacobson, R. R.; J. Am. Chem. Soc. 1958, 80, 3277.
- White, W. N.; Wolfarth, E. F.; J. Org. Chem. 1970, 35, 2196.
The Journal of the American Chemical Society (usually abbreviated as , or JACS), is a peer-reviewed scientific journal, published since 1879 by the American Chemical Society. ...
The Journal of Organic Chemistry (abbreviated as ) is a scientific journal for original contributions of fundamental research in organic and bioorganic chemistry. ...
Variations
Aromatic Claisen rearrangement The aromatic variation of the Claisen rearrangement is the [3,3]-sigmatropic rearrangement of an allyl phenyl ether to an intermediate which quickly tautomerizes to an ortho-substituted phenol. A Sigmatropic reaction is a pericyclic reaction where the net result is one sigma bond being changed to another sigma bond. ...
An allyl group is an alkene hydrocarbon group with the formula H2C=CH-CH2-. It is made up of a vinyl group, CH2=CH-, attached to a methylene -CH2. ...
In chemistry, the phenyl group or phenyl ring (often abbreviated as -Ph) is the functional group with the formula -C6H5 Picture where the six carbon atoms are arranged in a cyclic manner. ...
Ether is the general name for a class of chemical compounds which contain an ether group — an oxygen atom connected to two (substituted) alkyl groups. ...
Phenol, also known under an older name of carbolic acid, is a colourless crystalline solid with a typical sweet tarry odor. ...
Image:Aromatic Claisen Retreacftyu Scheme.png
Bellus-Claisen rearrangement The Bellus-Claisen rearrangement is the reaction of allylic ethers, amines, and thioethers with ketenes to give γ,δ-unsaturated esters, amides, and thioesters. - Malherbe, R.; Bellus, D.; Helv. Chim. Acta 1978, 61, 3096-3099.
- Malherbe, R.; Rist, G.; Bellus, D.; J. Org. Chem. 1983, 48, 860-869.
- Gonda, J.; Angew. Chem. Int. Ed. 2004, 43, 3516-3524.
Image File history File links Claisen_Bellus_Rearrangement. ...
The Journal of Organic Chemistry (abbreviated as ) is a scientific journal for original contributions of fundamental research in organic and bioorganic chemistry. ...
Angewandte Chemie or Angewandte Chemie International Edition is the chemistry journal of the Gesellschaft Deutscher Chemiker (Society of German Chemists). ...
Eschenmoser-Claisen rearrangement The Eschenmoser-Claisen rearrangement proceeds from an allylic alcohol to a γ,δ-unsaturated amide, and was developed by Albert Eschenmoser in 1964. 1964 (MCMLXIV) was a leap year starting on Wednesday (the link is to a full 1964 calendar). ...
- Wick, A. E.; Felix, D.; Steen, K.; Eschenmoser, A.; Helv. Chim. Acta 1964, 47, 2425-2429.
- Wick, A. E.; Felix, D.; Gschwend-Steen, K.; Eschenmoser, A.; Helv. Chim. Acta 1969, 52, 1030-1042.
Image File history File links Download high resolution version (1669x408, 6 KB) Description: Chemical structure of Eschenmoser-Claisen rearrangement. ...
Ireland-Claisen rearrangement The Ireland-Claisen rearrangement is the reaction of an allylic acetate with strong base (such as butyl lithium) to give a γ,δ-unsaturated carboxylic acid. An allyl group is an alkene hydrocarbon group with the formula H2C=CH-CH2-. It is made up of a vinyl group, CH2=CH-, attached to a methylene -CH2. ...
Acetate, or ethanoate, is the anion of a salt or ester of acetic acid. ...
An organolithium reagent is a carbon nucleophile similar to a Grignard reagent. ...
Structure of a carboxylic acid The 3D structure of the carboxyl group A space-filling model of the carboxyl group Carboxylic acids are organic acids characterized by the presence of a carboxyl group, which has the formula -C(=O)OH, usually written -COOH or -CO2H. [1] Carboxylic acids are Bronsted...
Image File history File links Download high resolution version (1676x352, 5 KB) File links The following pages link to this file: Claisen rearrangement ...
The Journal of the American Chemical Society (usually abbreviated as , or JACS), is a peer-reviewed scientific journal, published since 1879 by the American Chemical Society. ...
Tetrahedron Letters is a weekly international journal for rapid publication of full origonal research papers in the field of organic chemistry. ...
Johnson-Claisen rearrangement The Johnson-Claisen rearrangement is the reaction of an allylic alcohol with trimethyl orthoacetate to give a γ,δ-unsaturated ester. An allyl group is an alkene hydrocarbon group with the formula H2C=CH-CH2-. It is made up of a vinyl group, CH2=CH-, attached to a methylene -CH2. ...
Functional group of an alcohol molecule. ...
General formula of a carboxylate ester. ...
Image File history File links Download high resolution version (1757x374, 6 KB) Description: Chemical structure of Johnson-Claisen rearrangement. ...
The Journal of the American Chemical Society (usually abbreviated as , or JACS), is a peer-reviewed scientific journal, published since 1879 by the American Chemical Society. ...
Hetero-Claisens
Aza-Claisen - Kurth, M. J.; Decker, O. H. W.; J. Org. Chem. 1985, 50, 5769-5775.
Image File history File links Download high resolution version (2107x491, 10 KB) Summary Description: Example reaction scheme of the Aza-Claisen rearrangement. ...
The Journal of Organic Chemistry (abbreviated as ) is a scientific journal for original contributions of fundamental research in organic and bioorganic chemistry. ...
Chromium Oxidation Chromium can oxidize allylic alcohols to alpha-beta unsaturated ketones on the opposite side of the unsaturated bond from the alcohol. This is via a concerted hetero-claisen reaction, although there are mechanistic differences since the chromium atom has access to d- shell orbitals which allow the reaction under a less constrained set of geometries. Image File history File links Claisen-based chromium oxidation of allylic alcohols File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...
The Journal of Organic Chemistry (abbreviated as ) is a scientific journal for original contributions of fundamental research in organic and bioorganic chemistry. ...
Organic Syntheses is a scientific journal that Since 1921 has provided the chemistry community with annual collections of detailed and checked procedures for the organic synthesis of organic compounds. ...
Chen-Mapp Reaction The Chen-Mapp reaction also known as the [3,3]-Phosphorimidate Rearrangement or Staudinger-Claisen Reaction installs a phosphite in the place of an alcohol and takes advantage of the Staudinger Ligation to convert this to an imine. The subsequent claisen is driven by the fact that a P=O double bond is more energetically favorable than a P=N double bond. The Staudinger ligation (also called the Staudinger reaction) is a chemical reaction in which the combination of an azide with a phosphine or phosphite produces a phosphorimidate. ...
Image File history File links Mapp Reaction? (Still unnamed) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...
The Journal of the American Chemical Society (usually abbreviated as , or JACS), is a peer-reviewed scientific journal, published since 1879 by the American Chemical Society. ...
The Overman rearrangement (named after Larry Overman) is a Claisen rearrangement of allylic trichloroacetimidates to allylic trichloroacetamides. The Overman rearrangement is a chemical reaction that can be described as a Claisen rearrangement of allylic trichloroacetimidates to give allylic trichloroacetamides. ...
The Overman rearrangement is a chemical reaction that can be described as a Claisen rearrangement of allylic trichloroacetimidates to give allylic trichloroacetamides. ...
- Overman, L. E. J. Am. Chem. Soc. 1974, 96, 597.
- Overman, L. E. J. Am. Chem. Soc. 1976, 98, 2901.
- Overman, L. E. Accts. Chem. Res. 1980, 13, 218-224.
- Organic Syntheses, Coll. Vol. 6, p.507; Vol. 58, p.4 (Article)
Image File history File links Download high resolution version (1702x313, 5 KB) Summary Description: Reaction scheme of the Overman reaction. ...
The Journal of the American Chemical Society (usually abbreviated as , or JACS), is a peer-reviewed scientific journal, published since 1879 by the American Chemical Society. ...
The Journal of the American Chemical Society (usually abbreviated as , or JACS), is a peer-reviewed scientific journal, published since 1879 by the American Chemical Society. ...
Accounts of Chemical Research (usually abbreviated as ) is a peer-reviewed scientific journal, published since 1968 by the American Chemical Society. ...
Organic Syntheses is a scientific journal that Since 1921 has provided the chemistry community with annual collections of detailed and checked procedures for the organic synthesis of organic compounds. ...
Thio-Claisen
Claisen rearrangement in nature The enzyme Chorismate mutase (EC 5.4.99.5) catalyzes the Claisen rearrangement of chorismate ion to prephenate ion, a key intermediate in the shikimic acid pathway (the biosynthetic pathway towards the synthesis of phenylalanine and tyrosine). Chorismic acid, more commonly known as its anionic form chorismate, is an important biochemical intermediate in plants and microorganisms. ...
Prephenic acid, more commonly known by its anionic form prephenate, is an intermediate in the biosynthesis of the aromatic amino acids phenylalanine and tyrosine. ...
Shikimic acid, more commonly known as its anionic form shikimate, is an important biochemical intermediate in plants and microorganisms. ...
Biosynthesis is a phenomenon where chemical compounds are produced from simpler reagents. ...
Phe redirects here. ...
Tyrosine (from the Greek tyros, meaning cheese, as it was first discovered in 1846 by German chemist Justus von Liebig in cheese[1][2]), 4-hydroxyphenylalanine, or 2-amino-3(4-hydroxyphenyl)-propanoic acid, is one of the 20 amino acids that are used by cells to synthesize proteins. ...
Image File history File links Download high resolution version (1334x489, 8 KB) Summary Description: Chemical reaction scheme of Chorismate mutase. ...
Angewandte Chemie or Angewandte Chemie International Edition is the chemistry journal of the Gesellschaft Deutscher Chemiker (Society of German Chemists). ...
General References - Rhoads, S. J.; Raulins, N. R.; Org. React. 1975, 22, 1-252.
- Ziegler, F. E.; Chem. Rev. 1988, 88, 1423-1452.
- Wipf, P.; Comp. Org. Syn. 1991, 5, 827-873.
Chemical Reviews (usually abbreviated as ), is a peer-reviewed scientific journal, published since 1900 by the American Chemical Society. ...
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