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Encyclopedia > Acyloin
The structure of a typical acyloin.
The structure of a typical acyloin.

Acyloins are a class of organic compounds in organic chemistry sharing a common functional group consisting of a hydroxyl group placed on the α-position of a carbonyl group. Benzene is the simplest of the arenes, a family of organic compounds An organic compound is any member of a large class of chemical compounds whose molecules contain carbon. ... Organic chemistry is a specific discipline within chemistry which involves the scientific study of the structure, properties, composition, reactions, and preparation (by synthesis or by other means) of chemical compounds consisting primarily of carbon and hydrogen, which may contain any number of other elements, including nitrogen, oxygen, halogens as well... In organic chemistry, functional groups (or moieties) are specific groups of atoms within molecules, that are responsible for the characteristic chemical reactions of those molecules. ... // Hydroxyl group The term hydroxyl group is used to describe the functional group -OH when it is a substituent in an organic compound. ... Carbonyl group In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double-bonded to an oxygen atom : C=O. The term carbonyl can also refer to carbon monoxide as a ligand in an inorganic or organometallic complex (a metal carbonyl, e. ...

Contents

Synthesis of acyloins

Classic organic reactions exist for the synthesis of acyloins.

In chemistry, the acyloin condensation is a reductive coupling of two carboxylic esters using metallic sodium to give an α-hydroxyketone, also known as an acyloin. ... The Benzoin condensation is a condensation reaction between two aromatic aldehydes, especially benzaldehyde that is catalyzed by a cyanide. ... Carbonyl group In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double-bonded to an oxygen atom : C=O. The term carbonyl can also refer to carbon monoxide as a ligand in an inorganic or organometallic complex (a metal carbonyl, e. ... Carbonyl group In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double-bonded to an oxygen atom : C=O. The term carbonyl can also refer to carbon monoxide as a ligand in an inorganic or organometallic complex (a metal carbonyl, e. ... General Name, Symbol, Number molybdenum, Mo, 42 Chemical series transition metals Group, Period, Block 6, 5, d Appearance gray metallic Standard atomic weight 95. ... A peroxide is a compound containing an oxygen-oxygen single bond. ... Pyridine is a chemical compound with the formula C5H5N. It is a liquid with a distinctively putrid odour. ... Hexamethylphosphoramide (abbreviated HMPA) is a colorless organic liquid with the formula [(CH3)2N]3PO. HMPA is the oxide of the highly basic tertiary phosphine P(NMe2)3. ...

Enolate oxidation by sulfonyloxaziridines

Enolates can be oxidized by sulfonyloxaziridines [1] [2]. The enolate reacts by nucleophilic displacement at the electron deficient oxygen of the oxaziridine ring. Enol (or, more officially, but less commonly: alkenol) is an alkene with hydroxyl group on one of the carbon atoms of the double bond. ... In chemistry, nucleophilic substitution is a class of substitution reaction in which an electron-rich nucleophile attacks a molecule and replaces a group or atom, called the leaving group. ...

Enolate oxidation by sulfonyloxaziridine

This reaction type is extended to asymmetric synthesis by the use of chiral oxaziridines derived from camphor (camphorsulfonyl oxaziridine). Each isomer gives exclusive access to one of the two possible enantiomers. This modification is applied in the Holton Taxol total synthesis. The two optical isomers of bromochlorofluoromethane Asymmetric synthesis, also called chiral synthesis, enantioselective synthesis or stereoselective synthesis, is organic synthesis which introduces one or more new and desired elements of chirality. ... Optical isomerism is a form of isomerism (specifically stereoisomerism) whereby the different 2 isomers are the same in every way except being non-superimposable mirror images* of each other. ... R-phrases 11-20/21/22-36/37/38 S-phrases 16-26-36 RTECS number EX1260000 (R) EX1250000 (S) Supplementary data page Structure and properties n, εr, etc. ... In chemistry, enantiomers (from the Greek ἐνάντιος, opposite, and μέρος, part or portion) are stereoisomers that are nonsuperimposable complete mirror images of each other, much as ones left and right hands are the same but opposite. ... Holton Taxol total synthesis overview from raw material perspective The Holton Taxol total synthesis, published by Robert A. Holton and his group at Florida State University in 1994 was the first total synthesis of Taxol . The Holton Taxol total synthesis is a good example of a linear synthesis starting from...

two optical isomers of camphorsulfonyl oxaziridine

In the enolate oxidation of the cyclopentaenone below [3] with either camphor enantiomer the trans isomer is obtained because access for the hydroxyl group in the cis position is limited. The use of the standard oxaziridine did not result in an acyloin. In chemistry, geometric isomerism is a form of stereoisomerism and describes the orientation of functional groups at the ends of a bond around which no rotation is possible. ...

enolate oxidation example ref. Hughes 2005

Reactions of acyloins

  • Reduction of acyloins give diols.
  • Oxidation of acyloins give diones.
  • Some acyloins rearrange with positions swapped under the influence of base in the Lobry-de Bruyn-van Ekenstein transformation
  • A similar reaction is the so-called Voight amination [4] where an acyloin reacts with a primary amine and phosphorus pentoxide to an alpha-keto amine [5]:
Voight amination
  • Indole synthesis[6], compare Bischler-Möhlau

Organic reductions or organic oxidations or organic redox reactions are redox reactions that take place with organic compounds. ... A diol is a chemical compound containing two hydroxyl groups (-OH groups). ... Organic reductions or organic oxidations or organic redox reactions are redox reactions that take place with organic compounds. ... The Lobry-de Bruyn-van Ekenstein transformation also known as the Lobry-de Bruyn-van-Alberda-van-Ekenstein transformation is a base catalyzed Aldose-Ketose-Isomerization in carbohydrate chemistry [1] . A typical rearrangement reaction is that between glyceraldehyde and dihydroxyacetone in a chemical equilibrium. ... The general structure of an amine Amines are organic compounds and a type of functional group that contain nitrogen as the key atom. ... Phosphorus pentoxide, perhaps more accurately diphosphorus pentoxide, is so called because of its empirical formula P2O5, as should be expected of any element in oxidation number +5. ... The Bischler-Möhlau indole synthesis is a chemical reaction that forms a 2-aryl-indole from a 2-bromo-acetophenone and excess aniline. ...

References

  1. ^ Synthesis of .alpha.-hydroxycarbonyl compounds (acyloins): direct oxidation of enolates using 2 sulfonyloxaziridines Franklin A. Davis, Lal C. Vishwakarma, Joanne G. Billmers, John Finn J. Org. Chem.; 1984; 49(17); 3241-3243. Abstract
  2. ^ Asymmetric Oxidation of Ester and Amide Enolates Using New (Camphorylsulfony1)oxaziridines Davis, F. A.; Haque, M. S.; Ulatowski, T. G.; Towson, J. C. J. Org. Chem. 1986, 51, 2402. Abstract
  3. ^ An Electrochemical Approach to the Guanacastepenes Chambers C. Hughes, Aubry K. Miller, and Dirk Trauner ORGANIC LETTERS 2005 Vol. 7, No. 16 3425-3428 Article
  4. ^ E. von Meyer, Karl Voigt (1886). "Ueber die Einwirkung von primären aromatischen Aminen auf Benzoïn". Journal für Praktische Chemie 34: 1-27. doi:10.1002/prac.18860340101.
  5. ^ Amines: Synthesis, Properties and Applications Stephen A. Lawrence 2004 Cambridge University Press ISBN 0521782848
  6. ^ Roth, Lepke (1971): Archiv der Pharmazie, 159
The Journal of Organic Chemistry (abbreviated as ) is a scientific journal for original contributions of fundamental research in organic and bioorganic chemistry. ... The Journal of Organic Chemistry (abbreviated as ) is a scientific journal for original contributions of fundamental research in organic and bioorganic chemistry. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ...

 
 

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