In organic chemistry, acyloins or α-hydroxy ketones[1] are a class of organic compounds of the general form R−C(=O)−CR'(OH)−R", composed of a hydroxy group (−OH) adjacent to a ketone group (>C=O). The name acyloin is derived from the fact that they are formally derived from reductive coupling of carboxylic acyl groups (R−C(=O)−).[1] They are one of the two main classes of hydroxy ketones, distinguished by the position of the hydroxy group relative to the ketone; in this form, the hydroxy is on the alpha carbon, explaining the secondary name of α-hydroxy ketone.
^ abIUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "acyloins". doi:10.1351/goldbook.A00126
In organic chemistry, acyloins or α-hydroxy ketones are a class of organic compounds of the general form R−C(=O)−CR'(OH)−R", composed of a hydroxy group...
Acyloin condensation is a reductive coupling of two carboxylic esters using impure metallic sodium to yield an α-hydroxyketone, also known as an acyloin...
between aromatic aldehydes or glyoxals, and results in formation of an acyloin. In the classic example, benzaldehyde is converted to benzoin. The benzoin...
succinate is a particularly versatile building block. It participates in acyloin condensation to give 2-hydroxycyclobutanone. Via condensation with oxalate...
hydroxyketones and alpha hydroxy imines. Reactions of type 4 are also called acyloin rearrangements. While similar to the pinacol rearrangement, the semipinacol...
synthetically. They readily react with the neutral aldehyde to form an acyloin dimer. Hence, synthetic chemists have developed various acyl anion synthetic...
compounds with various aromas. As such it finds some use as a flavoring. Acyloin, the simplest secondary α-hydroxy ketone. Nodzu, Ryuzaburo (1935). "On...
Normally such compounds are disfavored components in equilibria with acyloins. One special case is catechol, where the C=C subunit is part of an aromatic...
nitriles. Pairs of esters are coupled to give α-hydroxyketones in the acyloin condensation As a class, esters serve as protecting groups for carboxylic...
n-hexyl radical attacked by oxygen). In one study the photolysis of an acyloin derivative in water in presence of hydrogen tetrachloroaurate (HAuCl4)...
a carboxylic acid. Other routes to vic-diols are the hydrogenation of acyloins and the pinacol coupling reaction. 1,3-Diols are often prepared industrially...
this reaction step the alkene group is first oxidized to an intermediate acyloin by action of osmium(III) chloride, oxone (sacrificial catalyst) and sodium...
and R−C(=O)−CH2−C(OH)−R' (beta). Alpha-hydroxy ketones are also called acyloins. They are commonly formed by condensation or reductive coupling of two...
medium-sized ring compounds with 8 to 12 members from dicarboxylic acid esters by acyloin condensation and explained their unusual chemical reactivity by a "nonclassical"...
substituents (i.e., defined stereochemistry). These general reactions include: Acyloin condensation; Anodic oxidations; and the Dieckmann condensation as applied...
of the reaction has been known to occur in many substrates bearing the acyloin functional group. The picture below shows the ring expansion of a cyclopentane...
cheaper oxidant. Alternatively, vicinal diols or their oxidized sequelae (acyloins or α-hydroxy acids) can be oxidized with cleavage to two aldehydes or an...
methylene blue. In the first step an acyloin of glucose is formed. The next step is a redox reaction of the acyloin with methylene blue in which the glucose...
elevated temperatures, while another uses acyloin condensation of the ethyl ester of pimelic acid the acyloin again followed by oxidation by bromine. An...
Finn, John (1 August 1984). "Synthesis of α-hydroxycarbonyl compounds (acyloins): direct oxidation of enolates using 2-sulfonyloxaziridines". The Journal...
Decarboxylase: A Molecular Modeling Study of Pyruvate Decarboxylation and Acyloin Formation". J. Am. Chem. Soc. 118 (8): 1867–1873. doi:10.1021/ja951830t...
been reported. A prime example using PSL effectively resolves racemic acyloins in the presence of triethylamine and vinyl acetate as the acylating agent...
Acetoin, also known as 3-hydroxybutanone or acetyl methyl carbinol, is an organic compound with the formula CH3CH(OH)C(O)CH3. It is a colorless liquid...
transformations that are enabled or enhanced intramolecularly. For example, the acyloin condensation of diesters almost uniquely produces 10-membered carbocycles...
double bonds to single bonds. For example, sebacoin, derived from the acyloin condensation of dimethyl sebacate, is hydrogenated to 1,2-cyclodecanediol...
Global Information