Methylcyclopentenolone
   HOME

TheInfoList



OR:

2-Hydroxy-3-methyl-2-cyclopenten-1-one is an
organic compound Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...
related to
1,2-cyclopentanedione 1,2-Cyclopentanedione is the organic compound with the formula (CH2)3(CO)2. It is one of two isomeric cyclopentanediones, the other being 1,3-cyclopentanedione. It was first prepared by base-induced condensation of di ethylglutarate with dieth ...
. It is the
enol In organic chemistry, enols are a type of functional group or intermediate in organic chemistry containing a group with the formula (R = many substituents). The term ''enol'' is an abbreviation of ''alkenol'', a portmanteau deriving from "-ene ...
tautomer In chemistry, tautomers () are structural isomers (constitutional isomers) of chemical compounds that readily interconvert. The chemical reaction interconverting the two is called tautomerization. This conversion commonly results from the reloca ...
of the diketone 3-methylcyclopentane-1,2-dione. Being an enol, the compound is often called methylcyclopentenolone. It is a colorless solid.


Synthesis and structure

The compound is prepared by base-catalyzed condensation of 1-hydroxyhexane-2,5-dione, a derivative of
hydroxymethylfurfural Hydroxymethylfurfural (HMF), also known as 5-(hydroxymethyl)furfural, is an organic compound formed by the dehydration of reducing sugars. It is a white low-melting solid (although commercial samples are often yellow) which is highly soluble in b ...
. The structure has been confirmed by
X-ray crystallography X-ray crystallography is the experimental science of determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to Diffraction, diffract in specific directions. By measuring th ...
. Quantum calculations also indicate that the enol is strongly favored relative to the diketo tautomer. Furthermore, the enolization occurs at the methyl-substituted carbon.


Use and occurrence

It is one of many products from the
pyrolysis Pyrolysis is a process involving the Bond cleavage, separation of covalent bonds in organic matter by thermal decomposition within an Chemically inert, inert environment without oxygen. Etymology The word ''pyrolysis'' is coined from the Gree ...
of
lignocellulose Lignocellulose refers to plant dry matter (biomass), so called lignocellulosic biomass. It is the most abundantly available raw material on the Earth for the production of Biofuel, biofuels. It is composed of two kinds of carbohydrate polymers, c ...
. It is used in flavors and perfumery for its
maple ''Acer'' is a genus of trees and shrubs commonly known as maples. The genus is placed in the soapberry family Sapindaceae.Stevens, P. F. (2001 onwards). Angiosperm Phylogeny Website. Version 9, June 2008 nd more or less continuously updated si ...
- or
caramel Caramel ( or ) is a range of food ingredients made by heating sugars to high temperatures. It is used as a flavoring in puddings and desserts, as a filling in bonbons or candy bars, as a topping for ice cream and custard, and as a colorant ...
-like odor. It contributes to the flavor or odor of many foods including wines, coffee, paprika, and salmon. It is sometimes called maple lactone because it occurs in
maple syrup Maple syrup is a sweet syrup made from the sap of maple trees. In cold climates, these trees store starch in their trunks and roots before winter; the starch is then converted to sugar that rises in the sap in late winter and early spring. Ma ...
(it is not, however, a
lactone Lactones are cyclic carboxylic esters. They are derived from the corresponding hydroxycarboxylic acids by esterification. They can be saturated or unsaturated. Lactones are formed by lactonization, the intramolecular esterification of the corresp ...
).


See also

*
1,2-Cyclopentanedione 1,2-Cyclopentanedione is the organic compound with the formula (CH2)3(CO)2. It is one of two isomeric cyclopentanediones, the other being 1,3-cyclopentanedione. It was first prepared by base-induced condensation of di ethylglutarate with dieth ...


References

{{DEFAULTSORT:Hydroxy-3-methyl-2-cyclopenten-1-one, 2- Diketones Cyclopentanes