Geranylacetone 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 ...

with the formula CH₃C(O)(CH₂)₂CH=C(CH₃)(CH₂)₂CH=C(CH₃)₂. A colorless oil, it is the product of coupling

geranyl Geraniol is a monoterpenoid and an alcohol. It is the primary component of citronella oil and is a primary component of rose oil and palmarosa oil. It is a colorless oil, although commercial samples can appear yellow. It has low solubility in w ...

and

acetonyl Acetone (2-propanone or dimethyl ketone) is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile, and flammable liquid with a characteristic pungent odor. Acetone is miscible w ...

groups. It is a precursor to synthetic

squalene Squalene is an organic compound. It is a triterpene with the formula C30H50. It is a colourless oil, although impure samples appear yellow. It was originally obtained from shark liver oil (hence its name, as '' Squalus'' is a genus of sharks). ...

Synthesis and occurrence

Geranylacetone can be produced by

transesterification Transesterification is the process of exchanging the organic functional group R″ of an ester with the organic group R' of an alcohol. These reactions are often catalyzed by the addition of an acid or base catalyst. Strong acids catalyze the r ...

ethyl acetoacetate The organic compound ethyl acetoacetate (EAA) is the ethyl ester of acetoacetic acid. It is a colorless liquid. It is widely used as a chemical intermediate in the production of a wide variety of compounds. Preparation At large scale, ethyl ac ...

with

linalool Linalool () refers to two enantiomers of a naturally occurring terpene alcohol found in many flowers and spice plants. Together with geraniol, nerol, and citronellol, linalool is one of the rose alcohols. Linalool has multiple commercial app ...

: : The esterification of linalool can also be effected with

ketene In organic chemistry, a ketene is an organic compound of the form , where R and R' are two arbitrary valence (chemistry), monovalent functional group, chemical groups (or two separate Substituent, substitution sites in the same molecule). The na ...

or isopropenyl methyl ether. The resulting linalyl ester undergoes

Carroll rearrangement The Carroll rearrangement is a rearrangement reaction in organic chemistry and involves the transformation of a β-ketone, keto allyl ester into a α-allyl-β-ketocarboxylic acid. This organic reaction is accompanied by decarboxylation and the fina ...

to give geranylacetone. Geranyl acetone is a precursor to isophytol, which is used in the manufacture of

Vitamin E Vitamin E is a group of eight compounds related in molecular structure that includes four tocopherols and four tocotrienols. The tocopherols function as fat-soluble antioxidants which may help protect cell membranes from reactive oxygen speci ...

. Other derivatives of geranyl acetone are

farnesol Farnesol is a natural 15-carbon organic compound which is an acyclic sesquiterpene alcohol. Under standard conditions, it is a colorless liquid. It is hydrophobic, and thus insoluble in water, but miscible with oils. As the pyrophosphate ester, ...

and

nerolidol Nerolidol, also known as peruviol and penetrol , is a naturally occurring sesquiterpene alcohol. A colorless liquid, it is found in the essential oils of many types of plants and flowers. There are four isomers of nerolidol', which differ in the ...

. Geranylacetone is a flavor component of many plants including

rice Rice is a cereal grain and in its Domestication, domesticated form is the staple food of over half of the world's population, particularly in Asia and Africa. Rice is the seed of the grass species ''Oryza sativa'' (Asian rice)—or, much l ...

mango A mango is an edible stone fruit produced by the tropical tree '' Mangifera indica''. It originated from the region between northwestern Myanmar, Bangladesh, and northeastern India. ''M. indica'' has been cultivated in South and Southeast As ...

, and

tomato The tomato (, ), ''Solanum lycopersicum'', is a plant whose fruit is an edible Berry (botany), berry that is eaten as a vegetable. The tomato is a member of the nightshade family that includes tobacco, potato, and chili peppers. It originate ...

es. Together with other ketones, geranylacetone results from the degradation of vegetable matter by

ozone Ozone () (or trioxygen) is an Inorganic compound, inorganic molecule with the chemical formula . It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope , break ...

Biosynthesis

It arises by the oxidation of certain

carotenoid Carotenoids () are yellow, orange, and red organic pigments that are produced by plants and algae, as well as several bacteria, archaea, and fungi. Carotenoids give the characteristic color to pumpkins, carrots, parsnips, corn, tomatoes, cana ...

s. Such reaction are catalyzed by carotenoid oxygenase.{{cite journal , doi=10.1111/j.1365-313X.2004.02263.x, title=The Tomato Carotenoid Cleavage Dioxygenase 1 Genes Contribute to the Formation of the Flavor Volatiles β-Ionone, Pseudoionone, and Geranylacetone, year=2004, last1=Simkin, first1=Andrew J., last2=Schwartz, first2=Steven H., last3=Auldridge, first3=Michele, last4=Taylor, first4=Mark G., last5=Klee, first5=Harry J., journal=The Plant Journal, volume=40, issue=6, pages=882–892, pmid=15584954, doi-access=free

References

Monoterpenes Flavors