Chrysanthemic acid 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 ...

that is related to a variety of natural and synthetic

insecticide Insecticides are pesticides used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. The major use of insecticides is in agriculture, but they are also used in home and garden settings, i ...

s. It is related to the

pyrethrin The pyrethrins are a class of organic compounds normally derived from ''Chrysanthemum cinerariifolium'' that have potent Insecticide, insecticidal activity by targeting the nervous systems of insects. Pyrethrin naturally occurs in chrysanthemum f ...

I and II, as well as the

pyrethroid A pyrethroid is an organic compound similar to the natural pyrethrins, which are produced by the flowers of pyrethrums (''Chrysanthemum cinerariaefolium'' and ''Chrysanthemum coccineum, C. coccineum''). Pyrethroids are used as commercial and hou ...

s. One of the four

stereoisomer In stereochemistry, stereoisomerism, or spatial isomerism, is a form of isomerism in which molecules have the same molecular formula and sequence of bonded atoms (constitution), but differ in the three-dimensional orientations of their atoms in ...

s, (1''R'',3''R'')- or (+)-''trans''-chrysanthemic acid (pictured), is the acid part of the ester

pyrethrin I Pyrethrin I is one of the two pyrethrins, natural organic compounds with potent insecticidal activity. It is an ester of (+)-''trans''- chrysanthemic acid with (''S'')-(''Z'')- pyrethrolone. Total synthesis The synthesis of pyrethrin I involves t ...

, which occurs naturally in the seed cases of ''

Chrysanthemum Chrysanthemums ( ), sometimes called mums or chrysanths, are flowering plants in the Asteraceae family. They are native to East Asia and northeastern Europe. Most species originate from East Asia, and the center of diversity is in China. Co ...

cinerariaefolium''. Many synthetic pyrethroids, for example the allethrins, are esters of all four stereoisomers. Staudinger and Ružička named chrysanthemic acid in 1924.H. Staudinger, L. Ružička: "Insektentotende Stoffe H. Zur Konstitution der Chrysanthemummonocarbonsiiure und -dicarbonsiiure", Helv. Chem. Acta 7 (1924) 201

Biosynthesis

Chrysanthemic acid is derived from its

pyrophosphate In chemistry, pyrophosphates are phosphorus oxyanions that contain two phosphorus atoms in a linkage. A number of pyrophosphate salts exist, such as disodium pyrophosphate () and tetrasodium pyrophosphate (), among others. Often pyrophosphates a ...

ester, which in turn is produced naturally from two molecules of dimethylallyl diphosphate.

Industrial synthesis

Chrysanthemic acid is produced industrially in a

cyclopropanation In organic chemistry, cyclopropanation refers to any chemical process which generates cyclopropane () Ring (chemistry), rings. It is an important process in modern chemistry as many useful compounds bear this motif; for example pyrethroid insectic ...

reaction of a

diene In organic chemistry, a diene ( ); also diolefin, ) or alkadiene) is a covalent compound that contains two double bonds, usually among carbon atoms. They thus contain two alk''ene'' units, with the standard prefix ''di'' of systematic nome ...

as a mixture of cis- and trans isomers, followed by hydrolysis of the ester: ChrysanthemicAcidSynthesis

Many pyrethroids are accessible by re-esterification of chrysanthemic acid ethyl ester - a perfume ingredient.

References

{{Insecticides Monoterpenes Cyclopropanes Carboxylic acids