Oct-1-en-3-one (CH₂=CHC(=O)(CH₂)₄CH₃), also known as 1-octen-3-one, is the

odorant An aroma compound, also known as an odorant, aroma, fragrance or flavoring, is a chemical compound that has a smell or odor. For an individual chemical or class of chemical compounds to impart a smell or fragrance, it must be sufficiently vol ...

that is responsible for the typical "metallic" smell of

metal A metal (from Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typicall ...

s and

blood Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood in the cir ...

coming into contact with

skin Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other animal coverings, such as the arthropod exoskeleton, have different de ...

. Oct-1-en-3-one has a strong metallic mushroom-like odor with an

odor detection threshold The odor detection threshold is the lowest concentration of a certain odor compound that is perceivable by the human sense of smell. The threshold of a chemical compound is determined in part by its shape, polarity, partial charges, and molecu ...

of 0.03–1.12 µg/m³ and it is the main compound responsible for the "smell of metal", followed by

decanal Decanal is an organic compound classified as an aldehyde with the chemical formula C10H20O. Occurrence Decanal occurs naturally in citrus, along with octanal, citral, and sinensal, in buckwheat Buckwheat (''Fagopyrum esculentum''), or com ...

(smell: orange skin, flowery) and

nonanal Nonanal, also called nonanaldehyde, pelargonaldehyde or Aldehyde C-9, is an aldehyde. A colourless, oily liquid, nonanal is a component of perfumes. Although it occurs in several natural oils, it is produced commercially by hydroformylation of 1- ...

(smell: tallowy, fruity). Oct-1-en-3-one is the degradative reduction product of the

chemical reaction A chemical reaction is a process that leads to the IUPAC nomenclature for organic transformations, chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the pos ...

of skin lipid peroxides and Fe²⁺. Skin

lipid Lipids are a broad group of naturally-occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids includ ...

peroxide In chemistry, peroxides are a group of compounds with the structure , where R = any element. The group in a peroxide is called the peroxide group or peroxo group. The nomenclature is somewhat variable. The most common peroxide is hydrogen ...

s are formed from skin lipid by

oxidation Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a ...

, either enzymatically by

lipoxygenase Lipoxygenases () are a family of (non-heme) iron-containing enzymes most of which catalyze the dioxygenation of polyunsaturated fatty acids in lipids containing a cis,cis-1,4- pentadiene into cell signaling agents that serve diverse roles as aut ...

s or by

air The atmosphere of Earth is the layer of gases, known collectively as air, retained by Earth's gravity that surrounds the planet and forms its planetary atmosphere. The atmosphere of Earth protects life on Earth by creating pressure allowing f ...

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as ...

. Oct-1-en-3-one is a ketone analog of the

alkene In organic chemistry, an alkene is a hydrocarbon containing a carbon–carbon double bond. Alkene is often used as synonym of olefin, that is, any hydrocarbon containing one or more double bonds.H. Stephen Stoker (2015): General, Organic, an ...

1-octene.

Natural occurrences

It is also produced by ''

Uncinula necator ''Uncinula necator'' (syn. ''Erysiphe necator'') is a fungus that causes powdery mildew of grape. It is a common pathogen of Vitis species, including the wine grape, ''Vitis vinifera''. The fungus is believed to have originated in North America ...

'', a fungus that causes powdery mildew of grape.

References

{{DEFAULTSORT:Octen-3-one, 1- Flavors Enones

Natural occurrences

See also

References