Perylene or perilene is a

polycyclic aromatic hydrocarbon A polycyclic aromatic hydrocarbon (PAH) is a class of organic compounds that is composed of multiple aromatic rings. The simplest representative is naphthalene, having two aromatic rings and the three-ring compounds anthracene and phenanthrene. ...

with the

chemical formula In chemistry, a chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, ...

C₂₀H₁₂, occurring as a brown solid. It or its derivatives may be

carcinogen A carcinogen is any substance, radionuclide, or radiation that promotes carcinogenesis (the formation of cancer). This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes. Several radioactive substan ...

ic, and it is considered to be a hazardous

pollutant A pollutant or novel entity is a substance or energy introduced into the environment that has undesired effects, or adversely affects the usefulness of a resource. These can be both naturally forming (i.e. minerals or extracted compounds like oi ...

. In

cell membrane The cell membrane (also known as the plasma membrane (PM) or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of all cells from the outside environment ( ...

cytochemistry Cytochemistry is the branch of cell biology dealing with the detection of cell constituents by means of biochemical analysis and visualization techniques. This is the study of the localization of cellular components through the use of staining me ...

, perylene is used as a

fluorescent Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, tha ...

lipid probe. It is the parent compound of a class of

rylene dye A rylene dye is a dye based on the rylene framework of naphthalene units linked in peri-positions. In homologues additional naphthalene units are added, forming compounds — or ''poly(peri-naphthalene)s'' — such as perylene, terrylene and qua ...

Reactions

Like other polycyclic aromatic compounds, perylene is reduced by alkali metals to give a deeply colored radical anion and a dianion. The

diglyme Diglyme, or bis(2-methoxyethyl) ether, is a solvent with a high boiling point. It is an organic compound which is the dimethyl ether of diethylene glycol. (The name ''diglyme'' is a portmanteau of ''diglycol methyl ether''.) It is a colorless li ...

solvates of these salts have been characterized by

X-ray crystallography X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles ...

Emission

Perylene displays blue

fluorescence Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, tha ...

. It is used as a blue-emitting dopant material in

OLEDs An organic light-emitting diode (OLED or organic LED), also known as organic electroluminescent (organic EL) diode, is a light-emitting diode (LED) in which the emission (electromagnetic radiation), emissive electroluminescence, electroluminesc ...

, either pure or substituted. Perylene can be also used as an organic

photoconductor Photoconductivity is an optical and electrical phenomenon in which a material becomes more electrically conductive due to the absorption of electromagnetic radiation such as visible light, ultraviolet light, infrared light, or gamma radiation. W ...

. It has an absorption maximum at 434 nm, and as with all polycyclic aromatic compounds, low water solubility (1.2 x 10⁻⁵ mmol/L). Perylene has a

molar absorptivity Molar may refer to: *Molar (tooth), a kind of tooth found in mammals *Molar (grape), another name for the Spanish wine grape Listan Negro *Molar (unit), a unit of concentration equal to 1 mole per litre *Molar mass * Molar volume *El Molar, Tarrago ...

of 38,500 M⁻¹cm⁻¹ at 435.7 nm. Image:Perylene-LongWaveUV.png, Perylene dissolved in

dichloromethane Dichloromethane (DCM or methylene chloride, methylene bichloride) is an organochlorine compound with the formula . This colorless, volatile liquid with a chloroform-like, sweet odour is widely used as a solvent. Although it is not miscible with ...

exposed to Long Wave UV radiation Image:Perylene-ShortWaveUV.png, Perylene dissolved in dichloromethane exposed to Short Wave UV radiation

Structure

The perylene

molecule A molecule is a group of two or more atoms held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions which satisfy this criterion. In quantum physics, organic chemistry, and bioch ...

consists of two

naphthalene Naphthalene is an organic compound with formula . It is the simplest polycyclic aromatic hydrocarbon, and is a white crystalline solid with a characteristic odor that is detectable at concentrations as low as 0.08 ppm by mass. As an aromati ...

molecules connected by a carbon-carbon bond at the 1 and 8 positions on both molecules. All of the

carbon Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with o ...

atoms in perylene are sp² hybridized. The structure of perylene has been extensively studied by

Biology

Naturally occurring perylene

quinone The quinones are a class of organic compounds that are formally "derived from aromatic compounds

uch as benzene or naphthalene Uch ( pa, ; ur, ), frequently referred to as Uch Sharīf ( pa, ; ur, ; ''"Noble Uch"''), is a historic city in the southern part of Pakistan's Punjab province. Uch may have been founded as Alexandria on the Indus, a town founded by Alexand ...

by conversion of an even number of –CH= groups into –C(=O)– groups with any necessary rearrangement of double ...

s have been identified in

lichens A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among hypha, filaments of multiple fungus, fungi species in a mutualism (biology), mutualistic relationship.Laurera ''Laurera'' is a genus of fungi within the Trypetheliaceae family. Species It was known to have nearly 50 species at one point in time, but most have these have become synonyms for other species, within the ''Astrothelium ''Astrothelium'' is ...

sanguinaria'' Malme and '' Graphis haematites'' Fée.

References

{{PAHs IARC Group 3 carcinogens Membrane biology Polycyclic aromatic hydrocarbons Organic semiconductors Fluorescent dyes