PYRENE

Pyrene is a colorless solid, solid and solutions have a slight blue fluorescence. 
Pyrene is used in biochemical research.
Pyrene is a parent class of polycyclic aromatic hydrocarbons containing four fused rings.

CAS Number: 129-00-0
EC Number: 204-927-3
IUPAC Name: Pyrene
Chemical Formula: C16H10

Other names: PYRENE, 129-00-0, Benzo[def]phenanthrene, Pyren, beta-Pyrene, Benzo(def)phenanthrene, .beta.-Pyrene, C16H10, CHEBI:39106, 9E0T7WFW93, CHEMBL279564, Coal tar pitch volatiles:pyrene, DTXSID3024289, NSC-17534, NSC-66449, Pyrene sublimed grade, 1228182-40-8, 1346601-04-4, NCGC00090910-03, Pyren [German], 41496-25-7, CCRIS 1256, HSDB 4023, Pyrene[def]phenanthrene, EINECS 204-927-3, NSC 17534, UNII-9E0T7WFW93, AI3-23977, Pyrene, Powder, Coal tar pitch volatiles: pyrene, Pyren(GERMAN), MFCD00004136, Pyrene, 98%, Pyrene-[13C6], PYRENE [HSDB], PYRENE [IARC], {Benzo[def]phenanthrene}, Pyrene-[13C16], PYRENE [MI], Epitope ID:119715, EC 204-927-3, Pyrene, analytical standard, Pyrene, crystalline, 95%, Pyrene (ACD/Name 4.0), BIDD:ER0347, Pyrene, sublimed grade, 99%, DTXCID804289, Pyrene (purified by sublimation), HMS3749I11, CS-B1735, NSC17534, NSC66449, WLN: L666 B6 2AB PJ, ZINC1758808, Pyrene 10 microg/mL in Cyclohexane, Tox21_400063, BDBM50214608, Pyrene 10 microg/mL in Acetonitrile, STL570454, AKOS000269680, Pyrene 100 microg/mL in Acetonitrile, Pyrene-4,5,9,10-[13C4], NCGC00090910-01, NCGC00090910-02, NCGC00090910-04, AS-13613, CAS-129-00-0, FT-0622695, FT-0674169, P1104, P2072, Pyrene, BCR(R) certified Reference Material, EN300-174930, A805889, AB-131/40897138, Pyrene, purum, for fluorescence, >=97.0% (GC), Q415723, Pyrene, certified reference material, TraceCERT(R), Q-201641, Z57901968, Pyrene, puriss. p.a., for fluorescence, >=99.0% (GC), Pyrene, certified reference material, 1000 mug/mL in methanol, 129-00-0 [RN], 1307225 [Beilstein], 204-927-3 [EINECS], Benzo[def]phenanthrene, L666 B6 2AB PJ [WLN], MFCD00004136 [MDL number], Pirene [Italian], Pyren [German] [ACD/IUPAC Name], Pyrene [ACD/Index Name] [ACD/IUPAC Name] [Wiki], Pyrène [French] [ACD/IUPAC Name], UR2450000, UR2450000 [RTECS], Пирен [Russian], ピレン [Japanese], 芘 [Chinese], 1280594-97-9 [RN], 128076-63-1 [RN], Benzo(def)phenanthrene, C030984, N-(2,4,6-Trinitrophenyl)-2-pyridinamine [ACD/IUPAC Name], N-(2,4,6-TRINITROPHENYL)PYRIDIN-2-AMINE, NCGC00090910-02, Pireno [Portuguese], Pyren [German], QA-3370, ST5214713, β-pyrene, β-Pyrene

This yellow solid is the smallest peri-fused PAH (one where the rings are fused through more than one face). 
Pyrene forms during incomplete combustion of organic compounds.
Pyrene is a colorless solid, solid and solutions have a slight blue fluorescence. 
Pyrene is used in biochemical research.

Pyrene is a parent class of polycyclic aromatic hydrocarbons containing four fused rings.
Pyrene is an ortho- and peri-fused polycyclic arene consisting of four fused benzene rings, resulting in a flat aromatic system. 
Pyrene has a role as a fluorescent probe and a persistent organic pollutant.

Aromatic discotic liquid crystals which exhibits photogeneration of electron-hole pair are used widely in light emitting diodes, photovoltaic cells and field effect transistors. 
Pyrene is an aromatic discotic crystal which is widely used as a fluorescent dye or as an ambipolar charge carrier in Organic Light Emitting Diodes.

Pyrene is registered under the REACH Regulation and is manufactured in and / or imported to the European Economic Area, for intermediate use only.
Pyrene is used at industrial sites and in manufacturing.

Pyrene is a pale yellow crystalline hydrocarbon C16H10 that fluoresces blue in solution, that is obtained from coal-tar distillation, from petroleum cracking, and from stupp and is also made synthetically, and that consists structurally of a cluster of four compactly fused benzene rings

Pyrene is one of a group of chemicals called polycyclic aromatic hydrocarbons, PAHs for short. 
PAHs are often found together in groups of two or more. 

They can exist in over 100 different combinations but the most common are treated as a group of 15. 
PAHs are found naturally in the environment but they can also be man-made. 

Pyrene is colorless crystal-like solid but can also look yellow. 
PAHs are created when products like coal, oil, gas, and garbage is burned but the burning process is not complete.

Very little information is available on the individual chemicals within the PAH group.
Most of the information available is for the PAH group as a whole. 

Pyrene is a polycyclic aromatic hydrocarbon (PAH) consisting of four fused benzene rings, resulting in a flat aromatic system.
The chemical formula is C16H10. 

This colourless solid is the smallest peri-fused PAH (one where the rings are fused through more than one face). 
Pyrene forms during incomplete combustion of organic compounds. 
Although Pyrene is not as problematic as benzopyrene, animal studies have shown pyrene is toxic to the kidneys and the liver.

Pyrene is found to be a component of coal tar, pitch and used for production of dyes, plastics, benz[a]pyrene and pesticides. 
Pyrene has been used as a model compound for metabolism of high molecular weight PAH. 

In M. vanbalenii PYR-1, metabolism of pyrene starts with hydroxylation to form cis-4,5-dihydroxy-4,5-dihydropyrene, which is converted to 4,5-dihydroxypyrene by the action of dehydrogenase. 
4,5-Dihydroxypyrene is ring-cleaved by dioxygenase to yield phenanthrene 4,5-dicarboxylate, which is further decarboxylated to yield phenanthrene-4-carboxylate. 

Subsequent actions of carboxylate dioxygenase and dehydrogenase, Pyrene is converted to 3,4-dihydroxyphenanthrene and further metabolism proceeds via phenanthrene metabolic route. 
In an alternate pathway, pyrene is oxidized through pyrene-4,5-monooxygenase to yield pyrene-4,5-oxide. 
An epoxide hydrolase enzyme further convert Pyrene to trans-4,5-dihydroxy-4,5-dihydropyrene.

Pyrene has been used as a starting material for producing optical brighteners and dyes. 
Notable pyrene sources include domestic heating sources, particularly wood burning; gasoline fuel exhaust; coal tar and asphalt; and cigarette smoke. 

Pyrene is commonly found in PAH mixtures, and Pyrene urinary metabolite, 1-hydroxypyrene, has been used widely as an indicator of exposure to PAH chemicals, particularly in occupational exposure studies. 
IARC determined that pyrene was not classifiable as to Pyrene human carcinogenicity.

Pyrene is a polyaromatic hydrocarbon with strong short-wavelength fluorescence. 
Unlike other fluorescent dyes, polyaromatic hydrocarbons are fluorescent probes with a strong sensitivity to the microenvironment. 

Thus, Pyrene fluorescence is different in polar, and nonpolar environments. 
Other effects can also be observed.

When two pyrenes are in close proximity, they form excimers. 
Excimer formation can be easily observed, and quantitatively estimated using fluorescent spectra.

Pyrene azide is a reagent for easy pyrene click chemistry labeling of any alkyne-bearing molecule. 
Pyrene allows turning any molecule into a pyrene-bearing probe.

This azide contains a hydrophilic triethyleneglycol linker to mitigate intrinsic pyrene hydrophobicity and facilitate attachment to biomolecules in aqueous solutions.

Applications of Pyrene:
Pyrene's fluorescence emission spectrum is very sensitive to solvent polarity, so pyrene has been used as a probe to determine solvent environments. 
This is due to Pyrene excited state having a different, non-planar structure than the ground state. 
Certain emission bands are unaffected, but others vary in intensity due to the strength of interaction with a solvent.

Diagram showing the numbering and ring fusion locations of pyrene according to IUPAC nomenclature of organic chemistry.
Pyrenes are strong electron donor materials and can be combined with several materials in order to make electron donor-acceptor systems which can be used in energy conversion and light harvesting applications.

Pyrene and its derivatives are electron-donor materials and can be used to prepare electron donor-acceptor systems for energy conversion and light harvesting applications like OLED and solar cells. 
Pyrene can also be used as a probe to determine the critical micellar concentration of surfactants and to study the protein conformation and conformational changes by fluorescence spectroscopy.

Uses of Pyrene:
Most of the Pyrene's are used to conduct research. 
Like most PAHs, pyrene is used to make dyes, plastics and pesticides.
Pyrene has also been used to make another PAH called benzo(a)pyrene.

Pyrene is used in research.
Pyrene is used as a starting material in the production of optical brighteners and dyes.
Pyrene is a by-product of the pyrolysis of organic matter and is present in coal tar distillates, diesel exhaust, automobile exhaust, tobacco smoke, barbecue smoke, wood smoke, lake sediments, waste oils, and sewage. 

Optical brighteners can be synthesized by reaction of pyrene with a complex of cyanuric chloride and aluminum chloride.
By analogy to fluoranthene, pyrene and alkylpyrenes can be used as additives in electro-insulating oils as well as in epoxy resins for electrical insulation.

Pyrene from coal-tar has been used as a starting material for the synthesis of benzo(a)pyrene.
Pyrene itself can serve as an electron donor to enhance the blackness in pencil leads.

Pyrene's are released into the environment via the combustion of fossil fuels, coke oven emissions and vehicle exhausts, as well as naturally from forest fires and vocanic eruptions. 
Pyrene's from these sources may contaminate nearly water systems. 
They are also found in coal tar and charbroiled food.

Uses at industrial sites:
Pyrene has an industrial use resulting in manufacture of another substance (use of intermediates).
Pyrene is used for the manufacture of: chemicals.
Release to the environment of Pyrene can occur from industrial use: as an intermediate step in further manufacturing of another substance (use of intermediates).

Industry Uses:
Pigments

Features and Benefits of Pyrene:
Long intrinsic fluorescence lifetime, lipophilic hydrocarbon, facilitates charge transport due to the strong p-p interactions in the solid state.
π-system does not require protection during functionalization

Occurrence and Properties of Pyrene:
Pyrene was first isolated from coal tar, where Pyrene occurs up to 2% by weight. 
As a peri-fused PAH, pyrene is much more resonance-stabilized than Pyrene five-member-ring containing isomer fluoranthene. 

Therefore, Pyrene is produced in a wide range of combustion conditions. 
For example, automobiles produce about 1 μg/km.

Reactions:
Oxidation with chromate affords perinaphthenone and then naphthalene-1,4,5,8-tetracarboxylic acid. 
Pyrene undergoes a series of hydrogenation reactions and is susceptible to halogenation, Diels-Alder additions, and nitration, all with varying degrees of selectivity.
Bromination occurs at one of the 3-positions.

Reduction with sodium affords the radical anion. 
From this anion, a variety of pi-arene complexes can be prepared.

Photophysics:
Pyrene and its derivatives are used commercially to make dyes and dye precursors, for example pyranine and naphthalene-1,4,5,8-tetracarboxylic acid. 
Pyrene has strong absorbance in UV-Vis in three sharp bands at 330 nm in DCM. 

The emission is close to the absorption, but moving at 375 nm.
The morphology of the signals change with the solvent. 

Pyrene derivatives are also valuable molecular probes via fluorescence spectroscopy, having a high quantum yield and lifetime (0.65 and 410 nanoseconds, respectively, in ethanol at 293 K). 
Pyrene was the first molecule for which excimer behavior was discovered.

Such excimer appears around 450 nm. 
Theodor Förster reported this in 1954.

Manufacturing Methods of Pyrene:
Pyrene is found in products of incomplete combustion, fossil fuels, and high-temperature coal tar fractions, which on average contain ca. 2% pyrene. 
Pyrene is recovered from a fraction crystallizing above 110 °C, which is obtained by redistillation of the high-boiling anthracene oil II or pitch distillate. 

Pure pyrene is produced by recrystallization, e.g., from solvent naphtha or by fractional crystallization from the melt, followed by dephenolation and debasing, and by refining with 80% sulfuric acid.
Alternatively, pyrene-accompanying brasane (2, 3-benzodiphenylene oxide) can be separated by recrystallization from xylene in the presence of iron(III) chloride. 
Traces of tetracene are removed by reaction with maleic anhydride.

Pyrene is obtained by the destructive hydrogenation of hard coal.
Pyrene can be synthesized via bromination of o,o'-ditolyl. 
The resulting intermediate is transformed into Pyrene corresponding dicarboxylic acid via dinitrile intermediates. 

Cyclization takes place in the presence of zinc dust. 
An alternative route to pyrene is the reaction of peri-trimethylenenapthalene with malonyl chloride and AlCl3. 
Pyrene is also accessible via the Reformatsky reaction of 4-keto-1,2,3,4-tetrahydrophenanthrene

Human Metabolite Information of Pyrene:

Cellular Locations:
Membrane

Analytic Laboratory Methods of Pyrene:

Method: NIOSH 5515, Issue 2
Procedure: gas chromatography, capillary column, flame ionization detection
Analyte: pyrene
Matrix: air
Detection Limit: 0.3 to 0.5 ug /sample.

Method: NIOSH 5506, Issue 3
Procedure: high performance liquid chromatography with fluorescence/ultraviolet detector
Analyte: pyrene
Matrix: air
Detection Limit: 0.0010-0.30 ug/sample.

Method: OSHA 58
Procedure: high performance liquid chromatography with a fluorescence or ultraviolet detector
Analyte: pyrene
Matrix: air
Detection Limit: 0.260 ug/cu m.

Method: DOE OM100R
Procedure: gas chromatography/mass spectrometry with ion trap detector
Analyte: pyrene
Matrix: solid waste matrices, soils, and groundwater
Detection Limit: 53 ug/L.

Reactivity:
Forms explosive mixtures with air on intense heating.
A range from approx. 15 Kelvin below the flash point is to be rated as critical.

The following applies in general to flammable organic substances and mixtures:
In correspondingly fine distribution, when whirled up a dust explosion potential may generally be assumed.

Molecular Weight: 202.25
XLogP3: 4.9
Exact Mass: 202.078250319
Monoisotopic Mass: 202.078250319

Heavy Atom Count: 16
Complexity: 217
Covalently-Bonded Unit Count: 1
Compound Is Canonicalized: Yes