Names | |
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Preferred IUPAC name Phenanthrene | |
Identifiers | |
3D model (JSmol) | |
1905428 | |
ChEBI | |
ChemSpider | |
ECHA InfoCard | 100.001.437 |
EC Number |
|
28699 | |
KEGG | |
MeSH | C031181 |
PubChem CID | |
UNII | |
CompTox Dashboard (EPA) | |
| |
| |
Properties | |
C14H10 | |
Molar mass | 178.234 g·mol−1 |
Appearance | Colorless solid |
Density | 1.18 g/cm3 [1] |
Melting point | 101 °C (214 °F; 374 K) [1] |
Boiling point | 332 °C (630 °F; 605 K) [1] |
1.6 mg/L [1] | |
−127.9·10−6 cm3/mol | |
Hazards | |
NFPA 704 (fire diamond) | |
Flash point | 171 °C (340 °F; 444 K) [1] |
Structure | |
C2v [2] | |
0 D | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Phenanthrene is a polycyclic aromatic hydrocarbon (PAH) with formula C14H10, consisting of three fused benzene rings. It is a colorless, crystal-like solid, but can also appear yellow. Phenanthrene is used to make dyes, plastics, pesticides, explosives, and drugs. It has also been used to make bile acids, cholesterol and steroids. [3]
Phenanthrene occurs naturally and also is a man-made chemical. Commonly, humans are exposed to phenanthrene through inhalation of cigarette smoke, but there are many routes of exposure. Animal studies have shown that phenanthrene is a potential carcinogen. [3] However, according to IARC, it is not identified as a probable, possible or confirmed human carcinogen. [4]
Phenanthrene's three fused rings are angled as in the phenacenes, rather than straight as in the acenes. The compound with a phenanthrene skeleton and nitrogens at the 4 and 5 positions is known as phenanthroline.
Phenanthrene is nearly insoluble in water but is soluble in most low-polarity organic solvents such as toluene, carbon tetrachloride, ether, chloroform, acetic acid and benzene.
Phenanthrene is fluorescent under ultraviolet light, exhibiting a large Stoke shift. [5] It can be used in scintillators.
Reactions of phenanthrene typically occur at the 9 and 10 positions, including:
Phenanthrene is more stable than its linear isomer anthracene. A classic and well established explanation is based on Clar's rule. A novel theory invokes so-called stabilizing hydrogen–hydrogen bonds between the C4 and C5 hydrogen atoms.[ citation needed ]
The Bardhan–Sengupta phenanthrene synthesis is a classic way to make phenanthrenes. [11]
This process involves electrophilic aromatic substitution using a tethered cyclohexanol group using diphosphorus pentoxide, which closes the central ring onto an existing aromatic ring. Dehydrogenation using selenium converts the other rings into aromatic ones as well. The aromatization of six-membered rings by selenium is not clearly understood, but it does produce H2Se.
Phenanthrene can also be obtained photochemically from certain diarylethenes (Mallory reaction):
Other synthesis routes include the Haworth reaction and the Wagner-Meerwein-type ring-expansion, as depicted below:
Ravatite is a natural mineral consisting of phenanthrene. [12] It is found in small amounts among a few coal burning sites. Ravatite represents a small group of organic minerals.
Phenanthrene derivatives occur in plants as phenanthrenoids. They have been reported from flowering plants, mainly in the family Orchidaceae, and a few in the families Dioscoreaceae, Combretaceae and Betulaceae, as well as in the lower plant class Marchantiophyta (liverworts). [13]
Aromatic compounds or arenes usually refers to organic compounds "with a chemistry typified by benzene" and "cyclically conjugated." The word "aromatic" originates from the past grouping of molecules based on odor, before their general chemical properties were understood. The current definition of aromatic compounds does not have any relation to their odor. Aromatic compounds are now defined as cyclic compounds satisfying Hückel's Rule. Aromatic compounds have the following general properties:
Pyrimidine is an aromatic, heterocyclic, organic compound similar to pyridine. One of the three diazines, it has nitrogen atoms at positions 1 and 3 in the ring. The other diazines are pyrazine and pyridazine.
Pyridine is a basic heterocyclic organic compound with the chemical formula C5H5N. It is structurally related to benzene, with one methine group (=CH−) replaced by a nitrogen atom (=N−). It is a highly flammable, weakly alkaline, water-miscible liquid with a distinctive, unpleasant fish-like smell. Pyridine is colorless, but older or impure samples can appear yellow, due to the formation of extended, unsaturated polymeric chains, which show significant electrical conductivity. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. Historically, pyridine was produced from coal tar. As of 2016, it is synthesized on the scale of about 20,000 tons per year worldwide.
Naphthalene is an organic compound with formula C
10H
8. 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 aromatic hydrocarbon, naphthalene's structure consists of a fused pair of benzene rings. It is the main ingredient of traditional mothballs.
Pyrrole is a heterocyclic, aromatic, organic compound, a five-membered ring with the formula C4H4NH. It is a colorless volatile liquid that darkens readily upon exposure to air. Substituted derivatives are also called pyrroles, e.g., N-methylpyrrole, C4H4NCH3. Porphobilinogen, a trisubstituted pyrrole, is the biosynthetic precursor to many natural products such as heme.
Anthracene is a solid polycyclic aromatic hydrocarbon (PAH) of formula C14H10, consisting of three fused benzene rings. It is a component of coal tar. Anthracene is used in the production of the red dye alizarin and other dyes. Anthracene is colorless but exhibits a blue (400–500 nm peak) fluorescence under ultraviolet radiation.
The Friedel–Crafts reactions are a set of reactions developed by Charles Friedel and James Crafts in 1877 to attach substituents to an aromatic ring. Friedel–Crafts reactions are of two main types: alkylation reactions and acylation reactions. Both proceed by electrophilic aromatic substitution.
Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen atom. Chemical compounds containing such rings are also referred to as furans.
Nitrobenzene is an aromatic nitro compound and the simplest of the nitrobenzenes, with the chemical formula C6H5NO2. It is a water-insoluble pale yellow oil with an almond-like odor. It freezes to give greenish-yellow crystals. It is produced on a large scale from benzene as a precursor to aniline. In the laboratory, it is occasionally used as a solvent, especially for electrophilic reagents.
In organic chemistry, nitration is a general class of chemical processes for the introduction of a nitro group into an organic compound. The term also is applied incorrectly to the different process of forming nitrate esters between alcohols and nitric acid. The difference between the resulting molecular structures of nitro compounds and nitrates is that the nitrogen atom in nitro compounds is directly bonded to a non-oxygen atom, whereas in nitrate esters, the nitrogen is bonded to an oxygen atom that in turn usually is bonded to a carbon atom.
Triphenylene is an organic compound with the formula (C6H4)3. A flat polycyclic aromatic hydrocarbon (PAH), it consists of four fused benzene rings. Triphenylene has delocalized 18-π-electron systems based on a planar structure, corresponding to the symmetry group D3h. It is a white or colorless solid.
Aromatization is a chemical reaction in which an aromatic system is formed from a single nonaromatic precursor. Typically aromatization is achieved by dehydrogenation of existing cyclic compounds, illustrated by the conversion of cyclohexane into benzene. Aromatization includes the formation of heterocyclic systems.
In-Methylcyclophanes are organic compounds and members of a larger family of cyclophanes. These compounds are used to study how chemical bonds in molecules adapt to strain. In-methylcyclophanes in particular have a methyl group in proximity to a benzene ring. This is only possible when both methyl group and ring are attached to the same rigid scaffold. In one In-methylcyclophane molecule this is accomplished with a triptycene frame.
Organoselenium chemistry is the science exploring the properties and reactivity of organoselenium compounds, chemical compounds containing carbon-to-selenium chemical bonds. Selenium belongs with oxygen and sulfur to the group 16 elements or chalcogens, and similarities in chemistry are to be expected. Organoselenium compounds are found at trace levels in ambient waters, soils and sediments.
The Blanc chloromethylation is the chemical reaction of aromatic rings with formaldehyde and hydrogen chloride to form chloromethyl arenes. The reaction is catalyzed by Lewis acids such as zinc chloride. The reaction was discovered by Gustave Louis Blanc (1872-1927) in 1923.
Carbazole is an aromatic heterocyclic organic compound. It has a tricyclic structure, consisting of two six-membered benzene rings fused on either side of a five-membered nitrogen-containing ring. The compound's structure is based on the indole structure, but in which a second benzene ring is fused onto the five-membered ring at the 2–3 position of indole.
Unlike its lighter congeners, the halogen iodine forms a number of stable organic compounds, in which iodine exhibits higher formal oxidation states than -1 or coordination number exceeding 1. These are the hypervalent organoiodines, often called iodanes after the IUPAC rule used to name them.
The Quelet reaction is an organic coupling reaction in which a phenolic ether reacts with an aliphatic aldehyde to generate an α-chloroalkyl derivative. The Quelet reaction is an example of a larger class of reaction, electrophilic aromatic substitution. The reaction is named after its creator R. Quelet, who first reported the reaction in 1932, and is similar to the Blanc chloromethylation process.
Trifluoroperacetic acid is an organofluorine compound, the peroxy acid analog of trifluoroacetic acid, with the condensed structural formula CF
3COOOH. It is a strong oxidizing agent for organic oxidation reactions, such as in Baeyer–Villiger oxidations of ketones. It is the most reactive of the organic peroxy acids, allowing it to successfully oxidise relatively unreactive alkenes to epoxides where other peroxy acids are ineffective. It can also oxidise the chalcogens in some functional groups, such as by transforming selenoethers to selones. It is a potentially explosive material and is not commercially available, but it can be quickly prepared as needed. Its use as a laboratory reagent was pioneered and developed by William D. Emmons.
Diphenic acid, also known as Dibenzoic acid, is an organic compound with the formula (C6H4CO2H)2. It is the most studied of several isomeric dicarboxylic acids of biphenyl. It is a white solid that can be prepared in the laboratory from anthranilic acid via the diazonium salt. It is the product of the microbial action on phenanthrene.