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:
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.
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. PAHs are uncharged, non-polar and planar. Many are colorless. Many of them are found in coal and in oil deposits, and are also produced by the incomplete combustion of organic matter—for example, in engines and incinerators or when biomass burns in forest fires.
Benzo[a]pyrene (BaP or B[a]P) is a polycyclic aromatic hydrocarbon and the result of incomplete combustion of organic matter at temperatures between 300 °C (572 °F) and 600 °C (1,112 °F). The ubiquitous compound can be found in coal tar, tobacco smoke and many foods, especially grilled meats. The substance with the formula C20H12 is one of the benzopyrenes, formed by a benzene ring fused to pyrene. Its diol epoxide metabolites (more commonly known as BPDE) react with and bind to DNA, resulting in mutations and eventually cancer. It is listed as a Group 1 carcinogen by the IARC. In the 18th century a scrotal cancer of chimney sweepers, the chimney sweeps' carcinoma, was already known to be connected to soot.
Perylene or perilene is a polycyclic aromatic hydrocarbon with the chemical formula C20H12, occurring as a brown solid. It or its derivatives may be carcinogenic, and it is considered to be a hazardous pollutant. In cell membrane cytochemistry, perylene is used as a fluorescent lipid probe. It is the parent compound of a class of rylene dyes.
9,10-Bis(phenylethynyl)anthracene (BPEA) is an aromatic hydrocarbon with the chemical formula is C30H18. It displays strong fluorescence and is used as a chemiluminescent fluorophore with high quantum efficiency.
Fluoranthene is a polycyclic aromatic hydrocarbon (PAH). The molecule can be viewed as the fusion of naphthalene and benzene unit connected by a five-membered ring. Although samples are often pale yellow, the compound is colorless. It is soluble in nonpolar organic solvents. It is a member of the class of PAHs known as non-alternant PAHs because it has rings other than those with six carbon atoms. It is a structural isomer of the alternant PAH pyrene. It is not as thermodynamically stable as pyrene. Its name is derived from its fluorescence under UV light.
In the field of organic chemistry, a polycyclic compound is an organic compound featuring several closed rings of atoms, primarily carbon. These ring substructures include cycloalkanes, aromatics, and other ring types. They come in sizes of three atoms and upward, and in combinations of linkages that include tethering, fusing, links via a single atom, bridged compounds, and longifolene. Though poly- literally means "many", there is some latitude in determining how many rings are required to be considered polycyclic; many smaller rings are described by specific prefixes, and so while it can refer to these, the title term is used with most specificity when these alternative names and prefixes are unavailable.
Mycobacterium vanbaalenii is a rapidly growing mycobacterium that can use polycyclic aromatic hydrocarbons. It was first isolated from petroleum-contaminated estuarine sediments and has been shown by 16S rRNA gene sequencing to be closely related to Mycobacterium aurum and Mycobacterium vaccae. M. vanbaalenii has potential use in the bioremediation of polycyclic aromatic hydrocarbon contaminated environmental sites. Etymology: vanbaalenii of Van Baalen, in memory of Dr Chase Van Baalen, late Professor at The University of Texas Marine Science Institute, Port Aransas Marine Laboratory, Port Aransas, TX, USA.
Mycobacterium pyrenivorans is a scotochromogenic, rapidly growing mycobacterium, first isolated from an enrichment culture obtained from soil that was highly contaminated with polycyclic aromatic hydrocarbons (PAHs). The soil sample was collected on the site of a former coking plant at Ubach-Palenberg, Germany. Etymology: pyrenivorans; digesting pyrene.
A benzopyrene is an organic compound with the formula C20H12. Structurally speaking, the colorless isomers of benzopyrene are pentacyclic hydrocarbons and are fusion products of pyrene and a phenylene group. Two isomeric species of benzopyrene are benzo[a]pyrene and the less common benzo[e]pyrene. They belong to the chemical class of polycyclic aromatic hydrocarbons.
Benz[a]anthracene or benzo[a]anthracene is a polycyclic aromatic hydrocarbon with the chemical formula C18H12. It is produced during incomplete combustion of organic matter.
Benzo[j]fluoranthene (BjF) is an organic compound with the chemical formula C20H12. Classified as a polycyclic aromatic hydrocarbon (PAH), it is a colourless solid that is poorly soluble in most solvents. Impure samples can appear off white. Closely related isomeric compounds include benzo[a]fluoranthene (BaF), bendo[b]fluoranthene (BbF), benzo[e]fluoranthene (BeF), and benzo[k]fluoranthene (BkF). BjF is present in fossil fuels and is released during incomplete combustion of organic matter. It has been traced in the smoke of cigarettes, exhaust from gasoline engines, emissions from the combustion of various types of coal and emissions from oil heating, as well as an impurity in some oils such as soybean oil.
2-Chloro-9,10-diphenylanthracene is a fluorescent dye used in glow sticks for a blue-green glow. It is a chlorinated derivative of 9,10-diphenylanthracene.
9,10-Dihydroanthracene is an organic compound that is derived from the polycyclic aromatic hydrocarbon anthracene. Several isomers of dihydroanthracene are known, but the 9,10 derivative is most common. It is a colourless solid that is used as a carrier of H2 as a hydrogen-donor.
Phenacenes are a class of organic compounds consisting of fused aromatic rings. They are polycyclic aromatic hydrocarbons, related to acenes and helicenes from which they differ by the arrangement of the fused rings.
Thermal rearrangements of aromatic hydrocarbons are considered to be unimolecular reactions that directly involve the atoms of an aromatic ring structure and require no other reagent than heat. These reactions can be categorized in two major types: one that involves a complete and permanent skeletal reorganization (isomerization), and one in which the atoms are scrambled but no net change in the aromatic ring occurs (automerization). The general reaction schemes of the two types are illustrated in Figure 1.
Phenanthrenedione is a quinone derivative of a polycyclic aromatic hydrocarbon. It is an orange, water-insoluble solid.
(+)-Benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide is an organic compound with molecular formula C20H14O3. It is a metabolite and derivative of benzo[a]pyrene (found in tobacco smoke) as a result of oxidation to include hydroxyl and epoxide functionalities. (+)-Benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide binds to the N2 atom of a guanine nucleobase in DNA, distorting the double helix structure by intercalation of the pyrene moiety between base pairs through π-stacking. The carcinogenic properties of tobacco smoking are attributed in part to this compound binding and inactivating the tumor suppression ability of certain genes, leading to genetic mutations and potentially to cancer.
Rubicene is a polycyclic aromatic hydrocarbon that consists of two benzene and an anthracene. They are each linked by two carbon–carbon bonds. Dilute solutions of rubicene emit strong yellow fluorescence. It's synthesized from fluorenone by reduction of calcium or magnesium, or it can be obtained by reacting with dihalogenated diphenylanthracene as raw material. It can also be obtained by reacting 9,10-diphenylanthracene and 3 parts of DDQ in dichloromethane in the presence of triflic acid.
