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Names | |
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Preferred IUPAC name Tetracene [1] | |
Other names Naphthacene Benz[b]anthracene 2,3-Benzanthracene Tetracyclo[8.8.0.03,8.012,17]octadeca-1,3,5,7,9,11,13,15,17-nonaene | |
Identifiers | |
3D model (JSmol) | |
ChEBI | |
ChemSpider | |
ECHA InfoCard | 100.001.945 |
PubChem CID | |
UNII | |
CompTox Dashboard (EPA) | |
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Properties | |
C18H12 | |
Molar mass | 228.29 g/mol |
Appearance | Yellow to orange solid |
Melting point | 357 °C (675 °F; 630 K) |
Boiling point | 436.7 °C (818.1 °F; 709.8 K) |
Insoluble | |
-168.0·10−6 cm3/mol | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Tetracene, also called naphthacene, is a polycyclic aromatic hydrocarbon. It has the appearance of a pale orange powder. Tetracene is the four-ringed member of the series of acenes.
Tetracene is a molecular organic semiconductor, used in organic field-effect transistors (OFETs) and organic light-emitting diodes (OLEDs). Tetracene can be used as a gain medium in dye lasers as a sensitiser in chemoluminescence. Napthacene is the main component of the tetracycline class of antibiotics.
In 1884, W. Roser attempted to synthesize a compound called "Aethindiphtalyls" (literally "ethyne diphthalyl") [2] by heating 3 parts of phthalic anhydride, 3 parts of succinic acid and one part of sodium acetate according to Siegmund Gabriel's procedure. [3] And then he found that there was a brick-red byproduct was produced in a large amount in the reaction, which was called "Isoäthindiphtalid" (literally "Isoethyne diphthalide") and founded to be an isomer of "Aethindiphtalyls". In 1898, Gabriel and Ernst Leupold did a study on the byproduct and confirmed it was a new class of compound containing 4 rings. [4]
In the same document, Gabriel and Leupold reported their synthesis of tetracene by condensating two moles of phthalic anhydride with a mole of succinic acid into a quinone then reduced with zinc dust. [5] [6] They named in naphthacene, likely as portmanteau of naphthalene and anthracene. Modern nomenclature for polyacenes, including tetracene, was introduced by Erich Clar in 1939. [7] [8] Clar also developed a new route to synthesize tetracene from the Friedel-Crafts acrylation between phthalic anhydride and tetralin catalyzed by AlCl3, ZnCl2 and NaCl involving Clemmensen reduction, forming 5,12-dihydrotetracene then dehydrogenated by chloranil to form tetracene. [9]
German physicist Jan Hendrik Schön claimed to have developed an electrically pumped laser based on tetracene during his time at Bell Labs (1997–2002). However, his results could not be reproduced, and this is considered to be a scientific fraud. [10]
In May 2007, Japanese researchers from Tohoku University and Osaka University reported an ambipolar light-emitting transistor made of a single tetracene crystal. [11] Ambipolar means that the electric charge is transported by both positively charged holes and negatively charged electrons.
In 2024, it was used to produce lower-energy excitations in solar cells in a process known as singlet fission. An interface layer between tetracene and silicon transfers them into the silicon layer, where most of their energy can be converted into electricity. [12]
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.
Phthalic anhydride is the organic compound with the formula C6H4(CO)2O. It is the anhydride of phthalic acid. Phthalic anhydride is a principal commercial form of phthalic acid. It was the first anhydride of a dicarboxylic acid to be used commercially. This white solid is an important industrial chemical, especially for the large-scale production of plasticizers for plastics. In 2000, the worldwide production volume was estimated to be about 3 million tonnes per year.
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.
A Polycyclic aromatic hydrocarbon (PAH) is a class of organic compounds that is composed of multiple aromatic rings. Most are produced by the incomplete combustion of organic matter— by engine exhaust fumes, tobacco, incinerators, in roasted meats and cereals, or when biomass burns at lower temperatures as in forest fires. 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 also found in fossil fuel deposits such as coal and in petroleum. Exposure to PAHs can lead to different types of cancer, to fetal development complications, and to cardiovascular issues.
Anthraquinone, also called anthracenedione or dioxoanthracene, is an aromatic organic compound with formula C
14H
8O
2. Several isomers exist but these terms usually refer to 9,10-anthraquinone wherein the keto groups are located on the central ring. It is used as a digester additive to wood pulp for papermaking. Many anthraquinone derivatives are generated by organisms or synthesised industrially for use as dyes, pharmaceuticals, and catalysts. Anthraquinone is a yellow, highly crystalline solid, poorly soluble in water but soluble in hot organic solvents. It is almost completely insoluble in ethanol near room temperature but 2.25 g will dissolve in 100 g of boiling ethanol. It is found in nature as the rare mineral hoelite.
The Pummerer rearrangement is an organic reaction whereby an alkyl sulfoxide rearranges to an α-acyloxy–thioether (monothioacetal-ester) in the presence of acetic anhydride.
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.
Clemmensen reduction is a chemical reaction described as a reduction of ketones or aldehydes to alkanes using zinc amalgam and concentrated hydrochloric acid (HCl). This reaction is named after Erik Christian Clemmensen, a Danish-American chemist.
Pentacene is a polycyclic aromatic hydrocarbon consisting of five linearly-fused benzene rings. This highly conjugated compound is an organic semiconductor. The compound generates excitons upon absorption of ultra-violet (UV) or visible light; this makes it very sensitive to oxidation. For this reason, this compound, which is a purple powder, slowly degrades upon exposure to air and light.
Hexacene is an aromatic compound consisting of six linearly-fused benzene rings. It is a blue-green, air-stable solid with low solubility.
In organic and physical organic chemistry, Clar's rule is an empirical rule that relates the chemical stability of a molecule to its aromaticity. It was introduced in 1972 by the Austrian organic chemist Erich Clar in his book The Aromatic Sextet. The rule states that given a polycyclic aromatic hydrocarbon, the resonance structure most important to characterize its properties is that with the largest number of aromatic π-sextets i.e. benzene-like moieties.
Basketane is a polycyclic alkane with the chemical formula C10H12. The name is taken from its structural similarity to a basket shape. Basketane was first synthesized in 1966, independently by Masamune and Dauben and Whalen. A patent application published in 1988 used basketane, which is a hydrocarbon, as a source material in doping thin diamond layers because of the molecule's high vapor pressure, carbon ring structure, and fewer hydrogen-to-carbon bond ratio.
Phthalonitrile is an organic compound with the formula C6H4(CN)2, which is an off-white crystal solid at room temperature. It is a derivative of benzene, containing two adjacent nitrile groups. The compound has low solubility in water but is soluble in common organic solvents. The compound is used as a precursor to phthalocyanine and other pigments, fluorescent brighteners, and photographic sensitizers.
Organosodium chemistry is the chemistry of organometallic compounds containing a carbon to sodium chemical bond. The application of organosodium compounds in chemistry is limited in part due to competition from organolithium compounds, which are commercially available and exhibit more convenient reactivity.
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.
Friedrich Hermann Leuchs was a German chemist.
Kekulene is a polycyclic aromatic hydrocarbon which consists of 12 fused benzene rings arranged in a circle. It is therefore classified as a [12]-circulene with the chemical formula C48H24. It was first synthesized in 1978, and was named in honor of August Kekulé, the discoverer of the structure of the benzene molecule.
Zethrene (dibenzo[de,mn]naphthacene) is a polycyclic aromatic hydrocarbon consisting of two phenalene units fused together. According to Clar's rule, the two exterior naphthalene units are truly aromatic and the two central double bonds are not aromatic at all. For this reason the compound is of some interest to academic research. Zethrene has a deep-red color and it is light sensitive - complete decomposition under a sunlight lamp occurs within 12 hours. The melting point is 262 °C.
Roland Heinrich Scholl was a Swiss chemist who taught at various European universities. Among his most notable achievements are the synthesis of coronene, the co-development of the Bally-Scholl synthesis, and various discoveries about polycyclic aromatic hydrocarbons.
Boraacenes are polycyclic aromatic hydrocarbons containing at least one boron atom. Structurally, they are related to acenes, linearly fused benzene rings. However, the boron atom is electron deficient and may act as a Lewis Acid when compared to carbon. This results in slightly less negative charge within the ring, smaller HOMO-LUMO gaps, as well as differences in redox chemistry when compared to their acene analogues. When incorporated into acenes, Boron maintains the planarity and aromaticity of carbon acenes, while adding an empty p-orbital, which can be utilized for the fine tuning of organic semiconductor band gaps. Due to this empty p orbital, however, it is also highly reactive when exposed to nucleophiles like water or normal atmosphere, as it will readily be attacked by oxygen, which must be addressed to maintain its stability.