Tetracene, also called naphthacene, is a

polycyclic aromatic hydrocarbon A Polycyclic aromatic hydrocarbon (PAH) is any member of a class of organic compounds that is composed of multiple fused aromatic rings. Most are produced by the incomplete combustion of organic matter— by engine exhaust fumes, tobacco, incine ...

. It has the appearance of a pale orange powder. Tetracene is the four-ringed member of the series of

acene In organic chemistry, the acenes or polyacenes are a class of organic compounds and polycyclic aromatic hydrocarbons made up of benzene () rings which have been linearly fused. They follow the general molecular formula . The larger represent ...

s. Tetracene is a molecular

organic semiconductor Organic semiconductors are solids whose building blocks are pi-bonded molecules or polymers made up by carbon and hydrogen atoms and – at times – heteroatoms such as nitrogen, sulfur and oxygen. They exist in the form of molecular crystals o ...

, used in organic field-effect transistors (OFETs) and organic light-emitting diodes (OLEDs). Tetracene can be used as a

gain medium The active laser medium (also called a gain medium or lasing medium) is the source of optical gain within a laser. The gain results from the stimulated emission of photons through electronic or molecular transitions to a lower energy state from ...

in dye lasers as a sensitiser in chemoluminescence. Napthacene is the main component of the tetracycline class of antibiotics.

History and synthesis

In 1884, W. Roser attempted to synthesize a compound called "Aethindiphtalyls" (literally "ethyne diphthalyl") by heating 3 parts of

phthalic anhydride 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 commer ...

, 3 parts of

succinic acid Succinic acid () is a dicarboxylic acid with the chemical formula (CH2)2(CO2H)2. In living organisms, succinic acid takes the form of an anion, succinate, which has multiple biological roles as a metabolic intermediate being converted into fum ...

and one part of

sodium acetate Sodium acetate, CH3COONa, also abbreviated Sodium, NaOxygen, OAcetyl, Ac, is the sodium Salt (chemistry), salt of acetic acid. This salt is colorless, deliquescent, and hygroscopy, hygroscopic. Applications Biotechnological Sodium acetate is u ...

according to

Siegmund Gabriel Siegmund Gabriel (7 November 1851 – 22 March 1924) was a German chemist. Scientific career Siegmund Gabriel began studying chemistry at the University of Berlin in 1871. He continued his studies at the University of Heidelberg in 1872 wi ...

's procedure. And then he found that there was a brick-red byproduct was produced in a large amount in the reaction, which was called "Isoäthindiphtalid" ("Isoethyne diphthalide") and founded to be an isomer of "Aethindiphtalyls". In 1898, Gabriel and Ernst Leupold conducted a study on the byproduct and confirmed it was a new class of compound containing 4 rings. 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 The quinones are a class of organic compounds that are formally "derived from aromatic compounds benzene.html" ;"title="uch as benzene">uch as benzene or naphthalene] by conversion of an even number of –CH= groups into –C(=O)– groups with ...

then reduced with zinc dust. They named in naphthacene, likely as

portmanteau In linguistics, a blend—also known as a blend word, lexical blend, or portmanteau—is a word formed by combining the meanings, and parts of the sounds, of two or more words together.

naphthalene Naphthalene is an organic compound with formula . It is the simplest polycyclic aromatic hydrocarbon, and is a white Crystal, crystalline solid with a characteristic odor that is detectable at concentrations as low as 0.08 Parts-per notation ...

and

anthracene 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, as a scintil ...

. Modern nomenclature for polyacenes, including tetracene, was introduced by

Erich Clar Erich Clar (23 August 1902 – 27 March 1987) was a German organic chemistry, organic chemist, born in Hřensko (a village directly at the border of Germany and the Czech Republic; Czech: Hřensko, German: Herrnskretschen), who studied polycyclic a ...

in 1939. Clar also developed a new route to synthesize tetracene from the Friedel-Crafts acylation between phthalic anhydride and

tetralin Tetralin (1,2,3,4-tetrahydronaphthalene) is a hydrocarbon having the chemical formula C10H12. It is a partially hydrogenated derivative of naphthalene. It is a colorless liquid that is used as a hydrogen-donor solvent. Production Tetralin is pr ...

catalyzed by AlCl₃, ZnCl₂ and

NaCl Sodium chloride , commonly known as edible salt, is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chloride ions. It is transparent or translucent, brittle, hygroscopic, and occurs as the mineral hali ...

involving

Clemmensen reduction Clemmensen reduction is a chemical reaction described as a Redox, reduction of ketones or aldehydes to alkanes using zinc Amalgam (chemistry), amalgam and concentrated hydrochloric acid (HCl). This reaction is named after Erik Christian Clemmensen ...

, forming 5,12-dihydrotetracene then dehydrogenated by

chloranil Chloranil is a quinone with the molecular formula C6Cl4O2. Also known as tetrachloro-1,4-benzoquinone, it is a yellow solid. Like the parent benzoquinone, chloranil is a planar molecule J.-M. Lü, S. V. Rosokha, I. S. Neretin and J. K. Kochi, "Qui ...

to form tetracene. German

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

Jan Hendrik Schön claimed to have developed an electrically pumped laser based on tetracene during his time at

Bell Labs Nokia Bell Labs, commonly referred to as ''Bell Labs'', is an American industrial research and development company owned by Finnish technology company Nokia. With headquarters located in Murray Hill, New Jersey, Murray Hill, New Jersey, the compa ...

(1997–2002). However, his results could not be reproduced, and this is considered to be a scientific fraud. In May 2007, Japanese researchers from

Tohoku University is a public research university in Sendai, Miyagi, Japan. It is colloquially referred to as or . Established in 1907 as the third of the Imperial Universities, after the University of Tokyo and Kyoto University, it initially focused on sc ...

and

Osaka University The , abbreviated as UOsaka or , is a List of national universities in Japan, national research university in Osaka, Japan. The university traces its roots back to Edo period, Edo-era institutions Tekijuku (1838) and Kaitokudō, Kaitokudo (1724), ...

reported an ambipolar light-emitting transistor made of a single tetracene crystal. Ambipolar means that the

electric charge Electric charge (symbol ''q'', sometimes ''Q'') is a physical property of matter that causes it to experience a force when placed in an electromagnetic field. Electric charge can be ''positive'' or ''negative''. Like charges repel each other and ...

is transported by both positively charged

holes A hole is an opening in or through a particular medium, usually a solid body. Holes occur through natural and artificial processes, and may be useful for various purposes, or may represent a problem needing to be addressed in many fields of en ...

and negatively charged

electron The electron (, or in nuclear reactions) is a subatomic particle with a negative one elementary charge, elementary electric charge. It is a fundamental particle that comprises the ordinary matter that makes up the universe, along with up qua ...

s. In 2024, it was used to produce lower-energy excitations in solar cells in a process known as

singlet fission Singlet may refer to: * singlet state, in theoretical physics, a quantum state with zero spin * Singlet fission, in molecular photophysics * in spectroscopy, an entity appearing as a single peak; see NMR spectroscopy * in optics, a single lens elem ...

. An interface layer between tetracene and silicon transfers them into the silicon layer, where most of their energy can be converted into electricity.

Notes

References

{{Authority control Polycyclic aromatic hydrocarbons Organic semiconductors Laser gain media Tetracyclic compounds Acenes

History and synthesis

See also

Notes

References