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Names | |
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Preferred IUPAC name 4-[Bis(4-hydroxyphenyl)methylidene]cyclohexa-2,5-dien-1-one | |
Other names Aurin, corallin, p-rosolic acid, C.I. 43800 | |
Identifiers | |
3D model (JSmol) | |
2055205 | |
ChEMBL | |
ChemSpider | |
ECHA InfoCard | 100.009.129 |
EC Number |
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PubChem CID | |
UNII | |
CompTox Dashboard (EPA) | |
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Properties | |
C19H14O3 | |
Molar mass | 290.318 g·mol−1 |
Appearance | see text |
Density | 1.283 g/cm3 |
Melting point | 308 °C (586 °F; 581 K) (decomposes) |
Insoluble | |
UV-vis (λmax) | 482 nm [1] |
-161.4·10−6 cm3/mol | |
Hazards | |
GHS labelling: | |
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Danger | |
H315, H319, H335 [1] | |
P261, P305+P351+P338 [1] | |
NFPA 704 (fire diamond) | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Aurin (C.I. 43800), sometimes named rosolic acid or corallin is an organic compound, forming yellowish or deep-red crystals with greenish metallic luster. It is practically insoluble in water, freely soluble in alcohol. It is soluble in strong acids to form yellow solution, or in aqueous alkalis to form carmine red solutions.
Aurin(pH indicator) | ||
below pH 5.0 | above pH 6.8 | |
5.0 | ⇌ | 6.8 |
Due to this behaviour it can be used as pH indicator with pH transition range 5.0 - 6.8. It is used as an intermediate in manufacturing of dyes.
Aurin was first prepared in 1834 by the German chemist Friedlieb Ferdinand Runge, who obtained it by distilling coal tar. He named it Rosölsäure or Rosaölsäure (red oil acid). [2] [3] In 1861, the German chemists Hermann Kolbe and Rudolf Schmitt presented the synthesis of aurin by heating oxalic acid and creosote (which contains phenol) in the presence of concentrated sulfuric acid. [4] (Gradually, chemists realized that commercial aurin was not a pure compound, but was actually a mixture of similar compounds. [5] [6] )
Aurin is formed by heating of phenol and oxalic acid in concentrated sulfuric acid.
Aurin may cause eye, skin, and respiratory tract irritation. Ingestion and inhalation should be avoided.
Aurin was reported to have endocrine disruptor chemical (EDC) properties. [7] : 149
Adolph Wilhelm Hermann Kolbe was a German chemist and academic, and a major contributor to the birth of modern organic chemistry. He was a professor at Marburg and Leipzig. Kolbe was the first to apply the term synthesis in a chemical context, and contributed to the philosophical demise of vitalism through synthesis of the organic substance acetic acid from carbon disulfide, and also contributed to the development of structural theory. This was done via modifications to the idea of "radicals" and accurate prediction of the existence of secondary and tertiary alcohols, and to the emerging array of organic reactions through his Kolbe electrolysis of carboxylate salts, the Kolbe-Schmitt reaction in the preparation of aspirin and the Kolbe nitrile synthesis. After studies with Wöhler and Bunsen, Kolbe was involved with the early internationalization of chemistry through work in London. He was elected to the Royal Swedish Academy of Sciences, and won the Royal Society of London's Davy Medal in the year of his death. Despite these accomplishments and his training important members of the next generation of chemists, Kolbe is best remembered for editing the Journal für Praktische Chemie for more than a decade, in which his vituperative essays on Kekulé's structure of benzene, van't Hoff's theory on the origin of chirality and Baeyer's reforms of nomenclature were personally critical and linguistically violent. Kolbe died of a heart attack in Leipzig at age 66, six years after the death of his wife, Charlotte.
Phenol is an aromatic organic compound with the molecular formula C6H5OH. It is a white crystalline solid that is volatile. The molecule consists of a phenyl group bonded to a hydroxy group. Mildly acidic, it requires careful handling because it can cause chemical burns.
Aniline is an organic compound with the formula C6H5NH2. Consisting of a phenyl group attached to an amino group, aniline is the simplest aromatic amine. It is an industrially significant commodity chemical, as well as a versatile starting material for fine chemical synthesis. Its main use is in the manufacture of precursors to polyurethane, dyes, and other industrial chemicals. Like most volatile amines, it has the odor of rotten fish. It ignites readily, burning with a smoky flame characteristic of aromatic compounds. It is toxic to humans.
Gerardus Johannes Mulder or Gerrit Jan Mulder was a Dutch organic and analytical chemist.
Resorcinol (or resorcin) is a phenolic compound. It is an organic compound with the formula C6H4(OH)2. It is one of three isomeric benzenediols, the 1,3-isomer (or meta-isomer). Resorcinol crystallizes from benzene as colorless needles that are readily soluble in water, alcohol, and ether, but insoluble in chloroform and carbon disulfide.
Ferdinand Reich was a German chemist who co-discovered indium in 1863 with Hieronymous Theodor Richter.
The Kolbe–Schmitt reaction or Kolbe process is a carboxylation chemical reaction that proceeds by treating phenol with sodium hydroxide to form sodium phenoxide, then heating sodium phenoxide with carbon dioxide under pressure, then treating the product with sulfuric acid. The final product is an aromatic hydroxy acid which is also known as salicylic acid.
Cyclohexanone is the organic compound with the formula (CH2)5CO. The molecule consists of six-carbon cyclic molecule with a ketone functional group. This colorless oily liquid has a sweet odor reminiscent of benzaldehyde. Over time, samples of cyclohexanone assume a pale yellow color.
Pelopium was the proposed name for a new element found by the chemist Heinrich Rose in 1845. The name derived from the Greek king and later god Pelops, son of Tantalus. During the analysis of the mineral tantalite, he concluded that it does contain an element similar to niobium and tantalum. The similar reactivity of niobium and tantalum complicated preparation of pure samples and therefore several new elements were proposed, which were later found to be mixtures of niobium and tantalum.
Biuret is a chemical compound with the chemical formula HN(CONH2)2. It is a white solid that is soluble in hot water. A variety of organic derivatives are known. The term "biuret" also describes a family of organic compounds with the chemical formula R1R2N−C(=O)−N(R3)−C(=O)−NR4R5, where R1, R2, R3, R4 and R5 are hydrogen, organyl or other groups. Also known as carbamylurea, it results from the condensation of two equivalents of urea. It is a common undesirable impurity in urea-based fertilizers, as biuret is toxic to plants.
Phenyl salicylate, or salol, is the organic compound with the formula C6H5O2C6H4OH. It is a white solid. It is occasionally used in sunscreens and as an antiseptic.
Johann Gottlieb was an Austrian chemist who first synthesized Propionic acid. He is also known for describing and naming Paramylon.
Mellitic anhydride, the anhydride of mellitic acid, is an organic compound with the formula C12O9.
Ilmenium was the proposed name for a new element found by the chemist R. Hermann in 1847. During the analysis of the mineral samarskite, he concluded that it does contain an element similar to niobium and tantalum. The similar reactivity of niobium and tantalum complicated preparation of pure samples of the metals and therefore several new elements were proposed, which were later found to be mixtures of niobium and tantalum.
Dianium was the proposed name for a new element found by the mineralogist and poet Wolfgang Franz von Kobell in 1860. The name derived from the Roman goddess Diana. During the analysis of the mineral tantalite and niobite, he concluded that it does contain an element similar to niobium and tantalum. The symbol was Di.
Wasium was the suggested name of a chemical element found by J. F. Bahr. The name was derived from the House of Vasa the Royal House of Sweden.
The Borsche–Drechsel cyclization is a chemical reaction used to synthesize tetrahydrocarbazoles by the acid-catalyzed cyclization of cyclohexanone arylhydrazones. The reaction was first described by Edmund Drechsel in 1888 and by Walther Borsche in 1908.
Radical theory is an obsolete scientific theory in chemistry describing the structure of organic compounds. The theory was pioneered by Justus von Liebig, Friedrich Wöhler and Auguste Laurent around 1830 and is not related to the modern understanding of free radicals. In this theory, organic compounds were thought to exist as combinations of radicals that could be exchanged in chemical reactions just as chemical elements could be interchanged in inorganic compounds.
The Journal für praktische Chemie was a German-language scientific journal for chemistry. The journal was founded in 1828 by Otto Linné Erdmann (1804–1869) as the Journal für technische und ökonomische Chemie, the oldest chemical trade journal in Germany. From 1828 to 1869 Erdmann was the editor, along with Franz Wilhelm Schweigger-Seidel, Richard Felix Marchand, and Gustav Werther. From 1870 to 1884 Hermann Kolbe was the editor-in-chief. From 1879 to 1884 Ernst von Meyer worked as co-editor under Kolbe and became editor-in-chief upon Kolbe's death in 1884 and continued in that capacity until his own death in 1916. Beginning in 1917 the journal was edited by Julius Bredt, Theodor Curtius, Karl Elbs, Otto Fischer (1852–1932), Fritz Foerster, and Berthold Rassow with August Darapsky as editor-in-chief. Beginning in 1953 the Journal für praktische Chemie was published by the Chemische Gesellschaft der DDR.
Karl Ludwig Reimer was a German chemist and industrialist. He's responsible for the cheap synthesis of the chemical compound Vanillin, having discovered the Reimer-Tiemann Reaction.