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Cyclohexanehexone
Cyclohexanehexone, also known as hexaketocyclohexane and triquinoyl, is an organic compound with formula , the sixfold ketone of cyclohexane. It is an oxide of carbon (an oxocarbon), a hexamer of carbon monoxide. The compound is expected to be highly unstable, unlike the cyclohexanehexathione analog, and as of 1999 had only been observed as an ionized fragment during mass spectrometry studies. Related compounds Cyclohexanehexone can be viewed as the neutral counterpart of the rhodizonate anion . The singly charged anion has been detected in mass spectrometry experiments, formed by oligomerization of carbon monoxide through the formation of molybdenum carbonyls. According to X-ray diffraction analysis, the reagent traded under the name "cyclohexanehexone octahydrate" or equivalent names is actually dodecahydroxycyclohexane dihydrate—the geminal diol derivative of the six ketone groups with an additional two molecules of water—a solid that decomposes at 95 ° ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dodecahydroxycyclohexane
Dodecahydroxycyclohexane is an organic compound with molecular formula or or . It is a sixfold geminal diol with a cyclohexane backbone and can be regarded as a sixfold hydrate of cyclohexanehexone (). Dihydrate The dihydrate can be crystallized from methanol as colorless plates or prisms, that decomposes at about 100 °C. This compound was synthesized by J. Lerch in 1862 by oxidation of benzenehexol or tetrahydroxy-''p''-benzoquinone and characterized by R. Nietzki and others in 1885, although the product was for a long time assumed to be hexaketocyclohexane with water of crystallization (). Indeed, this product is still commonly marketed as cyclohexanehexone octahydrate, hexaketocyclohexane octahydrate, triquinoyl octahydrate and similar names. Its true nature was suspected since the 1950s or earlier, but was confirmed by X-ray diffraction analysis only in 2005. See also *Decahydroxycyclopentane Decahydroxycyclopentane is an organic compound with formula or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxocarbons
In chemistry, an oxocarbon or oxide of carbon is a chemical compound consisting only of carbon and oxygen. The simplest and most common oxocarbons are carbon monoxide (CO) and carbon dioxide (). Many other stable (practically if not thermodynamically) or metastable oxides of carbon are known, but they are rarely encountered, such as carbon suboxide ( or ) and mellitic anhydride (). Many other oxides are known today, most of them synthesized since the 1960s. Some of these new oxides are stable at room temperature. Some are metastable or stable only at very low temperatures, but decompose to simpler oxocarbons when warmed. Many are inherently unstable and can be observed only momentarily as intermediates in chemical reactions or are so reactive that they exist only in gas phase or have only been detected by matrix isolation. Graphene oxide and other stable polymeric carbon oxides with unbounded molecular structures exist. Overview Carbon dioxide (CO2) occurs widely in nature, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxocarbon
In chemistry, an oxocarbon or oxide of carbon is a chemical compound consisting only of carbon and oxygen. The simplest and most common oxocarbons are carbon monoxide (CO) and carbon dioxide (). Many other stable (practically if not thermodynamically) or metastable oxides of carbon are known, but they are rarely encountered, such as carbon suboxide ( or ) and mellitic anhydride (). Many other oxides are known today, most of them synthesized since the 1960s. Some of these new oxides are stable at room temperature. Some are metastable or stable only at very low temperatures, but decompose to simpler oxocarbons when warmed. Many are inherently unstable and can be observed only momentarily as intermediates in chemical reactions or are so reactive that they exist only in gas phase or have only been detected by matrix isolation. Graphene oxide and other stable polymeric carbon oxides with unbounded molecular structures exist. Overview Carbon dioxide (CO2) occurs widely in nature, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhodizonic Acid
Rhodizonic acid is a chemical compound with formula or . It can be seen as a twofold enol and fourfold ketone of cyclohexene, more precisely 5,6-dihydroxycyclohex-5-ene-1,2,3,4-tetrone. Rhodizonic acid is usually obtained in the form of a dihydrate . The latter is actually 2,3,5,5,6,6-hexahydroxycyclohex-2-ene-1,4-dione, where two of the original ketone groups are replaced by two pairs of geminal diols. The orange to deep-red and highly hygroscopic anhydrous acid can be obtained by low-pressure sublimation of the dihydrate. Like many other enols, rhodizonic acid can lose the hydrogen cations H+ from the hydroxyls (p''K''a1 = , p''K''a2 = at 25 °C), yielding the hydrogenrhodizonate anion and the rhodizonate anion . The latter is aromatic and symmetric, as the double bond and the negative charges are delocalized and evenly distributed over the six CO units. Rhodizonates tend to have various shades of red, from yellowish to purplish. Rhodizonic acid has been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclohexanehexathione
Cyclohexanehexathione is a cyclic covalent compound consisting of a six-carbon ring with a sulfur bonded to each. It has been generated by neutralization of its monoanion () in a mass spectrometer. This compound is the thioketone analog of cyclohexanehexone; that oxygen variant is expected to be substantially less stable. Synthesis of by photolysis or pyrolysis to extrude three equivalents of carbon monoxide from a precursor containing adjacent pairs of sulfurs as cyclic dithiocarbonate units gave what is more likely a different valence isomer, as various dithiete-containing structures are predicted to be more stable than the hexathione form. : This theoretical analysis of the various isomers and experimental analysis of this reaction cast doubt on whether the mass spectrometric approach really did produce the hexathione isomer as originally claimed. The increased stability of dithietes as compared to dioxetane A dioxetane or dioxacyclobutane is an organic compound with fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Monoxide
Carbon monoxide (chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the simplest molecule of the oxocarbon family. In coordination complexes the carbon monoxide ligand is called carbonyl. It is a key ingredient in many processes in industrial chemistry. The most common source of carbon monoxide is the partial combustion of carbon-containing compounds, when insufficient oxygen or heat is present to produce carbon dioxide. There are also numerous environmental and biological sources that generate and emit a significant amount of carbon monoxide. It is important in the production of many compounds, including drugs, fragrances, and fuels. Upon emission into the atmosphere, carbon monoxide affects several processes that contribute to climate change. Carbon monoxide has important biological roles across phylogenetic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclohexanehexathione
Cyclohexanehexathione is a cyclic covalent compound consisting of a six-carbon ring with a sulfur bonded to each. It has been generated by neutralization of its monoanion () in a mass spectrometer. This compound is the thioketone analog of cyclohexanehexone; that oxygen variant is expected to be substantially less stable. Synthesis of by photolysis or pyrolysis to extrude three equivalents of carbon monoxide from a precursor containing adjacent pairs of sulfurs as cyclic dithiocarbonate units gave what is more likely a different valence isomer, as various dithiete-containing structures are predicted to be more stable than the hexathione form. : This theoretical analysis of the various isomers and experimental analysis of this reaction cast doubt on whether the mass spectrometric approach really did produce the hexathione isomer as originally claimed. The increased stability of dithietes as compared to dioxetane A dioxetane or dioxacyclobutane is an organic compound with fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon
Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with other atoms when it forms chemical compounds or molecules. Description The combining capacity, or affinity of an ...—its atom making four electrons available to form covalent bond, covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes up only about 0.025 percent of Earth's crust. Three Isotopes of carbon, isotopes occur naturally, Carbon-12, C and Carbon-13, C being stable, while Carbon-14, C is a radionuclide, decaying with a half-life of about 5,730 years. Carbon is one of the Timeline of chemical element discoveries#Ancient discoveries, few elements known since antiquity. Carbon is the 15th Abundance of elements in Earth's crust, most abundant element in the Earth's crust, and the Abundance of the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypothetical Chemical Compounds
A hypothesis (plural hypotheses) is a proposed explanation for a phenomenon. For a hypothesis to be a scientific hypothesis, the scientific method requires that one can test it. Scientists generally base scientific hypotheses on previous observations that cannot satisfactorily be explained with the available scientific theories. Even though the words "hypothesis" and "theory" are often used interchangeably, a scientific hypothesis is not the same as a scientific theory. A working hypothesis is a provisionally accepted hypothesis proposed for further research in a process beginning with an educated guess or thought. A different meaning of the term ''hypothesis'' is used in formal logic, to denote the antecedent of a proposition; thus in the proposition "If ''P'', then ''Q''", ''P'' denotes the hypothesis (or antecedent); ''Q'' can be called a consequent. ''P'' is the assumption in a (possibly counterfactual) ''What If'' question. The adjective ''hypothetical'', meaning "havin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William J
William is a male given name of Germanic origin.Hanks, Hardcastle and Hodges, ''Oxford Dictionary of First Names'', Oxford University Press, 2nd edition, , p. 276. It became very popular in the English language after the Norman conquest of England in 1066,All Things William"Meaning & Origin of the Name"/ref> and remained so throughout the Middle Ages and into the modern era. It is sometimes abbreviated "Wm." Shortened familiar versions in English include Will, Wills, Willy, Willie, Bill, and Billy. A common Irish form is Liam. Scottish diminutives include Wull, Willie or Wullie (as in Oor Wullie or the play ''Douglas''). Female forms are Willa, Willemina, Wilma and Wilhelmina. Etymology William is related to the given name ''Wilhelm'' (cf. Proto-Germanic ᚹᛁᛚᛃᚨᚺᛖᛚᛗᚨᛉ, ''*Wiljahelmaz'' > German ''Wilhelm'' and Old Norse ᚢᛁᛚᛋᛅᚼᛅᛚᛘᛅᛋ, ''Vilhjálmr''). By regular sound changes, the native, inherited English form of the name shoul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclic Ketones
In organic chemistry, a ketone is a functional group with the structure R–C(=O)–R', where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group –C(=O)– (which contains a carbon-oxygen double bond C=O). The simplest ketone is acetone (where R and R' is methyl), with the formula . Many ketones are of great importance in biology and in industry. Examples include many sugars (ketoses), many steroids (e.g., testosterone), and the solvent acetone. Nomenclature and etymology The word ''ketone'' is derived from ''Aketon'', an old German word for ''acetone''. According to the rules of IUPAC nomenclature, ketone names are derived by changing the suffix ''-ane'' of the parent alkane to ''-anone''. Typically, the position of the carbonyl group is denoted by a number, but traditional nonsystematic names are still generally used for the most important ketones, for example acetone and benzophenone. These nonsystematic names are considered reta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethylenetetracarboxylic Dianhydride
Ethylenetetracarboxylic dianhydride is a chemical compound with formula , that can be seen as the twofold anhydride of ethylenetetracarboxylic acid . It has a bicyclic molecular structure consisting of two maleic anhydride rings fused by their respective alkene units. It is a pale yellow oily liquid, soluble in dichloromethane and chloroform. The compound and its reactions were first reported in 1967. Jürgen Sauer, Barbara Schröder, Richard Wiemer (1967), ''Eine Studie der Diels-Alder-Reaktion, VI. Kinetischer Nachweis des Moleküls C6O6 (Dianhydrid der Äthylentetracarbonsäure)''. Chemische Berichte Volume 100 Issue 1, Pages 306-314 Jürgen Sauer, Barbara Schröder, Albrecht Mielert (1967), ''Eine Studie der Diels-Alder-Reaktion, VII. Reaktionen des Dianhydrids der Äthylentetracarbonsäure (C6O6)''. Chemische Berichte Volume 100 Issue 1, Pages 315-322 More recently developed reactions for its synthesis include pyrolysis of ethylenetetracarboxylic acid John M. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
