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Fluoroantimonic Acid
Fluoroantimonic acid is a mixture of hydrogen fluoride and antimony pentafluoride, containing various cations and anions (the simplest being and ). This mixture is a superacid stronger than pure sulfuric acid, by many orders of magnitude, according to its Hammett acidity function. It even protonates some hydrocarbons to afford pentacoordinate carbocations ( carbonium ions). Like its precursor hydrogen fluoride, it attacks glass, but can be stored in containers lined with PTFE (Teflon) or PFA. Chemical composition Fluoroantimonic acid is formed by combining hydrogen fluoride and antimony pentafluoride: :SbF5 + 2 HF + H2F+ The speciation (i.e., the inventory of components) of fluoroantimonic acid is complex. Spectroscopic measurements show that fluoroantimonic acid consists of a mixture of HF-solvated protons, – (such as ). Thus, the formula "" is a convenient but oversimplified approximation of the true composition. Nevertheless, the extreme acidity of this mixt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfuryl Chloride Fluoride
Sulfuryl chloride fluoride is a chemical compound with the formula . It is a colorless, easily condensed gas. It is a tetrahedral molecule. Liquified sulfuryl chloride fluoride is employed as a solvent for highly oxidizing compounds. Preparation The laboratory-scale synthesis begins with the preparation of potassium fluorosulfite: : This salt is then chlorinated to give sulfuryl chloride fluoride : Further heating (180 °C) of potassium fluorosulfite with the sulfuryl chloride fluoride gives sulfuryl fluoride. : Alternatively, sulfuryl chloride fluoride can be prepared without using gases as starting materials by treating sulfuryl chloride with ammonium fluoride or potassium fluoride in trifluoroacetic acid Trifluoroacetic acid (TFA) is a synthetic organofluorine compound with the chemical formula CF3CO2H. It belongs to the subclass of per- and polyfluoroalkyl substances (PFASs) known as ultrashort-chain perfluoroalkyl acids (PFAAs). TFA is not .... : References { ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Wiley And Sons
John Wiley & Sons, Inc., commonly known as Wiley (), is an American multinational publishing company that focuses on academic publishing and instructional materials. The company was founded in 1807 and produces books, journals, and encyclopedias, in print and electronically, as well as online products and services, training materials, and educational materials for undergraduate, graduate, and continuing education students. History The company was established in 1807 when Charles Wiley opened a print shop in Manhattan. The company was the publisher of 19th century American literary figures like James Fenimore Cooper, Washington Irving, Herman Melville, and Edgar Allan Poe, as well as of legal, religious, and other non-fiction titles. The firm took its current name in 1865. Wiley later shifted its focus to scientific, technical, and engineering subject areas, abandoning its literary interests. Wiley's son John (born in Flatbush, New York, October 4, 1808; died in East ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carborane Acid
Carborane acids (X, Y, Z = H, Alk, F, Cl, Br, CF3) are a class of superacids, some of which are estimated to be at least one million times stronger than 100% pure sulfuric acid in terms of their Hammett acidity function values (''H''0 ≤ −18) and possess computed p''K''a values well below −20, establishing them as some of the strongest known Brønsted acids. The best-studied example is the highly chlorinated derivative . The acidity of was found to vastly exceed that of triflic acid, , and bistriflimide, , compounds previously regarded as the strongest isolable acids. Their high acidities stem from the extensive delocalization of their conjugate bases, carboranate anions (CXB11Y5Z6−), which are usually further stabilized by electronegative groups like Cl, F, and CF3. Due to the lack of oxidizing properties and the exceptionally low nucleophilicity and high stability of their conjugate bases, they are the only superacids known to protonate C60 fullerene without decompo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perchloric Acid
Perchloric acid is a mineral acid with the formula H Cl O4. It is an oxoacid of chlorine. Usually found as an aqueous solution, this colorless compound is a stronger acid than sulfuric acid, nitric acid and hydrochloric acid. It is a powerful oxidizer when hot, but aqueous solutions up to approximately 70% by weight at room temperature are generally safe, only showing strong acid features and no oxidizing properties. Perchloric acid is useful for preparing perchlorate salts, especially ammonium perchlorate, an important rocket fuel component. Perchloric acid is dangerously corrosive and readily forms potentially explosive mixtures. History Perchloric acid was first synthesized (together with potassium perchlorate) by Austrian chemist and called "oxygenated chloric acid" in mid-1810s. French pharmacist Georges-Simon Serullas introduced the modern designation along with discovering its solid monohydrate, which he mistook for an anhydride. Berzelius produced dilute perchloric acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triflic Acid
Triflic acid, the short name for trifluoromethanesulfonic acid, TFMS, TFSA, HOTf or TfOH, is a sulfonic acid with the chemical formula CF3SO3H. It is one of the strongest known acids. Triflic acid is mainly used in research as a catalyst for esterification. It is a hygroscopic, colorless, slightly viscous liquid and is soluble in polar solvents. Synthesis Trifluoromethanesulfonic acid is produced industrially by electrochemical fluorination (ECF) of methanesulfonic acid CH3SO3H + 4 HF ->CF3SO2F + H2O + 3 H2 The resulting CF3SO2F is hydrolyzed, and the resulting triflate salt is reprotonated. Alternatively, trifluoromethanesulfonic acid arises by oxidation of trifluoromethylsulfenyl chloride: CF3SCl + 2 Cl2 + 3 H2O -> CF3SO3H + 5 HCl Triflic acid is purified by distillation from triflic anhydride. Historical Trifluoromethanesulfonic acid was first synthesized in 1954 by Robert Haszeldine and Kidd by the following reaction: : Reactions As an acid In the laboratory, trif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carborane Acid
Carborane acids (X, Y, Z = H, Alk, F, Cl, Br, CF3) are a class of superacids, some of which are estimated to be at least one million times stronger than 100% pure sulfuric acid in terms of their Hammett acidity function values (''H''0 ≤ −18) and possess computed p''K''a values well below −20, establishing them as some of the strongest known Brønsted acids. The best-studied example is the highly chlorinated derivative . The acidity of was found to vastly exceed that of triflic acid, , and bistriflimide, , compounds previously regarded as the strongest isolable acids. Their high acidities stem from the extensive delocalization of their conjugate bases, carboranate anions (CXB11Y5Z6−), which are usually further stabilized by electronegative groups like Cl, F, and CF3. Due to the lack of oxidizing properties and the exceptionally low nucleophilicity and high stability of their conjugate bases, they are the only superacids known to protonate C60 fullerene without decompo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Organic Chemistry
''The Journal of Organic Chemistry'', colloquially known as ''JOC'', is a peer-reviewed scientific journal for original contributions of fundamental research in all branches of theory and practice in organic and bioorganic chemistry. It is published by the publishing arm of the American Chemical Society, with 24 issues per year. According to the ''Journal Citation Reports'', the journal had a 2023 impact factor of 3.3 and it is the journal that received the most cites (100,091 in 2017) in the field of organic chemistry. According to Web of Knowledge (and as December 2012), eleven papers from the journal have received more than 1,000 citations, with the most cited paper having received 7,967 citations. The current editor-in-chief is Scott J. Miller from Yale University. Indexing ''J. Org. Chem.'' is currently indexed in: See also * Organic Letters *Organometallics ''Organometallics'' is a biweekly journal published by the American Chemical Society. Its area of focus is o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorosulfuric Acid
Fluorosulfuric acid (IUPAC name: sulfurofluoridic acid) is the inorganic compound with the chemical formula . It is one of the strongest acids commercially available. It is a tetrahedral molecule and is closely related to sulfuric acid, , substituting a fluorine atom for one of the hydroxyl groups. It is a colourless liquid, although commercial samples are often yellow.Erhardt Tabel, Eberhard Zirngiebl, Joachim Maas "Fluorosulfuric Acid" in "Ullmann's Encyclopedia of Industrial Chemistry" 2005, Wiley-VCH, Weinheim. Properties Fluorosulfuric acid is a free-flowing colorless liquid. It is soluble in polar organic solvents (e.g. nitrobenzene, acetic acid, and ethyl acetate), but poorly soluble in nonpolar solvents such as alkanes. is one of the strongest known simple Brønsted acids. It has an ''H''0 value of −15.1 compared to −12 for sulfuric acid. The combination of and the Lewis acid antimony pentafluoride produces "Magic acid", which is a far stronger protonating ag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angewandte Chemie International Edition
''Angewandte Chemie'' (, meaning "Applied Chemistry") is a weekly peer-reviewed scientific journal that is published by Wiley-VCH on behalf of the German Chemical Society (Gesellschaft Deutscher Chemiker). Publishing formats include feature-length reviews, short highlights, research communications, minireviews, essays, book reviews, meeting reviews, correspondences, corrections, and obituaries. This journal contains review articles covering all aspects of chemistry. According to the ''Journal Citation Reports'', the journal had a 2023 impact factor of 16.1. Editions The journal appears in two editions with separate volume and page numbering: a German edition, ''Angewandte Chemie'', and a fully English-language edition, ''Angewandte Chemie International Edition''. The editions are identical in content with the exception of occasional reviews of German-language books or German translations of IUPAC recommendations. Publication history In 1887, Ferdinand Fischer established the '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Crystallography
X-ray crystallography is the experimental science of determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to Diffraction, diffract in specific directions. By measuring the angles and intensities of the X-ray diffraction, a crystallography, crystallographer can produce a three-dimensional picture of the density of electrons within the crystal and the positions of the atoms, as well as their chemical bonds, crystallographic disorder, and other information. X-ray crystallography has been fundamental in the development of many scientific fields. In its first decades of use, this method determined the size of atoms, the lengths and types of chemical bonds, and the atomic-scale differences between various materials, especially minerals and alloys. The method has also revealed the structure and function of many biological molecules, including vitamins, drugs, proteins and nucleic acids such as DNA. X-ray crystall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grotthuss Mechanism
The Grotthuss mechanism (also known as proton jumping) is a model for the process by which an 'excess' proton diffuses through the hydrogen bond network of water molecules or other hydrogen-bonded liquids through the formation and concomitant cleavage of covalent bonds involving neighboring molecules. In his 1806 publication “Theory of decomposition of liquids by electrical currents”, Theodor Grotthuss proposed a theory of water conductivity. Grotthuss envisioned the electrolytic reaction as a sort of ‘bucket line’ where each oxygen atom simultaneously passes and receives a single hydrogen ion. It was an astonishing theory to propose at the time, since the water molecule was thought to be OH, not H2O, and the existence of ions was not fully understood. On its 200th anniversary, his article was reviewed by Cukierman. Although Grotthuss was using an incorrect empirical formula of water, his description of the passing of protons through the cooperation of neighboring water m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
