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Hexafluoroacetone Hydrate
Hexafluoroacetone (HFA) is a chemical compound with the formula (CF3)2CO. It is structurally similar to acetone; however, its reactivity is markedly different. It is a colourless, hygroscopic, nonflammable, highly reactive gas characterized by a musty odour. According to electron diffraction, HFA and acetone adopt very similar structures, the C-O distance being only longer in the fluorinated compound (124.6 vs 121.0 pm), possibly due to steric effects. The term "hexafluoroacetone" can refer to the sesquihydrate (1.5 H2O), which is a hemihydrate of hexafluoropropane-2,2-diol , a geminal diol. Hydrated HFA behaves differently from the anhydrous material. Synthesis The industrial route to HFA involves treatment of hexachloroacetone with HF (a Finkelstein reaction): :(CCl3)2CO + 6 HF → (CF3)2CO + 6 HCl Laboratory methods Hydrated HFA can be converted to HFA by treatment with hot sulfuric acid. It has also be prepared from hexafluoropropylene oxide, which will rearrange to g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ketone
In organic chemistry, a ketone is an organic compound with the structure , where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group (a carbon-oxygen double bond C=O). The simplest ketone is acetone (where R and R' are methyl), with the formula . Many ketones are of great importance in biology and 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 retained IUPAC names, although some introdu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexafluoropropylene Oxide
Hexafluoropropylene oxide (HFPO) is an intermediate used in industrial organofluorine chemistry; specifically it is a monomer for fluoropolymers. This colourless gas is the epoxide of hexafluoropropylene, which is a fluorinated analog of propylene oxide, HFPO is produced by Chemours and 3M and as a precursor to the lubricant Krytox and related materials. It is generated by oxidation of perfluoropropylene, e.g. with oxygen as well as other oxidants. Reactivity Fluoride catalyzes the formation of perfluorinated polyethers such as Krytox. The initial step entails nucleophilic attack at the middle carbon to give the perfluoropropoxide anion, which in turn attacks another monomer. This process generates a polymer terminated by an acyl fluoride, which is hydrolyzed to the carboxylic acid which is decarboxylated with fluorine. The net polymerization reaction can be represented as: : Upon heating above 150 °C, HFPO decomposes to trifluoroacetyl fluoride and difluorocarbene: : The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bisphenol AF
Bisphenol AF (BPAF) is a fluorinated organic compound that is an analogue of bisphenol A in which the two methyl groups are replaced with trifluoromethyl groups. It exists as a white to light-gray powder. Biological and Chemical Action Bisphenol AF is an endocrine disrupting chemical. Whereas BPA binds with human estrogen-related receptor gamma (ERR-γ), BPAF all but ignores ERR-γ. Instead, BPAF activates ERR-α and binds to and disables ERR-β. The chemical shifts in 1H, 13C and 19F NMR spectroscopy are given in the literature. Applications Bisphenol AF is used as a crosslinking agent for certain fluoroelastomers and as a monomer for polyimides, polyamides, polyesters, polycarbonate copolymers and other specialty polymers. Polymers containing Bisphenol AF are useful in specialties such as high-temperature composites and electronic materials. Industries include cosmetics, chemical manufacturing, production of metals and rubber. It can also be a plastic additive. See als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Midaflur
Midaflur (INN; EXP 338) is an extremely stable 3-imidazoline derivative with central skeletal muscle relaxant and sedative properties in humans and other species of mammals, exhibiting consistently high oral bioavailability and a long duration of action. While its pharmacodynamics remain poorly understood, midaflur resembles meprobamate and pentobarbital in terms of observed effects while being considerably more potent. See also * Propofol * Pentobarbital Pentobarbital (US) or pentobarbitone (British and Australian) is a short-acting barbiturate typically used as a sedative, a preanesthetic, and to control convulsions in emergencies. It can also be used for short-term treatment of insomnia but ... References {{Hypnotics General anesthetics Hypnotics Sedatives Trifluoromethyl compounds Imidazolines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Building Block (chemistry)
Building block is a term in chemistry which is used to describe a virtual molecular fragment or a real chemical compound the molecules of which possess reactive functional groups. Building blocks are used for bottom-up modular assembly of molecular architectures: Nanoparticle, nano-particles, metal-organic frameworks, organic molecular constructs, Supramolecular chemistry, supra-molecular complexes. Using building blocks ensures strict control of what a final compound or a (supra)molecular construct will be. Building blocks for medicinal chemistry In medicinal chemistry, the term defines either imaginable, virtual molecular fragments or chemical reagents from which drugs or drug candidates might be constructed or synthetically prepared. Virtual building blocks Virtual building blocks are used in drug discovery for drug design and virtual screening, addressing the desire to have controllable molecular morphologies that interact with biological targets. Of special interest for t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexafluoroisobutylene
Hexafluoroisobutylene is an organofluorine compound with the formula (CF3)2C=CH2. This colorless gas is structurally similar to isobutylene. It is used as a comonomer in the production of modified poly vinylidene fluoride. It is produced in a multistep process starting with the reaction of acetic anhydride with hexafluoroacetone. It is oxidized by sodium hypochlorite to hexafluoroisobutylene oxide. As expected, it is a potent dienophile.{{cite journal, title=The chemistry and utility of hexafluoroisobutylene (HFIB) and hexafluoroisobutylene oxide (HFIBO), author= Murphy, Peter M., journal=Journal of Fluorine Chemistry, year=2013, volume=156, pages=345–362, doi=10.1016/j.jfluchem.2013.07.015, bibcode= 2013JFluC.156..345M See also *Perfluoroisobutene Perfluoroisobutene (PFIB) is the perfluorocarbon with the formula . Classified as a perfluoroalkene, it is the fluorinated counterpart of the hydrocarbon isobutene. This colorless gas is notable for its high toxicity. Productio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexafluoro-2-propanol
Hexafluoroisopropanol, commonly abbreviated HFIP, is the organic compound with the formula (CF3)2CHOH. This fluoroalcohol finds use as solvent in organic chemistry. Hexafluoro-2-propanol is transparent to UV light with high density, low viscosity and low refractive index. It is a colorless, volatile liquid with a pungent odor. Production Hexafluoro-propan-2-ol is prepared from hexafluoropropylene through hexafluoroacetone, which is then hydrogenated.Günter Siegemund, Werner Schwertfeger, Andrew Feiring, Bruce Smart, Fred Behr, Herward Vogel, Blaine McKusick “Fluorine Compounds, Organic” in ''Ullmann's Encyclopedia of Industrial Chemistry'', John Wiley & Sons, 2007. :(CF3)2CO + H2 → (CF3)2CHOH Solvent properties As a solvent, hexafluoro-2-propanol is polar and exhibits strong hydrogen bonding properties. Testament to the strength of its hydrogen-bonding tendency is the fact that its 1:1 complex with THF distills near 100 °C. It has a relatively high dielectric co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Iodate
Potassium iodate ( K I O3) is an ionic inorganic compound with the formula . It is a white salt that is soluble in water. Preparation and properties It can be prepared by reacting a potassium-containing base such as potassium hydroxide with iodic acid, for example: : HIO3 + KOH → KIO3 + H2O It can also be prepared by adding iodine to a hot, concentrated solution of potassium hydroxide: :3 I2 + 6 KOH → KIO3 + 5 KI + 3 H2O Or by fusing potassium iodide with potassium chlorate, bromate or perchlorate, the melt is extracted with water and potassium iodate is isolated from the solution by crystallization: :KI + KClO3 → KIO3 + KCl The analogous reaction with potassium hypochlorite is also possible:KI + 3KOCl → 3KCl + KIO3Conditions/substances to avoid include: heat, shock, friction, combustible materials, reducing materials, aluminium, organic compounds, carbon, hydrogen peroxide and sulfides. Applications Potassium iodate is sometimes used for iodination of tabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexafluorothioacetone
Hexafluorothioacetone is an organic perfluoro thione compound with formula CF3CSCF3. At standard conditions it is a blue gas. Production Hexafluorothioacetone was first produced by Middleton in 1961 by boiling ''bis''-(perfluoroisopropyl)mercury with sulfur. Properties Hexafluorothioacetone boils at 8 °C. Below this it is a blue liquid. Colour The blue colour is due to absorption in the visible light range with bands at 800–675 nm and 725–400 nm. These bands are due to T1–S0 and S1–S0 transitions. There is also a strong absorption in ultraviolet around 230-190 nm. Reactions Hexafluorothioacetone acts more like a true thiocarbonyl (C=S) than many other thiocarbonyl compounds, because it is not able to form thioenol compounds (=C-S-H), and the sulfur is not in a negative ionized state (C-S−). Hexafluorothioacetone is not attacked by water or oxygen at standard conditions as are many other thiocarbonyls. Bases trigger the formation of a dimer 2,2,4 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dithietane
A dithietane is a saturated heterocyclic compound that contain two Valence (chemistry), divalent sulfur atoms and two Orbital hybridisation, sp3-hybridized carbon atoms. Two isomers are possible for this class of organosulfur compounds: 1,2-Dithietanes 1,2-dithietanes, 4-membered rings where the two sulfur atoms are adjacent, are very rare. The first stable 1,2-dithietane to be reported was the dithiatopazine, formed by intramolecular photodimerization of a dithiocarbonyl compound. 1,2-Dithietanes are to be distinguished from 1,2-dithietes, containing two adjacent sulfur atoms and two Orbital hybridisation, sp2-hybridized carbon centers. A stable 1,2-dithietane ''derivative'' is ''trans''-3,4-diethyl-1,2-dithietane 1,1-dioxide, formed by the spontaneous Dimer (chemistry), dimerization of the lachrymatory agent syn-propanethial-S-oxide, found in onion. 1,3-Dithietanes In 1,3-dithietanes, the sulfur atoms are non-adjacent. 1,3-Dithietane itself, a colorless, easily sublimed, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Fluoride
Potassium fluoride is the chemical compound with the formula KF. After hydrogen fluoride, KF is the primary source of the fluoride ion for applications in manufacturing and in chemistry. It is an alkali halide salt and occurs naturally as the rare mineral carobbiite. Solutions of KF will etch glass due to the formation of soluble fluorosilicates, although HF is more effective. Preparation Potassium fluoride is prepared by reacting potassium carbonate with hydrofluoric acid. Evaporation of the solution forms crystals of potassium bifluoride. The bifluoride on heating yields potassium fluoride: : : Platinum or heat resistant plastic containers are often used for these operations. Potassium chloride converts to KF upon treatment with hydrogen fluoride. In this way, potassium fluoride is recyclable. Crystalline properties KF crystallizes in the cubic NaCl crystal structure. The lattice parameter at room temperature is 0.266 nm. Applications in organic chemistry In organic c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
