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Perfluoroalcohol
Fluoroalcohols are organofluorine compounds consisting of an alcohol functional group with at least one C-F bond. These compounds often have distinctive solvent properties. Perfluoroalcohols Most primary and secondary perfluoroalcohols are unstable, for example trifluoromethanol eliminates hydrogen fluoride, forming carbonyl fluoride. This reaction is reversible. : ⇌ + {{chem, H, F (I) Stable perfluorinated alcohols include nonafluoro-tert-butyl alcohol ((CF3)3COH) and pentafluorophenol (C6F5OH). Partially fluorinated alcohols Numerous partially fluorinated alcohols are known. Trifluoroethanol is a popular solvent. Fluorotelomer alcohols are precursors to perfluorocarboxylic acids. Pirkle's alcohol is used a chiral shift reagent in nuclear magnetic resonance spectroscopy Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy or magnetic resonance spectroscopy (MRS), is a spectroscopic technique to observe local magnetic fields around atomic nuc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organofluorine Compound
Organofluorine chemistry describes the chemistry of the organofluorines, organic compounds that contain the carbon–fluorine bond. Organofluorine compounds find diverse applications ranging from oil and water repellents to pharmaceuticals, refrigerants, and reagents in catalysis. In addition to these applications, some organofluorine compounds are pollutants because of their contributions to ozone depletion, global warming, bioaccumulation, and toxicity. The area of organofluorine chemistry often requires special techniques associated with the handling of fluorinating agents. The carbon–fluorine bond Fluorine has several distinctive differences from all other substituents encountered in organic molecules. As a result, the physical and chemical properties of organofluorines can be distinctive in comparison to other organohalogens. # The carbon–fluorine bond is one of the strongest in organic chemistry (an average bond energy around 480 kJ/molKirsch, Peer ''Modern fluoroorga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alcohol (chemistry)
In chemistry, an alcohol is a type of organic compound that carries at least one hydroxyl () functional group bound to a saturated carbon atom. The term ''alcohol'' originally referred to the primary alcohol ethanol (ethyl alcohol), which is used as a drug and is the main alcohol present in alcoholic drinks. An important class of alcohols, of which methanol and ethanol are the simplest examples, includes all compounds which conform to the general formula . Simple monoalcohols that are the subject of this article include primary (), secondary () and tertiary () alcohols. The suffix ''-ol'' appears in the IUPAC chemical name of all substances where the hydroxyl group is the functional group with the highest priority. When a higher priority group is present in the compound, the prefix ''hydroxy-'' is used in its IUPAC name. The suffix ''-ol'' in non-IUPAC names (such as paracetamol or cholesterol) also typically indicates that the substance is an alcohol. However, some compou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Functional Group
In organic chemistry, a functional group is a substituent or moiety in a molecule that causes the molecule's characteristic chemical reactions. The same functional group will undergo the same or similar chemical reactions regardless of the rest of the molecule's composition. This enables systematic prediction of chemical reactions and behavior of chemical compounds and the design of chemical synthesis. The reactivity of a functional group can be modified by other functional groups nearby. Functional group interconversion can be used in retrosynthetic analysis to plan organic synthesis. A functional group is a group of atoms in a molecule with distinctive chemical properties, regardless of the other atoms in the molecule. The atoms in a functional group are linked to each other and to the rest of the molecule by covalent bonds. For repeating units of polymers, functional groups attach to their nonpolar core of carbon atoms and thus add chemical character to carbon chains. Fun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trifluoromethanol
Trifluoromethanol is the organic compound with the formula . It is also referred to as perfluoromethanol or trifluoromethyl alcohol. The compound is the simplest perfluoroalcohol. The substance is a colorless gas, which is unstable at room temperature. Synthesis Like all primary and secondary perfluoroalcohols, trifluoromethanol eliminates hydrogen fluoride in an endothermic reaction and forms carbonyl fluoride. : ⇌ + (I) At temperatures in the range of -120 °C, trifluoromethanol can be prepared from trifluoromethoxy chloride and hydrogen chloride: : + → + (II) In this reaction, the recombination of a partially positively charged chlorine atom (in trifluoromethoxy chloride) with a partially negatively charged chlorine atom (in hydrogen chloride) is used as elemental chlorine. The undesired products, by-products chlorine, hydrogen chloride, and chlorotrifluoromethane, can be removed by evaporation at -110 °C. Trifluoromethanol has a melting point of -82&n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Fluoride
Hydrogen fluoride (fluorane) is an inorganic compound with the chemical formula . This colorless gas or liquid is the principal industrial source of fluorine, often as an aqueous solution called hydrofluoric acid. It is an important feedstock in the preparation of many important compounds including pharmaceuticals and polymers, e.g. polytetrafluoroethylene (PTFE). HF is widely used in the petrochemical industry as a component of superacids. Hydrogen fluoride boils at near room temperature, much higher than other hydrogen halides. Hydrogen fluoride is an extremely dangerous gas, forming corrosive and penetrating hydrofluoric acid upon contact with moisture. The gas can also cause blindness by rapid destruction of the corneas. History In 1771 Carl Wilhelm Scheele prepared the aqueous solution, hydrofluoric acid in large quantities, although hydrofluoric acid had been known in the glass industry before then. French chemist Edmond Frémy (1814–1894) is credited with discoveri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonyl Fluoride
Carbonyl fluoride is a chemical compound with the formula COF2. It is a carbon oxohalide. This gas, like its analog phosgene, is colourless and highly toxic. The molecule is planar with ''C''2v symmetry, bond lengths of 1.174 Å (C=O) and 1.312 Å (C–F), and an F–C–F bond angle of 108.0°. Preparation and properties Carbonyl fluoride is usually produced as a decomposition product of fluorinated hydrocarbons in the thermal decomposition thereof, for example from trifluoromethanol or tetrafluoromethane in the presence of water: : + → + 2 Carbonyl fluoride can also be prepared by reaction of phosgene with hydrogen fluoride and the oxidation of carbon monoxide, although the latter tends to result in over-oxidation to carbon tetrafluoride. The oxidation of carbon monoxide with silver difluoride is convenient: : + 2 → + 2 Carbonyl fluoride is unstable in the presence of water, hydrolyzing to carbon dioxide and hydrogen fluoride: : + → + 2 Safety Carbonyl fluor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nonafluoro-tert-butyl Alcohol
Nonafluoro-''tert''-butyl alcohol (''IUPAC name'': 1,1,1,3,3,3-hexafluoro-2-(trifluoromethyl)propan-2-ol) is a fluoroalcohol. It is the perfluorinated analog of ''tert''-butyl alcohol. Notably, as a consequence of its electron withdrawing fluorine substituents, it is very acidic for an alcohol, with a p''K''a value of 5.4, similar to that of a carboxylic acid. As another consequence of being a perfluorinated compound, it is also one of the lowest boiling alcohols, with a boiling point lower than that of methanol. Synthesis It is prepared by addition of trichloromethyllithium to hexafluoroacetone, followed by halogen exchange with antimony pentafluoride. The aluminate derived from its alkoxide anion, tetrakis ,1,1,3,3,3-hexafluoro-2-(trifluoromethyl)propan-2-oxyluminate(1–), – is used as a weakly coordinating anion. See also * 2,2,2-Trifluoroethanol * 1,1,1,3,3,3-Hexafluoro-2-propanol * Hexafluoroacetone Hexafluoroacetone (HFA) is a chemical compound with the form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentafluorophenol
Pentafluorophenol is the organofluorine compound (specifically a fluoroalcohol) with the formula C6F5OH. This is the perfluorinated analogue of phenol. It is a white odorless solid that melts just above room temperature. With a pKa of 5.5, it is one of the most acidic phenols. Uses Pentafluorophenol is used to prepare pentafluorophenyl esters, which are active esters useful in peptide synthesis In organic chemistry, peptide synthesis is the production of peptides, compounds where multiple amino acids are linked via amide bonds, also known as peptide bonds. Peptides are chemically synthesized by the condensation reaction of the carboxyl .... Environmental hazards Pentafluorophenol is considered hazardous because of oral, dermal and inhalation toxicity and because it causes "severe skin burns and eye damage." References {{Reflist Fluoroarenes Perfluorinated compounds Phenols ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trifluoroethanol
2,2,2-Trifluoroethanol is the organic compound with the formula CF3CH2OH. Also known as TFE or trifluoroethyl alcohol, this colourless, water-miscible liquid has a smell reminiscent of ethanol. Due to the electronegativity of the trifluoromethyl group, this alcohol exhibits a stronger acidic character compared to ethanol. Synthesis Trifluoroethanol is produced industrially by hydrogenation or the hydride reduction of derivatives of trifluoroacetic acid, such as the esters or acyl chloride. TFE can also be prepared by hydrogenolysis of compounds of generic formula CF3−CHOH−OR (where R is hydrogen or an alkyl group containing from one to eight carbon atoms), in the presence of a palladium containing catalyst deposited on activated charcoal. As a co-catalyst for this conversion tertiary aliphatic amines like triethylamine are commonly employed. Uses Trifluoroethanol is used as a solvent in organic chemistry. Oxidations of sulfur compounds using hydrogen peroxide are effectivel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorotelomer Alcohol
Fluorotelomer alcohols, or FTOHs, are fluorotelomers with an alcohol functional group. They are volatile precursors to perfluorinated carboxylic acids, such as PFOA and PFNA, and other compounds. Naming Commonly, an individual fluorotelomer alcohol molecule is named by the number of carbons that are fluorinated versus the number that are hydrocarbon-based. For example, 8:2 fluorotelomer alcohol would represent a molecule with 8 fluorinated carbons and a 2 carbon ethyl alcohol group. The structure of a fluorotelomer alcohol is most commonly F(CF2)nCH2CH2OH, where ''n'' is an even number. Chemistry The synthesis of fluorotelomer alcohols requires a varying number of tetrafluoroethylene monomers that form an oligomer with a pentafluoroethyl iodide telogen. The fluorinated iodide then undergoes an addition with ethylene to form an organoiodine compound with increased synthesis possibilities. The terminal iodine is replaced by a hydroxyl group to yield the fluorotelomer alcohol. The f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perfluorocarboxylic Acid
Perfluoroalkyl carboxylic acids (PFCAs), or perfluorocarboxylic acids are compounds of the formula CnF(2n+1)CO2H that belong to the class of per- and polyfluoroalkyl substances. The simplest example is trifluoroacetic acid. These compounds are organofluorine analogues of ordinary carboxylic acids, but they are stronger by several pKa units and they exhibit great hydrophobic character. Perfluoroalkyl dicarboxylic acids (PFdiCAs) are also known, e.g. C2F4(CO2H)2.Günter Siegemund, Werner Schwertfeger, Andrew Feiring, Bruce Smart, Fred Behr, Herward Vogel, Blaine McKusick "Fluorine Compounds, Organic" Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2002. Applications Trifluoroacetic acid is a widely employed acid, used for example in the synthesis of peptides. Its esters are useful in analytical chemistry. Longer-chain perfluoroalkyl carboxylic acids, e.g. with five to nine carbons, are useful fluorosurfactants and emulsifiers used in the production of poly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
