With Inorganic Fluorides

4-Oxo-4/7-l-benzotellurines reacted with boron trifluoride, phosphorus pentafluoride, and ethyl fluorosulfate to give 1-benzotellurinium salts. 

4-Ethoxy-7-methoxy-2-phenyl-l-benzotelluriniuni Fluorosulfate 5.0 g (14 mmol) of 2-phenyl-7-methoxy-4-0X0-477-1-benzotellurin are added to 20 m/] of freshly distilled ethyl fluorosulfate, the mixture is stirred under nitrogen at 60° for 10 min, cooled to 20°, and 200 ml] of diethyl ether are added. The red solid is filtered off and recrystallized from acetonitrile yield 6.0 g (87%) m.p. 216°. 

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Interaction of Organic Halides or Polyhalides with Inorganic Fluorides... 

O Hagan and coworkers recently found that fluorodesulfuration is not only a versatile tool for the synthetic organic chemist but also - in a non-oxidative variant - so far the only known pathway in nature for enzymatic incorporation of inorganic fluoride ions into secondary metabolites [166] (Scheme 2.75). As the key step of this enzymatic reaction sequence a trialkylsulfonium ion (SAM) reacts with inorganic fluoride in a nucleophilic replacement with methionine as the leaving group. 

On the other hand, hexafluoropropylene oxide is stable up to 150°C. The polymerization is carried out with inorganic fluoride ions in solvents such as a-methyl-co-methoxy-tetra(oxyethylene) (tetraglyme) ... 

Adoption of a sol-gel method to optical fluoride materials started with inorganic fluoride glasses. At first, the sol-gel processing appeared rather challenging because fluoride gels were not known and little was known about the chemical reaction between fluorinating... 

Alkyl fluorides may be prepared in moderate yield by interaction of an alkyl bromide with anhydrous potassium fluoride in the presence of dry ethylene glycol as a solvent for the inorganic fluoride, for example ... 

The balance of hydrogen fluoride is used ia appHcations such as stainless steel pickling inorganic fluoride production, alkylation (qv), uranium enrichment, and fluorine production. Hydrogen fluoride is used to convert uranium oxide to UF which then reacts with elemental fluorine to produce volatile UF. ... 

Catalysis. Catalytic properties of the activated carbon surface are useful in both inorganic and organic synthesis. For example, the fumigant sulfuryl fluoride is made by reaction of sulfur dioxide with hydrogen fluoride and fluorine over activated carbon (114). Activated carbon also catalyzes the addition of halogens across a carbon—carbon double bond in the production of a variety of organic haUdes (85) and is used in the production of phosgene... 

Alkyl fluorides have been prepared by reaction between elementary fluorine and the paraffins, by the addition of hydrogen fluoride to olefins, by the reaction of alkyl halides with mercurous fluoride, with mercuric fluoride, with silver fluoride, or with potassium fluoride under pressure. The procedure used is based on that of Hoffmann involving interaction at atmospheric pressure of anhydrous potassium fluoride with an alkyl halide in the presence of ethylene glycol as a solvent for the inorganic fluoride a small amount of olefin accompanies the alkyl fluoride produced and is readily removed by treatment with bromine-potassium bromide solution. Methods for the preparation of alkyl monofluorides have been reviewed. ... 

These reactions are most important for the preparation of acyl fluorides. " Acyl chlorides and anhydrides can be converted to acyl fluorides by treatment with polyhydrogen fluoride-pyridine solution" or with liquid HF at — 10°C. Formyl fluoride, which is a stable compound, was prepared by the latter procedure from the mixed anhydride of formic and acetic acids. Acyl fluorides can also be obtained by reaction of acyl chlorides with KF in acetic acid or with DAST. Carboxylic esters and anhydrides can be converted to acyl halides other than fluorides by the inorganic acid halides mentioned in 10-77, as well as with PhsPXa (X = Cl or but this is seldom done. Halide exchange can be carried out in a... 

Stability Unstable at >110°C and decomposes at >200°C. Hydrogen fluoride (20% by weight) is a decomposition product which readily reacts with metals or metal compounds to form stable inorganic fluoride compounds... 

Halex [Halogen exchange] A process for making fluoro-aromatic compounds by reacting the corresponding chloro- or bromo-aromatic comounds with an inorganic fluoride, usually potassium fluoride. Widely used for the manufacture of fluoro-intermediates. 

After a large number of experiments, we found that the preparation could be run virtually as a one-stage process. The whole process consists simply in adding phosphorus trichloride to isopropyl alcohol, dissolved in a solvent such as carbon tetrachloride, without external cooling. The crude product (still in the solvent) is chlorinated and then heated with an inorganic fluoride, e.g. sodium fluoride. After filtration, the solvent is distilled off and the pure di-isopropyl phosphorofluoridate distilled. ... 

The interaction of alkali salts with inorganic and organic acids has been extensively studied by the same group. In the case of alkali fluorides it was shown that milling leads to proton transfer and to formation of KHF2, while the reactivity of fluorides follows the order KF>NH4F>NaF>LiF, Cap2 [71b,c]. 

Elemental fluorine, which is a member of the halogen family, is a pale yellow-green, irritating gas with a sharp odour and atomic mass of 18.998. Fluorine is chemically most reactive of all the elements and does not therefore occur naturally in the free state. In combination it comprises 0.065% of the earth s crust, being the 13th element in abundance [1], and is an inevitable part of the biosphere and human life. The term fluorine is, in this report, used to denote the element in any of its forms and fluoride to denote free inorganic fluoride to which a fluoride ion-selective electrode (ISE) responds. 

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