Fluorination of organics

The tetrafluorides of the elements can be prepared. They are all less stable than the corresponding hexafluorides and are hydrolysed readily by water. They can all be used as fluorinating agents and sulphur tetrafluoride is extensively used for this purpose, for example the fluorination of organic carbonyl groups ... 

Mercury(II) fluoride has been used in the process for manufacture of fluoride glass (qv) for fiber optics (qv) appHcations (11) and in photochemical selective fluorination of organic substrates (12). It is available from Advance Research Chemicals, Aldrich Chemicals, Johnson/Matthey, Aesar, Cerac, Strem, and PCR in the United States. The 1993 annual consumption was less than 50 kg the price was 800—1000/kg. 

Fluorination of organic compounds using high valency metallic fluorides (14) may be represented as follows ... 

Table 1. Direct Fluorination of Organic Compounds Using Batch Reaction Techniques...

The Exhaustive Fluorination of Organic Compounds by High Valency Metal Fluorides, M. Stacey and J. C. Tatlow, Adv. Fluorine Chem., 1 (1960) 166-198. 

Dining the fluorination of organic materials by passing hydrogen fluoride into a vigorously stirred suspension of the oxide (to form transiently mercury difluoride, a powerful fluorinator), it is essential to use adequate and effective cooling below 0°C to prevent loss of control of the reaction system. 

The violent nature ofreactions between fluorine and hydrocarbon compounds has already been noted here, and the direct fluorination of organic polymers is not a exception it is so exothermic that if the reaction is not controlled, it generally leads to fragmentation and charring of the substrate. Moderation of the reaction rate can be effected by ... 

Anodic nucleophilic functionalization of an a-carbon turned out to be particularly efficient for the fluorination of organic sulfides. The introduction of one or two fluorine atoms at the a-carbon was reported in several papers for sulfides bearing EWGs = CN, COMe, COPh, CF3, COzEt, CONEt2, PO(OEt)2) (Scheme 18) [75-78], Two systems are mainly used as the supporting electrolyte and fluorine source at a time namely, EtsN-SHF and Etr NF. 

Antimony pentafluoride is used as a fluorinating agent for fluorination of organic compounds. 

S. Rozen, Elemental fluorine as a legitimate reagent for selective fluorination of organic compounds, Acc. Chem. Res. 21 (1988) 307-312. 

G.S. Lai, Site-selective fluorination of organic compounds using 1-alkyl-4-fluoro-1, 4-diazabicyclo[2.2.2]octane salts (selectfluor reagents), J. Org. Chem. 58 (1993) 2791-2796. 

Meinert and others [85] have stated that their concept for the electrochemical fluorination of organic compounds is based on the assumption that the first step is the anodic oxidation of the organic molecule. The electrochemical process is promoted by weakening of the C-H bonds due to hydrogen-fluorine bridges. After anodic withdrawal, the C-F bond is formed by insertion of a fluoride ion, present in the Helmholtz-double-layer at the electrode surface. 

Hydrocarbons inflame spontaneously in F2, giving fluorocarbons and HF. Controlled fluorination of organic compounds is possible by electrolyzing them in liquid HF (bp 20 °C) at a nickel anode, at voltages just below that needed to evolve F2 ... 

The anodic partial fluorination of organic compounds occurs in weak Lewis base solvents (AN, CH2CI2, DME) containing fluoride ions (QH Ia QH + e f H+ Q - F or QH -e-H+ > Q+ — - Q - F. This occurs because F in aprotic solvents is ex... 

C1F 54.46 - 155.6/- 100.1 + + + + also usable for synthesis of hypofluorites and oxidative S- or Se-fluorinations of organic sulfur and selenium compounds, frequently in situ preparation of the agent from A -chloro-substituted amides and HF, HF-containing systems or AgF 4, 7... 

Direct fluorination of organic compounds using fluorine is an important methodology when considering safety, environmental and recycling problems. Fluorine can be fed into the reactor from a cylinder for the direct fluorination procedure, but this method has economic and safety disadvantages. Electrochemical generation of fluorine has recently been adopted for fluorination even in the laboratory. It can be operated easily and safely, because operational difficulties have been improved. 

Trifluoroacetyl hypofluorite is the main product in the low-temperature fluorination of sodium trifluoroacetate in suspension in an inert solvent, and can be further transformed to pentafluoro-(fluoroxy)ethane.2 In some cases, the reaction mixture of up to four reactive products [fluoroxy, bis(fluoroxy) and acyl hypofluorites], formed in reactions with various acid salts, c.g. 5, has been directly used for the fluorination of organic molecules.1 " 5... 

Table 3. Fluorination of Organic Molecules with 1-Fluoropyridinium Triflates...

Table 6. Fluorination of Organic Compounds with 1-Fluoropyridinium Pyridine Heptafluorodiborate (NFPy, 33) in Acetonitrile69...

Mercury(II) fluoride is a white, fluffy powder, extremely sensitive to moisture. In the presence of water, a dihydrate salt forms. If the salt is to be used for the fluorination of organic compounds, it must be kept rigorously dry.55 Earlier work is described in Houben-Weyl, Vol. 5/3, p 197. 

Zinc chromate is a useful yellow pigment widely used in metal priming paints zinc cyanide is used in electropating the fluoride, ZnF2, is used in the fluorination of organics, in the manufacture of phosphors for fluorescent electric lights, in glazes and enamels for porcelain and in wool preservation. 

Prospects for Selective Fluorination of Organic and Inorganic Species... 

Modern Synthetic Procedures for the Fluorination of Organic Molecules ... 

Novel Methods for Selective Fluorination of Organic Compounds. Design and Synthesis of Fluonnated Antimetabolites Kollonitsch, J hr J Chem 17, 53-59 50... 

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