Fluorine synthesis

M.J. Adam, J.M. Berry, L.D. Hall, B.D. Pate, T. Ruth, The cleavage of aryl-metal bonds by elemental fluorine—Synthesis of aryl-fluorides. Can. J. Chem. 61 (1983) 658-660. 

P.W. Collins, R.L. Shone, A.F. Gasieski, W.E. Perkins, R.G. Blanch , Stabilization of a prostaglandin tertiary allylic alcohol system by fluorine Synthesis, acid stability studies and pharmacology of a 16-fluoromethyl analog of SC-46275, Bioorg. Med. Chem. Lett. 2 (1992) 1761-1766. 

The sulfur, selenium, or tellurium in a moderately finely divided state is placed in a copper tube provided with an outlet and inlet. The outlet is connected to a train consisting of a trap cooled in a concentrated hydrochloric acid-ice mixture and then another immersed in liquid air or a solid carbon dioxide-alcohol mixture. Fluorine (synthesis 51) is passed into the inlet at the rate of 1 to 3 1. per hour. The reaction proceeds smoothly. The lower fluorides are condensed to a large extent in the hydrochloric acid-ice cooled trap, and the material collected in the liquid air or solid carbon dioxide trap consists principally of hexafluorides. 

Fluoride ion is not a good leaving group in SRN1 reactions. For instance / - fluoroiodobenzene [66c] and 2-fluoro-3-iodopyridine [67] react with carbanions with retention of fluorine. Synthesis of anti-inflammatory drugs, such as fluorobiprophen 39 can be achieved by reaction of 4-bromo-... 

Differding, E.. and Ofner, H.. /-Fluorobenzenesulfonimide. A practical reagent for electrophilic fluorinations, Synthesis, 187, 1991. 

A purely chemical synthesis of elemental fluorine was achieved by K. O. Christe in 1986 [10] (Scheme 1.1), just in time for the 100 year anniversary of Moissan s first electrochemical fluorine synthesis. Nevertheless, in his paper Christe remarks that all the basic know-how required for this work had already been available 50 years earlier. The key to his simple method is a displacement reaction between potassium hexafluoropermanganate [11] with the strongly fluorophilic Lewis acid antimony pentafluoride at 150 °C. 

Grob U, Kemnitz E, Krishna Murthy J, Rudiger S, Winfield JM. 2006. Sol-gel-fluorination synthesis of amorphous magnesium fluoride. J Solid State Chem 179 739-746. 

Onys ko PP, Kim TV, Kiseleva 01, Rassukana YV, Gakh AA (2009) Cascade iodination-fluorination synthesis of 2-fluorothiophene and 5-fluoro-2-thienyliodonium salts. J Ruor Chem 130 501-504... 

Xu Z-Q, Qui Y-L, Chokekijchai S, Mitsuya H, Zemlicka J (1995) Unsaturated acyclic analogues of 2 -deoxyadenosine and thymidine containing fluorine synthesis and biological... 

Catalysis For technical reasons it can be necessary to have a catalytic active sohd material supported to improve, e.g., its mechanical stability and reduce its flow resistance when used in a flow reactor. The sol-gel fluorination synthesis provides a convenient way for depositing high surface area metal fluorides on supports. For example, HS-AIF3, which as fine powder makes problems when used as catalyst in flow systems, could be supported by Y-AI2O3 whereby its Lewis acidity and consequently its catalytic activity remains almost unchanged [64]. For other catalytic applications, like micro-reactor techniques, deposition of catalytically active thin layers of metal fluorides is also of interest. 

J. L. Delattre, P. J. Chupas, C. P. Grey, A. M. Stacy, Plasma-fluorination synthesis of high surface area aluminum trifluoride from a zeohte precursor, J. Am. Chem. Soc., 123,5364—5365 (2001). 

J.K. Murthy, U. GroB, S. Rudiger, E. Kemnitz and J.M. Winfield, Sol-gel-fluorination synthesis of amorphous magnesiiun fluoride, J. Solid State Chem., 179, 739-746 (2006). 

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