Organofluoro Compounds

A few examples of the existence of fluorinated organic compounds are used as illustration of a problem area. 

A series of dibenzo[l,4]dioxins bearing nitro and trifluoromethyl substituents in one ring and chlorine in the other was synthesized for comparison with impurities in commercial samples of the lampricide 3-trifluoromethyl-4-nitrophenol, and to assess their ability to induce MFO activity (Hewitt et al. 1998). Although they appeared to be relatively weak inducers, there were other unidentified components that were highly active. 

Adriaens P, Q Fu, D Grbic-Galic (1995) Bioavailability and transformation of highly chlorinated dibenzo-p-dioxins and dibenzofurans in anaerobic soils and sediments. Environ Sci Technol 29 2252-2260. 

Adriaens P, TM Vogel (1995) Biological treatment of chlorinated organics. In Microbial transformation and Degradation of Toxic Organic Chemicals. (Eds LY Young and CE Cerniglia), pp. 435-486. Wiley-Liss, New York, USA. 

Albrecht ID, AL Barkovskii, P Adriaens (1999) Production and dechlorination of 2,3,7,8-tetrachIorodibenzo-p-dioxin in historically-contaminated estuarine sediments. Environ Sci Technol 33 131-lAA. 

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We have recently reported ( ) several synthetic studies of weak nucleophile SnAr reactions. In the latter cases (26f-1), new synthetic methodology was reported for the direct introduction of fluoroalkoxy groups into a variety of aromatic systems. These reports represent synthetically useful procedures for obtaining some otherwise inaccessible fluoroalkoxy materials but, unfortunately, they require the use of a dipolar, aprotic solvent (usually hexamethylphosphoramide, HMPA) and, in some cases, elevated temperatures. However, because of their diverse and important applications ( ), the syntheses of these and other organofluoro compounds continue to be of interest. For example, two recent reports of useful fluoroalkoxy materials include the insecticide activity exhibited by fluoroalkoxy substituted 1,3,4-oxadiazoles... 

For thermochemical calculations, at least, fluoroorganics present special problems, e.g. Bond D (2007) J Org Chem 72 7313, and references therein note p. 7322 Difficulties in obtaining consistent and accurate data are found even with the simplest of the organofluoro compounds, fluoromethane. ... 

Sodium fluoride is utilized in the manufacture of organofluoro-compounds (halogen exchange reaction), as a preservative, and as a source of fluorine for toothpaste additives (sodium monofluorophosphate). 

Bomb fusion with alkali has been applied66 to the determination of fluorine in organofluorosilicon compounds. It is recommended that the-large amount of alkali present after the decomposition of the organofluoro compound is removed by the use of a cationite. The test solution followed by water is passed through a column of SDV-3 ion-exchange resin and the combined solution is titrated with standard thorium nitrate solution, using Alizarin red S indicator. 

The enantioselective organocatalytic fluorination using organofluoro nucleophiles and selective fluoroalkylation of organic compounds by tackling the negative fluorine effect " have been reviewed. 

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