Fluonnation with chlorine

Similar preference in replacement by fluorine of tertiary versus secondary and secondary versus primary hydrogens is observed in the fluonnation of alkanes with chlorine tnfluonde in 1,2-difluorotetrachIoroethane at room temperature (Table 3). Skeletal rearrangements accompany the fluorination [77]... 

Chlorination of alkanes is less exothermic than fluonnation and bromination less exothermic than chlorination Iodine is unique among the halogens m that its reaction with alkanes is endothermic and alkyl iodides are never prepared by lodmation of alkanes... 

The chemical resistance of PTFE is almost universal It resists attack by aqua regia, hot fummg nitnc acid, hot caustic, chlorine, chlorosulfonic acid, and all solvents. Despite this broad chemical resistance, PTFE is attacked by molten alkali metals, ammonia solutions of such metals, chlorine trifluoride, and gaseous fluonne at elevated temperature and pressure PTFE swells or dissolves m certam highly fluonnated oils near its melting point. Specific lists of chemicals compatible with PTFE are available [/.8]... 

Replacement of hydrogen with halogen can be carried out in the alpha position of fluonnated ethers, amines, aldehydes, or nitriles In 2,2,3,4,4,4 hexafluoro-butyl methyl ether, chlorination occurs predominantly at the methyl, however, bromination occurs mostly at the internal position of the fluorobutyl group 13[Pg.372]

Stenc effects are presumably also responsible for the surprising formation of a chlorinated product from reaction of a hindered fluonnated olefin with potassium fluoride and iodine chlonde [116] (equation 18). 

Side chain fluonnated aryl isocyanates are an important group of substances used in the manufacture of biologically active compounds The synthetic routes to the meta- and para trifluoromethylphenyl isocyanates permit the chlorine-fluonne exchange with hydrogen fluoride to proceed under moderate conditions and in a virtually quantitative manner (equation 22)... 

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