Synthesis and characterization of a new class of polyfluorinated alkanes: tetrakis(perfluoroalkyl)alkane

The synthesis and physico-chemical characterization of 1,1,2,2-tetrakis(perfluoroalkyl-methylene)ethane {[F(CF2)(n)CH2](2)CH}(2) (n = 6, TK6; n = 8, TK8) are reported. The synthesis consists of four steps: (1) addition of allyl alcohol to a perfluoroalkyl iodide, F(CF2)(n)I (n = 6, 8) to give the corresponding iodo-adduct; (2) dehalogenation of the adduct by treatment with zinc in aqueous acetic acid, yielding 3-perfluoro-n-alkyl-1-propene; (3) addition of 3-perfluoro-n-alkyl-1-propene to perfluoroalkyl iodide, F(CF2)(n)1 (n = 6, 8) to give 1,3-perfluoro-n-alkyl-2-iodo-propane; (4) coupling of 1,3-perfluoro-n-alkyl-2-iodo-propane by zinc in acetic anhydride giving the final products. TK6 and TK8 are characterized by very low surface tension values and exhibit very good properties as potential ski-waxes. (C) 2002 Elsevier Science B.V. All rights reserved.