Application of trimethylvinylsilane as a convenient synthetic precursor of(Perfluoroalkyl)ethenes: An unusual fluoride-induced elimination-desilylation coupled reaction
Z. Szlavik et al., Application of trimethylvinylsilane as a convenient synthetic precursor of(Perfluoroalkyl)ethenes: An unusual fluoride-induced elimination-desilylation coupled reaction, ORG LETT, 2(15), 2000, pp. 2347-2349
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A convenient and effective method for the preparation of perfluoroalkylated
ethenes is described. First, the free radical addition of perfluoroalkyl i
odides to trimethylvinylsllane in the presence of AlBN gave iodoethylsilane
intermediates (F(CF2)(n)CH2CHISiMe3, n = 4 (1), 6 (2), 8 (3), 10 (4); 94-9
9%). Then an unusual dehydrohalogenation-desilylation reaction was effected
by tetrabutylammonium fluoride, and finally the product isolation (F(CF2)(
n)CH=CH2 (5-8), 62-87%) was facilitated using a fluorous phase separation t
echnique. This novel approach can also be applied to adjust short C-2 hydro
carbon units to functionalized fluorinated segments (e.g., HOCH2(CF2)(8)CH=
CH2 (11), 71%), All structures were verified by state-of-the-art multinucle
ar one- and two-dimensional NMR experiments involving both homo- (F-19-F-19
) and heteronuclear (H-1-C-13, F-19-C-13) correlations based on the GMQFCOP
S and inverse H-1 and/or F-19 detected GHSQC, GHMQC sequences with broad-ba
nd adiabatic C-13 decoupling.