Trifluorovinyl ether

HFPO reacts with a large number of acyl fluorides in a general reaction to give 2-alkoxytettafluotoptopionyl fluorides which in turn may be converted to trifluorovinyl ethers (eq. 14). 

Tetrafluoroethylene undergoes addition reactions typical of an olefin. It bums in air to form carbon tetrafluoride, carbonyl fluoride, and carbon dioxide (24). Under controlled conditions, oxygenation produces an epoxide (25) or an explosive polymeric peroxide (24). Trifluorovinyl ethers,... 

Trifluorovinyl Halides and Ethers. Trifluorovinyl halides are quite commonly encountered reagents, while trifluorovinyl ethers have increased interest as novel monomers.3 There is a nice recent paper dealing with the NMR spectra of some trifluorovinyl ethers.4 Fluorine data for a couple of examples of halides, ethers, and thioethers are given in Scheme 6.30. 

Methyl trifluorovinyl ether, b.p. 10.5- 12.5°C, prepared from tetrafluoroethylene and sodium methoxide [1], has considerable explosive potential. On ignition, it decomposes more violently than acetylene and should be treated with extreme caution [2], Other trifluorovinyl ethers are similarly available from higher alkoxides [1], and although not tested for instability, should be handled carefully. Presence of fluoro-haloalkanes boiling lower than the ether stabilises the latter against spark-initiated decomposition in both fluid phases [3],... 

This chemistry was also performed on one trisphenol, 1,1,1 -tris(4-hydro-xyphenyl)ethane (THPE). The resulting tris(trifluorovinyl ether) monomer forms a thermoset polymer upon curing. 

Figure 3.3. Synthesis of trifluorovinyl ether monomers and perfluorocyclobutane aromatic ether polymers.

A variety of polymer compositions that use this type of polymerization chemistry can be envisioned. In addition to the polyarylate homopolymers that have been described in this chapter, random or block copolymers can be prepared with reasonable ease by the combination of different monomers or oligomers. These compositions can be designed to optimize thermal, mechanical, dielectric, or optical properties of a polymer system. Also, the trifluorovinyl ether functionality can be incorporated into other high-performance polymer systems with relative ease.34,35 The perfluorocyclobutane polyarylate chemistry is a versatile approach to the preparation of high-performance polymers, which is just beginning to demonstrate its utility. 

The polymerization occurs by ionic addition of OH groups to trifluorovinyl ethers although additions of nucleophiles to fluorinated olefins are well known, few examples of additions to trifluorovinyl ethers have been reported15 and no polymerizations by this method have been described. ... 

After isolation, the intermediate products were reacted with zinc in acetonitrile or a glyme solvent to provide the trifluorovinyl ether monomers. This reaction with zinc is also sensitive to the presence of protic substances in the reaction mixture, and forms the same tetrafluoroethyl ether by-product in an undesirable side reaction. The reaction of the 2-bromotetrafluoroethyl ether reactants with zinc involves the formation of zinc organometallic species as an intermediate, and this species is sensitive to hydrolysis by water or acidic substances (Figure 3.6). 

Partially fluorinated PEMs based on trifluorostyrene and a trifluorovinyl ether derivative. 

Trifluorostyrene-based monomers and fheir derivatives are known to exhibit dimerization preferentially over polymerization in confrasf to fhe hydrocarbon analogue slyrene. Eord, DesMarfeau, and Smifh, Smifh and Babb,i i and Smith et al. have advantageously used this behavior to produce 6 (where E can be a large number of differenf spacer groups buf also typically be sulfonamide-based) via cyclopolymerization of multifunctional monomers bearing at least two trifluorovinyl ether units. The polymers themselves have perfluorocyclobutane (PFCB) rings as part of the main chain. 

Perpall, M. W., Smith, D. W., Jr., DesMarteau, D. D. and Greager, S. E. 2006. Alternative trifluorovinyl ether derived fluoropolymer membranes and functionalized carbon composite electrodes for fuel cells. Journal of Macromolecular Science Part C Polymer Reviews 46 297-313. 

Methyl 4-(trifluorosulfonyloxy)but-2-enoate, see 3-Methoxycarbonylpropen-2-yl trifluoromethanesulfonate, 2346 Methyl trifluorovinyl ether, 1098... 

Some terminal polyfluoroalkenes and trifluorovinyl ethers can be converted into corresponding iodides using this procedure ... 

Reaction of 1,1,2-trifluorovinyl ether 166 with 2,2 -iminodiethanol leads to 1,4,7-dioxazocane system 168 (Scheme 43 <1999ZPK1345, 2000JFC13>). The proposed mechanism involves addition of amine to substrate, formation of oxazolinium intermediate 167 via intramolecular nucleophilic cyclization and fluoride a-elimination, and final intramolecular O-alkylation/ring expansion. 

Examples of this type of reaction are the formation of heptafluoropropyl trifluorovinyl ether (12) and perfluoro(l-methylpropyl) triffuorovinyl ether (13). 

Perfluoro(l-nicthylpropyl) Trifluorovinyl Ether (13) Typical Procedure ... 

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