Synthesis and polymerization of fluorinated monomers bearing a reactive lateral group. Part 6 - synthesis of trifluorovinyl epoxide and its 1,2-diol

The preparation of the new omega-epoxide and 1,2-dihydroxy trifluorovinyl m onomers useful as comonomers in the copolymerization of commercially availa ble alkenes is presented. The addition of 1-iodo-1,2-dichloro-1,2,2-trifluo roethane to allyl acetate led quantitatively to the expected chlorotrifluor inated-2-iodo-1-acetate which underwent a thermal rearrangement yielding RF ClCH2CH(OAc)CH2I even in the presence of a radical initiator that started t o decompose at mild temperature. Whatever the amount of rearranged product, both these iodoacetates formed epoxides in alkali media giving two new com pounds GRAPHICS and GRAPHICS in high yields. Dechlorination yielded the tri fluorovinyl epoxide GRAPHICS (in 40% yield) and side products from the ring opening of the oxirane group. The mixture of halogenated epoxides was quan titatively hydrolysed into the halogenated -1,2-diol which was dechlorinate d into F2C=CFCH2CH(OH)CH2OH in 58% yield. All these products and intermedia tes were characterized by H-1,F-19 and C-13 NMR spectroscopy. (C) 1999 Else vier Science S.A. All rights reserved.