Addition of free radicals to unsaturated systems. Part VII. 1 : 1-Difluoroethylene

Abstract

The photochemical reaction of trifluoroiodomethane with 1 : l-difluoroethylene yields only the compound CF,CH,*CF,I, i.e. , the trifluoromethyl radical attacks exclusively the :CH, group. Proof of constitution is given. Iodine monobromide and 1 : l-difluoroethylene yield only 1-bromo-1 : 1difluoro-2-iodoethane ; the iodo-compound is converted into 1 : 1 : 1-trifluoro-2-iodoethane by means of mercurous fluoride.THE direction of addition of a trifluoromethyl radical, derived from trifluoroiodomethane , to vinyl chloride and vinyl fluoride was shown t o be exclusively to the :CH, group (Part 11, J., 1953(Part 11, J., , 1199. The present study is concerned with the highly polarised olefin 1 : 1difluoroet hylene.Trifluoroiodomethane and 1 : l-difluoroethylene show no dark reaction, but react smoothly on exposure to light of wave-length >3000 A, with liberation of only traces of iodine, to give exclusively CF,*(C,H,F,)*I. Light of wave-length >2200 A (silica reaction vessels) appreciably increases the rate of formation of CF,*(C,H,FJ*I ; small amounts of products of higher boiling point are also formed. Infra-red spectroscopic examination shows that the two products CF,*(C,H,F,)*I are identical. The product is formed by a chain reaction of the type postulated earlier :CF,I -/ CF,.

Photochemically Enabled Iodine Degenerative Transfer Controlled Radical Homo- and Block Copolymerization of Vinylidene Fluoride at Ambient Temperatures with Mn2(CO)10and Visible Light

“…Indeed, high power UV photoinduced telomerizations were described for VDF over 50 years ago (19,77,78). Likewise, we have also confirmed (50,(79)(80)(81)(82) that VDF free radical polymerization (FRP) occurs readily under UV irradiation at rt in the presence of TBPO.…”

Random and sequential radical cotelomerizations of 3,3,3‐trifluoropropene (H2CCHCF3) with vinylidene fluoride (F2CCH2)

“…Few works on photoinitiation and different radical initiators have also been performed. [53][54][55] On the other hand, iodine transfer polymerization (ITP) of VDF with C 6 F 13 I, C 6 F 13 CH 2 CH 2 I or HCF 2 CF 2 CH 2 I, initiated by tert-butylperoxypivalate (TBPPi) has been reported, 56,57 but to our best knowledge no telomerization of VDF with (CF 3 ) 2 CFI has been initiated by TBPPi.…”

Fluorinated cotelomers based on vinylidene fluoride (VDF) and hexafluoropropene (HFP): Synthesis, dehydrofluorination and grafting by amine containing an aromatic ring

“…Perfluoroalkyl iodides or a,v-diiodoperfluoroalkanes act as efficient chain transfer agents (CTA), since they easily undergo CF 2 -I bond cleavage [5,6,9,11,12,14,15,[20][21][22] leading to low molecular weight molecules. Most studies on the direction of addition of the telogen onto the asymmetric monomer (VDF) have shown that the addition mainly occurs onto the methylene groups of VDF [11,15,[20][21][22][23][24][25][26][27], and that it is regioselective.…”

“…The telomerization of vinylidene fluoride has been extensively investigated [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Perfluoroalkyl iodides or a,v-diiodoperfluoroalkanes act as efficient chain transfer agents (CTA), since they easily undergo CF 2 -I bond cleavage [5,6,9,11,12,14,15,[20][21][22] leading to low molecular weight molecules.…”