Iodination vinyl, with

The poly(vinyl alcohol)-iodine charge transfer complexes have been the subject of many investigations " Water-soluble iodine complexes with ix)ly(l-vinyl-pyrrolidone) are commercially available as disinfecting agents PoIy(N-vinyl car-bazole) polyamides and poly(ethylene oxide) are also found to form molecular addition complexes with iodine and iodine compounds. An account of the different types of molecular complexes formed with various polymers has been published ... 

Vinyl halides add to allylic amines in the presence of Ni(cod)2 where cod=l, 5-cyclooctodine, followed by reduction with sodium borohydride. Aryl iodides add to alkynes using a platinum complex in conjunction with a palladium catalyst. A palladium catalyst has been used alone for the same purpose, and the intramolecular addition of a arene to an aUcene was accomplished with a palladium or a GaCl3 catalyst, " AUcyl iodides add intramolecularly to aUcenes with a titanium catalyst, or to alkynes using indium metal and additives. The latter cyclization of aryl iodides to alkenes was accomplished with indium and iodine or with Sml2. " ... 

Polymer B is that prepared with perfluoroisopropyl iodide it can be considered to have terminal iodine on one side (mono-iodide-copolymer). Polymer C is that prepared with 1,4-di-iodo-perfluorobutane it can be considered to have terminal iodines on both sides (di-iodide-copolymer). In the cases of polymer B and C, it is found that the gel fractions of thier vulcanizates are increased using various kinds of multifunctional vinyl compounds, and that triallyl iso-cyanurate(TAIC) is the most effective coagent. On the other hand, no gel is found in the case of vulcanizates prepared from polymer A even it was cured using TAIC. These experimental results suggest the terminal iodines react with TAIC and form gel. 

Chlorine, bromine, and iodine react with alkenes to give the three-membered ring halonium ion, which reacts with the halide nucleophile to give trans dichlorides, dibromides, or diiodides. Alkynes react to give vinylhalonium ions that lead to vinyl dihalides 14,15,16,17,18,19, 20, 21, 22, 64, 73, 74, 75, 82, 83, 98,108. HOCl and HOBr react with alkenes to give halohydrins 23, 24, 75, 82, 83. 

Povidone-iodine is a water-soluble powder containing approximately 10% iodine complexed with poly(vinyl p5m olidone). It is stable in acid solutions but decomposes when heated above 40°G. It is very active against both gram-positive and gramjiegative bacteria and is thus widely used as a skin antiseptic (1% available iodine) for hand disinfection and for disinfection of clinical devices. 

The majority of preparative methods which have been used for obtaining cyclopropane derivatives involve carbene addition to an olefmic bond, if acetylenes are used in the reaction, cyclopropenes are obtained. Heteroatom-substituted or vinyl cydopropanes come from alkenyl bromides or enol acetates (A. de Meijere, 1979 E. J. Corey, 1975 B E. Wenkert, 1970 A). The carbenes needed for cyclopropane syntheses can be obtained in situ by a-elimination of hydrogen halides with strong bases (R. Kdstcr, 1971 E.J. Corey, 1975 B), by copper catalyzed decomposition of diazo compounds (E. Wenkert, 1970 A S.D. Burke, 1979 N.J. Turro, 1966), or by reductive elimination of iodine from gem-diiodides (J. Nishimura, 1969 D. Wen-disch, 1971 J.M. Denis, 1972 H.E. Simmons, 1973 C. Girard, 1974),... 

The observation in 1949 (4) that isobutyl vinyl ether (IBVE) can be polymerized with stereoregularity ushered in the stereochemical study of polymers, eventually leading to the development of stereoregular polypropylene. In fact, vinyl ethers were key monomers in the early polymer Hterature. Eor example, ethyl vinyl ether (EVE) was first polymerized in the presence of iodine in 1878 and the overall polymerization was systematically studied during the 1920s (5). There has been much academic interest in living cationic polymerization of vinyl ethers and in the unusual compatibiUty of poly(MVE) with polystyrene. 

Stoicescu and Dimonie103 studied the polymerization of 2-vinylfuran with iodine in methylene chloride between 20 and 50 °C. The time-conversion curves were not analysed for internal orders but external orders with respect to catalyst and monomer were both unity. Together with an overall activation energy of 2.5 kcal/mole for the polymerization process, these were the only data obtained. Observations about the low DP s of the products, their dark colour, their lack of bound iodine and the presence of furan rings in the oligomers, inferred by infrared spectra (not reported), completed the experimental evidence. The authors proposed a linear, vinylic structure for the polymer, and a true cationic mechanism for its formation and discussed the occurrence of an initial charge-transfer complex on the... 

It is to be noted that N-vinylcarbazole (NVC) undergoes also living cationic polymerization with hydrogen iodide at —40 °C in toluene or at —78 °C in methylene chloride and that in this case no assistance of iodine as an activator is necessary 10d). NVC forms a more stable carbocation than vinyl ethers, and the living propagation proceeds by insertion between the strongly interacting NVC-cation and the nucleophilic iodide anion. 

The rate of polymerization of vinyl 2-ethylhexyl ether catalyzed by iodine is proportional to [/2] [M] in accordance with an initiation-rate-controlling process... 

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