Two modes of formation of carbonium ions from olefins and suitable electron acceptors

Stable organic cation salts: Ion pair equilibria and use in cationic polymerisation

“…Not only do Lewis Acids give rise to these kinetic problems, but also to chemical problems regarding the necessity or otherwise for co-catalyst molecules, and, in this regard, Kennedy (6) has recently tried to crystallise current thinking. Experiments involving low molecular weight model systems have also gone some way to providing an understanding of such catalyst-cocatalyst complexities (7)(8)(9).…”

One‐electron transfer initiated polymerization reactions I. Initiation through monomer cation radicals

“…(46) is indicated as a dication, there is no evidence for difunctionality, i.e., conversion of one chain end to a radical species by reoxidation of the metal salt may result in termination by the latter which is a radical trap. However, the formation of dications from the reaction between an olefin and a metal salt electron acceptor has been confirmed by the reaction of 1,l-diphenylethylene with antimony pentachloride at -80°C in methylene chloride (27). The formation of a dicarbonium ion was demonstrated spectrophotometrically by NMR measurements as well as by the identification of the products of quenching reactions.…”

“…An alternate route for the formation of a carbonium ion is the disproportionation of antimony pentachloride followed by addition to the olefin (27). 2SbC15 SbCla+SbCls-…”

“…However, dimerization of monomer cation radicals has been demonstrated (27) spectrophotometrically and by quenching the reaction mixture from the treatment of a solution of 1,l-diphenylethylene in methylene chloride a t -80°C with a precooled solution of antimony pentachloride in the same solvent.…”

Study of the reaction of interaction of tetracyan ethylene with 1,1‐diphenyl ethylene and its dimers by electronic spectroscopy

“…It was shown that dimerization was possible only in the presence of a cocatalyst (H,O, HCl). SZWARO et al showed that in the presence of SbCl, the product of dimerization is 1,1,4,4-tetraphenyl butadiene-1,3 [2]. It was estimated by them that the reaction proceeded through the stage of single electron transfer and formation of a cation radical of DPHE and subsequent recombination of radicals.…”