Use of Chain Transfer Agents in Addition-Fragmentation

Among several radical techniques, the free-radical addition-fragmentation chain transfer reaction appears to be an unrivaled method for the synthe- 

This process is schematically identical to a classic atom transfer reaction because of the termination of the polymer chain and the reinitiation of a new one. Thus, as a first approach, it is possible to apply the classical Mayo equa- 

The CTAs which follow the addition-fragmentation [58,59] mechanism are of particular interest in organic and polymer chemistry. Recently, many studies have shown that allyl, acrylyl, and allenyl transfers to alkyl halides represent powerful synthetic tools to prepare sophisticated molecules. 

The preparation of such CTAs involves a nonnegligible part of organic chemistry. The functional end groups of the oligomers obtained may be further modified into others by classic reactions to extend the potentially available end fragments. 

Few monomers have been studied in addition-fragmentation polymerization. Mainly styrene, acrylate, and methacrylates have been used so far in addition-fragmentation to obtain telechelic oligomers. As an example, styrene and methyl methacrylate (MMA) [60,61] were polymerized through an addition-fragmentation process, using allylic sulfides as CTAs (entries 12 

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