Selected Rate Data for Reactions of Heteroatom-Centered Radicals

Tabic 3.10 Selected Rate Data for Reactions of Heteroatom-Centered Radicals 

Most studies have concerned the kinetics of arenethiyl radicals with monomers including S and its derivatives468 47 and MMA.469,473 The radicals have electrophilic character and add more rapidly to electron-rich systems (Tabic 3.10). Relative reactivities of the monomers towards the ben/.oy Ithiyl radical have also been examined.453 

It is established that the initial reaction involves predominantly tail addition to monomer.473 There is no evidence that abstraction competes with addition. It should be noted that the addition of arenethiyl radicals to double bonds is readily reversible. 

A study on the kinetics of the reactions of phenylseleno radicals with vinyl monomers has also been reported.464 

Phosphinyl radicals (e.g. 103-107) arc generated by photodecomposition of acyl phosphinates or acyl phosphine oxides (see 3.3.4.LI)282,466 474,473 or by hydrogen abstraction from the appropriate phosphine oxide.467 

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