Examples of Fragmentations by Photoinduced ET

The fragmentation of radical anions and the reverse reaction, the addition of anions to radicals, are the critical steps of SRN1 reactions [110] which constitute perhaps the largest class of fragmentation reactions initiated by photoinduced electron transfer. These reactions are chain processes and photoinduced ET is involved only in the initiation step, which is usually poorly defined. The reactions may also be initiated by other means, not involving absorption of a photon. The SRN1 reactions and related redox-activation processes have been recently extensively reviewed [72a, 110,127] and will not be discussed here. 

There are also several reviews dealing with various facets of fragmentation reactions in photogenerated radical ions [7-11] as well as more general reviews touching on that subject [1-4]. The examples discussed below were arbitrarily chosen to illustrate certain fundamental and practical aspects summarized in the previous sections. 

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