Photoinduced electron transfer from ferrocene

The two intermediates are clearly the result of photoinduced electron transfer from the ferrocene donor to the 6w(arene)iron(lI) acceptor, which constitutes the first reaction step toward deligation (Eq. 37). 

The radical anion 60 can also be easily obtained by photoinduced electron transfer from various strong electron donors such as tertiary amines vide supra), ferrocenes, tetrathiafulvalenes, and thiophenes. In homogeneous systems, back electron transfer to the reactant pair plays a dominant role resulting in an extremely short hfetime of Qo In these cases, no net formation of is observed. These problems were circumvented by Fukuzumi et al. by using NADH analogues as electron donors. - Selective one-electron reduction of Qq to Cjo takes place by the irradiation of Qq in a deaerated benzonitrile solution upon the addition of 1-benzyl-1,4-dihydronicotinamide (BNAH) or the corresponding dimer [(BNA)2] (Scheme 10). The formation of Qq confirmed by the observation of the absorption band at 1080 nm in the NIR spectrum assigned to the fullerene radical anion. 

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