Triplet Recombination of Radical Ion Pairs

In the context of the potential Cope rearrangement of hexa-1,5-diene radical cations (Section 2.4.1), we mentioned the triplet recombination of radical ion pairs generating a biradical [202, 203]. Because of continuing interest in this type of reaction we briefly mention two additional examples involving radical cationic systems discussed in this review, viz., the isomeric 1,2-diphenylcyclopropane radical cations, cis- and trans- 3 , and norbornadiene radical cation, 91 +. 

H. D. Roth, Biradicals by Triplet Recombination of Radical Ion Pairs , Photochem. Photobiol. Sci., 2008, 7, 540. 

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