Pyrene-dihydrophenazine bis(radical cation) in a singlet ground state.

Org Lett

Department of Chemistry, Graduate School of Science, Osaka City University, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan.

Published: July 2009

A new pyrene-dihydrophenazine dyad was prepared. Oxidation of the neutral species produced a bis(radical cation) species, which was characterized by the absorptions of their component radical cations in the visible region. A thermally accessible triplet state was observed in the ESR measurement in frozen n-PrCN. The energy gap between the singlet and triplet states was determined to be 2J/k(B) = -36 +/- 3 K.

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http://dx.doi.org/10.1021/ol9009927DOI Listing

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