The reactivity of triplet phenalenone (PN) towards typical H- and electron-donors is characterized by means of nanosecond laser flash-photolysis. H-abstraction from tributylstannane occurs with a rate constant of ca. 5×105 M-1 s-1. From the activation energy for this reaction, an upper limit for the T2-T1 energy gap is calculated as 9±1 kJ mol-1 in nonpolar solvents, consistent with the solvent-insensitive high ΦT value in phenalenone. Triplet phenalenone also reacts via photoinduced electron transfer with 1,4-diazabicyclo[2.2.2]octane (DABCO) with rate constant close to the diffusional control limit. The spectrum of the solvated free radical anion of phenalenone has a maximum at 440 nm in acetonitrile.
|Número de páginas||4|
|Publicación||Journal of Photochemistry and Photobiology A: Chemistry|
|Estado||Publicada - 15 abr 2004|