| Autor: |
Loftus, Lauren M., White, Jessica K., Albani, Bryan A., Kohler, Lars, Kodanko, Jeremy J., Thummel, Randolph P., Dunbar, Kim R., Turro, Claudia |
| Předmět: |
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| Zdroj: |
Chemistry - A European Journal; Mar2016, Vol. 22 Issue 11, p3704-3708, 5p |
| Abstrakt: |
The new complex [Ru(pydppn)(biq)(py)]2+ ( 1) undergoes both py photodissociation in CH3CN with Φ500=0.0070(4) and 1O2 production with ΦΔ=0.75(7) in CH3OH from a long-lived 3ππ* state centered on the pydppn ligand (pydppn=3-(pyrid-2-yl)benzo[ i]dipyrido[3,2- a:2′,3′- c]phenazine; biq = 2,2′-biquinoline; py=pyridine). This represents an order of magnitude decrease in the Φ500 compared to the previously reported model compound [Ru(tpy)(biq)(py)]2+ ( 3) (tpy=2,2′:6′,2′′-terpyridine) that undergoes only ligand exchange. The effect on the quantum yields by the addition of a second deactivation pathway through the low-lying 3ππ* state necessary for dual reactivity was investigated using ultrafast and nanosecond transient absorption spectroscopy, revealing a significantly shorter 3MLCT lifetime in 1 relative to that of the model complex 3. Due to the structural similarities between the two compounds, the lower values of Φ500 and ΦΔ compared to that of [Ru(pydppn)(bpy)(py)]2+ ( 2) (bpy=2,2′-bipyridine) are attributed to a competitive excited state population between the 3LF states involved in ligand dissociation and the long-lived 3ππ* state in 1. Complex 1 represents a model compound for dual activity that may be applied to photochemotherapy. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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