| Autor: |
Matias, Tiago A., Rein, Francisca N., Rocha, Reginaldo C., Formiga, André Luiz Barboza, Toma, Henrique E., Araki, Koiti |
| Předmět: |
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| Zdroj: |
Dalton Transactions: An International Journal of Inorganic Chemistry; 3/7/2019, Vol. 48 Issue 9, p3009-3017, 9p |
| Abstrakt: |
Significant differences were found in the proton-coupled redox chemistry and catalytic behavior of the binuclear [{Ru(H2O)(bpz)}2(tpy2ph)](PF6)4 complex [bpz = 2,2′-bipyrazine; tpy2ph = 1,3-bis(4′-2,2′:6′,2′′-terpyridin-4-yl)benzene] as compared with the structurally analogous derivative with 2,2′-bipyridine (bpy) instead of bpz. The differences were assigned to the stronger π-accepting character of bpz relative to bpy as the ancillary ligand. The expectation of a positive shift for the Ru-centered redox potentials was confirmed for the lower oxidation state species, but that trend was reversed in the formation of the high-valence catalytic active species as shown by a negative shift of 0.14 V for the potential of the [RuIV/V=O] process. Moreover, DFT calculations indicated a significant decrease of about 15% on the spin density and oxyl character of the [RuV=O]3+ fragment. The significantly lower kcat(O2) for the bpz system was attributed to these combined electronic effects. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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