Katarzyna Grubel - “Synthesis, Characterization and Photoinduced CO-release Reactivity of a Pb(II) Flavonolate Complex; Comparisons to Group 12 Analogs

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      Publication Details (including relevant citation   information):

      Grubel, K.; Saraf, S.; Anderson, S. N.; Laughlin, B. J.; Smith,   R. C.; Arif, A. M.; Berreau, L. M. Inorganica Chimica   Acta 2013, 407, 91-97.


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      The synthesis, characterization, and photoinduced CO-release   reactivity of [(6-Ph2TPA)Pb(3-Hfl)]ClO4  (1;   6-Ph2TPA = N,N-bis((6-phenyl-2-pyridyl)methyl)-N-((2-pyridyl)methyl)amine;   3-Hfl = anion of 3-hydroxyflavone) is reported and   compared with Group 12 analogues   ([(6-Ph2TPA)M(3-Hfl)]ClO4  (M = Hg(II) (2),   Cd(II) (3), Zn(II)   (4)). The Pb(II) complex   exhibits unique features within this group of complexes in terms   of its structural and spectroscopic features involving the   coordinated flavonolate ligand. Similar to the Group 12   compounds, irradiation of 1 at   300 nm in an O2-containing environment results in   the quantitative release of CO and the formation of a Pb(II)   O-benzoylsalicylate (O-bs, depside) complex via   a photoinduced dioxygenase-type reaction. Comparison of the   quantum yield for the reaction of the Pb(II) flavonolate complex   (Φ = 0.21(6)) versus the reactions of the   structurally-related Group 12 metal complexes   (6-Ph2TPA)M(3-Hfl)]ClO4  (M = Hg(II) (2,   Φ = 0.31(2)), Cd(II) (3, Φ = 0.28(2)), Zn(II)   (4), Φ = 0. 09(1))   revealed that flavonolate complexes of a heavy metal ion (Cd(II),   Hg(II), Pb(II)) exhibit a higher reaction quantum yield than the   Zn(II) derivative. Both Pb(II) and Zn(II) flavonolate complexes   were found to be catalysts for the oxidative photoinduced   degradation of 3-hydroxyflavone. The combined results of these   investigations suggest that metal contaminants typically present   in soil, including toxic heavy metal ions, might facilitate the   oxidative decomposition of plant-derived flavonols via   photoinduced reactions.

      Address (URL): http://www.sciencedirect.com/science/article/pii/S0020169313004003