Katarzyna Grubel - Hexanickel Enediolate Cluster Generated in an Acireductone Dioxygenase Model Reaction

Version 1

      Publication Details (including relevant citation   information):

      Rudzka, K.; Grubel, K.; Arif, A. M.; Berreau, L. M. Inorganic   Chemistry 2010, 49, 7623-7625;

      DOI: 10.1021/ic100775m


        Abstract Image 

        A nickel(II) enediolate cluster (2) forms upon     treatment of     [(6-Ph2TPA)Ni(PhC(O)C(OH)C(O)Ph)]ClO4    (1) with Me4NOH·5H2O in     CH3CN. Crystallographic studies of     2 revealed a hexanuclear structure of     S6 symmetry with a formula of     {[Ni(PhC(O)C(O)C(O)Ph)(CH3OH)]·1.33CH3OH}6.     Because isolation of bulk amounts of 2 from     the reaction involving 1 proved impossible, a     solvation analogue of 2 (labeled     5) was generated from admixture of     Ni(ClO4)2·6H2O,     2-hydroxy-1,3-diphenylpropane-1,3-dione, and     Me4NOH·5H2O in     CH3OH/CH3CN. Complex 5    is formulated as     {[Ni(PhC(O)C(O)C(O)Ph)(H2O)]·H2O·0.25CH3CN}6    based on elemental analysis, a molecular weight determination,     UV−vis, and a magnetic moment measurement. Treatment of     5 with O2 and 6-Ph2TPA     (6 equiv) results in the formation of CO and     [(6-Ph2TPA)Ni(O2CPh)2(H2O)]     (3), the latter of which was isolated in 69%     yield. The level of 18O incorporation in this     reaction matches that for a reaction wherein 2    is generated from 1. These results provide     evidence that a nickel(II) enediolate cluster is the     O2 reactive species in a previously reported model     reaction for nickel(II)-containing acireductone dioxygenase.  

      Address (URL): http://pubs.acs.org/doi/abs/10.1021/ic100775m