Abstract
Three supramolecular complexes, [VO(phen)(C2O4)(H2O)]·CH3OH (1) [(VO)2(u2-C2O4)(C2O4)2(H2O)2]·L·H2O (2), and [(4,4′-bipyH2)0.5]+[VO2(2,6-dipic)]−·2H2O (3) (phen = 1,10-phenanthroline 4,4′-bipy = 4,4′-bipyridine, 2,6-dipic = 2,6-pyridinedicarboxylic, L = 1,4-bis((3,5-dimethyl-1H-pyrazol-1-yl)methyl)benzene), have been prepared and characterized by elemental analysis, IR, and UV–vis spectroscopy and single-crystal diffraction analysis. Structural analysis shows that the three complexes all contain carboxylate and V=O moiety; vanadium of 1 and 2 are six coordinate with distorted octahedral geometry with N2O4 and O6 donor sets, respectively, while 3 is five coordinate with distorted trigonal bipyramidal geometry with a NO4 donor set. The complexes exhibit catalytic bromination activity in the single-pot reaction for the conversion of phenol red to bromophenol blue in H2O–DMF at 30 ± 0.5 C with pH 5.8, indicating that they can be considered as functional model vanadium-dependent haloperoxidases. In addition, electrochemical behaviors are also studied.
Acknowledgements
This study was supported by the grants of the National Natural Science Foundation of China (No. 21071071) and Dr start Foundation of Liaoning province in China (No. 20111067) for financial assistance.