Three new extended Preyssler-type polyoxometalates modified by transition metal-2,2′-biimidazole complexes

Three extended Preyssler-type ({P5W30}) polyoxometalates modified by transition metal (TM)-2,2'-biimidazole (abbreviated as H(2)biim) complexes, namely [Mn(H(2)biim)(3)](5)H-2[Wn(H(2)biim)(2)(H2O)} (NaP5 W30O110)]center dot 39H(2)O (1), [{(H(2)biim)(2)Zn(mu-OH)Zn(H(2)biim)(mu-H(2)biim)Zn(H(2)biim)(H2O)}(2)H-4(NaP5W30O110)]center dot 22H(2)O (2), and {(H(4)biim)(18)NaH5[mu-Fe(H(3)biim)(H2O)(3))(mu-Fe(H2O)(4))(NaP5W30O110)(2)](2)center dot 78H(2)O}(n) (3) have been hydrothermally synthesized, and characterized by physicochemical and spectroscopic methods. Their catalytic activities have been investigated. 1 contains mono-supporting {P5W30) anions. In compound 2, a (P(5)w(30)) anion is bi-supported by two symmetrical chains constructed by trinuclear zinc complexes. Compound 3 is composed of infinite 1-D zigzag chains built up of (P5W30) polyoxoanions linked via [Fe(H2O)(4)](3+) and [Fe(H(3)biim(H2O)(3)](4+) fragments. H(2)biim ligands adopt three coordination modes in the structure. All these compounds have 3-D supramolecular frameworks via extensive hydrogen-bonding interactions. (C) 2012 Elsevier Inc. All rights reserved.