A series of organic–inorganic hybrid compounds formed by [P2W18O62]6− and several types of transition metal complexes

Abstract

Five new organic–inorganic hybrid compounds based on [P₂W₁₈O₆₂]⁶⁻ (abbreviated as {P₂W₁₈}) and several types of transition metal complexes (TMCs) have been synthesized and characterized by IR, UV-Vis, XRD, cyclic voltammetry measurements and single crystal X-ray diffraction analysis. [Cu(phen)₂][Cu(phen)(H₂O)₃][Cu(phen)₂(H₂O)][P₂W₁₈O₆₂]·8H₂O (1) (phen = 1,10-phenanthroline) is a {P₂W₁₈} bi-supported complex of phen, while [Cu(2,2′-bpy)(H₂O)₂]₂[Cu(2,2′-bpy)₂][P₂W₁₈O₆₂]·3.5H₂O (2) (2,2′-bpy = 2,2′-bipyridine) is a 1-D chain structure formed by {P₂W₁₈} and copper complexes of 2,2′-bpy. [Ag(2,2′-bpy)₂]₅[HP₂W₁₈O₆₂]·H₂O (3), [Ag(2,2′-bpy)(H₂O)]₂[Ag(2,2′-bpy)]₂[Ag₂(2,2′-bpy)₃][P₂W₁₈O₆₂] (4), and [Ag(2,2′-bpy)(H₂O)]₃[Ag₂(2,2′-bpy)₃][Ag(2,2′-bpy)][P₂W₁₈O₆₂]·H₂O (5) are constructed from {P₂W₁₈} and silver complexes of 2,2′-bpy. Compounds 4 and 5 are novel dimers of {P₂W₁₈} joined by silver complexes, while compound 3 contains two different kinds of silver complexes, forming a novel supramolecular structure. Each of the five compounds is formed by {P₂W₁₈} and more than one type of TMC. The formation mechanism of these compounds has been carefully discussed. In addition, we also synthesized two supramolecular structures based on {P₂W₁₈} and organic moieties: [H₆P₂W₁₈O₆₂](phen)_5.5 (6) and [H₆P₂W₁₈O₆₂](phen)₃·43H₂O (7). The catalytic properties of these compounds were also tested.