Three 2-(4-thiazolyl)benzimidazole-based supramolecular assemblies oriented by Keggin and Wells–Dawson anions

Abstract

Three polyoxometalate supramolecular assemblies based on rigid 2-(4-thiazolyl)benzimidazole (L) and two types of polytungstate anions, [CuII2Cl(L)4(PW12O40)]·3H2O (1), [CuII(L)2(H2O)]2[P2W18O62]·(HL)2·6H2O (2), and [ZnII(L)3]4[H(KPW12O40)3] (3), have been synthesized and characterized by single-crystal X-ray diffraction, elemental analyses, and IR spectra. Compound 1 contains binuclear copper clusters {Cu2L4Cl}3+ with Cl– as bridges. These binuclear clusters and [PW12O40]3– anions construct a supramolecular 2-D layer through hydrogen-bonding interactions. In 2, the [CuL2(H2O)]2+ subunits and Wells–Dawson anions build a 1-D supramolecular chain. In 3, the [PW12O40]3– anions are covalently linked by K+ to form an inorganic chain. These chains and discrete [ZnII(L)3]2+ subunits construct a 3-D supramolecular structure. The electrochemical and photocatalytic properties of 1–3 have been studied.