Construction of Train-Like Supramolecular Structures from Decamethylcucurbit[5]uril and Iso- or Hetero-Keggin-Type Polyoxotungstates

A family of inorganic−organic hybrid solid materials has been assembled from presynthesized organic decamethylcucurbit[5]uril (Me10Q[5]) macrocycles and the well-known inorganic polyoxometalate (POM) clusters. Three compounds, formulated as [Na6(H2O)11(Me10Q[5])2]·[β-H2W12O40]·5H2O (1), [Na4(H2O)7(Me10Q[5])2]·[α-SiW12O40]·20H2O (2), and [Na4(H2O)7(Me10Q[5])2]·[β-SiW12O40]·13H2O (3) are reported. In the molecular structures of the three compounds, versatile Keggin-type polyoxotungstate clusters were successfully assembled as inorganic building blocks to build hybrid materials with Me10Q[5]. Compound 1 comprises β-Keggin-type iso-polyoxotungstate [H2W12O40]6− clusters and Me10Q[5]. Compound 2 contains α-Keggin-type [SiW12O40]4− heteropolyanions and Me10Q[5], whereas compound 3 is constructed from β-Keggin-type heteropolyoxosilicotungstate clusters [SiW12O40]4− and Me10Q[5]. All of the compounds feature train-like structural subunits based on central POM/alkali metal backbones and two side rows of parallel Me10Q[5] macrocycles.