Polyoxometalate associated ion-pair solid based on a crown ether inclusion complex: Synthesis, structure and spectroscopy

A supramolecular complex, in which a mono-protonated ortho-phynelenediamine (OPDAH)+ is included in the cavity of a crown ether (18-crown-6, 18C6) and a tetrabutyalammonium cation are associated with an isopolyanion [Mo6O19]2− resulting in the formation of compound [Bu4N][OPDAH(18C6)][Mo6O19] (1). Compound 1 has been isolated as a single crystalline material at room temperature from MeCNCH3COOH solvent system through a one-pot synthesis that includes OPDA, 18-crown-6 and [Bu4N]2[Mo6O19]. Compound 1 has been characterized through routine spectroscopic analyses (IR, 1H NMR) and elemental analysis including its structural determination through single crystal X-ray crystallography. Crystal data for 1: monoclinic, C2/c, a = 17.5055(10) Å, b = 16.2661(9) Å, c = 37.006(2) Å, β = 94.8510(10)°, V = 10499.7(10) Å3, Z = 8, R1 = 0.0571, wR2 = 0.1214. Extensive supramolecular hydrogen bonding and π-stacking interactions have been observed in the crystal packing of 1.