Functionalized Pentamolybdodiphosphate-Based Inorganic–Organic Hybrids: Synthesis, Structure, and Properties

Three inorganic–organic hybrid compounds based on functionalized pentamolybdodiphosphonopropionate anion [(HO2CC2H4PO3)2Mo5O15]4–, [Co3(bipy)4(H2O)6{(HO2CC2H4PO3)2Mo5O15}2]·(H2bipy)2·18H2O (1), [Fe3(bipy)4(H2O)6{(HO2CC2H4PO3)2Mo5O15}2]·(H2bipy)2·18H2O (2), and [Cu­(bipy)­(H2O)2{(HO2CC2H4PO3)2Mo5O15}]·(H2bipy)·4H2O (3), where bipy = 4,4′-bipyridine, have been successfully synthesized at different pH values in aqueous solutions. In compound 1, [(HO2CC2H4PO3)2Mo5O15]4– acts as a tridentate ligand and coordinates to the Co2+ ions of trimeric complex cations [Co3(bipy)4(H2O)6]6+ forming a layer. In 3 [(HO2CC2H4PO3)2Mo5O15]4– acts as a bidentate ligand and coordinates to the Cu2+ ions of complex chains [Cu­(bipy)­(H2O)2]n2n+, forming a different layer from that in 1. The three compounds were characterized by elemental analysis, IR spectra, and TGA. In addition, their fluorescent properties and magnetic properties have also been investigated.