Syntheses, crystal structures, and luminescent properties of three zinc carboxyphosphonates with 2D layered and 3D pillared-layer structures

• Three new zinc(II) carboxyphosphonates with 2D and 3D structures have been synthesized.
• The in situ esterification reaction took place between one carboxylate and ethanol/methanol in two compounds.
• The luminescent properties of the compounds have been investigated.

Three zinc(II) carboxyphosphonates [Zn3(5-pmipe)2]·0.5H2O (1·0.5H2O), [Zn3(5-pmipm)2]·H2O (2·H2O), and [Zn3(5-pmipH)2(bpy)0.5]·6H2O (3·6H2O) (5-pmipH4 = 5-(phosphonomethyl)isophthalic acid, 5-pmipeH3 = [C6H3(CO2H)(CO2Et)(CH2PO3H2)], 5-pmipmH3 = [C6H3(CO2H)(CO2Me)(CH2PO3H2)], bpy = 4,4′-bipyridine) were synthesized under hydrothermal conditions. Compounds 1 and 2 are isostructural. In compounds 1 and 2, the {ZnO4} and {CPO3} tetrahedra are interconnected into a zigzag infinite chain via corner-sharing. In addition, these chains are further linked by carboxyphosphonate ligands into a 2D layer. Interestingly, one carboxylate group experiences an in situ esterification reaction with ethanol and methanol, respectively. Compound 3 displays a 3D pillared-bilayer open framework structure. The {ZnO4}, {ZnO3N} and {CPO3} tetrahedra are interlinked through corner-sharing into one chain, which are joined together by 5-pmipH3− into a bilayer. The layers are pillared up by bpy into 3D network. The luminescent properties of compounds 1–3 were investigated in solid state at room temperature.

Three zinc(II) carboxyphosphonates were synthesized under hydrothermal conditions. The luminescent properties of compounds 1–3 were investigated in solid state at room temperature.Figure optionsDownload as PowerPoint slide