Ancillary ligands assisted self-assembly of metal organic frameworks: Synthesis, crystal structures and photophysical properties of two Zn(II) complexes containing in-situ formed tetrazole ligands

摘要

Solvothermal reactions of 4-cyanobenzoic acid (HL~1), NaN3, hydrated ZnSO4 in the presence of ancillary ligands pyrazine or 4,4'-dimethylbipyridine (Me2bpy) afforded a 3-D coordination polymer [Zn(L~2)(H2O)]_n (1) and a 2-D layer [Zn3(Me2bpy)(N3)2{L~2)]n (2) (L~2 = 4-tetrazolylbenzenecarboxylate), respectively in which pyrazine significantly alters the self-assembly of 1 and the coordination of Me2bpy in 2 leads to a novel linearly trinuclear [Zn3(Me2bpy)2(N3)2]~(4+) subunit functioning as a secondary building block (SUB). Their crystal structures have been determined by X-ray crystallography and solid state luminescent properties have been measured at room temperature.