V-shaped dicarboxylate ligands induced structural variation of Zn(II) complexes based on N-heterocyclic ligand from 1D to 3D: Synthesis, structures and luminescence properties

Abstract

In this work, three V-shaped dicarboxylate ligands, 5-tert-butyl isophthalic acid (H2tbip), 5-hydroxyisophthalic acid (H2hip) and 4,4′-carbonyldibenzoic acid (H2cba) were employed as coligands to make a comparison on the structures of Zn(II)-mbbt coordination polymers (mbbt = 1-(2-methylbenzimidazol-1-ylmethyl)benzotriazole). Three new complexes, [Zn2(mbbt)(tbip)2]n (1), {[Zn(mbbt)(hip)(H2O)]·2H2O·mbbt}n (2) and [Zn(mbbt)(cba)]n (3) have been synthesized and characterized. Structural analyses indicate that complex 1 displays a 3D 66 topology based on triangular Zn2(COO)3 SBUs; complex 2 shows an infinite 1D chain; complex 3 presents a 2D 44-sql network based on paddle-wheel-like Zn2(COO)4 SBUs. The structural differences of the three complexes suggest that the V-shaped dicarboxylate ligands can tune the structural dimensionality of Zn(II)-mbbt complexes. Furthermore, the photoluminescence properties of 1–3 were studied in the solid state at room temperature.