A series of 1D, 2D and 3D coordination polymers based on a 5-(benzonic-4-ylmethoxy)isophthalic acid: syntheses, structures and photoluminescence

Abstract

Seven new coordination polymers, namely, [Zn(HL)(H₂O)] (1), [Zn(HL)(phen)]·1.5H₂O (2), [Zn(HL)(L¹)] (3), [Zn₂(HL)₂(L²)₂]·2H₂O (4), [Zn(HL)(L³)_0.5] (5), [Zn(HL)(L⁴)] (6) and [Cu₂(L)(OH)(H₂O)]·0.5H₂O (7) (H₃L = 5-(benzonic-4-ylmethoxy) isophthalic acid, phen = 1,10-phenathroline, L¹ = 1,2-bis(1,2,4-triazole-1-yl)ethane, L² = 1,3-bis(1,2,4-triazole-1-yl)propane, L³ = 1,6-bis(1,2,4-triazole-1-yl)hexane and L⁴ = 4,4′-bis(1,2,4-triazole-1-ylmethyl)biphenyl), have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction. In compounds 1–6, the H₃L ligand is partially deprotonated to form HL²⁻, while it is completely deprotonated in 7. Compound 1 shows a 3D framework with 4-connected (4²·7·8³)₂ topology. Compound 2 displays a 1D ribbon structure. The neighboring ribbons are further linked by hydrogen-bonding interactions to form a 3D supramolecular architecture. Compound 3 exhibits a 2D undulated sheet. The sheets are further penetrated into each other to give rise to a 3D polycatenation structure. Compound 4 displays a 2D supramolecular layer structure. Compound 5 shows a 3D (3,6)-connected (4·8)(4·8²·10³) net. Compound 6 reveals a 3D four-fold interpenetrating diamondoid architecture. Compound 7 displays a (3,8)-connected (4·6²)(4⁴·6⁸·8¹²·10⁴) topology. These compounds have been characterized by powder X-ray diffractions (PXRD) and thermal gravimetric analyses (TGA). In addition, the photoluminescent behaviours of 1–6 have been investigated in detail.