Structure Versatility of Coordination Polymers Constructed from a Semirigid Tetracarboxylate Ligand: Syntheses, Structures, and Photoluminescent Properties

Based on a semirigid tetracarboxylate ligand 5-(3,5-dicarboxybenzyloxy)­isophthalic
acid (H4DBIP), 11 coordination polymers formulated as [M2DBIP­(H2O)4(μ2-H2O)]·6H2O [M = Mg (1), Co (2)], [Cd3(DBIP)2]·(Me2NH2)2·(H2O)3 (3), [Cd2DBIP­(H2O)2DMA]·5DMA·5H2O (4), (InDBIP)·(Me2NH2)·3DMA·2H2O (5), and (LnDBIP)·(Me2NH2)·(H2O)2 [Ln = Eu
(6), Gd (7), Tb (8), Dy (9), Ho (10), and Yb (11)] (Me2NH2+ = dimethylammonium cation; DMA
= N,N-dimethylacetamide) were synthesized
under solvothermal conditions and characterized by single-crystal
X-ray structural, thermogravimetric, and photoluminescent studies.
Compounds 1–2 are isomorphous and
feature 2-fold interpenetrating dia networks. Compound 3 possesses a rare (4,8)-connected anionic network with flu topology built from 8-connected [Cd3(COO)8] clusters and 4-connected DBIP4– ligands.
Compound 4 is a 3D framework with pts topology
based on 4-connected rectangular DBIP4– ligands.
Compound 5 shows a 3D anionic framework with lon topology. Compounds 6–11 display
a 6-connected uninodal net with msw topology. In the
11 structures, the ligand H4DBIP exhibits two different
conformations owing to its flexibility, serving as 4-connected or
6-connected nodes in the resultant structures. Luminescent properties
have also been investigated.