Zinc Metal–Organic Frameworks Based on a Flexible Benzylaminetetracarboxylic Acid and Bipyridine Colinkers

Three new metal–organic frameworks (MOFs), [Zn 2 (L)(H 2 O)] · 3DMF · 1.5H 2 O ( 1 ), [Zn 2 (L)(4,4′‐bpy) 1.5 (H 2 O) 2 ] · 2DMF · 2H 2 O ( 2 ), and [Zn 2 (L)(2,2′‐bpy) 2 (DMF) 2 ] · 2DMF · 4H 2 O ( 3 ) [H 4 L = 5,5′‐(2,3,5,6‐tetramethyl‐1,4‐phenylene)bis(methylene)bis(azanediyl)diisophthalic acid, 4,4′‐bpy = 4,4′‐bipyridine, 2,2′‐bpy = 2,2′‐bipyridine, DMF = N , N ‐dimethylformamide], were synthesized under solvothermal conditions and characterized by single‐crystal X‐ray diffraction analysis, elemental analysis, IR spectroscopy, powder X‐ray diffraction (PXRD), and thermogravimetric analysis (TGA). The L 4– ligands in 1 – 3 display different coordination modes, and the introduction of bipyridine colinkers brings significant structural variation into the frameworks. Complex 1 is constructed from dinuclear carboxylate [Zn 2 O(COO) 4 ] secondary building units (SBUs) and H 4 L ligands and exhibits a binodal (4,4)‐connected pts net with 54.6 % solvent‐accessible void. Complex 2 exhibits an unprecedented tetranodal (3,4,4,4)‐connected net, which is constructed from two types of crystallographically independent Zn II ions, H 4 L ligands, and the 4,4′‐bipyridine colinker. Complex 3 is constructed from parallel 1D molecular ladders stacked along the a axis that generate 1D channels (7.8 × 10.4 Å) and are hydrogen bonded to form 2D layers. The thermal stabilities and luminescence properties of 1 – 3 have also been studied in detail.