Structurally Distinct Metal–Organic and H-Bonded Networks Derived from 5-(6-Carboxypyridin-3-yl)isophthalic Acid: Coordination and Template Effect of 4,4′-Bipyridine

5-(6-Carboxypyridin-3-yl)isophthalic acid (H 3 L) was utilized as an almost unexplored multifunctional ligand to construct, under hydrothermal conditions, ten new coordination compounds, namely, [Cd(μ 2 - H 2 L) 2 ] n ( 1 ), [Ni(HL)(H 2 biim) 2 ] ( 2 ), [Mn(μ 2 - HL) (phen)(H 2 O)] 2 ·2H 2 O ( 3 ), {[Mn 3 (μ 4 - L) 2 (H 2 O) 6 ]·3H 2 O} n ( 4 ), {[Co 3 (μ 5 - L) 2 (H 2 O) 6 ]·2H 2 O} n ( 5 ), {[Ni 3 (μ 4 - L) 2 (H 2 O) 6 ]·2H 2 O} n ( 6 ), {[Zn 3 (μ 5 - L) 2 (H 2 O) 4 ]·2H 2 O} n ( 7 ), {[Mn 3 (μ 5 - L) 2 (H 2 O) 6 ]·4H 2 O} n ( 8 ), {[Co 3 (μ 4 - L) 2 (μ 2 -4,4′-bipy)(H 2 O) 6 ]·2H 2 O} n ( 9 ), and {[Ni 3 (μ 5 - L) 2 (H 2 O) 6 ]·2H 2 O} n ( 10 ), also using an optional auxiliary ligand selected from 2,2′-biimidazole (H 2 biim), 1,10-phenanthroline (phen), or 4,4′-bipyridine (4,4′-bipy). The obtained compounds 1 – 10 were analyzed by IR spectroscopy, thermogravimetric and elemental analysis, and single-crystal and powder X-ray diffraction. The structures of the products vary from 3D MOFs (metal–organic frameworks 5 and 7 – 10 ) to 2D CPs (coordination polymers 1, 4, and 6 ) as well as to a discrete 0D monomer 2 and a dimer 3 . The latter two are extended by multiple hydrogen bonds into complex 3D supramolecular networks. This structural difference in 1 – 10 is directed by the kind of metal(II) center, the deprotonation degree of the principal H 3 L building block, and/or the kind of auxiliary ligand. Notably, an addition of 4,4′-bipy can tune the structures of MOFs 8 – 10 by the coordination or template effect. Topological classification of metal–organic and H-bonded underlying networks was performed, disclosing a variety of topological nets: sql (in 1 ), 3,10T3 (in 3 ), 3,4L83 (in 4 and 6 ), tcs (in 5, 8, and 10 ), 3,4,5T95 (in 7 ), and sra (in 9 ), as well as a topologically unique network in 2 . The magnetic properties (for compounds 3 – 6, 8 – 10 ) and luminescent properties (for compounds 1, 7 ) were also investigated and discussed. In fact, compound 7 exhibits an intense violet emission in the solid state. Measurements of the magnetic susceptibility indicate interactions of an antiferromagnetic nature between the adjacent metal(II) centers in the compounds 3 – 6 and 8 – 10 . The obtained products represent the first series of metal–organic compounds assembled from the H 3 L precursor, thus opening up its application as a new pyridine–tricarboxylate organic block for designing CPs or MOFs.