Co(II) Metal−Organic Frameworks (MOFs) Assembled from Asymmetric Semirigid Multicarboxylate Ligands: Synthesis, Crystal Structures, and Magnetic Properties

Abstract

A series of four new coordination polymers, namely, [Co(HL 1 )(μ-4,4 0 -bpy)(H 2 O) 3 ] n 3 (4,4 0 -bpy 4), have been assembled from four asymmetric semirigid multicarboxylate ligands 3-(4-carboxy-phenoxy)phthalic acid (H 3 L 1 ), 3-(2-carboxy-phenoxy)-phthalic acid (H 3 L 2 ), 4-(2-carboxy-phenoxy)-phthalic acid (H 3 L 3 ), and 4-(4-carboxyphenoxy)-phthalic acid (H 3 L 4 ) with the help of 4,4 0 -bipyridine (4,4 0 -bpy) ligand. X-ray single crystal diffraction analysis reveals that compound 1 displays a one-dimensional (1D) zigzag chain structure constructed from 4,4 0 -bpy ligands and partly deprotonated L 1 ligands, which further forms a three-dimensional (3D) supramolecular architecture via hydrogen bonds. Complex 2 possesses a two-dimensional (2D) layered architecture composed of continuous trinuclear Co(II) clusters. Complex 3 also shows a 2D molecular framework assembled from alternate tetranuclear and dinuclear Co(II) clusters bridged by 4,4 0 -bpy or L 3 ligands, and complex 4 exhibits a 3D (4,4)-connected self-penetrating network constructed from ladder-like and fishbone-like subunits. Magnetic studies indicate the spin-orbit coupling of isolated Co(II) in 1 and the overall antiferromagnetic interaction in 2-4.

Design and construction of self-penetrating coordination frameworks

“…*) 3 [47] Annotations: * Please refer to [1] and [2] for the detailed description and interpretation. [31] (H 2 pht = phthalate, dpa = 4,4′-dipyridylamine, H 2 oba = 4,4′-oxybis(benzoate), bix = 1,4-bis(imidazol-1-ylmethyl)benzene, sip = 5-sulfoisophthalic acid monosodium salt, H 3 cpp = 4-(4-carboxyphenoxy)phthalic acid, bpy = 4,4′-bipyridine). Complex 18 shows a chiral self-penetrating 4-connected yyz net, generating from interlocking homochiral [Cd(H 2 O)(dpa)] n 2n+ double helices and [Cd(pht)] n single helices (Fig.…”

4,4′-(Pyridine-2,5-diyl)dibenzoic acid as a building block for Cd(II) and Mn(II) coordination compounds: Synthesis, structural features and properties

“…Various coordination polymers or metal-organic frameworks (MOFs) have shown a multitude of versatile architectures and topological motifs [5][6][7][8], accompanied with desirable properties and potential applications in various fields ranging from luminescence, molecular magnetism and catalysis to selective gas absorption and separation systems [2,[9][10][11][12]. Many multi-carboxylate or heterocylic carboxylic acids have been designed and used as building blocks for the preparation of functional coordination polymers or MOFs [1,2,6,7,10,[12][13][14][15]. In particular, we and others have reported a diversity of coordination compounds with intriguing architectures and interesting properties based on carboxylic acid building blocks [13][14][15][16][17][18][19][20][21][22][23][24].…”

Syntheses, Structures and Luminescent Properties of Three new Zinc(II) Complexes Constructed from Dicarboxylate and N-donor Coligands

“…Most studies were focused on rigid carboxylate ligands [30][31][32][33]. Metal-organic polymers containing semirigid multicarboxylate have been less reported [34][35][36]. Semi-rigid V-shaped multicarboxylate ligands, which contain two benzene rings as a central molecular framework and bridged by a nonmetallic atom (C, O, S, or N atom), are excellent ligands.…”