Solvents and auxiliary ligands co-regulate three antiferromagnetic Co(II) MOFs based on a semi-rigid carboxylate ligand.

By reacting an asymmetry semi-rigid Y-shaped/L-shaped linker H3cpta (H3cpta = 3-(4'-carboxyphenoxy)phthalic acid) and Co(CH3COO)2·6H2O under different N-donor ligands in different solvents, three new Co-based coordination polymers, [Co3(cpta)2(bpe)3(H2O)4] (1) [Co(μ2-H2O)(μ3-OH)(Hcpta)(bpe)(H2O)·3(DMF)3(H2O)] (2) and [Co3(cpta)2(bpa)4] (3) have been obtained. They exhibit trinodal topological nets/layer, based on Co(2+) ions and Y-shaped/L-shaped carboxylate linkers. 1 and 3 present 3D frameworks with the point symbol {4·10(2)}2{10(5)·12}{4·8(5)}2 for 1 and {4·8(2)}2{8(5)·9}{4·6(7)·9(2)}2 for 3. While, 2 exhibits a 2D layer with the point symbol {4·6·8}{4·6(2)·8(3)}{6(2)·8}. The magnetic studies indicate that all of the three complexes show antiferromagnetic exchanges transmitted through μ3-carboxylate/μ4-carboxylate bridges, μ2-H2O molecules and μ3-OH ions between Co(2+) ions, respectively. And the result of this research shows that the solvent and the secondary ligands could co-regulate coordination polymer with interesting properties, providing a constructive guidance when synthesizing versatile topologies with the same organic spacer but a different architecture.