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 H(3)cpta (H(3)cpta = 3-(4'-carboxyphenoxy)phthalic acid) and Co(CH3COO)(2)center dot 6H(2)O under different N-donor ligands in different solvents, three new Co-based coordination polymers, [Co-3(cpta)(2)(bpe)(3)(H2O)(4)] (1) [Co(mu(2)-H2O)(mu(3)-OH)(Hcpta)(bpe)(H2O)center dot 3(DMF)(3)(H2O)] (2) and [Co-3(cpta)(2)(bpa)(4)] (3) have been obtained. They exhibit trinodal topological nets/layer, based on Co2+ 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 mu(3)-carboxylate/mu(4)-carboxylate bridges, mu(2)-H2O molecules and mu(3)-OH ions between Co2+ 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.