Structure and Magnetic Property of A pcu Cobalt(II) Network Constructed with Mixed-Clusters and V-shaped Ketone Ligand

The V-shaped ketone ligand, benzophenone-2,4′-dicarboxylic acid (H2bpdc), was used as a long ditopic asymmetric linker to bridge mixed cobalt(II) clusters into a three-dimensional pcu network, namely [Co7(μ3–OH)2(bpdc)6(2,2′-bpy)4]·2H2O (1) (2,2′-bpy=2,2′-bipyridine), which was synthesized by methods of hydrothermal reaction and the crystal structure was determined. The linear trinuclear cluster [Co3(COO)6] and planar tetranuclear cluster [Co4(μ3–OH)2(COO)4] simultaneously appeared in the same compound for the first time. IR, elemental analysis and XRPD confirmed the phase purity of the bulk materials. Magnetic properties of 1 in the 300–2 K have been studied, which reveal the occurrence of antiferromagnetic interactions between Co(II) ions.