From dissymmetrical mononuclear entities to centrosymmetrical heterotrinuclear complex with 2D supramolecular structure: synthesis, characterization, crystal structure, and magnetic properties

A new centrosymmetrical heterotrinuclear complex, {[Cu(oxbe)]2Co(H2O)2}·2DMF·DMA with 2D supramolecular structure, has been obtained by the self-assembly of a dissymmetrical building block [Cu(oxbe)]− with bivalent metal ion Co2+, where H3oxbe is dissymmetrical ligand N-benzoato-N′-(2-aminoethyl)oxamido, DMF=dimethylformamide, DMA=dimethylamine. Its structure was determined by single crystal X-ray analysis. The molecular structure is centrosymmetrical with the cobalt atom lying on an inversion center. Through the hydrogen bonds and d–π stacking interactions, a 2D supramolecular structure is formed. This study exemplifies a new method for the assembly of supramolecular structure using a dissymmetrical brick. Magnetic susceptibility measurements (5–300 K) indicate that the central cobalt and terminal copper metal ions are antiferromagnetically coupled with J=−23.1 cm−1.