Six heterometallic coordination polymers containing cobalt(II): Syntheses, crystal structures and magnetic properties

Six new coordination polymers, [Co(NiL)(aipt)] (1), [Co2(ML)(hipt)2(CH3OH)(H2O)]·CH3OH (M = Cu (2), Ni (3)), [Co2(C2O4)2(CuL)2] (4), [Co4(NiL)4(ipt)4(H2O)2] (5) and [Co(CuL)(tpt)] (6) (H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien; H2aipt = 5-aminoisophthalic acid; H2hipt = 5-hydroxyisophthalic acid; H2ipt = isophthalic acid; H2tpt = terephthalic acid), have been synthesized by a solvothermal method and characterized by single-crystal X-ray diffraction. Complexes 1, 4 and 5 exhibit different infinite chain structures formed by CoNi (1), Co2Cu2 (4), Co4Ni4 (5) units, respectively, via oxamide and diverse carboxylate bridges, while complexes 2, 3 and 6 exhibit different two-dimensional network structures formed by Co2M or Co2M2 units via oxamide and 5-hydroxyisophthalate or terephthalate bridges. The results of magnetic determination show weak antiferromagnetic interactions in 1–3 and 5–6, and the spin–orbit coupling interaction of Co(II) is a primary factor in the magnetic behaviors.

Graphical abstractSix heterometallic coordination polymers containing cobalt(II), CoNi (1), Co2Cu (2), Co2Ni (3), Co2Cu2 (4), Co4Ni4 (5) and CoCu (6), have been synthesized with macrocyclic oxamide and aromatic multicarboxylate (including aipt2−, hipt2−, ipt2− and tpt2−) ligands, structurally determined and magnetically studied.Figure optionsDownload full-size imageDownload as PowerPoint slide