A rare alb-4,8-Cmce metal–coordination network based on tetrazolate and phosphonate functionalized 1,3,5,7-tetraphenyladamantane

Abstract

Symmetric tetrahedral ligands are prominent, but somewhat under-investigated building blocks for the generation of coordination polymeric networks. Coordination networks [Mn₅Cl₂(L¹)₂(H₂O)₄(DMF)₄]·3H₂O·7DMF, 1 and the [La₂(H₅L²)₂(H₂O)₆], 2 are synthesized under mild solvothermal methods in DMF from the adamantane-based tetrahedral ligands, 1,3,5,7-tetrakis(4-phenyltetrazol-5-yl)adamantane (H₄L¹), reported for the first time, and 1,3,5,7-tetrakis(4-phenylphosphonic acid)adamantane (H₈L²), respectively. Compounds 1 and 2 are based on completely different pentanuclear and binuclear secondary metal building units, respectively, and have different symmetries, but demonstrate an interesting coincidence of underlying topologies, which could be interpreted as a directing or ‘imprinting’ effect of the symmetry of the rigid tetrahedral ligands. Both structures represent examples of a rarely observed (4,8)-coordinated net. The χ_MT product for 1 at room temperature is slightly lower than the expected for five Mn(II) ions with S = 5/2 and g ≈ 1.98 and on lowering the temperature χ_MT approaches the expected value for a single Mn(II) as a result of the antiferromagnetic coupling through the tetrazolate bridges.