Dysprosium Chlorocyanoanilate-Based 2D-Layered Coordination Polymers.

A series of two-dimensional (2D)-layered coordination polymers (CPs) based on the heterosubstituted anilate ligand ClCNAn derived from 3-chloro-6-cyano-2,5-dihydroxybenzoquinone and Dy are reported. By changes in the synthetic methods (layering technique, solvothermal or conventional one-pot reactions) and conditions (solvent, concentration, etc.), different types of 2D extended networks could be prepared and structurally characterized. Compounds and , two polymorphs with the formula [Dy(ClCNAn)(DMSO)]·(HO) [ = 7 (), 0 ()], were prepared by a conventional one-pot reaction and recrystallized at different concentrations. Compound , formulated as [Dy(ClCNAn)(DMF)], was prepared by a layering technique, while compound , formulated as {(MeNH)[Dy(ClCNAn)(HO)]·(DMF)·(HO)}, was obtained by a solvothermal method. Compounds and are neutral 2D CPs of the ClCNAn ligand and Dy ions, while presents 2D anionic layers of [Dy(ClCNAn)(HO)] alternating with cationic layers of MeNH ions. These compounds show very diverse networks, with compound forming 2D (8,3) and (4,3) topology with eight- and four-membered rings with square cavities, and , respectively, a 2D (6,3) topology with six-membered rings (a rectangular cavity for and a regular hexagonal cavity for ), and a 2D (4,4) topology with distorted square cavities. In this respect, and represent the first examples of polymorphism in the family of anilate-based CPs. Thermal analysis measurements (differential scanning calorimetry and thermogravimetry) show an exothermic polymorphic transformation from the kinetically stable phase to the thermodynamically stable phase . The magnetic behavior of - very likely indicates depopulation of the levels, while the presence of weak antiferromagnetic coupling between the Dy centers mediated by the anilate bridge cannot be excluded.