Diverse Entangled Metal-Organic Framework Materials Incorporating Kinked Organodiimine and Flexible Aliphatic Dicarboxylate Ligands:Synthesis,Structure,Physical Properties,and Reversible Structural Reorganization

摘要

Hydrothermal synthesis has afforded a family of divalent metal adipate (adp) coordination polymers incorporating the kinked dipodal organodiimine 4,4'-dipyridylamine (dpa).As revealed by single-crystal X-ray diffraction,the structures of these materials are critically dependent on the metal coordination geometry,the carboxylate binding modes,and the conformations of the flexible adipate moieties.In all cases,hydrogen-bonding interactions imparted by the dpa tethers also play a structure-directing role.All materials were further characterized via infrared spectroscopy and elemental and thermogravimetric analysis.[Co(adp)(dpa)] (1) displays doubly interpenetrated three-dimensional (3-D) networks with a decorated a-Po-type (pcu) topology.In contrast,[Ni(adp)(dpa)(H2O)] (2) possesses a triply interpenetrated binodal cooperite-type (pts) framework,the highest level of interpenetration yet reported for this structure type.[Zn(adp)(dpa)]·H2O (3) presents mutually inclined polycatenated 2-D graphitic layers consisting of neutral dimeric [Zn2(mu_2-adp)2] kernels conjoined by dipodal dpa ligands.Compound 1 exhibited weak antiferromagnetic coupling between its carboxylate-bridged Co atoms,following Curie-Weiss behavior with O=-3.3 K.Compound 3 manifested blue light emission under ultraviolet excitation,as well as a reversible structural reorganization upon dehydration/rehydration.