Four complexes with a bulky carboxylate ligand: syntheses, crystal structures, and luminescent properties

Abstract

Four complexes of 3,3-diphenylpropanoate (L) and 4,4 0 -bipyridine as auxiliary bridging ligands were synthesized and characterized, namely [Zn(L) 2 (4bpy)-(EtOH) 2 ] ? (1), [Co(L) 2 (4bpy)(EtOH) 2 ] ? (2), [Ni(L) 2 (4bpy)-(EtOH) 2 ] ? (3), and [Cu(L) 2 (4bpy)(H 2 O)] ? (4) (4bpy = 4,4 0 -bipyridine). X-ray single-crystal diffraction analyses show that complexes 1-4 all take one-dimensional (1D) fishbone-like structures incorporating bridging 4bpy ligands. The complexes show different supramolecular frameworks interlinked via intermolecular hydrogen bonds, pÁÁÁp stacking, and/or C-HÁÁÁp supramolecular interactions. Complex 3 only has a simple one-dimensional fishbonelike chain, whereas complexes 1 and 2 show two-dimensional supramolecular structures by interchain C-HÁÁÁO hydrogen bonds. Complex 4 is assembled into twodimensional layers and then an overall three-dimensional framework by a combination of interchain O-HÁÁÁO hydrogen bonds and C-HÁÁÁp supramolecular interactions. The luminescent properties of the ligands and their complexes were investigated.