Unique Tetradentate Coordination of 2,2′-Bipyridyl-3,3′-Dicarboxylate (bpdc). Hydrothermal Synthesis and Crystal Structure of A Novel Polymeric Supramolecule [Co(bpdc)(H2O)2]n

Abstract

The title complex has been synthesized using hydrothermal methods and its structure determined by X-ray diffraction. It consists of polymeric chains of [Co(bpdc)(H₂O)₂] units (bpdc = 2,2′-bipyridyl-3,3′-dicarboxylate) which are linked by intermolecular hydrogen bonds to form two-dimensional layer-shaped supramolecules. Each bpdc ligand bridges two cobalt(II) centers in a rare tetradentate fashion through its two pyridyl nitrogen atoms chelating to one cobalt and two carboxyl oxygen atoms to the other in the equatorial plane. The octahedral coordination of cobalt is completed by two axial water molecules.