Four Cu(II)/Co(II) coordination polymers based on N,N′-di(3-pyridyl)sebacicdiamide: influence of different carboxylate ancillary ligands on structures and properties

Abstract

<p>Four Cu(II)/Co(II) coordination polymers, [Cu(L)(BDC)(H₂O)]·3H₂O (<b>1</b>), [Cu(L)(DNBA)₂] (<b>2</b>), [Co(L)₂(DNBA)₂] (<b>3</b>), and [Co(L)(NIPH)(H₂O)]·H₂O (<b>4</b>) (H₂BDC = 1,4-benzenedicarboxylic acid, HDNBA = 3,5-dinitrobenzoic acid, H₂NIPH = 5-nitroisophthalic acid, L = N,N′-di(3-pyridyl)sebacicdiamide), have been synthesized under hydrothermal conditions. The structures of <b>1</b>–<b>4</b> have been determined by single-crystal X-ray diffraction analyses and <b>1</b>–<b>4</b> were further characterized by infrared spectroscopy and thermogravimetric analyses. Complex <b>1</b> is a 2-D polymeric layer with a 4-connected <i>sql</i> topology. Complex <b>2</b> displays a 1-D zigzag chain. Complex <b>3</b> possesses a 1-D double-chain structure. Complex <b>4</b> exhibits a ribbon chain based on the 1-D [Co–L]_n<i>meso</i>-helical chain. Adjacent layers for <b>1</b> and adjacent chains for <b>2</b>–<b>4</b> are further linked by hydrogen bonding or <i>π</i>–<i>π</i> stacking interactions to form 3-D supramolecular networks. The differences of carboxylates and metal ions show significant effect on the ultimate architectures of the four complexes. Thermal stabilities, fluorescent properties and photocatalytic activities of <b>1</b>–<b>4</b> were also studied.</p