Silver(I)/cobalt(II) complexes with mixed V-shaped polycarboxylate and rod-like N-donor ligands: Syntheses, structures and properties

Four Ag(I)/Co(II) complexes based on a flexible V-shaped ligand 3,3′, 4,4′-diphenylsulfone tetracarboxylic acid (H4dstc), namely [Ag(bpe)2]·H3dstc (1), {[Ag2(H2dstc)(bpp)(H2O)]·H2O}n (2), {[Co2(dstc)(bpe)2(H2O)2]·2H2O}n (3) and {[Co4(dstc)2(bpa)3(H2O)6]·7H2O}n (4) have been synthesized in the presence of different rod-like N-donor ligands 1,2-di(4-pyridyl)ethylene (bpe), 1,3-bis(4-pyridyl)propane (bpp), and 1,2-bis(4-pyridyl)ethane (bpa). In complex 1, the H3dstc– ligand does not take part in coordination but balances the charge by its one deprotonated carboxylate group. Complex 2 contains two different motifs: a cationic 1D chain [Ag(bpp)]+ and an anionic 1D meso-helix [Ag(H2dstc)(H2O)]–. Interestingly, the non-covalent hydrogen bonding interactions extend such simple discrete units or 1D chains into 3D supramolecular architectures. Complex 3 represents a 3D binodal 4-connected (64·82) network, while complex 4 can be simplified as a primitive cubic (pcu) network. In addition, the photoluminescence of 1 and 2 and the magnetism of 3 and 4 are investigated, respectively.