Syntheses, crystal structures and photoluminescences of two (4,4) topological coordination networks derived from the flexible bipyridyl ligands

Two new 2D coordination polymers, Ag₄(μ-4,4′-bpp)₃(1,3-bdc)₂]_n · 2nH₂O (1) and Ag(μ-4,4′-bpp)₂ClO₄]_n(2) (4,4′-bpp = 2,2′-bis(4-pyridylmethyleneoxy)-1,1′-biphenylene; 1,3-bdc = 1,3-benzenedicarboxylate) have been synthesized using three-layer diffusion methods. Single-crystal X-ray analyses reveal that they are both extended grid networks of the (4,4) topology. In complex 1, a chain built by Ag(I) centers with T-shaped and linear geometries is further connected by the interesting ligand-unsupported Ag?Ag interactions as well as the conjugated π systems to form an interdigitated 2-D coordination network. The corrugated (4,4) sheets of 2 are packed in the ab planes and stacked along the c direction with the anions occupying the gaps in the squares.