Series of Cd(II) and Pb(II) Coordination PolymersBased on a Multilinker (R,S-)2,2'-Bipyridine-3,3'-dicarboxylate-1,1'-dioxide.

Sixnew metal-organic frameworks (MOFs) with structuresranging from a one-dimensional (1D) chain, two-dimensional (2D) layer, even 2D double layer to three-dimensional (3D) network based on 2,2'-bipyridine-3,3'-dicarboxylate-1,1'-dioxide(H2bpdado) and N-donor ligands (1,2-bis(4-pyridyl)ethane(bpa) or 1,2-trans-bis(4-pyridyl)ethene (bpe)),namely, [Cd(bpdado)(H2O)2]n(1), {[Cd2(bpdado)2(bpa)(H2O)2]·DMF·3H2O}n(2), {[Cd2(bpdado)2(bpe)(H2O)2]·8.5H2O}n(3), {[Pb2(bpdado)2(bpa)]·10H2O}n(4), {[Pb2(bpdado)2(bpe)]·10H2O}n(5), [Pb2(bpdado)Cl2(H2O)2]n(6), were synthesized by hydro(solvo)thermal and/or diffusionmethods. In these complexes, the bpdado ligand shows four types of coordination modes, three of which appeared for the first time. Polymers 1-6present diverse motifs with differentmetal ions and different conformations and/or coordination modes ofbpdado, which may show a natural synergy in structural diversity ofthe resultant MOFs. Under the similar synthetic conditions just withdifferent metals (Cd(II) and Pb(II)), 6exhibits a 2Dcovalent grid layer, whereas complex 1displays a 1Dchain. Meanwhile, Cd(II) atom in 1shows an unprecedentedtriangular prism coordination geometry. Although bpe/bpa ligands actas pillars between 2D [M(bpdado)]nlayersubunits in complexes 2-5, the Cd(II)-basedcomplexes 2and 3are extended into a 3Dlayered-pillared network, while the Pd(II)-based complexes 4and 5just exhibit the 2D double layers. Moreover, the 2D [Cd(bpdado)]nlayer subunits of 2and 3can be derived from replacing hydrogenbonds in 1D 1with coordination bonds dependent on differentcoordination modes of bpdado. In addition, the solid-state luminescence(for 1-6) and gas adsorption properties(for 2and 3) have been studied and discussedin detail. [ABSTRACT FROM AUTHOR]