Syntheses, structures, and fluorescent properties of two helical complexes based on a long rigid N-heterocyclic ligand

A three-dimensional Pb(II) coordination framework: poly[[μ4-(E)-2,2'-(diazene-1,2-diyl)dibenzoato]dimethanollead(II)]

In the title coordination polymer, [Pb(C14H8N2O4)(CH3OH)2]n, the asymmetric unit contains half of a Pb(II) cation, half of a 2,2'-(diazene-1,2-diyl)dibenzoate dianionic ligand (denoted L(2-)) and one methanol ligand. Each Pb(II) centre is eight-coordinated by six O atoms of chelating/bridging carboxylate groups from four L(2-) ligands and two O atoms from two terminal methanol ligands, forming a distorted dodecahedron. The [PbL2(MeOH)2] subunits are interlinked via the sharing of two carboxylate O atoms to form a one-dimensional [PbL2(MeOH)2]n chain. Adjacent chains are further connected by L(2-) ligands, giving rise to a two-dimensional layer, and these layers are bridged by L(2-) linkers to afford a three-dimensional framework with a 4(12)6(3) topology.