Crystal structures of three lead(II) acetate-bridged di­amino­benzene coordination polymers

摘要

Poly[tris­(acetato-κ² O,O′)(μ2-acetato-κ³ O,O′:O)tetra­kis­(μ3-acetato-κ⁴ O,O′:O:O′)bis­(benzene-1,2-di­amine-κN)tetra­lead(II)], [Pb4(CH3COO)8(C6H8N2)2]n, (I), poly[(acetato-κ² O,O′)(μ3-acetato-κ⁴ O,O′:O:O′)(4-chloro­benzene-1,2-diamine-κN)lead(II)], [Pb(CH3COO)2(C6H7ClN2)]_n, (II), and poly[(κ² O,O′)(μ₃-acetato-κ⁴ O,O′:O:O′)(3,4-di­amino­benzo­nitrile-κN)lead(II)], [Pb(CH₃COO)₂(C₇H₇N₃)]_n, (III), have polymeric structures in which monomeric units are joined by bridging acetate ligands. All of the Pb^II ions exhibit hemidirected coordination. The repeating unit in (I) is composed of four Pb^II ions having O₆, O₆N, O₇ and O₆N coordination spheres, respectively, where N represents a monodentate benzene-1,2-di­amine ligand and O acetate O atoms. Chains along [010] are joined by bridging acetate ligands to form planes parallel to (10-1). (II) and (III) are isotypic and have one Pb^II ion in the asymmetric unit that has an O₆N coordination sphere. Pb₂O₂ units result from a symmetry-imposed inversion center. Polymeric chains parallel to [100] exhibit hydrogen bonding between the amine and acetate ligands. In (III), additional hydrogen bonds between cyano groups and non-coordinating amines join the chains by forming R ₂ ²(14) rings.