Crystal structures of three lead(II) acetate-bridged diaminobenzene coordination polymers
Poly[tris(acetato-κ2O,O′)(μ2-acetato-κ3O,O′:O)tetrakis(μ3-acetato-κ4O,O′:O:O′)bis(benzene-1,2-diamine-κN)tetralead(II)], [Pb4(CH3COO)8(C6H8N2)2]n, (I), poly[(acetato-κ2O,O′)(μ3-acetato-κ4O,O′:O:O′)(4-chlorobenzene-1,2-diamine-κN)lead(II)], [Pb(CH3COO)2(C6H7ClN2)]n, (II), and poly[(κ2O,O′)(μ3-acetato-κ4O,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 PbIIions exhibit hemidirected coordination. The repeating unit in (I) is composed of four PbIIions having O6, O6N, O7and 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 PbIIion in the asymmetric unit that has an O6N coordination sphere. Pb2O2units 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 formingR22(14) rings.