Halide assisted formations of polymeric ethylenediaminetetraacetato lead(II) complexes
Insoluble isomers of lead(II) ethylenediaminetetraacetates [Pb2(edta)(H2O)]2n (1), [Pb4(edta)2]n·2nH2O (2) and allomers Pbn[Pb(edta)Pb(H2O)X]2n·2nH2O(X = Cl, 3; Br, 4) are isolated from the reactions of lead nitrate with ethylenediaminetetraacetic acid in acidic solution (H4edta = ethylenediaminetetraacetic acid). The four complexes have been full characterized by elemental analysis, FT-IR spectra, thermogravimetric analyses, solid state 13C NMR spectra and X-ray crystal structure analyses. Topological analyses of complexes 2 and 3(4) show unusual (6, 8)-connected 2-nodal and (4, 5, 6)-connected 3-nodal network topologies respectively. The insertions of chloride and bromidein3 and 4 give new examples of polymeric lead-edta complexes. The products 3 and 4 obtained at room temperature show an obvious effect of halide assistance formation of insoluble ethylenediaminetetraacetato lead(II) complexes which is supported by solid state NMR and X-ray crystal structure analyses.