Structure extension in two Pb(II)–sulfonate complexes from hemidirected to holodirected Pb(II) by secondary Pb–O interactions

•Two Pb(II) complexes containing ortho-hydroxylbenzenesulfonates are first reported.•The secondary Pb-O bonds play important role during the network assembly.•Secondary Pb-O interactions perform hemi- to holodirected spheres for Pb(II).•The ortho-hydroxyl group enrich the coordination modes of the –SO3 group.

Two novel Pb(II) complexes, [Pb(HL1)(2,2′-bpy)(MeOH)]n, (HL1 = 2-hydroxyl-5-methyl-1,3-disulfonate dianion) (1) and [Pb1.5(OH)(L2)]n, (L2 = 2-hydroxyl-5-nitro-benzenesulfonate dianion) (2), involving ortho-hydroxyl arenesulfonic acids, have been synthesized and characterized for the first time. Complex 1 exhibits helical chain motif with hemidirected Pb(II) spheres, while complex 2 presents layer motif with rarely mixed hemidirected and holodirected Pb(II) spheres. Considering the secondary PbO bonds, the two complexes are extended to layer and 3-D pillared layered framework with holodirected Pb(II) spheres.

Graphical abstractTwo new Pb(II)–sulfonate complexes have been obtained, which exhibit structure extension through the modulation of Pb(II) geometry from hemidirected to holodirected tuned by secondary PbO bonds.Figure optionsDownload full-size imageDownload as PowerPoint slide