Bottom-up synthesis of three heterometallic coordination polymers with layered structures constructed from presynthesized [Sb 2(tart) 2] 2− metalloligands

Self-assembly of presynthesized [Sb 2(tart) 2] 2− metalloligand as molecular building block with metal salts affords three unique heterometallic coordination polymers, namely, {[Ln(H 2O) 6][Sb 2(tart) 2]}Cl·5H 2O (Ln = La ( 1), Pr ( 2)) and {[Ba 2(H 2O) 7][Sb 2(tart) 2] 2}·4H 2O ( 3), (tart = tartaric acid). Their structures were determined by single crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, and TG analyses. Compounds 1 and 2 are isostructural and represent the first examples of lanthanide-organic open frameworks containing [Sb 2(tart) 2] 2− metalloligands. The structures of 1 and 2 contain left-handed and right-handed layer, each built up from the same-handed helical chains. Compound 3 consists of two kinds of arm-shaped chiral layers, which alternately stack in a heterochiral fashion to yield a racemic 3D hydrogen-bonded network with 1D channels along the a axis. To the best of our knowledge, compounds 1– 3 are the first 2D chiral layer frameworks constructed from [Sb 2(tart) 2] 2− metalloligands and rare-earth or alkaline-earth metal ions. [Display omitted]