Adaptive Self-Assembly of Lanthanide-Covalent Organic Polyhedra: from Triangular Prism to Octahedron

An adaptive self-assembly strategy has been used to prepare different lanthanide-covalent organic polyhedra (LnCOPs), where a covalent organic cage was transformed into triangular prism-shaped LnCOPs in the presence of La^III and an unprecedented octahedral complex was obtained upon coordination to Eu^III accompanied by conformational and component changes of the parent organic cage. Importantly, the octahedral organic backbone cannot be synthesized directly from organic subcomponents without metal as the templates. Due to good luminescence properties, selective luminescent anion recognition was achieved by the Eu^III octahedron.