From Trigonal Bipyramidal to Platonic Solids: Self-Assembly and Self-Sorting Study of Terpyridine-Based 3D Architectures

摘要

Using a series of tritopic 2,2∶6′,2″-terpyridine (tpy) ligands constructed on adamantane, three discrete 3D metallo-supra-molecular architectures were assembled, i.e., trigonal bipyramidal,tetrahedron, and cube. The self-assembly used tritopic ligands as corner directing units and metal ions as glue units at the edge. The angles of the linkers between adamantane and tpy head play a critical role in guiding the assembled structures, which have the general formula of M_(3n)L_(2n),where M denotes metal ion and L denotes ligand. All complexes were fully characterized by ~~1H, ~(13)C NMR, diffusion-ordered NMR spectros-copy, ESI-MS, and traveling-wave ion mobility-mass spectrometry. The binary mixtures of LA and LC or LB and LC underwent a self-sorting process that led to the self-assembly of discrete 3D structures. The self-sorting behavior is solely based on the angles precoded within the arm of tritopic ligands. Moreover, kinetic study of preassembled cube and tetrahedron demonstrated a slow ligand exchange process toward a statistical mixture of hetero tetrahedrons with LA and LB.