Cation-exchange-induced single-crystal-to-single-crystal transformations of a nanoporous coordination complex

Use of a rigidly conjugated clamp-like bis-pyridyl-bis-amide ligand N,N-bis-(3-pyridyl)isophthalamide (L), complex [CoLCl2]2 (1) with porous macrocycle structure was obtained under solvothermal conditions. When single crystals of 1 were immersed into the methanol solution of HgCl2 and CdSO4, new crystals of a bimetallic macrocyclic complex [HgLCl2]2 (2) and a two-dimensional (2D) corrugated sheet complex [CdLSO4(H2O)2]n (3) were attained, respectively. All these phenomena are observed through single crystal to single crystal (SCSC) transformations along with the metal–ligand bond breaking and the new metal–ligand bond formation. In addition, the determination of Scanning Electron Microscope (SEM) and Energy-Dispersive X-ray Spectrometry (EDS) reveals that the exchange is a recurrent dissolving-exchange-crystallization process of solvent-mediated mechanism.