Incorporation of Clathrochelate-Based Metalloligands in Metal–Organic Frameworks by Solvent-Assisted Ligand Exchange

Iron(II) cage complexes with terminal 4-pyridyl groups can be incorporated in metal–organic frameworks (MOFs) via solvent-assisted ligand exchange (SALE). Paddle-wheeled MOFs with N,N′-di-4-pyridylnaphthalenetetracarboxydiimide pillars were used as starting materials. Pillar exchange was nearly quantitative, despite the fact that the cage complexes are long (∼15 A) and sterically demanding. The reactions provide products of high crystallinity, and the structures of daughter MOFs were determined by single crystal X-ray diffraction. The crystallographic analyses showed that some of the SALE experiments led to topological changes of the MOF structures.