Metal Organic Nanocapsules as Two-Dimensional Network Building Blocks

Metal–organic frameworks (MOFs) are a class of porous materials with a wide variety of applications, including molecular adsorption and separation. Recently, the first MOF based on the zinc-seamed pyrogallol[4]­arene nanocapsule as a secondary building unit was reported. The zinc-seamed nanocapsules are linked together with 4,4′-bipyridine, which is a divergent ligand commonly used in the synthesis of MOFs. In an effort to identify other likely candidates for nanocapsular linking, electronic structure calculations were performed to determine energetic and geometric properties of (Zn­(C₂O₂H₃)₂)_1,2Y model complexes, which have been shown previously to reliably model the zinc coordination sphere found in the nanocapsules. Here, Y represents one of 17 divergent ligands with N, S, or O electron-donating atoms. MOFs were synthesized and characterized from two of the ligands suggested as most suitable for further experimental study.