Solvent-Dependent Self-Assembly of Hydrogen-Bonded Organic Porphyrinic Frameworks

Three hydrogen-bonded organic frameworks (HOFs) (HOF-26, HOF-27, HOF-28) have been crystallized from a benzonitrile-based porphyrinic organic linker 4,4',4 '',4'''-(porphyrin-5,10,15,20-tetrayptetrabenzonitrile (PTTBN), in ethylbenzene, nitrobenzene, and tetrahydrofuran, respectively, and structurally characterized. Close inspection of the crystal structure of the HOFs reveals that PTTBN units form a two-dimensional hydrogen-bonded sql network but with varied hydrogen bonding connectivities, packing patterns, and host-guest interactions. The pore system in these HOFs can be systematically modulated by the guest molecules and tuned from discrete cavities to one-dimensional channels with distinct dimensions. Energy decomposition analysis was carried out to investigate the intralayer and interlayer interaction energy to understand the solvent-dependent self-assembly.