This study explores the impact of fluorination levels in azopyridine Lewis bases on their ability to direct the formation of B←N coordination adducts or cocrystals with phenylboronic ester. We hypothesize that the degree of fluorination can be used as a tool to control the outcome of supramolecular bonding competition, thus influencing complex self-assembly.
A series of azopyridines with varying degrees of fluorination were synthesized and reacted with phenylboronic ester. Their structures were analyzed using Hartree-Fock calculations, Hirshfeld surface analyses, and single crystal X-ray diffraction to assess the impact of fluorination on supramolecular interactions.
The study reveals that azopyridines with up to two fluorine atoms form B←N coordination complexes, while perfluorinated azopyridine leads to cocrystal formation through π-stacking interactions. The outcome depends on the electronic properties of the pyridyl nitrogens, influenced by the level of fluorination.
Fluorination in azopyridine Lewis bases serves as an effective strategy to modulate supramolecular bonding competition between boron coordination and π-stacking. This approach enables the selective formation of desired supramolecular structures, highlighting the utility of fluorination in guiding the self-assembly process. The findings have implications for the development of functional materials and 2D devices, offering a novel method for controlling the architecture of supramolecular assemblies
