Columnar self-assembly of novel benzylidenehydrazones and their difluoroboron complexes: Structure-property correlations

Abstract

Organoboron complexes are considered to be an important class of optically dynamic materials and because of their imperative properties, they have been unceasingly studied in a wide range of scientific areas. In this context, a new family of D-A-D? architectured boron difluoride complexes FB1-4 derived from arylhydrazones HZ1-4 has been synthesized and characterized. The work also deliberates detailed studies on their thermal, self-assembling and optoelectronic properties with respect to structural modifications. The systematic studies reveal that the new arylhydrazone ligands and their BF<inf>2</inf> complexes exhibit a prospective columnar mesomorphism with different 2D lattice geometries at room temperature, owing to their critical structural features. Interestingly, an unusual morphological cross-over from a columnar hexagonal to rectangular mesophase has been confirmed in one of the investigated pseudo-discoidal boron complexes, FB4. The optoelectronic studies showcased their ICT dominating dye properties. Finally, the experimental results have been consciously correlated with quantum chemical simulations. © 2019 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.