Construction of Microbelts through the Coassembly of a Disclike Molecule and Primary Alkyl Ammoniums: A Noncovalent Strategy to Mimic Covalently Bonded π-Core Alkyl Chain Structure

In this letter, we report the fabrication of microbelts through the coassembly of hexa-2-pyridyl-hexaazatriphenylen (HPHAT), a disklike pi-conjugated molecule, with primary alkyl ammonium triflate. The strategy is first to construct hydrogen-bonded complexes between HPHAT and primary alkyl ammoniums to mimic covalently bonded pi-core alkyl chain structures, and then the complexes self-assemble into microbelts driven by pi-pi stacking in the pi core and van der Waals interactions between the peripheral alkyl chains. The morphology of as-prepared microbelts has been characterized with scanning electron microscopy (SEM), optical microscopy, polarizing microscopy, and transmission electron microscopy (TEM). Spectroscopic and crystallographic investigations were also carried out to reveal the formation mechanism of the microbelts, through which a sequential self-assembly process has been proposed.