Substituent effects in solid-state assembly of activated benzotriazoles

Aromatic donor-acceptor stacking involving electron-rich -donors and electron-deficient -acceptors has been utilized in a broad spectrum of diverse applications to great effect. We report the discovery of unprecedented donor-acceptor stacking from a non-mixed activated benzotriazole scaffold to give cofacial -stacking in 2D sheets. We further report the effects of altering the substituents of the bicyclic aromatic system. It was found that any alteration made to the substituents disrupted the cofacial stacking, however, both aromatic donor-acceptor stacking and 2D sheet formation was observed in the solid-state assembly of the analogues. Furthermore, interactions that satisfied both electrostatic and direct-substituent -stacking models were observed.