Chiral Diazatriptycene Exhibiting Acid-Induced Ternary Circularly Polarized Luminescence Switching and Crystal Morphology Changes

Angew Chem Int Ed Engl. 2025 Jul 28;64(31):e202506733. doi: 10.1002/anie.202506733. Epub 2025 May 20.

Abstract

Doubly N-doped triptycene 2,6-diazatriptycene 1 was synthesized as the first example of triptycene-bearing intrinsic chirality in its core. The resolved enantiomers exhibited an acid-induced ternary circularly polarized luminescence (CPL) switching behavior, enabling on/off and +/- control, with a dissymmetry factor (glum) of approximately 10-3. Density functional theory calculations indicated that these ternary CPL changes were derived from modulation of through-space conjugation within the triptycene skeleton. In addition, single-crystal X-ray analysis of 1 and the salt 1•(TfOH)n revealed the presence of herringbone arrangements, trimer clusters, chiral porous tubes, and 2D charge-segregated array structures. These results demonstrate that precise change of the molecular assembly can be achieved using N-doped chiral triptycene facilitated by ionic hydrogen bonding and donor-acceptor π-π stacking.

Keywords: Chiral materials; Chiroptical switch; Porous crystal; Supramolecular chemistry; Triptycene.