Macrocyclic C,C´-Diaryl-o-Carborane Derivatives Containing Pseudo-Crown Ether: Emission Enhancement upon Cation Recognition

Abstract

This study reports aggregation-induced emission (AIE) properties of macrocyclic C,C´-diaryl-o-carborane derivatives and modulation of luminescent properties by adding cations through the regulation of excited-state structural relaxation. We synthesized the o-carborane-tethered macrocycles by incorporating oligo(ethylene glycol) chains to V-shaped diaryl-o-carborane units. It was demonstrated that the emission enhancement of macrocycles can be induced upon recognition of the cations in solution, and the degree of hypochromic shift of the emission maximum wavelength significantly depends on the cation size. Moreover, photophysical kinetic analyses indicated that the complexation with cation suppressed non-radiative decay process through restriction of intramolecular motion.