Stimuli-Responsive B/N Lewis Pairs Based on the Modulation of B–N Bond Strength

A series of robust organoboranes with electronically tunable functionality of B/N Lewis pairs has been achieved. These compounds feature a B/N-containing core in which the interactions between the B and N atoms are modulated as a result of the structural flexibility of the nonconjugated backbone. Examination of the substituent effects of the Lewis base moiety reveals that bulky or aryl substituents favor the dynamic switching of the B-N bond in response to external stimuli, such as heat or mechanical pressure, leading to emission color modulation. This work provides a new, straightforward proof of concept toward new switchable materials design based on tunable electronic interactions.