Dynamic Covalent Switches and Communicating Networks for Tunable Multicolor Luminescent Systems and Vapor-Responsive Materials

Molecular switches are an intensive
area of research, and in particular,
the control of multistate switching is challenging. Herein we introduce
a general and versatile strategy of dynamic covalent switches and
communicating networks, wherein distinct states of reversible covalent
systems can induce addressable fluorescence switching. The regulation
of intramolecular ring/chain equilibrium, intermolecular dynamic covalent
reactions (DCRs) with amines, and both permitted the activation of
optical switches. The variation in electron-withdrawing competition
between the fluorophore and 2-formylbenzenesulfonyl unit afforded
diverse signaling patterns. The combination of switches in
situ further enabled the creation of communicating networks
for multistate color switching, including white emission, through
the delicate control of DCRs in complex mixtures. Finally, reversible
and recyclable multiresponsive luminescent materials were achieved
with molecular networks on the solid support, allowing visualization
of different types of vapors and quantification of primary amine vapors
with high sensitivity and wide detection range. The results reported
herein should be appealing for future studies of dynamic assemblies,
molecular sensing, intelligent materials, and biological labeling.