Dual-Stimulus-Driven Dynamically Controllable [3]Rotaxane with Tunable Organic Room-Temperature Phosphorescence.

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Organic Chemistry

Background:

• Dynamic rotaxanes are molecular machines with potential applications in nanoscale devices.
• Controlling molecular motion with external stimuli is crucial for developing advanced functional materials.

Purpose of the Study:

• To develop a dual-stimulus-responsive [3]rotaxane with independent mechanical motions.
• To investigate the controllable photoisomerization and solid-state luminescence properties of the rotaxane.

Main Methods:

• Threading-stoppering strategy for rotaxane synthesis.
• Acid-base titration and distinct light irradiation for stimulus response.
• Spectroscopic techniques to analyze photoisomerization and luminescence.

Main Results:

• A stiff-stilbene-based [3]rotaxane exhibiting reversible shuttling and bidirectional rotation upon acid-base and light stimuli, respectively.
• Independent control over two distinct mechanical motions within the rotaxane.
• Adjustable photoisomerization kinetics and controllable solid-state organic room-temperature phosphorescence (RTP).

Conclusions:

• The developed rotaxane functions as a dual-stimuli-responsive molecular machine with two independent modes of motion.
• The rotaxane's tunable RTP and photoisomerization properties enable applications in information encryption and anticounterfeiting.
• This work provides a blueprint for designing advanced molecular machines with precise control over motion and luminescence.