Phosphorus(V) Porphyrin-Based Molecular Turnstiles.

Area of Science:

• Supramolecular Chemistry
• Materials Science

Background:

• Molecular machines are crucial for nanoscale applications.
• Controlling molecular motion is key to developing advanced functional materials.

Purpose of the Study:

• To design and synthesize a new cationic molecular turnstile.
• To investigate the dynamic behavior and effector-responsive switching mechanism of the turnstile.

Main Methods:

• Synthesis of a P(V) porphyrin-based molecular turnstile.
• Dynamic behavior investigation using 1D and 2D proton nuclear magnetic resonance (1H NMR) spectroscopy.
• Analysis of effector-induced conformational changes.

Main Results:

• A novel cationic molecular turnstile with pyridyl interaction sites was successfully synthesized.
• The turnstile exists in an open state with free rotor rotation in the absence of effectors.
• Addition of silver (Ag+) or proton (H+) cations reversibly switches the turnstile to closed states, restricting rotor motion.

Conclusions:

• The designed molecular turnstile exhibits controllable dynamic behavior based on external cationic stimuli.
• The reversible switching mechanism opens possibilities for responsive molecular devices.
• This work contributes to the development of switchable supramolecular systems.