Solvent-Switched Schiff-Base Macrocycles: Self-Sorting and Self-Assembly-Dependent Unconventional Organic Particles

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Organic Synthesis

Background:

• Organic reactions are vital for synthesizing new materials, but direct fabrication of organic particles remains challenging.
• Few studies have explored using organic reactions for the direct, controlled synthesis of micro/nanoparticles.

Purpose of the Study:

• To report a novel, one-step method for fabricating tunable organic micro/nanoparticles.
• To investigate the role of water as a co-solvent in Schiff-base reactions for particle formation.
• To elucidate the self-sorting mechanisms governing particle assembly.

Main Methods:

• Schiff-base reaction utilizing macrocyclic precursors in the presence of water as a co-solvent.
• Room temperature synthesis allowing for controlled precipitation of organic particles.
• X-ray structure analysis and characterization techniques to determine particle morphology and assembly.

Main Results:

• A facile, one-step precipitation of tunable organic micro/nanoparticles (microspheres, core-shell spheres, vesicles) was achieved with high yield.
• Water efficiently switched [2+2] macrocycles to [1+1] macrocycles, driving particle formation.
• Social and narcissistic self-sorting of macrocyclic frameworks via noncovalent interactions were identified as key assembly mechanisms.
• In situ monitoring of intermediate particle formation was possible due to mild reaction conditions.

Conclusions:

• This work presents a significant advancement in the fabrication of tunable organic particles through a mild and efficient Schiff-base reaction.
• The findings highlight the crucial role of self-sorting phenomena in the self-assembly of complex organic nanostructures.
• The developed method offers a versatile platform for creating diverse organic particle morphologies for potential applications.