Selective Cu(ii) sensing by a versatile AIE cyanostilbene-based gel system

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Organic Chemistry

Background:

• Cyanostilbene derivatives are known for their optical properties.
• Gelators are molecules that can form extended networks in solvents.
• Controlling gelation and fluorescence is crucial for developing new materials.

Purpose of the Study:

• To design and synthesize novel cyanostilbene-based derivatives.
• To investigate the impact of structural modifications on gelation and fluorescence.
• To explore the potential of these compounds as soft sensing materials.

Main Methods:

• Synthesis and full characterization of cyanostilbene derivatives.
• Screening of gelating abilities in various solvents (organo- and hydrogels).
• Investigation of metal-ion specific gelation (metallogels) and stimuli-responsive transformations.

Main Results:

• Three cyanostilbene derivatives (1-3) were successfully synthesized and characterized.
• A minor change in pyridine nitrogen position significantly influenced fluorescence and gelation.
• Derivative 1 demonstrated versatile gelation, forming organo-, hydro-, and Cu(II)-specific metallogels.
• A unique room-temperature organogel-to-metallogel transformation was observed for derivative 1 upon addition of Cu(II).

Conclusions:

• Structural nuances in cyanostilbene derivatives critically affect their supramolecular properties.
• Derivative 1 is a promising candidate for developing advanced soft materials.
• The observed gel transformation offers a novel strategy for creating responsive sensing materials.