Intermolecular interactions boost aggregation induced emission in carbazole Schiff base derivatives

Area of Science:

• Organic Chemistry
• Materials Science
• Photophysics

Background:

• Donor-π-Acceptor (D-π-A) molecules are crucial in optoelectronics.
• Intramolecular charge transfer (ICT) significantly influences optical properties.
• Aggregation-induced emission (AIE) is a desirable phenomenon for advanced materials.

Purpose of the Study:

• To synthesize and characterize novel D-π-A model compounds.
• To investigate their photophysical properties, including ICT and AIE.
• To explore their potential in bio-imaging applications.

Main Methods:

• Synthesis and characterization (NMR, MS, X-ray diffraction).
• UV-Vis absorption and fluorescence spectroscopy.
• Theoretical calculations and scanning electron microscopy (SEM).

Main Results:

• Six D-π-A compounds (1-6) were successfully synthesized and characterized.
• Compounds exhibit significant ICT, leading to distinct optical properties.
• All compounds demonstrated outstanding AIE in water/acetonitrile mixtures.
• Orderly aggregation was identified as the cause of AIE via SEM.
• Cytotoxicity tests confirmed good biocompatibility with living cells.

Conclusions:

• The synthesized D-π-A compounds possess favorable optical properties driven by ICT.
• Their AIE characteristics and biocompatibility suggest potential for fluorescence bio-imaging.
• These findings open avenues for developing new fluorescent probes.