Electron Donor-Acceptor (EDA) Complex Formation via Spatial Control of Donor-Acceptor Interactions

Area of Science:

• Molecular Chemistry
• Photochemistry
• Materials Science

Background:

• Electron donor-acceptor (EDA) complexes are crucial in photoactive materials like fluorescence probes and photoredox catalysts.
• Developing efficient intramolecular EDA complexes requires refined design guidelines.
• Current understanding of linker effects on intramolecular EDA complex formation is limited.

Purpose of the Study:

• To systematically investigate linker structures for optimizing intramolecular EDA complexes.
• To identify optimal linker designs for enhancing EDA complex formation efficiency.
• To establish a versatile core structure for synthesizing single-molecule EDA complexes.

Main Methods:

• Systematic investigation of linker structures between indole (electron donor) and dinitrobenzene (electron acceptor) moieties.
• Synthesis and characterization of single-molecule EDA complexes with varying linkers.
• Evaluation of EDA complex efficiency in solution and solid states.

Main Results:

• Identification of trans-1,2-cyclohexanediamine as an optimal linker.
• The optimal linker features a fixed conformation stabilized by an intramolecular hydrogen bond.
• Highly efficient EDA complex formation was achieved in both solution and solid states.

Conclusions:

• The trans-1,2-cyclohexanediamine linker enables highly efficient intramolecular EDA complex formation.
• A versatile core structure is proposed for the synthesis of diverse single-molecule EDA complexes.
• This work provides critical design insights for advanced photoactive molecules.