A π-Extended Pentadecabenzo[9]Helicene.

Area of Science:

• Organic Chemistry
• Materials Science
• Nanotechnology

Background:

• Helicenes are polycyclic aromatic hydrocarbons known for their unique helical structures.
• Chiral organic molecules with extended pi-conjugated systems are of interest for optoelectronic applications.

Purpose of the Study:

• To synthesize and characterize a novel chiral nanographene with a pentadecabenzo[9]helicene core.
• To investigate the photophysical and chiroptical properties of the synthesized nanographene.

Main Methods:

• Synthesis of the novel chiral nanographene (EP9H).
• Single-crystal X-ray diffraction for structural confirmation.
• Spectroscopic techniques (fluorescence, CD) and cyclic voltammetry for property analysis.

Main Results:

• Successful synthesis and full characterization of EP9H, confirming its helical structure.
• EP9H exhibits near-infrared fluorescence (λem = 684 nm) with a quantum yield of 0.10.
• The molecule displays seven redox states and significant circular dichroism signals.
• EP9H shows an outstanding |glum| value of 4.50×10⁻² and BCPL of 304 M⁻¹ cm⁻¹.

Conclusions:

• The novel chiral nanographene EP9H possesses a unique helical structure and promising optoelectronic properties.
• Its strong chiroptical activity and NIR emission make it a potential candidate for advanced materials.
• Further research into its applications in areas like organic electronics and sensing is warranted.