Triarylmethanol Derivatives with Ultralong Organic Room-Temperature Phosphorescence

Area of Science:

• Organic Chemistry
• Materials Science
• Photophysics

Background:

• Triphenylmethane dyes like rhodamines and fluoresceine are established fluorescent labels in bioimaging.
• Ultralong room temperature phosphorescence (RTP) has been observed in triphenylphosphine derivatives.

Purpose of the Study:

• To report a novel methoxy-substituted triarylmethanol, (4-methoxyphenyl)diphenylmethanol (LJW-1), with ultralong RTP.
• To investigate the structure-property relationships influencing RTP in triarylmethanol derivatives.

Main Methods:

• Synthesis of (4-methoxyphenyl)diphenylmethanol (LJW-1).
• Characterization of RTP properties under ambient conditions.
• Analysis of intermolecular interactions (C-H…π, C-H…O, hydrogen bonds, π-π stacking) in the aggregated state.
• Systematic variation of substituents to study their effect on phosphorescence lifetimes.

Main Results:

• LJW-1 exhibits ultralong RTP with an afterglow of approximately 7 seconds.
• Intermolecular interactions contribute to a rigid environment in the aggregated state, crucial for RTP.
• Phosphorescence lifetimes of triarylmethanol derivatives can be tuned from 7 μs to 818 ms by altering substituents.

Conclusions:

• Methoxy-substituted triarylmethanol (LJW-1) is a promising organic material for ultralong RTP applications.
• Substituent effects provide an effective strategy for designing novel organic RTP materials.
• This work provides insights into the phosphorescence mechanisms of triarylmethanol derivatives.