6-Hydroxyindole-based borondipyrromethene: synthesis and spectroscopic studies
Chunchang Zhao1, Peng Feng, Jian Cao
1Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science & Technology, Shanghai, 200237, PR China. zhaocchang@ecust.edu.cn
Organic & Biomolecular Chemistry
|November 11, 2011
Summary
This study introduces BODIPY-OH, a novel fluorophore whose color can be tuned across a broad spectrum. By altering solvent polarity and base combinations, researchers achieved significant shifts in absorption and emission colors.
Area of Science:
- Organic Chemistry
- Photophysics
- Materials Science
Background:
- Boron-dipyrromethene (BODIPY) dyes are widely used fluorescent probes.
- Tuning the photophysical properties of BODIPY dyes is crucial for advanced applications.
- 6-hydroxyindole scaffolds offer unique electronic properties for dye design.
Purpose of the Study:
- To synthesize and characterize a novel 6-hydroxyindole-based BODIPY derivative (BODIPY-OH).
- To investigate the solvatochromic and photophysical properties of BODIPY-OH and its deprotonated form (BODIPY-O(-)).
- To explore the potential for wide-range color tuning of this fluorophore system.
Main Methods:
- Spectroscopic analysis (absorption and emission) of BODIPY-OH and BODIPY-O(-) in various solvents with organic bases.
- Systematic variation of solvent polarity and base concentration to observe spectral shifts.
- Quantum yield and Stokes shift measurements.
Main Results:
- BODIPY-OH exhibits distinct spectroscopic characteristics.
- The absorption color of the solution can be tuned over 100 nm.
- Emission color is tunable from 571 to 681 nm by converting BODIPY-OH to BODIPY-O(-).
- BODIPY-O(-) shows high quantum yield and large Stokes shifts due to excited-state deprotonation.
Conclusions:
- The 6-hydroxyindole-based BODIPY-OH is a versatile fluorophore with tunable optical properties.
- Solvent polarity and base-induced deprotonation are effective strategies for wide-range color modulation.
- The observed phenomena are attributed to excited-state intramolecular proton transfer (ESIPT) leading to emission from the phenolate form.
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