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Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
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Thianthrenium Salts in Photochemistry.
1Max-Planck-Institut für Kohlenforschung, D45470 Mülheim an der Ruhr, Germany.
Accounts of Chemical Research
|March 4, 2026
Summary
Thianthrenium (TT) salts are versatile reagents for photochemistry and catalysis. They enable efficient radical generation through single-electron transfer or energy transfer, offering distinct advantages over traditional methods.
Area of Science:
- Organic Chemistry
- Photochemistry
- Catalysis
Background:
- Thianthrenium (TT) salts are emerging reagents with broad applications in catalysis and photochemistry.
- They offer advantages over traditional aryl (pseudo)halides, especially in single-electron transfer processes under visible light.
- Their unique redox properties facilitate radical generation and avoid back-electron transfer issues.
Purpose of the Study:
- To explore the evolution and diverse applications of thianthrenium chemistry in photochemistry.
- To highlight advances in photocatalysis, including single-electron transfer (SET) and energy transfer (EnT) mechanisms.
- To discuss direct photolysis and biocompatible applications of TT analogues.
Main Methods:
- Investigated thianthrenium salts in various catalytic systems: transition-metal catalysis, photoredox catalysis, and energy transfer catalysis.
- Analyzed mechanistic pathways including SET, triplet energy transfer (EnT), and direct photolysis.
- Developed selenonium-based TT analogues for site-selective biomacromolecule modification.
Main Results:
- Thianthrenium salts exhibit favorable redox potentials for photoredox catalysis and low triplet energies for efficient EnT.
- Direct photolysis of TT and selenium salts enables radical generation with visible light.
- Selenonium-based TT analogues allow for photochemical late-stage modification of biomolecules under physiological conditions.
Conclusions:
- Thianthrenium chemistry provides practical and mechanistically distinct solutions for modern radical chemistry.
- These reagents offer versatile activation modes, expanding the scope of photochemical transformations.
- The development of TT analogues, including selenonium-based systems, opens new avenues in catalysis and bioconjugation.
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