Visible-Light-Induced Difunctionalization of Alkenes with Masked Trifluoroacetyl Reagents
Pan Pan1, Shihao Li2,3, Jun Chen2,3
1Anhui Province Key Laboratory of Conservation and Utilization for Dabie Mountain Special Bio-Resources, West Anhui University, Lu'an City 237012, Anhui Province, China.
Organic Letters
|June 26, 2026
Summary
A new visible-light catalytic method enables trifluoroacetylation difunctionalization of alkenes. This strategy efficiently synthesizes valuable trifluoroacetyl building blocks through allylation and amination reactions under mild conditions.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Trifluoroacetyl groups are important in pharmaceuticals and materials.
- Developing efficient methods for introducing trifluoroacetyl groups is crucial.
- Difunctionalization of alkenes offers a pathway to complex molecules.
Purpose of the Study:
- To develop a visible-light catalytic strategy for trifluoroacetylation difunctionalization of electron-deficient alkenes.
- To achieve both trifluoroacetylation allylation and trifluoroacetylation amination of alkenes.
- To provide a convenient and versatile synthetic route to trifluoroacetyl building blocks.
Main Methods:
- Visible-light photoredox catalysis.
- Synergistic photoredox and palladium catalysis for allylation.
- Energy-transfer pathway for amination.
- Mechanistic investigations using radical addition, reduction, and substitution processes.
Main Results:
- Successful development of trifluoroacetylation allylation and amination of electron-deficient alkenes.
- Demonstration of a sequential radical addition, reduction, and substitution mechanism for allylation.
- Achieved difunctionalization via an energy-transfer pathway for amination.
- Protocols exhibit mild reaction conditions, broad substrate scope, and simple operation.
Conclusions:
- A novel visible-light catalytic difunctionalization strategy for electron-deficient alkenes has been established.
- The developed methods provide efficient access to diverse trifluoroacetyl-containing compounds.
- This work offers a convenient approach for synthesizing valuable trifluoroacetyl building blocks.
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