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[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
Pyridine-Boryl Radical-Enabled Reductive Radical Brook Rearrangement.
Wenbo Bai1, Yongwei Luo1, Liuxin Luo1
1Key Laboratory of Silicon Chemical New Materials, School of Chemistry and Chemical Engineering, Shihezi University, Shihezi 832003, China.
Organic Letters
|June 11, 2026
Summary
A new reductive radical Brook rearrangement uses N-alkoxyphthalimides to create functionalized silyl ethers. This metal-free method involves a radical cascade and is simple to perform under mild conditions.
Area of Science:
- Organic Chemistry
- Radical Chemistry
- Synthetic Methodology
Background:
- Radical rearrangements are crucial for C-C bond formation.
- Developing new radical-based synthetic methods is an active area of research.
- Brook rearrangement typically requires specific conditions and reagents.
Purpose of the Study:
- To develop a novel reductive radical Brook rearrangement.
- To utilize N-alkoxyphthalimides as accessible radical precursors.
- To synthesize functionalized silyl ethers via a radical cascade.
Main Methods:
- Employing a pyridine-boryl radical system for catalysis.
- Initiating the reaction via single-electron reduction of N-alkoxyphthalimides.
- Facilitating a radical cascade involving N-O bond cleavage and 1,2-silyl migration.
- Intercepting generated alpha-silyloxy carbon radicals with electron-deficient alkenes.
Main Results:
- Successful execution of a reductive radical Brook rearrangement.
- Generation of nucleophilic alpha-silyloxy carbon radicals.
- Efficient synthesis of functionalized silyl ethers.
- Demonstration of operational simplicity and mild reaction conditions.
Conclusions:
- The developed method offers a straightforward route to functionalized silyl ethers.
- The protocol is metal-free, oxidant-free, and operates under mild thermal conditions.
- N-alkoxyphthalimides serve as effective precursors in this radical system.
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