Chemo- and Site-Selective Electro-Oxidative Alkane Fluorination by C(sp3 )-H Cleavage
Maximilian Stangier1, Alexej Scheremetjew1, Lutz Ackermann1
1Institut für Organische und Biomolekulare Chemie Wöhler Research Institute for Sustainable Chemistry (WISCh), Georg-August-Universität Göttingen, Tammannstrasse 2, 37077, Göttingen, Germany.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|July 18, 2022
Summary
A novel metal-free electrochemical method enables selective fluorination of C(sp3)-H bonds using nucleophilic fluoride. This strategy offers high functional group tolerance for late-stage fluorination and subsequent synthetic transformations.
Area of Science:
- Organic Chemistry
- Electrochemistry
- Fluorination Chemistry
Background:
- Selective functionalization of C(sp3)-H bonds remains a significant challenge in organic synthesis.
- Traditional fluorination methods often require harsh reagents or lack selectivity.
- Developing milder and more efficient fluorination techniques is crucial for accessing complex molecules.
Purpose of the Study:
- To develop a chemo- and site-selective electrochemical fluorination method for C(sp3)-H bonds.
- To establish a metal-free strategy that avoids electrophilic fluorine sources and stoichiometric oxidants.
- To demonstrate the utility of this method for late-stage fluorination of biorelevant compounds.
Main Methods:
- Electrochemical fluorination utilizing a nucleophilic fluoride source.
- Metal-free reaction conditions.
- One-pot sequential fluorination and arylation reactions.
Main Results:
- Successful chemo- and site-selective fluorination of C(sp3)-H bonds was achieved.
- The method demonstrated high functional group tolerance, enabling late-stage fluorination.
- Subsequent one-pot arylation of the generated benzylic fluorides showcased synthetic utility.
Conclusions:
- A new, efficient, and selective electrochemical method for C(sp3)-H fluorination has been developed.
- This metal-free approach broadens the scope of late-stage fluorination strategies.
- The methodology provides a valuable tool for the synthesis of fluorinated organic molecules.
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