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DOI: 10.1055/a-2176-1840
Direct Electrochemical C(sp3)–H Amidation Enabled by Hexafluoroisopropanol (HFIP)
We are grateful to the National Natural Science Foundation of China (21702113, 92061110, and 22001241), the Anhui University (S020318006/069 and S020118002/113), the Anhui Provincial Natural Science Foundation (2108085Y05 and 2308085Y14), and the Hefei National Laboratory for Physical Sciences at the Microscale (KF2020102) for their financial support.
![](https://www.thieme-connect.de/media/10.1055-s-00032269/202304/lookinside/thumbnails/so-2023-t0054-l_10-1055_a-2176-1840-1.jpg)
Abstract
A direct electrochemical amidation of xanthene was readily achieved under direct anodic oxidation. The reactivity of benzamides was significantly enhanced by the virtue of the solvent effect of hexafluoroisopropanol (HFIP). An obvious hydrogen bonding between HFIP and benzamide was detected, and the proton-coupled electron-transfer (PCET) effect was proposed for the enhancement effect of HFIP. In this transformation, a broad range of primary and secondary amides were readily used as amidating reagents, including l-proline-, naproxen-, and probencid-derived amides. We proposed a plausible reaction mechanism for this direct amidation based on the experimental observations.
Supporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/a-2176-1840.
- Supporting Information
Publication History
Received: 01 August 2023
Accepted after revision: 14 September 2023
Accepted Manuscript online:
14 September 2023
Article published online:
18 October 2023
© 2023. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by/4.0/)
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For the synthesis of amides, see:
For the approaches involving C(sp3)–H activation, see:
For the approaches involving nitrene insertion, see:
For reviews of synthetic electrochemistry, see:
For bioactive xanthene, see: