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Title: Chemoselective Transamidation of Thioamides by Transition‐Metal‐Free N−C(S) Transacylation
Abstract

Thioamides represent highly valuable isosteric in the strictest sense “single‐atom substitution” analogues of amides that have found broad applications in chemistry and biology. A long‐standing challenge is the direct transamidation of thioamides, a process which would convert one thioamide bond (R−C(S)−NR1R2) into another (R−C(S)−NR3N4). Herein, we report the first general method for the direct transamidation of thioamides by highly chemoselective N−C(S) transacylation. The method relies on site‐selective N‐tert‐butoxycarbonyl activation of 2° and 1° thioamides, resulting in ground‐state‐destabilization of thioamides, thus enabling to rationally manipulate nucleophilic addition to the thioamide bond. This method showcases a remarkably broad scope including late‐stage functionalization (>100 examples). We further present extensive DFT studies that provide insight into the chemoselectivity and provide guidelines for the development of transamidation methods of the thioamide bond.

 
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Award ID(s):
1650766
NSF-PAR ID:
10372481
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
134
Issue:
16
ISSN:
0044-8249
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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