Cu-catalysed transamidation of unactivated aliphatic amides.

Org Biomol Chem

Department of Pharmaceutical Chemistry, Discipline of Pharmaceutical Sciences, College of Health Sciences, University of KwaZulu-Natal (Westville), Durban-4000, South Africa.

Published: August 2022

Direct transamidation is gaining prominence as a ground-breaking technique that generates a wide variety of amides without the requirement of acid-amine coupling or other intermediate steps. However, transamidation of unactivated aliphatic amides, on the other hand, has been a long-standing issue in comparison to transamidation of activated amides. Herein, we report a transamidation approach of an unactivated aliphatic amide using a copper catalyst and chlorotrimethylsilane as an additive. In addition, we used transamidation as a tool for selective N-C(O) cleavage and O-C(O) formation to synthesise 2-substituted benzoxazoles and benzothiazoles. The reactions were carried out without using any solvents and offered wide substitution scope.

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http://dx.doi.org/10.1039/d2ob01152bDOI Listing

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