Copper catalyzed aryl amidation between N^α-Fmoc-protected amino-acid azides and aryl boronic acids

Abstract

A simple and efficient method for the synthesis of aryl amides via oxidative copper-catalyzed coupling of commercially available aryl boronic acids and bench stable N^α-protected amino-acid azides is reported. The potential utility of this protocol is demonstrated through a survey of diversely substituted aryl boronic acids and several side-chain functionalized amino-acid azides, leading to the preparation of the desired amidated products in good to excellent yields. This amide synthesis is suitable for the preparation of amides (such as peptide aryl amides and sterically hindered amino acids) that are not or hardly accessible via classical approaches.

Graphical Abstract

Keywords:

• Amide bond
• aryl boronic acid
• copper(I) bromide dimethyl sulfide
• N^α-Fmoc-amino-acid azides

Acknowledgements

We are grateful to acknowledge the financial support from SERB, New Delhi, Government of India. One of the authors, Roopesh Kumar, is thankful to DST Nano Mission for the fellowship.