Original Research ARTICLE
Reshaping Ullmann Amine Synthesis in Deep Eutectic Solvents: A Mild Approach for Cu-catalysed C–N Coupling Reactions with no Additional Ligands
- 1Department of Pharmacy and Pharmaceutical Sciences, University of Bari Aldo Moro, Italy
The CuI-catalysed Ullmann amine cross-coupling between (hetero)aryl halides (Br, I) and aromatic and aliphatic amines has been accomplished in deep eutectic solvents as environmentally benign and recycling reaction media. Under optimised conditions, the reaction proceeds smoothly under mild conditions (60–100 °C) in air, in the absence of ligands, with a catalyst (CuI) loading of 10 mol% and K2CO3 (aliphatic primary and secondary amines) or t-BuOK (aromatic amines) as the base. A variety of amines have been synthesized in yields up to 98% with a broad substrate scope.
Keywords: Ullmann amination reaction, copper catalysis, Deep eutectic solvents (DESs), amine synthesis, green chemistry
Received: 25 Jun 2019;
Accepted: 10 Oct 2019.
Copyright: © 2019 Quivelli, Vitale, Perna and Capriati. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Prof. Vito Capriati, Department of Pharmacy and Pharmaceutical Sciences, University of Bari Aldo Moro, Bari, Italy, email@example.com