Merging photoredox catalysis with transition metal catalysis: Direct C4-H amination of 8-hydroxyquinoline derivatives

摘要

A practical and efficient protocol for Ag/Ru-cocatalyzed regioselective C-H amination of 8-hydroxyquinoline esters with pyrazoles was developed, This reaction proceeded smoothly via a photoredox-mediated direct C-H/N-H oxidative coupling process. The remarkable features of this reaction include the wide substrate scope, mild reaction conditions and high regioselectivity at the C4 site of the quinolinyl moiety. (C) 2019 Elsevier Ltd. All rights reserved.