Perspective on Ruthenium–Copper-Mediated Dehydrogenative C–N Bond Formation

Abstract

In 2014, the direct dehydrogenative construction of ubiquitous C–N bonds remains a significant challenge, but recent communications in this field show that this is about to change. Here we highlight a novel ruthenium-catalyzed method for C–H activation and dehydrogenative C–N cross-coupling of unprotected diarylamines in an intermolecular fashion, with carbazoles. The resulting compounds, lauternamines, show unexpected and unprecedented H-bonded stabilized axial chirality. These promise new exciting developments in C–N dehydrogenative couplings.

1 Introduction

2 The intramolecular H-bond is not as innocent as it seems

3 Counter-intuitively, C–H activation is the easy step

4 Using tetrachloroethylene in metal catalysis: a breakthrough?

5 How we understand the mechanism today

Key words

C–H activation - oxidative amination - dehydrogenative cross-coupling - axial chirality - lauternamines

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