Synthesis 2021; 53(17): 2911-2946
DOI: 10.1055/a-1485-5156
special topic
Bond Activation – in Honor of Prof. Shinji Murai

Remote C–H Functionalizations by Ruthenium Catalysis

Korkit Korvorapun
,
,
Torben Rogge
,
Generous support by the DAAD (fellowship to K.K.), the Alexander von Humboldt foundation (fellowship to R.C.S.) and the DFG (SPP1807 and Gottfried-Wilhelm-Leibniz award to L.A.) is gratefully acknowledged.


Dedicated to Prof. Shinji Murai

Abstract

Synthetic transformations of otherwise inert C–H bonds have emerged as a powerful tool for molecular modifications during the last decades, with broad applications towards pharmaceuticals, material sciences, and crop protection. Consistently, a key challenge in C–H activation chemistry is the full control of site-selectivity. In addition to substrate control through steric hindrance or kinetic acidity of C–H bonds, one important approach for the site-selective C–H transformation of arenes is the use of chelation-assistance through directing groups, therefore leading to proximity-induced ortho-C–H metalation. In contrast, more challenging remote C–H activations at the meta- or para-positions continue to be scarce. Within this review, we demonstrate the distinct character of ruthenium catalysis for remote C–H activations until March 2021, highlighting among others late-stage modifications of bio-relevant molecules. Moreover, we discuss important mechanistic insights by experiments and computation, illustrating the key importance of carboxylate-assisted C–H activation with ruthenium(II) complexes.

1 Introduction

2 Stoichiometric Remote C–H Functionalizations

3 meta-C–H Functionalizations

4 para-C–H Functionalizations

5 meta-/ortho-C–H Difunctionalizations

6 Conclusions



Publication History

Received: 24 March 2021

Accepted after revision: 19 April 2021

Accepted Manuscript online:
19 April 2021

Article published online:
20 May 2021

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