Issue 7, 2017

A well-defined NHC–Ir(iii) catalyst for the silylation of aromatic C–H bonds: substrate survey and mechanistic insights

Abstract

A well-defined NHC–Ir(III) catalyst, [Ir(H)2(IPr)(py)3][BF4] (IPr = 1,3-bis-(2,6-diisopropylphenyl)imidazol-2-ylidene), that provides access to a wide range of aryl- and heteroaryl-silanes by intermolecular dehydrogenative C–H bond silylation has been prepared and fully characterized. The directed and non-directed functionalisation of C–H bonds has been accomplished successfully using an arene as the limiting reagent and a variety of hydrosilanes in excess, including Et3SiH, Ph2MeSiH, PhMe2SiH, Ph3SiH and (EtO)3SiH. Examples that show unexpected selectivity patterns that stem from the presence of aromatic substituents in hydrosilanes are also presented. The selective bisarylation of bis(hydrosilane)s by directed or non-directed silylation of C–H bonds is also reported herein. Theoretical calculations at the DFT level shed light on the intermediate species in the catalytic cycle and the role played by the ligand system on the Ir(III)/Ir(I) mechanism.

Graphical abstract: A well-defined NHC–Ir(iii) catalyst for the silylation of aromatic C–H bonds: substrate survey and mechanistic insights

Supplementary files

Article information

Article type
Edge Article
Submitted
04 Nov. 2016
Accepted
03 Apr. 2017
First published
05 Apr. 2017
This article is Open Access

All publication charges for this article have been paid for by the Royal Society of Chemistry
Creative Commons BY license

Chem. Sci., 2017,8, 4811-4822

A well-defined NHC–Ir(III) catalyst for the silylation of aromatic C–H bonds: substrate survey and mechanistic insights

L. Rubio-Pérez, M. Iglesias, J. Munárriz, V. Polo, V. Passarelli, J. J. Pérez-Torrente and L. A. Oro, Chem. Sci., 2017, 8, 4811 DOI: 10.1039/C6SC04899D

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements