Issue 32, 2010

[(NHC)CuX] complexes: Synthesis, characterization and catalytic activities in reduction reactions and Click Chemistry. On the advantage of using well-defined catalytic systems

Abstract

The preparation of three series of [(NHC)CuX] complexes (NHC = N-heterocyclic carbene, X = Cl, Br, or I) is reported. These syntheses are high yielding and only use readily available starting materials. The prepared complexes were spectroscopically and structurally characterized. Notably, two of them present a bridging NHC ligand between two copper centers in the solid state, an extremely rare coordination mode for these ligands. These complexes were then applied to two distinct organic reactions: the hydrosilylation of ketones and the 1,3-dipolar cycloaddition of azides and alkynes. In both transformations, outstanding catalytic systems were found for preparing the corresponding products in excellent yields and short reaction times. Most remarkably, the screening of well-defined systems in the hydrosilylation reaction allowed for the identification of a pre-catalyst previously overlooked since, originally, catalytic species were in situ generated. Under such conditions, major formation of [(NHC)2Cu]+ species, inactive in this reduction reaction, occurred instead of the expected copper hydride. These results highlight one of the most important advantages of employing well-defined complexes in catalysis: gaining an improved control of the nature of the catalytically relevant species in the reaction media.

Graphical abstract: [(NHC)CuX] complexes: Synthesis, characterization and catalytic activities in reduction reactions and Click Chemistry. On the advantage of using well-defined catalytic systems

Supplementary files

Article information

Article type
Paper
Submitted
28 Mar 2010
Accepted
19 May 2010
First published
13 Jul 2010

Dalton Trans., 2010,39, 7595-7606

[(NHC)CuX] complexes: Synthesis, characterization and catalytic activities in reduction reactions and Click Chemistry. On the advantage of using well-defined catalytic systems

S. Díez-González, E. C. Escudero-Adán, J. Benet-Buchholz, E. D. Stevens, A. M. Z. Slawin and S. P. Nolan, Dalton Trans., 2010, 39, 7595 DOI: 10.1039/C0DT00218F

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements