Issue 43, 2010

Alkyneinsertion into cyclometallated pyrazole and imine complexes of iridium, rhodium and ruthenium; relevance to catalytic formation of carbo- and heterocycles

Abstract

The cyclometallated complexes [MCl(C⁁N)(ring)] (HC⁁N = 2-phenylpyrazole, M = Ir, Rh ring = Cp*; M = Ru, ring = p-cymene) readily undergo insertion reactions with RC[triple bond, length as m-dash]CR (R = CO2Me, Ph) to give mono insertion products, the rhodium complex also reacts with PhC[triple bond, length as m-dash]CH regiospecifically to give an analogous product. The products of the reactions of the cyclometallated imine complexes [MCl(C^N)Cp*] (HC⁁N = PhCH[double bond, length as m-dash]NR, R = Ph, CH2CH2OMe, Me; M = Ir, Rh) with PhC[triple bond, length as m-dash]CPh depend on the substituent R; when R = CH2CH2OMe a monoinsertion is observed, however for R = Me the initial insertion product is unstable, undergoing reductive elimination with loss of the organic fragment, and for R = Ph no metal-containing product is isolated. With PhC[triple bond, length as m-dash]CH the cyclometallated imine complexes can give mono or di-insertion products. The implications for catalytic synthesis of carbo- and heterocycles by a tandem C–H activation, alkyne insertion mechanism are discussed.

Graphical abstract: Alkyne insertion into cyclometallated pyrazole and imine complexes of iridium, rhodium and ruthenium; relevance to catalytic formation of carbo- and heterocycles

Supplementary files

Article information

Article type
Paper
Submitted
09 Apr 2010
Accepted
25 May 2010
First published
06 Oct 2010

Dalton Trans., 2010,39, 10447-10457

Alkyne insertion into cyclometallated pyrazole and imine complexes of iridium, rhodium and ruthenium; relevance to catalytic formation of carbo- and heterocycles

Y. Boutadla, D. L. Davies, O. Al-Duaij, J. Fawcett, R. C. Jones and K. Singh, Dalton Trans., 2010, 39, 10447 DOI: 10.1039/C0DT00280A

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