Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.



Identification of key functionalization species in the Cp*Ir(iii)-catalyzed-ortho halogenation of benzamides

Author affiliations

Abstract

Cp*Ir(III) complexes have been shown to be effective for the halogenation of N,N-diisopropylbenzamides with N-halosuccinimide as a suitable halogen source. The optimized conditions for the iodination reaction consist of 0.5 mol% [Cp*IrCl2]2 in 1,2-dichloroethane at 60 °C for 1 h to form a variety of iodinated benzamides in high yields. Increasing the catalyst loading to 6 mol% and the time to 4 h enabled the bromination reaction of the same substrates. Reactivity was not observed for the chlorination of these substrates. A variety of functional groups on the para-position of the benzamide were well tolerated. Kinetic studies showed the reaction dependence is first order in iridium, positive order in benzamide, and zero order in N-iodosuccinimide. A KIE of 2.5 was obtained from an independent H/D kinetic isotope effect study. Computational studies (DFT-BP3PW91) indicate that a CMD mechanism is more likely than an oxidative addition pathway for the C–H bond activation step. The calculated functionalization step involves an Ir(V) species that is the result of oxidative addition of acetate hypoiodite that is generated in situ from N-iodosuccinimide and acetic acid.

Graphical abstract: Identification of key functionalization species in the Cp*Ir(iii)-catalyzed-ortho halogenation of benzamides

Back to tab navigation

Supplementary files

Article information


Submitted
15 Feb 2020
Accepted
13 Apr 2020
First published
13 Apr 2020

Dalton Trans., 2020, Advance Article
Article type
Paper

Identification of key functionalization species in the Cp*Ir(III)-catalyzed-ortho halogenation of benzamides

A. J. Guzmán Santiago, C. A. Brown, R. D. Sommer and E. A. Ison, Dalton Trans., 2020, Advance Article , DOI: 10.1039/D0DT00565G

Social activity

Search articles by author

Spotlight

Advertisements