Selective addition to iridium of aryl C-H bonds ortho to coordinating groups. Not chelation-assisted

Xiawei Zhang, Mira Kanzelberger, Thomas J. Emge, Alan S Goldman

Research output: Contribution to journalArticle

77 Citations (Scopus)

Abstract

Precursors of the pincer-ligated iridium species, (PCP)Ir, react with nitrobenzene or acetophenone at ambient temperature to give O,C-chelated complexes resulting from addition of an aryl C-H bond and coordination of a nitro or acetyl oxygen. The C-H additions appear to be completely regioselective for the position ortho to the functional group; however, structural characterization and low-temperature NMR studies demonstrate that the reaction does not proceed via coordination of the functional group followed by C-H addition. In the case of nitrobenzene, kinetic preference for the para and meta positions is demonstrated at low temperature. Addition occurs more slowly at the ortho position, without assistance by the functional group; the ortho-C-H addition product is then trapped by chelation.

Original languageEnglish
Pages (from-to)13192-13193
Number of pages2
JournalJournal of the American Chemical Society
Volume126
Issue number41
DOIs
Publication statusPublished - Oct 20 2004

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Iridium
Chelation
Functional groups
Nitrobenzene
Temperature
Nuclear magnetic resonance
Oxygen
Kinetics
nitrobenzene

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Selective addition to iridium of aryl C-H bonds ortho to coordinating groups. Not chelation-assisted. / Zhang, Xiawei; Kanzelberger, Mira; Emge, Thomas J.; Goldman, Alan S.

In: Journal of the American Chemical Society, Vol. 126, No. 41, 20.10.2004, p. 13192-13193.

Research output: Contribution to journalArticle

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