Selective ortho-C-H Activation in Arenes without Functional Groups

Chan, Antony PY, Jakoobi, Martin, Wang, Chenxu, O'Neill, Robert T, Aydin, Gulsevim SS, Halcovitch, Nathan, Boulatov, Roman ORCID: 0000-0002-7601-4279 and Sergeev, Alexey G ORCID: 0000-0003-1587-2517 (2022) Selective ortho-C-H Activation in Arenes without Functional Groups. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 144 (26). pp. 11564-11568.

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Abstract

Aromatic C-H activation in alkylarenes is a key step for the synthesis of functionalized organic molecules from simple hydrocarbon precursors. Known examples of such C-H activations often yield mixtures of products resulting from activation of the least hindered C-H bonds. Here we report highly selective <i>ortho</i>-C-H activation in alkylarenes by simple iridium complexes. We demonstrate that the capacity of the alkyl substituent to override the typical preference of metal-mediated C-H activation for the least hindered aromatic C-H bonds results from transient insertion of iridium into the benzylic C-H bond. This enables fast iridium insertion into the <i>ortho</i>-C-H bond, followed by regeneration of the benzylic C-H bond by reductive elimination. Bulkier alkyl substituents increase the <i>ortho</i> selectivity. The described chemistry represents a conceptually new alternative to existing approaches for aromatic C-H bond activation.

Item Type:	Article
Uncontrolled Keywords:	Iridium
Divisions:	Faculty of Science and Engineering > School of Physical Sciences
Depositing User:	Symplectic Admin
Date Deposited:	15 Jun 2022 14:29
Last Modified:	23 Mar 2023 10:46
DOI:	10.1021/jacs.2c04621
Related URLs:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3156535