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Relative Strength of Common Directing Groups in Palladium-Catalyzed Aromatic C-H Activation.

ABSTRACT: Efficient functionalization of C-H bonds can be achieved using transition metal catalysts, such as Pd(OAc)₂. To better control the regioselectivity in these reactions, some functional groups on the substrate may be used as directing groups, guiding the reactivity to an ortho position. Herein, we describe a methodology to score the relative strength of such directing groups in palladium-catalyzed aromatic C-H activation. The results have been collected into a scale that serves to predict the regioselectivity on molecules with multiple competing directing groups. We demonstrate that this scale yields accurate predictions on over a hundred examples, taken from the literature. In addition to the regioselectivity prediction on complex molecules, the knowledge of the relative strengths of directing groups can also be used to work with new combinations of functionalities, exploring uncharted chemical space.

SUBMITTER: Tomberg A

PROVIDER: S-EPMC6818342 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Relative Strength of Common Directing Groups in Palladium-Catalyzed Aromatic C-H Activation.

Tomberg Anna A Muratore Michael Éric MÉ Johansson Magnus Jan MJ Terstiege Ina I Sköld Christian C Norrby Per-Ola PO

iScience 20190927

Efficient functionalization of C-H bonds can be achieved using transition metal catalysts, such as Pd(OAc)<sub>2</sub>. To better control the regioselectivity in these reactions, some functional groups on the substrate may be used as directing groups, guiding the reactivity to an ortho position. Herein, we describe a methodology to score the relative strength of such directing groups in palladium-catalyzed aromatic C-H activation. The results have been collected into a scale that serves to predi ...[more]

PMID: 31614320

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