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. 2023 Aug 18;88(16):11847-11854.
doi: 10.1021/acs.joc.3c01127. Epub 2023 Jul 28.

Directing-Group-Free Arene C(sp2)-H Amination Using Bulky Aminium Radicals and DFT Analysis of Regioselectivity

Nicole Erin Behnke  1 , Young-Do Kwon  1 , Michael T Davenport  2 , Daniel H Ess  2 , László Kürti  1
Affiliations

Directing-Group-Free Arene C(sp2)-H Amination Using Bulky Aminium Radicals and DFT Analysis of Regioselectivity

Nicole Erin Behnke et al. J Org Chem. .

Abstract

A hydroxylamine-derived electrophilic aminating reagent produces a transient and bulky aminium radical intermediate upon in situ activation by either TMSOTf or TFA and a subsequent electron transfer from an iron(II) catalyst. Density functional theory calculations were used to examine the regioselectivity of arene C-H amination reactions on diversely substituted arenes. The calculations suggest a simple charge-controlled regioselectivity model that enables prediction of the major C(sp2)-H amination product.

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Conflict of interest statement

Notes

The authors declare no competing financial interest.

Figures

Figure 1.
Figure 1.
Transition Metal-Catalyzed Aromatic C–H amination.
Figure 2.
Figure 2.
M06–2X energy landscape for reaction between [(TMS)2NH]•+ radical cation and 2-methoxybenzonitrile. Black lines represent energies for the major regioisomer. Blue lines represent energies for the minor regioisomer. Enthalpies/Gibbs energies reported in kcal/mol.
Figure 3.
Figure 3.
Charge-controlled regioselectivity model and the prediction of major arene C–H amination product using the model.
See this image and copyright information in PMC

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