On the Mechanism of the Nickel-Catalyzed Boron Insertion into the C−O Bond of Benzofuran

21 June 2019, Version 1
This content is a preprint and has not undergone peer review at the time of posting.

Abstract

The reaction of benzofurans with diboron reagents and Cs2CO3catalyzed by Ni(0) complexes results in the insertion of boron into the C-O bond. The reaction conditions mimic those reported by Martin and Hosoya for borylating aryl C-F bonds, but neither the role of the base nor the sequence of elementary steps is clear. Herein we report on the mechanism of such transformation on the basis of DFT studies, which suggest that the base activates the diboron reagent and generates a reactive boryl group, that Ni(II) is reduced back to Ni(0) during the boryl insertion into the Ni-O bond, and that the classical reductive elimination step is best viewed as a ring-contracting nucleophilic attack.

Keywords

Nickel
boranes
reaction mechanism
Cross-coupling
benzofuran
dft
NCI
homogeneous catalysis
C-O bond activation

Supplementary materials

Title
Description
Actions
Title
SupportingInformation
Description
Actions

Supplementary weblinks

Comments

Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.