Title:Organocatalyzed-Aerobic Oxidation of Arylboronic Acids toward the Synthesis
of Phenolic Derivatives
Volume: 20
Issue: 6
Author(s): Laimujam Sidartha Singh, Sourav Banerjee, Indranil Saha and Chandi Charan Malakar*
Affiliation:
- Department of Chemistry, National Institute of Technology Manipur, Imphal, 795004, India
Keywords:
3-nitropyridine, ipso-hydroxylation, organoborons, organocatalysis, potassium tert-butoxide, arylboronic acids.
Abstract: An effective organocatalyzed ipso-hydroxylation of arylboronic acids for the preparation
of phenol derivatives has been demonstrated. The elucidated phenomenon relies on the catalytic
performance of 3-nitropyridine under the influence of sub-stoichiometric quantities of KOtBu
employing aerobic conditions in DMSO solvent. This method excludes the excess usage of oxidizing
agents and bases by providing a user-friendly synthetic tool for the preparation of phenols. It
was acclaimed that the 3-nitropyridine acts as an oxygen transferring agent from in situ generated
hydrogen peroxide to boronic acid derivatives to furnish the desired molecules. The required hydrogen
peroxide was in situ generated from aerial oxygen by the KOtBu-mediated single electron
transfer process. The described process is applicable to a variety of arylboronic acids for the preparation
of phenols in good yields with considerable resistance of functional moiety.