Organocatalyzed ipso hydroxylation of aryl boronic acids in aqueous medium: A metal free approach

Abstract

A highly efficient protocol was developed for the ipso hydroxylation of arylboronic acids using citric acid as an effective organocatalyst. The sustainable methodology offers good to excellent yields with in the rapid reaction time in water as a solvent media and 30% H₂O₂ as an oxidant. The reaction proceeds without the aid of any metal catalyst or base and is simple, safe, and clean. The current protocol enables the access to variety of phenols and is found to be tolerable to the diverse electronic substrates. Even, the devised reaction conditions have been found to be effective in the gram-scale synthesis of an API, Mequinol.

Graphical Abstract

Keywords:

• Arylboronic acids
• ipso hydroxylation
• metal-free
• organocatalyzed

Acknowledgments

The authors are thankful to the Department of Pharmaceutical Sciences and Technology, ICT-Mumbai for providing all the facilities.

Disclosure statement

No potential conflict of interest was reported by the author(s).