Metal-Free Boron-Mediated <i>ortho</i>-C–H Hydroxylation of <i>N</i>-Benzyl-3,4,5-tribromopyrazoles
Gaorong Wu, Zhaoziyuan Yang, Xiaobo Xu, Liqiang Hao, Lu Chen, Yangyang Wang, Yafei Ji
Abstract
A novel route has been reported for C–H hydroxylation of benzyl compounds directed by a 3,4,5-tribromopyrazole auxiliary via boronation/oxidation using BBr3 and NaBO3·4H2O. The strategy exhibits outstanding site selectivity and affords the corresponding phenols in moderate to excellent yields under metal-free conditions. Besides, this protocol can be achieved in one pot, which is highly promising as a practical method for use in a multistep organic synthetic process.
Topics & Concepts
ChemistryHydroxylationBoronMetalMedicinal chemistryStereochemistryOrganic chemistryEnzymeChemical Reactions and IsotopesCatalytic C–H Functionalization MethodsFluorine in Organic Chemistry