meta -C-H functionalization of phenylethyl and benzylic alcohol derivatives via Pd/NBE relay catalysis.

The transition metal-catalyzed meta -C-H functionalization of alcohols and their hydroxylamine derivatives remains underdeveloped. Herein, we report an efficient meta -C-H arylation of both phenylethyl and benzylic alcohols and their hydroxylamine derivatives using a readily removable oxime ether directing group. Using electronically activated 2-carbomethoxynorbornene as the transient mediator and 3-trifluoromethyl-2-pyridone as the enabling ligand, this reaction features a broad substrate scope and good functional group tolerance. More importantly, with this oxime-directed meta -C-H functionalization, this method provides a dual approach for efficient access to both meta -substituted alcohols and hydroxylamines using two sets of simple deprotection conditions. This protocol leads to the efficient synthesis of bioactive compounds possessing promising reactivities for the treatment of pulmonary fibrosis.
Competing Interests: There are no conflicts to declare.
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