Transition-Metal-Free O-Arylation of Alcohols and Phenols with S -Arylphenothiaziniums.

Herein, we report the transition-metal-free O-arylation of alcohols and phenols with S -arylphenothiaziniums, which can be easily synthesized from boronic acids. Aryl substituents derived from arylboronic acids were selectively introduced into the hydroxy groups in alcohols and phenols, and a variety of aryl ethers were synthesized. This selectivity is supported by theoretical calculations.