Ligand- and Counterion-Assisted Phenol O-Arylation with TMP-Iodonium(III) Acetates

High reactivity of trimethoxyphenyl (TMP)-iodonium(III) acetate for phenol O-arylation was achieved. It was first determined that the TMP ligand and acetate anion cooperatively enhance the electrophilic reactivity toward phenol oxygen atoms. The proposed method provides access to various diaryl ethers in significantly higher yields than the previously reported techniques. Various functional groups, including aliphatic alcohol, boronic ester, and sterically hindered groups, were tolerated during O-arylation, verifying the applicability of this ligand- and counterion-assisted strategy.

Automated summary

High reactivity of trimethoxyphenyl (TMP)-iodonium(III) acetate was achieved for phenol O-arylation. The cooperation of TMP ligand and acetate anion enhances the electrophilic reactivity towards phenol oxygen atoms. This ligand- and counterion-assisted strategy shows high applicability with tolerance towards various functional groups.