Transition Metal-Free O-Arylation of N-Alkoxybenzamides Enabled by Aryl(trimethoxyphenyl)iodonium Salts

Herein, we develop a metal catalyst-free protocol for O-arylation of benzamide hydroxamate esters. The chemoselective O- versus N-arylation of the amides was tuned by varying the electronic and/or steric properties of the diaryliodonium salt and/or the substrate. The O-arylation reaction would preferentially occur for sterically and electronically diverse substrates. This study, which reveals the possibility of substituent- and reagent-controlled chemoselectivity, with diaryliodonium salts might attract interest in the area of hypervalent iodine chemistry.

Automated summary

We developed a metal catalyst-free protocol for O-arylation of benzamide hydroxamate esters. By varying the electronic and/or steric properties of the diaryliodonium salt and/or the substrate, the chemoselective O- versus N-arylation of the amides was controlled. The O-arylation reaction showed preference for sterically and electronically diverse substrates. This study demonstrates the possibility of substituent- and reagent-controlled chemoselectivity with diaryliodonium salts and may draw interest in the field of hypervalent iodine chemistry.