Ipso Nitration of Aryl Boronic Acids Using Fuming Nitric Acid

The ipso nitration of aryl boronic acid derivatives has been developed using fuming nitric acid as the nitrating agent. This facile procedure provides efficient and chemoselective access to a variety of aromatic nitro compounds. While several activating agents and nitro sources have been reported in the literature for this synthetically useful transformation, this report demonstrates that these processes likely generate a common active reagent, anhydrous HNO3. Kinetic and mechanistic studies have revealed that the reaction order in HNO3 is >2 and indicate that the (NO2)-N-center dot radical is the active species.

Automated summary

The ipso nitration of aryl boronic acid derivatives using fuming nitric acid has been developed, providing an efficient and chemoselective approach to various aromatic nitro compounds. This study reveals that the activation agents and nitro sources reported in the literature likely generate a common active reagent, anhydrous HNO3, with kinetic and mechanistic studies indicating that the (NO2)-N-center dot radical is the active species.