Pd/Cu-catalyzed denitrogenative self-carbonylation of arylhydrazine hydrochlorides to synthesize symmetrical biaryl ketones under CO/O2 pressure has been developed. The arylhydrazine hydrochlorides are used as a green arylating agent which releases nitrogen and water as byproducts. This developed protocol significantly restricts the formation of aryl iodide and azobenzene products even under favorable conditions. Additionally, this protocol provides a series of symmetric carbonylative ketones with a wide variety of functional group tolerance under CO/O2 pressure.
Comprehensive Summary
An efficient Pd/Cu-catalyzed oxidative self-carbonylation of arylhydrazine with CO and molecular oxygen as an oxidant to afford symmetrical biaryl ketones via C—N bond activation has been developed. In this approach, arylhydrazine hydrochlorides are used as a green arylating agent which releases nitrogen and water as byproducts. This developed protocol significantly restricts the formation of aryl iodide and homo-coupled azobenzene products even under favorable conditions. A library of symmetrical biaryl ketones with wide functionalities was synthesized in good yields under mild conditions.