Magnesium-Mediated\nCross-Electrophile Couplings of\nAryl 2‑Pyridyl Esters with Aryl Bromides for Ketone Synthesis\nthrough In Situ-Formed Arylmagnesium Intermediates

Aryl 2-pyridyl esters could efficiently undergo cross-electrophile\ncouplings with aryl bromides with the aid of magnesium as a reducing\nmetal in the absence of a transition-metal catalyst, leading to the\nunsymmetrical diaryl ketones in modest to good yields with wide functionality\ncompatibility. In addition, the reaction could be easily scaled up\nand applied in the late-stage modification of biologically active\nmolecules. Preliminary mechanistic study showed that the coupling\nreaction presumably proceeds through the in situ formation of arylmagnesium\nreagents as key intermediates.