Unravelling nucleophilic aromatic substitution pathways with bimetallic nucleophiles

Abstract

The reaction of a metal complex containing a polar Fe–Mg bond with 2-(pentafluorophenyl)pyridine leads to selective C–F bond activation. A stepwise S_NAr mechanism involving attack of the bimetallic nucleophile on the electron-deficient aromatic ring has been identified by DFT calculations. Despite the long and rich history of metal anions in organic synthesis, this is the first time the S_NAr mechanism has been elucidated in detail for metal-based nucleophiles.