Phosphinylation of Non-activated Aryl Fluorides through Nucleophilic Aromatic Substitution at the Boundary of Concerted and Stepwise Mechanisms.

Non-activated aryl fluorides reacted with potassium diorganophosphinites through a nucleophilic aromatic substitution (SN Ar) reaction. Remarkably, both electron-neutral and electron-rich aryl fluorides participated in the reaction with substantially stabilized anionic P nucleophiles to form the corresponding tertiary phosphine oxides. Quantum chemical calculations suggested a nucleophile-dependent mechanism that involves both concerted and stepwise SN Ar reaction pathways.