Nickel-Catalyzed Defluorophosphonylation of Aryl Fluorides.

A Ni-catalyzed cross-coupling reaction between aryl fluorides and dialkyl phosphonates [HP(O)(OR) 2 ] (R = secondary alkyl groups) in the presence of potassium tert -butoxide as a base is reported. The reaction converted various aryl fluorides into the corresponding aryl phosphonates even when electron-donating substituents were present on the aromatic ring. The combined experimental and computational studies suggested Ni-K + cooperative action of a Ni(0) complex chelated with a strongly electron-donating ion-bridged dimeric phosphite ligand system [P(OR) 2 O - K + ] 2 that facilitates turnover-limiting C-F bond oxidative addition of aryl fluorides.