Triarylphosphines as Aryl Donors for Pd(II)-Catalyzed Aromatic Coupling of Oxabenzonorbornadienes

A new approach was developed for Pd­(II)-catalyzed aromatic coupling of oxabenzo­norbornadienes with triaryl­phosphines as both ligands and aryl donors. Diverse functional groups including halo- (F–, Cl–, and Br−), CF3-, and furyl groups are well tolerated. For unsymmetrical triarylphosphines, the migration ability of aryls is consistent with the electronic property of substituents and maintains the order EDG–Ar > H–Ar > EWD–Ar (EDG means electron-donating group, EWG means electron-withdrawing group). A preliminary mechanistic study was also disclosed.