A terphenyl phosphine as a highly efficient ligand for palladium-catalysed amination of aryl halides with 1° anilines

A terphenyl phosphine ligand (2,6-bis(2,4,6-triisopropylphenyl)phenyl-dicyclohexylphosphine, TXPhos) and its supported palladium complex [(TXPhos)(allyl)PdCl] have been developed and the catalyst system is highly efficient in amination of aryl halides with 1° anilines, especially effective for densely functionalized substrates including both partners possessing ortho-ester, acetyl, nitrile and nitro groups. With the TXPhos-supported catalyst system, many partner combinations have been unprecedentedly realized and the base scope has been even extended to KOAc, which is even the best choice in the amination of 2-nitrochlorobenzene.