Addition of a Diphosphirenium Salt to Palladium(0) Complexes: The First Examples of Diphosphametallacyclobutenes
Résumé
P-Bis(diisopropylamino)-C-(diisopropylamino) diphosphirenium tetrafluoroborate (1) reacts with palladium tetrakis(triphenylphosphine), affording the tetrafluoroborate salt of2,2-bis(triphenylphosphine)-l,3-diphospha-2-pallada(II)cyclobutene 2 in 70% yield. Exchange of the triphenylphosphine ligands occurs with diphenylmethylphosphine, dimethylphenylphosphine, trimethylphosphine, and l,2-bis(diphenylphosphino)ethane, leading to the corresponding complexes 3-6 in good yields.