Homoleptic palladium complexes with phosphine-amide or iminophosphine ligands

The reaction between Pd(dba)2 and phosphino-amide ligands yielded the unexpected Pd(II) homoleptic complexes [Pd(o-Ph2PC6H4CO-NR)2] [R = iPr (1), Ph (2), 4-MeC6H4 (3), 4-FC6H4 (4)], in which an κ2-P,N coordination mode for diphenylphosphine–benzamidate ligands is observed. In order to induce amide protonation in the ligands and subsequent κ2-P,O coordination, compounds (1-4) were treated with HClO4(aq) to give cationic complexes...