Palladium( II )/( III ) complexes of triaza macrocycles: synthesis and single crystal X-ray structures of [Pd III (tacn) 2 ] 3+ and [Pd II (tacn)(tacnH)] 3+ (tacn = 1,4,7-triazacyclononane)

The complex cation [Pd(tacn)2]2+(tacn = 1,4,7-triazacyclononane) shows a one-electron oxidation at E½=+0.07 V vs. Fc/Fc+(ferrocene/ferrocinium) to afford the stable mononuclear PdIII species [Pd(tacn)2]3+, which has a tetragonally-distorted octahedral structure with Pd–N(1)= 2.180(9), Pd–N(4)= 2.118(9), Pd–N(7)= 2.111(9)Å.