The addition of the commercially available silver salts AgBF4, AgNTf2 or AgOTf to compounds 1 or 2 causes the release of N2 or C2H4, respectively, and the oxidation of the metal center in compounds 3 (Figure ), evinced by a rapid color change from yellow to green, in line with their corresponding UV-vis spectra (Figures ). An important exception to this reactivity arises from the reaction with Ag[BAr F ], leading to either the dinitrogen complex 1•BAr F or a rather uncommon Ir II -C2H4 adduct (2•BAr F ), from precursor 1 or 2, respectively. At variance with the only other reported example of an Ir II -C2H4 complex, (10b) 2•BAr F maintains its original square planar geometry, as in other Ir II compounds reported herein (Figure ). To complete our Ir II series, we also targeted the corresponding chloride to confront the chemistry of weakly coordinating anions with that of a better donor. Thus, complex 3•Cl could be readily obtained from anion metathesis by the reaction of complexes 3 with excess [ n Bu4N]Cl (Figure ). The reversibility of these one-electron oxidation reactions was corroborated. As foreseen, the reduction of all Ir II complexes could be achieved by reaction with 1 eq. of KC8 without any significant signs of decomposition, leading to precursors either 1 or 2 under N2 or ethylene atmosphere, respectively. All new Ir(II) complexes are silent in 31 P{ 1 H} NMR spectroscopy, but exhibit distinctive broad signals in their 1 H NMR spectra between . Complexes bearing a fluorine or boron-containing counterion feature 19 F{ 1 H} and 11 B{ 1 H} resonances at the usual chemical shifts expected for these anions . By means of unrestricted Density Functional Theory (DFT) calculations at the PBE0-D3/6-311G &LANL2TZ level, we obtained the spin density plot of complexes 1•BAr F , 2•BAr F and 3 (Figures and in the Supporting Information). Contrary to 1•BAr F , for which the unpaired spin is solely centered at the metal dz 2 orbital, for all other Ir II complexes (2•BAr F and 3) it is delocalized between the metal dxz orbital and the π system of the aromatic ring, suggesting a somewhat larger effective oxidation state for the iridium center.