Bubbling of CO into a dichloromethane solution of [Ir(COD)(CH 3CN) 2][BF 4] followed by the addition of 2-phenyl-1,8-naphthyridine (LH) at room temperature results in the bis-cyclometalated Ir III complex [Ir(C ^N) 2(CO)(LH)][BF 4] (C ^N = L). The observed cyclometalation contradicts the classical role of CO, which is to hinder oxidative addition by lowering electron density on the metal. DFT calculations reveal that the first cyclometalation involves oxidative addition of the ligand. Subsequently, preferential electrophilic activation of the second ligand followed by elimination of dihydrogen affords the bis-cyclometalated Ir III complex. © 2012 American Chemical Society.