A Sulfonylimido-Bridged Coordinatively Unsaturated Diiridium Complex: Intramolecular C−H Bond Activation Promoted by a Weak Acid

The sulfonylimido-bridged diiridium complex [Cp*Ir(μ2-NTs)2IrCp*] (1; Cp* = η5-C5(CH3)5, Ts = SO2C6H4CH3-p), readily accessible from the reaction of [Cp*IrCl2]2 with
TsNH2, reacted with P(CH3)3 and HOTf (Tf = SO2CF3) to afford
the adduct [Cp*Ir{P(CH3)3}(μ2-NTs)2IrCp*] and cationic amido−imido complex [Cp*Ir(μ2-NHTs)(μ2-NTs)IrCp*][OTf], respectively. On the other hand, the reaction of 1 with benzoic acid
resulted in intramolecular C−H bond activation, giving the
cyclometalated complex [Cp*Ir{μ2-NHSO2C6H3(CH3)-κ2N,C}2IrCp*].