The reaction of [Ir(2)(mu-Cl)(2)(coe)(4)] with 1,1-bisdiphenylphosphinomethane under CO(2) atmosphere affords the complex [IrCl(dppm)(H){(Ph(2)P)(2)C-COOH}](2) by initial CH activation followed by formal insertion of CO(2) into the C-H bond of the formed diphosphanylmethanide ligand.