Metallkomplexe mit biologisch wichtigen Liganden, XL [1]. Iridium(III)-Komplexe mit 9-Methylguanin / Metal Complexes with Biologically Important Ligands, XL [1]. Iridium(III) Complexes with 9-Methylguanine

The dinitrogen-tetrafluoroborato complex (Ph3P)2(Cl)(N2)(H)IrFBF3 reacts with 9-m ethylguanine in CH2Cl2 to give [(Ph3P)2(Cl)(H)Ir(9-methylguanine)]+BF4 - (2). From a solution of 2 in methanol the complex (Ph3P)2(Cl)2(H)Ir(9-methylguanine) (3) is obtained. The reaction of [(Ph3P)2(Cl)(N2)(H)IrOSO2C4F9] with 9-methylguanine affords the com plexes [(Ph3P)2(Cl)(N2)(H)Ir(9-methylguanine)]+C4F9SO3 - (5) and [(Ph3P)2(Cl)(H2O)(H)Ir(9-methylguanine)]+ C4F9SO3 - (6). The coordination of the guanine derivative to the iridium atom in 2, 5, 6 is discussed on the basis of the infrared spectra. The crystal structure of 3 was determined. 9-Methylguanine is coordinated via N (7). Intermolecular hydrogen bonding between the chloro-ligand and HN (1) of guanine leads to linear chains in the crystal.