Bis-cyclometalated Rhodium and Iridium Chloride Complexes Yield Different Products Upon Reaction With 9,10-Diaminophenanthrene

Abstract

The reaction of 9.10-diaminophenanthrene with [{Rh(μ-Cl)(ptpy)2}2] yields – quite unexpected – the new cyclometalated complex salts [Rh(ptpy)2(9,10-diiminophenanthrene)]PF6 (1), whereas with the corresponding dinuclear iridium compound the “usual” [Ir(ptpy)2(9,10-diaminophenanthrene)]PF6 (2) is obtained. The molecular structure of compound 1 was confirmed by single-crystal X-ray diffraction. 1 crystallized in the monoclinic space group P21/n as a dichloromethane solvate. Both compounds display significant cytotoxicity against human cancer cell lines with the IC50 values in the low micromolar range.