A series of new cyclopentadienyl molybdenum compounds bearing substituted phenanthroline ligands [(eta(5)-C5H4CH2C6H4X-4)Mo(CO)(2)(L-N,L-N)][BF4] (X = F, Cl, Br; L-N,L-N=phen, 5-NH2-phen, 4,7-Ph-2-phen) was prepared and characterized using infrared and NMR spectroscopies. Crystal structures of [(eta(5)-C5H4CH2C6H4F-4)Mo(CO)(2)(NCMe)(2)][BF4], [(eta(5)-C5H4CH2C6H4X-4)Mo(CO)(2)(phen)][BF4] (X = F, Cl, Br) and [(eta(5)-C5H4CH2C6H4Cl-4)Mo(CO)(2)(4,7-Ph-2-phen)][BF4](4,7-Ph-2-phen)HBF4 were determined using X-ray diffraction analysis.
Biological studies revealed a strong cytotoxic effect of the chelating ligands. Although the cytostatic effect of the halogen in the side chain of the cyclopentadienyl ring is negligible, it could be used for future post-modification of these types of cytotoxic active molybdenum-based compounds.