The new complexes Ti(η5-C5H5)Cl(OC6H4NH2-3)2, Ti(η5-C5H5)Cl(O2CPh)2, Ti(η5-C5H5)2(O2C(S)C6H4-1,2), Ti(η5-C5H5)2Cl(SC6H4OH-4), Ti(η5-C5H5)2(OC6H4NH2-3)2 and Ti(η5-C5H5)2Cl(OC6H4Z) (Z = NO2-2, NO2-3, NO2-4, NH2-3) have been synthesized. The free amine group in Ti(η5-C5H5)2Cl(OC6H4NH2-3) reacts with RCl [R = MeCO, PhCO, (OCCO)1/2, Br(CH2)3CO] in the presence of base to give Ti(η5-C5H5)2Cl(R) but, in the absence of base, PhCOCl reacts to give PhCONHC6H4OH-3 and Ti(η5-C5H5)2Cl2. The X-ray crystal structure of Ti(η5-C5H5)2(OPh)2 has been determined and reveals a pseudo-tetrahedral arrangement of the two η5-cyclopentadienyl and two phenoxide ligands around titanium. The Ti-O(Ph) distances are 1.907(3) Å and O-Ti-O is 98.1(2)°. The anti-tumour activities of Ti(η5-C5H5)Cl(OC6H4NH2-3)2, Ti(η5-C5H5)Cl(O2CPh)2 and Ti(η5-C5H5)2(O2C(S)C6H4-1,2) have been assessed in vitro using a panel of seven human tumour cell lines. © 1991.
