The rate of hydrolysis of the aromatic rings of Cp2TiX2 and the dimethylsubstituted derivatives (MeCp) 2TiX2 [X= Cl, O2CCH2NH3Cl], in aqueous solutions at pH 2–8 have been studied by 1H-NMR spectroscopy. Rapid hydrolysis of both the halide and cyclopentadienyl ligands in Cp2TiX2 [X= Cl, O2CCH2NH3Cl] occurs to give predominantly insoluble precipitates at pH 7. In contrast, under the same experimental conditions, the ...