Preparation of the substituted salicylato of titanocene derivatives by the liquid–liquid interfacial reaction

The reaction of Cp2TiCl2 with several substituted salicylic acids in H2O+CHCl3 medium was discussed in detail. By interfacial reaction (methods 1–3), ten titanocene derivatives were prepared, respectively. The compounds were characterized by elemental analysis, UV–vis, IR and 1H-NMR. Based on the UV–vis spectrum, the following mechanism of reaction was proposed: first, Cp2TiCl2 in the organic phase interfacially with water in the aqueous phase to form its hydrolysate (such as [Cp2Ti(OH)(OH2)]+). When 5-sulfosalicylic acid (H2Ssal) is present in the reaction system, the hydrolysate transforms itself into [Cp2Ti(Ssal)]+ and the reaction is prompted. The resulting species undergoes an interfacial interaction with substituted salicylic acid to form the final complexes, which stay in the organic phase. Then the ‘Cp2Ti’ species return to the organic phase.