Synthesis of titanocene derivatives catalyzed by 5-sulfosalicylic acid in a two-phase system

A new synthetic method featuring using 5 - sulfosalicylic acid as catalyst to prepare nine titanocene derivatives is reported. The title complexes wer e characterized by elemental analysis, UV - vis, IR and H-1 NMR spectroscop y. Based on the UV - vis spectrum, the mechanism of synthetic complexes is proposed as follows: first, Cp2TiCl2 in the organic phase reacts interfacia lly with 5 - sulfosalicylic acid in the aqueons phase to form an intermedia te. The resulting species undergoes an interfacial interaction with substit uted salicylic acid to form the final complexes, which stay in the organic phase. Then the 'Cp2Ti' species return to the organic phase while 5 - sulfo salicylic acid remains in the water phase.