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8) was synthesized by the reaction of 2 equiv of lithium salt of 1 with TiCl 3 ‚3THF, followed by PbCl 2 oxidation. An X-ray crystal and molecular structure of titanocene dichloride substituted by fluorous ponytails, 8, was determined. The results show the applicability of fluorous chemistry methodology in early transition metal organometallic chemistry.

Mixtures of isomers of (perfluoroalkyl)tetramethylcyclopenta-1,3-dienes (CH 3 ) 4 C 5 H(CF 2 ) n CF 3 (n = 3, 5, 7, 9) were synthesized as precursors of new cyclopentadienyl ligands for organotransition metal catalysis in fluorous biphase media and characterized by combination of GC-MS and 13 C NMR spectroscopy. Rhodium(III) chloro complexes [Rh{(CH 3 ) 4 C 5 (CF 2 ) n CF 3 }Cl 2 ] 2 and rhodium(I) carbonyl complexes [Rh{(CH 3 ) 4 C 5 (CF 2 ) n CF 3 }(CO) 2 ] were prepared from the cyclopentadienes and molecular structure of [Rh{(CH 3 ) 4 C 5 (CF 2 ) 5 CF 3 }Cl 2 ] 2 was determined by X-ray diffraction. The ligands are electronically close to the unsubstituted cyclopentadienyl as shown by values of carbonyl stretching frequencies in the carbonyl complexes. Neither carbonyl frequencies nor NMR chemical shifts of the complexes are substantially affected by the length of the perfluoroalkyl chain.Catalysis in fluorous biphase systems (FBS), a method of catalyst separation alternative to catalyst heterogenization 1,2 or other biphase systems 3,4 , has gained considerable attention since the first report by Horváth and Rábai 5 in 1994. The interest in the topic, recently reviewed 6-8 , continues to grow. Although the majority of work still concentrates on solubilization of phosphine ligands, including the pioneering work of Horváth and Rábai, the range of available fluorophilic ligands broadens. It is somewhat surprising that research on solubilization of cyclopentadienyl ligands laggs behind