Pentamethylcyclopentadienylselenium derivatives VI: Synthesis and characterisation of ferrocenyl(pentamethylcyclopentadienyl)selenium

The novel mono(cyclopentadienyl)selenium derivatives, Se(C5Me4R)Fc (Fc = ferrocenyl, [Fe(η5-C5H5)(η5-C5H4)]; R = H or Me) have been prepared by treatment of diferrocenyl diselenide with LiC5Me4R, and characterised by NMR spectroscopy and mass spectrometry. The structure of Se(C5Me5)Fc has been confirmed by X-ray crystallography, and its redox properties have been examined by cyclic voltammetry. It reacts with [W(CO)5(THF)] to form [W2(μ-SeFc)2(CO)8] via C–Se bond cleavage.