C₂-Bridged Titanocene−Ferrocenyl Complexes:  Synthesis, Reaction Chemistry, and Electrochemical Behavior

LiC⋮CFc ( 2; Fc = (η 5 -C 5 H 4 )(η 5 -C 5 H 5 )Fe) reacts with [Ti]Cl 2 ( 1a ) ([Ti] = (η 5 -C 5 H 4 SiMe 3 ) 2 Ti) in a 2:1 molar ratio to produce the C 2 -bridged titanocene−ferrocenyl complex [Ti](C⋮CFc) 2 ( 3 ). While treatment of heterotrinuclear 3 with Ni(CO) 4 ( 4 ) affords the heterotetranuclear tweezer complex {[Ti](C⋮CFc) 2 }Ni(CO) ( 5 ), reaction of 3 with NiCl 2 ( 6 ) yields Fc C⋮CC⋮C Fc ( 7 ) along with [Ti]Cl 2 ( 1a ) and Ni 0 in a redox reaction. 7 can also be synthesized in the chemical oxidation of 3 with 2 equiv of AgPF 6 . The electrochemical behavior of compounds 3 and 5 is discussed. The X-ray structure analysis of complex 3 is reported.