C2-Bridged sandwich and half-sandwich entities with Ti(IV) and Cr(0) centers

The intense purple colored bi- and trimetallic complexes {Ti}(CH2SiMe3)[CC(η6-C6H5)Cr(CO)3] (3) ({Ti}=(η5-C5H5)2Ti) and [Ti][CC(η6-C6H5)Cr(CO)3]2 (5) {[Ti]=(η5-C5H4SiMe3)2Ti}, in which next to a Ti(IV) center a Cr(0) atom is present, are accessible by the reaction of Li[CC(η6-C6H5)Cr(CO)3] (2) with {Ti}(CH2SiMe3)Cl (1) or [Ti]Cl2 (4) in a 1:1 or 2:1 molar ratio. The chemical and electrochemical properties of 3, 5, {Ti}(CH2SiMe3)(CCFc) [Fc=(η5-C5H5)Fe(η5-C5H4)] and [Ti][(CC)nMc][(CC)mM′c] [n, m=1, 2; n=m; n≠m; Mc=(η5-C5H5)Fe(η5-C5H4); M′c=(η5-C5H5)Ru(η5-C5H4); Mc=M′c; Mc≠M′c] will be comparatively discussed.