A Linear Metallocene of Sc(II) Supported by [C5Me4(SiMe2tBu)]1– Ligands

Reduction of [C₅Me₄(SiMe₂^tBu)]₂ScI with KC₈ generates the first example of a neutral, linear metallocene of scandium analogous to ferrocene, namely [C₅Me₄(SiMe₂^tBu)]₂Sc. X-ray diffraction studies, spectroscopic analyses, and DFT calculations are consistent with a Sc(II) complex. [C₅Me₄(SiMe₂^tBu)]₂Sc reacts reversibly with N₂ to provide the end-on (N═N)^2– complex {[C₅Me₄(SiMe₂^tBu)]₂Sc}₂(μ-η¹:η¹-N₂) and gives a rare example of a crystallographically characterizable Sc(III) terminal hydroxide, namely [C₅Me₄(SiMe₂^tBu)]₂Sc(OH), as a hydrolysis product. The analogous linear Ca(II) metallocene [C₅Me₄(SiMe₂^tBu)]₂Ca was synthesized and characterized for comparison.