Facile Access to Silicon‐Functionalized Bis‐Silylene Titanium(II) Complexes

A series of unprecedented bis‐silylene titanium(II) complexes of the type [(η 5 ‐C 5 H 5 ) 2 Ti(LSiX) 2 ] (L=PhC(N t Bu) 2 ; X=Cl, CH 3, H) has been prepared using a phosphane elimination strategy. Treatment of the [(η 5 ‐C 5 H 5 ) 2 Ti(PMe 3 ) 2 ] precursor ( 1 ) with two molar equivalents of the N‐heterocyclic chlorosilylene LSiCl ( 2 ), results in [(η 5 ‐C 5 H 5 ) 2 Ti(LSiCl) 2 ] ( 3 ) with concomitant PMe 3 elimination. The presence of a SiCl bond in 3 enabled further functionalization at the silicon(II) center. Accordingly, a salt metathesis reaction of 3 with two equivalents of MeLi results in [(η 5 ‐C 5 H 5 ) 2 Ti(LSiMe) 2 ] ( 4 ). Similarly, the reaction of 3 with two equivalents of LiBHEt 3 results in [(η 5 ‐C 5 H 5 ) 2 Ti(LSiH) 2 ] ( 5 ), which represents the first example of a bis‐(hydridosilylene) metal complex. All complexes were fully characterized and the structures of 3 and 4 elucidated by single‐crystal X‐ray diffraction analysis. DFT calculations of complexes 3 – 5 were also carried out to assess the nature of the titanium–silicon bonds. Two σ and one π‐type molecular orbital, delocalized over the Si‐Ti‐Si framework, are observed.