Molecular Bis(chalcogenido) Titanates of Te, Se, and S.

A series of titanate cisoid bis(chalcogenidos) (Ch = Te, Se, and S) complexes supported by the β-diketiminate ligand BDI - = [ArNC(CH 3 )] 2 CH (Ar = 2,6- i Pr 2 C 6 H 3 ) are readily assembled via treatment of the Ti III precursor (BDI)Ti(CH 2 SiMe 3 ) 2 with 2.5 equiv of elemental "Ch" source and 1 equiv of reductant in the presence of crown-ether. In the absence of the electride, Te or S addition to (BDI)Ti(CH 2 SiMe 3 ) 2 results instead in the isolation of a mononuclear tellurido-tellurolate [(BDI)Ti(=Te)(TeCH 2 SiMe 3 )] and the bridging sulfido-thiolate complex [(BDI)Ti(SCH 2 SiMe 3 )(μ-S)] 2 , respectively. In the case of Se, the rare selenido-perselenoate complex [(BDI)Ti(=Se)(η 2 -SeSeCH 2 SiMe 3 )] was isolated. In addition to crystallographically and spectroscopically characterizing all of the complexes, we demonstrate the latter species to be likely intermediates in the formation of [(BDI)Ti(Ch) 2 ] - via the addition of electride.