Postmetallocene Lanthanide–Hydrido Chemistry: A New Family of Complexes [{Ln{(Me₃Si)₂NC(N<i>i</i>Pr)₂}₂(μ‐H)}₂] (Ln=Y, Nd, Sm, Gd, Yb) Supported by Guanidinate Ligands—Synthesis, Structure, and Catalytic Activity in Olefin Polymerization

Abstract

Abstract The new family of Lewis base free hydrido complexes of rare‐earth metals supported by guanidinate ligands [{Ln{(Me 3 Si) 2 NC(N i Pr) 2 } 2 (μ‐H)} 2 ] (Ln=Y, Nd, Sm, Gd, Yb) was synthesized and structurally characterized. Single‐crystal X‐ray and solution NMR studies revealed that these complexes are dimeric in both solid state and in [D 6 ]benzene. The dimeric hydrido complexes can adopt eclipsed (Nd, Sm, Gd) or staggered (Y, Yb, Lu) conformations depending on the metal‐atom size. Catalytic activity of these [{Ln{(Me 3 Si) 2 NC(N i Pr) 2 } 2 (μ‐H)} 2 ] complexes in the polymerization of ethylene, propylene, and styrene has been investigated. Complexes of Sm and Y have high catalytic activity in ethylene polymerization (1268 and 442 g mmol −1 atm −1 h −1 , respectively).