Postmetallocene Lanthanide-Hydrido Chemistry: A New Family of Complexes [{Ln{(Me3Si)2NC(NiPr)2}2(μ-H)}2] (Ln=Y, Nd, Sm, Gd, Yb) Supported by Guanidinate Ligands-Synthesis, Structure, and Catalytic Activity in Olefin Polymerization

The new family of Lewis base free hydrido complexes of rare‐earth metals supported by guanidinate ligands [{Ln{(Me3Si)2NC(NiPr)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 [D6]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{(Me3Si)2NC(NiPr)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). The alternative to lanthanide sandwiches: A new family of Lewis base free hydrido complexes of rare‐earth metals supported by guanidinate ligands [{Ln{(Me3Si)2NC(NiPr)2}2(μ‐H)}2] (Ln=Y, Nd, Sm, Gd, Yb; an example is shown here) has been synthesized and characterized. Complexes of Sm and Y have shown high catalytic activity in ethylene polymerization (1268 and 442 g mmol−1 atm−1 h−1, respectively).