Yttrium Hydride Complex Bearing CpPN/Amidinate Heteroleptic Ligands: Synthesis, Structure, and Reactivity

Abstract

The reaction of the yttrium dialkyls (C5H4- PPh2=N (C6H3Pr2)-Pr-i)Y(CH2SiMe3)(2)(thf) (1) with an excess of N,N'-diisopropylcarbodiimide gave the yttrium monoalkyl complex (C5H4-PPh2=N-(C6H3Pr2)-Pr-i)Y(CH2SiMe3)[(PrN)-Pr-i= C(CH2SiMe3)-(NPr)-Pr-i] (2). 2 subsequently reacted with 1 equiv of PhSiH3 to generate the CpPN/amidinate heteroleptic yttrium hydride [(C5H4-PPh2=N (C6H3Pr2)-Pr-i)Y(CH2SiMe3)(2)-(NPr)-Pr-i](mu-H)}(2) (3). Hydride 3 showed good reactivity toward various substrates containing unsaturated C C, C-N, and N-N bonds, such as azobenzene, p-tolyacetylene, 1,4-bis(trimethylsily1)-1,3-butanediyne, N,N'-diisopropylcarbodiimide, and 4-dimethylaminopyridine, affording the yttrium hydrazide complex 4 with a rare eta(2)-Cp bonding mode, yttrium terminal alkynyl complex 5, yttrium eta(3)-propargyl complex 6, yttrium amidinate complex 7, and yttrium 2-hydro-4-dimethylaminopyridyl product 8, respectively.