Inorganic Chemistry, Vol.55, No.11, 5684-5692, 2016
Cerium(III) and Uranium(IV) Complexes of the 2-Fluorophenyl Trimethylsilyl Amide Ligand: C-F -> Ln/An Interactions that Modulate the Coordination Spheres of f-Block Elements
2-fluorophenyl trimethylsilyl amide, N(SiMe3)-(C6H4F)(-) was shown to engage in stronger C-F -> Ce-III interactions than pentafluorophenyl trimethylsilyl amide, N(SiMe3)(C6F5)(-), through a comparative study of the Ce-III model complexes Ce[N(SiMe3)(C6H4F)](3) (1-F-1) and Ce[N-(SiMe3)(C6F5)](3) (1-F-5). The presence of multiple C -F -> U-IV interactions led to complexes 2-X (X = Cl, C equivalent to CPh, OMe) with threefold geometries, featuring a trigonal pyramidal UN3Cl core in the solid-state structures. Density functional theory calculations were applied to 2-Cl to investigate the strength of the C-F -> U-IV interactions and the influence of such interactions on resulting geometries.