Accessing the + IV Oxidation State in Molecular Complexes of Praseodymium.

@article{Willauer2020AccessingT,
  title={Accessing the + IV Oxidation State in Molecular Complexes of Praseodymium.},
  author={Aur{\'e}lien R. Willauer and Chad T. Palumbo and Farzaneh Fadaei‐Tirani and Ivica Živkovi{\'c} and Iskander Douair and Laurent Maron and Marinella Mazzanti},
  journal={Journal of the American Chemical Society},
  year={2020}
}
Out of the 14 lanthanide (Ln) ions, molecular com-plexes of Ln(IV) were known only for cerium and more recently terbium. Here we demonstrate that the +(IV) oxidation state is also accessible for the large praseodymium (Pr) cation. The oxidation of the tetrakis(triphenysiloxide) Pr(III) ate complex, [KPr(OSiPh3)4(THF)3], 1-PrPh, with [N(C6H4Br)3][SbCl6], affords the Pr(IV) complex [Pr(OSiPh3)4(MeCN)2], 2-PrPh, which is stable once isolated. The solid state structure, UV-visible spec-troscopy… 
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