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Published on: October 18, 2018
Accessing the +IV Oxidation State in Molecular Complexes of Praseodymium
Aurélien R Willauer1, Chad T Palumbo1, Farzaneh Fadaei-Tirani1
1Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
Abstract:
Out of the 14 lanthanide (Ln) ions, molecular complexes 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-Pr, with [N(C6H4Br)3][SbCl6], affords the Pr(IV) complex [Pr(OSiPh3)4(MeCN)2], 2-Pr, which is stable once isolated. The solid state structure, UV-visible spectroscopy, magnetometry, and cyclic voltammetry data along with the DFT computations of the 2-Pr complex unambiguously confirm the presence of Pr(IV).
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