# Isolation of Dysprosium and Yttrium Complexes of a Three-Electron Reduction Product in the Activation of Dinitrogen, the (N_{2})^{3−} Radical

dataset

posted on 12.08.2009, 00:00 by William J. Evans, Ming Fang, Gaël Zucchi, Filipp Furche, Joseph W. Ziller, Ryan M. Hoekstra, Jeffrey I. ZinkDyI

_{2}reacts with 2 equiv of KOAr (OAr = OC_{6}H_{3}(CMe_{3})_{2}-2,6) under nitrogen to form not only the (N_{2})^{2−}complex, [(ArO)_{2}(THF)_{2}Dy]_{2}(μ-η^{2}:η^{2}-N_{2}),**1**, but also complexes of similar formula with an added potassium ion, [(ArO)_{2}(THF)Dy]_{2}(μ-η^{2}:η^{2}-N_{2})[K(THF)_{6}],**2**, and [(ArO)_{2}(THF)Dy]_{2}(μ_{3}-η^{2}:η^{2}:η^{2}-N_{2})K(THF),**3**. The 1.396(7) and 1.402(7) Å N−N bond distances in**2**and**3**, respectively, are consistent with an (N_{2})^{3−}ligand, but the high magnetic moment of 4f^{9}Dy^{3+}precluded definitive identification. The Y[N(SiMe_{3})_{2}]_{3}/K reduction system was used to synthesize yttrium analogues of**2**and**3**, {[(Me_{3}Si)_{2}N]_{2}(THF)Y}_{2}(μ-η^{2}:η^{2}-N_{2})[K(THF)_{6}] and {[(Me_{3}Si)_{2}N]_{2}(THF)Y}_{2}(μ_{3}-η^{2}:η^{2}:η^{2}-N_{2})K, that had similar N−N distances and allowed full characterization. EPR, Raman, and DFT studies are all consistent with the presence of (N_{2})^{3−}in these complexes.^{15}N analogues were also prepared to confirm the spectroscopic assignments. The DFT studies suggest that the unpaired electron is localized primarily in a dinitrogen π orbital isolated spatially, energetically, and by symmetry from the metal orbitals.