Department of Chemistry, University of California , Irvine, California 92697-2025, United States.
J Am Chem Soc. 2013 Sep 11;135(36):13310-3. doi: 10.1021/ja406791t. Epub 2013 Aug 28.
Flash reduction of Cp'3U (Cp' = C5H4SiMe3) in a column of potassium graphite in the presence of 2.2.2-cryptand generates crystalline [K(2.2.2-cryptand)][Cp'3U], the first isolable molecular U(2+) complex. To ensure that this was not the U(3+) hydride, [K(2.2.2-cryptand)][Cp'3UH], which could be crystallographically similar, the hydride complex was synthesized by addition of KH to Cp'3U and by reduction of H2 by the U(2+) complex and was confirmed to be a different compound. Density functional theory calculations indicate a 5f(3)6d(1) quintet ground state for the Cp'3U anion and match the observed strong transitions in its optical spectrum.
Cp'3U（Cp' = C5H4SiMe3）在 2.2.2-穴醚存在的钾石墨柱中发生闪光还原，生成结晶态的[K(2.2.2-穴醚)][Cp'3U]，这是第一个可分离的分子 U(2+)配合物。为了确保这不是 U(3+)氢化物[K(2.2.2-穴醚)][Cp'3UH]，因为它们在晶体学上可能相似，通过向 Cp'3U 中加入 KH 并通过 U(2+)配合物还原 H2 合成了氢化物配合物，并确认其为不同的化合物。密度泛函理论计算表明Cp'3U阴离子的基态为 5f(3)6d(1)五重态，与观察到的其光学光谱中的强跃迁相匹配。
