H.C. Brown Laboratory, Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA.
Department of Chemistry, Supercomputing Institute, and Chemical Theory Center, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Nat Chem. 2017 Sep;9(9):850-855. doi: 10.1038/nchem.2767. Epub 2017 Apr 24.
Actinyl species, [AnO], are well-known derivatives of the f-block because of their natural occurrence and essential roles in the nuclear fuel cycle. Along with their nitrogen analogues, [An(NR)], actinyls are characterized by their two strong trans-An-element multiple bonds, a consequence of the inverse trans influence. We report that these robust bonds can be weakened significantly by increasing the number of multiple bonds to uranium, as demonstrated by a family of uranium(VI) dianions bearing four U-N multiple bonds, [M][U(NR)] (M = Li, Na, K, Rb, Cs). Their geometry is dictated by cation coordination and sterics rather than by electronic factors. Multiple bond weakening by the addition of strong π donors has the potential for applications in the processing of high-valent actinyls, commonly found in environmental pollutants and spent nuclear fuels.
锕酰物种 [AnO] 是 f 区元素的知名衍生物，因为它们在天然存在和核燃料循环中起着重要作用。与它们的氮类似物 [An(NR)] 一样，锕酰物种的特征是具有两个强的反式锕元素多重键，这是反式影响的结果。我们报告说，通过增加铀的多重键数量，可以显著削弱这些坚固的键，这由一系列具有四个 U-N 多重键的铀 (VI) 二阴离子 [M][U(NR)]（M = Li、Na、K、Rb、Cs）证明。它们的几何形状由阳离子配位和空间位阻决定，而不是由电子因素决定。通过添加强 π 给体来削弱多重键有可能应用于高价锕酰的处理，高价锕酰通常存在于环境污染物和乏核燃料中。
