Fetrow Taylor V, Zgrabik Joshua, Bhowmick Rina, Eckstrom Francesca D, Crull George, Vlaisavljevich Bess, Daly Scott R
Department of Chemistry, The University of Iowa, E331 Chemistry Building, Iowa City, IA 52242, USA.
Department of Chemistry, The University of South Dakota, 414 East Clark Street, Vermillion, South Dakota, 57069, USA.
Angew Chem Int Ed Engl. 2022 Nov 7;61(45):e202211145. doi: 10.1002/anie.202211145. Epub 2022 Oct 12.
Qualitative differences in the reactivity of trivalent lanthanide and actinide complexes have long been attributed to differences in covalent metal-ligand bonding, but there are few examples where thermodynamic aspects of this relationship have been quantified, especially with U and in the absence of competing variables. Here we report a series of dimeric phosphinodiboranate complexes with trivalent f-metals that show how shorter-than-expected U-B distances indicative of increased covalency give rise to measurable differences in solution deoligomerization reactivity when compared to isostructural complexes with similarly sized lanthanides. These results, which are in excellent agreement with supporting DFT and QTAIM calculations, afford rare experimental evidence concerning the measured effect of variations in metal-ligand covalency on the reactivity of trivalent uranium and lanthanide complexes.
长期以来，三价镧系和锕系配合物反应活性的定性差异一直归因于金属 - 配体共价键的差异，但很少有实例对这种关系的热力学方面进行量化，特别是对于铀且不存在竞争变量的情况。在此，我们报道了一系列含有三价f族金属的二聚次膦酸二硼酸盐配合物，这些配合物表明，与具有类似尺寸镧系元素的同结构配合物相比，短于预期的U - B距离表明共价性增加，这会导致溶液中解聚反应活性出现可测量的差异。这些结果与支持性的密度泛函理论（DFT）和量子拓扑原子分子理论（QTAIM）计算结果高度一致，为金属 - 配体共价性变化对三价铀和镧系配合物反应活性的测量影响提供了罕见的实验证据。
