Ordoñez Osvaldo, Yu Xiaojuan, Wu Guang, Autschbach Jochen, Hayton Trevor W
Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, California 93106, United States.
Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260, United States.
Inorg Chem. 2022 Sep 26;61(38):15138-15143. doi: 10.1021/acs.inorgchem.2c02304. Epub 2022 Sep 14.
The reaction of [Ln(NO)(THF)] (Ln = La, Ce) with 4 equiv of LiCCl in EtO resulted in the formation of the homoleptic lanthanide-aryl "ate" complexes [Li(THF)][La(CCl)] ([Li][]) and [Li(THF)][Ce(CCl)] ([Li][]). These complexes represent the first isolated homoleptic perchlorophenyl complexes for the lanthanides. In the solid state, both [Li][] and [Li][] exhibit octa-coordinate lanthanide centers, with four Ln-C σ-bonds and four Cl → Ln dative interactions involving the -Cl atoms of the CCl ligands. Despite this apparent steric saturation, both [Li][] and [Li][] are highly temperature sensitive and quickly decompose in solution at room temperature. Density functional calculations show that the Ln-C donation bonds feature only weak 4f participation (e.g., ∼1% 4f weight for []). Nonetheless, the C chemical shift of the C nuclei of [] includes ca. 8 ppm of deshielding from the spin-orbit interaction due to the participation of the 4f (and 5d) orbitals in the La-C bonds.
[Ln(NO)(THF)]（Ln = La、Ce）与4当量的LiCCl在EtO中反应，生成了均配型镧系芳基“酸根”配合物[Li(THF)][La(CCl)]（[Li][]）和[Li(THF)][Ce(CCl)]（[Li][]）。这些配合物是镧系元素首个分离得到的均配型全氯苯基配合物。在固态下，[Li][]和[Li][]均呈现八配位的镧系中心，具有四个Ln-C σ键以及四个涉及CCl配体-Cl原子的Cl→Ln配位相互作用。尽管存在这种明显的空间饱和现象，[Li][]和[Li][]对温度都高度敏感，在室温下于溶液中会迅速分解。密度泛函计算表明，Ln-C给予键仅具有较弱的4f参与（例如，对于[]，4f权重约为1%）。尽管如此，由于4f（和5d）轨道参与La-C键，[]中C核的C化学位移包括约8 ppm的自旋轨道相互作用引起的去屏蔽效应。
