Sugita Kengo, Yamashita Makoto
Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8603, Japan.
Chemistry. 2020 Apr 6;26(20):4520-4523. doi: 10.1002/chem.202000752. Epub 2020 Mar 13.
The reaction between a dialkyl-substituted alumanyl anion and [Y(CH SiMe ) (thf) ][BPh ] resulted in the formation of (dialkylalumanyl)yttrium complex 2, which exhibits the first 2-center-2-electron (2 c-2 e) Al-Y bond. The H and C NMR spectra of 2 together with an X-ray crystallographic analysis indicated a C symmetrical structure. DFT calculations on 2 revealed that its LUMO consists of overlapping 3 p- and 4 d-orbitals of the Al and Y atoms, respectively, and that the HOMO-LUMO gap is narrow. The UV/Vis spectrum of 2 exhibited a visible absorption at 432 nm, which suggests that the strong σ-donating and π-accepting character of the three-coordinate dialkylalumanyl ligand generates a colored d -complex that does not contain any π-electrons.
二烷基取代的铝基阴离子与[Y(CH₂SiMe₃)₃(thf)][BPh₄]之间的反应生成了（二烷基铝基）钇配合物2，它呈现出首个2中心2电子（2c-2e）的Al-Y键。2的¹H和¹³C NMR光谱以及X射线晶体学分析表明其具有C₂对称性结构。对2进行的密度泛函理论计算显示，其最低未占分子轨道（LUMO）分别由Al和Y原子的重叠3p和4d轨道组成，且最高已占分子轨道（HOMO）与LUMO之间的能隙较窄。2的紫外/可见光谱在432 nm处呈现出可见吸收，这表明三配位二烷基铝基配体强大的σ供电子和π吸电子特性生成了一种不含任何π电子的有色d⁰配合物。
