Probing Donor–Acceptor Interactions in peri-Substituted Diphenylphosphinoacenaphthyl–Element Dichlorides of Group 13 and 15 Elements

Transmetalation reactions of ArLi with ECl3 (E = Al, P, In, Bi) and ArSnBu3 with ECl3 (E = B, Ga, Tl, As, Sb) gave rise to the formation of peri-substituted diphenylphosphinoacenaphthyl–element dichlorides ArECl2 (Ar = 6-Ph2P-Ace-5-), which were characterized by multinuclear NMR spectroscopy and X-ray crystallography. DFT calculations were performed on the compounds at relaxed gas-phase molecular geometries. For the series ArECl2 containing group 13 elements one structure type featuring regular Lewis pairs with short E–P peri distances (E = B, Al, Ga, In, Tl) was observed. For the series ArECl2 containing group 15 elements two structural types with very different peri distances (E = P, As, Sb, Bi) were found. The computed electron and pair densities were topologically analyzed according to the atoms-in-molecules (AIM) and electron localizability indicator (ELI-D) space-partitioning schemes, which facilitates the characterization of the peri interactions and also allows for monitoring minute electronic effects induced by different substituents and/or spatial arrangements.

芳基锂（ArLi）与三氯化物ECl3（E=Al、P、In、Bi）、三丁基芳基锡（ArSnBu3）与三氯化物ECl3（E=B、Ga、Tl、As、Sb）发生转金属化反应（Transmetalation），生成peri位取代的二苯基磷基苊基二氯化元素化合物ArECl2（Ar=6-Ph2P-Ace-5-）。上述产物通过多核核磁共振波谱法（multinuclear NMR）与X射线晶体衍射（X-ray crystallography）完成结构表征。针对该系列化合物，研究人员在弛豫气相分子几何构型下开展了密度泛函理论（Density Functional Theory, DFT）计算。对于包含第13族元素的ArECl2系列，观测到一类结构类型，其特征为规整路易斯对且存在较短的E-P peri位距离（对应E=B、Al、Ga、In、Tl）；而对于包含第15族元素的ArECl2系列，则发现两种结构类型，二者的peri位距离差异显著（对应E=P、As、Sb、Bi）。依据原子分子内原子（Atoms-in-Molecules, AIM）与电子定域性指示器（Electron Localizability Indicator-D, ELI-D）空间划分方案，对计算得到的电子密度与对密度进行了拓扑分析，该分析不仅可用于表征peri位相互作用，还能够监测由不同取代基及/或空间排布所诱导的微弱电子效应。