Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106, Braunschweig, Germany.
Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany.
Chemistry. 2018 Dec 17;24(71):18922-18932. doi: 10.1002/chem.201804714. Epub 2018 Dec 11.
Several pnictogen dihalide complexes of the type (WCA-IDipp)EX (E=P, As, Sb; X=Cl, Br) that bear an anionic N-heterocyclic carbene ligand with a weakly coordinating borate moiety (WCA-IDipp, WCA=B(C F ) , IDipp=1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene) were prepared by salt metathesis reactions between the respective pnictogen trihalides EX and the lithium salt (WCA-IDipp)Li⋅toluene. Two-electron reduction of the dihalides (WCA-IDipp)EX with 1,3-bis(trimethylsilyl)-1,4-dihydropyrazine or elemental magnesium afforded the dipnictenes (WCA-IDipp) E , which display typical element-element double bonds as observed in diaryldiphosphenes, -arsenes and -stibenes. To provide an insight into the factors contributing to the structural stability of the pnictogen dihalide and dipnictene compounds, quantum chemical calculations were performed at the domain-based local pair natural orbital coupled-cluster (DLPNO-CCSD(T)) level. A local energy decomposition (LED) analysis of the interaction between the carbene and the pnictogen dihalide or dipnictene moiety demonstrates that London dispersion is an essential factor for the stabilization of these compounds.
几种类型的（WCA-IDipp）EX（E=P、As、Sb；X=Cl、Br）的磷族元素二卤化物配合物，它们带有带弱配位硼酸酯部分的阴离子 N-杂环卡宾配体（WCA-IDipp，WCA=B（CF ） ，IDipp=1,3-双（2,6-二异丙基苯基）咪唑啉-2-亚基）是通过各自的磷族元素三卤化物 EX 和锂盐（WCA-IDipp）Li⋅甲苯之间的盐交换反应制备的。二卤化物（WCA-IDipp）EX 与 1,3-双（三甲基甲硅烷基）-1,4-二氢吡嗪或元素镁的两电子还原得到了二磷烯（WCA-IDipp）E，其显示出与二芳基膦烯、-砷烯和-锑烯中观察到的典型的元素-元素双键。为了深入了解影响磷族元素二卤化物和二磷烯化合物结构稳定性的因素，在基于域的局部对自然轨道耦合簇（DLPNO-CCSD(T)）水平上进行了量子化学计算。对卡宾和磷族元素二卤化物或二磷烯部分之间相互作用的局部能量分解（LED）分析表明，伦敦色散是这些化合物稳定化的重要因素。
