Institute for Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (Cenide), University of Duisburg-Essen, Essen, Germany.
Institute of Organic Chemistry, Justus Liebig University, Giessen, Germany.
Nat Chem. 2020 Jul;12(7):608-614. doi: 10.1038/s41557-020-0456-x. Epub 2020 Apr 20.
Main-group-element compounds with energetically high-lying donor and low-lying acceptor orbitals are able to mimic chemical bonding motifs and reactivity patterns known in transition metal chemistry, including small-molecule activation and catalytic reactions. Monovalent group 13 compounds and divalent group 14 compounds, particularly silylenes, have been shown to be excellent candidates for this purpose. However, one of the most common reactions of transition metal complexes, the direct reaction with carbon monoxide and formation of room-temperature isolable carbonyl complexes, is virtually unknown in main-group-element chemistry. Here, we show the synthesis, single-crystal X-ray structure, and density functional theory computations of a room-temperature-stable silylene carbonyl complex [L(Br)Ga]Si:-CO (L = HC[C(Me)N(2,6-Pr-CH)]), which was obtained by direct carbonylation of the electron-rich silylene intermediate [L(Br)Ga]Si:. Furthermore, [L(Br)Ga]Si:-CO reacts with H and PBr with bond activation, whereas the reaction with cyclohexyl isocyanide proceeds with CO substitution.
主族元素化合物具有高能供体和低能受体轨道，能够模拟过渡金属化学中已知的化学键合模式和反应性模式，包括小分子活化和催化反应。单价第 13 族化合物和二价第 14 族化合物，特别是硅烯，已被证明是这方面的绝佳候选物。然而，过渡金属配合物最常见的反应之一是与一氧化碳的直接反应，形成在室温下可分离的羰基配合物，在主族元素化学中几乎未知。在这里，我们展示了室温稳定的硅烯羰基配合物[L(Br)Ga]Si:-CO（L = HC[C(Me)N(2,6-Pr-CH)]）的合成、单晶 X 射线结构和密度泛函理论计算，该配合物是通过富电子硅烯中间体[L(Br)Ga]Si:的直接羰基化获得的。此外，[L(Br)Ga]Si:-CO 与 H 和 PBr 发生键活化反应，而与环己基异氰化物的反应则进行 CO 取代。
