Synergy between Experimental and Computational Chemistry Reveals the Mechanism of Decomposition of Nickel–Ketene Complexes,Journal of the American Chemical Society

当前位置： X-MOL 学术 › J. Am. Chem. Soc. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Synergy between Experimental and Computational Chemistry Reveals the Mechanism of Decomposition of Nickel–Ketene Complexes
Journal of the American Chemical Society ( IF 14.4 ) Pub Date : 2016-10-14 , DOI: 10.1021/jacs.6b08897
Nicholas D. Staudaher ₁ , Atta M. Arif ₁ , Janis Louie ₁

Affiliation

A series of (dppf)Ni(ketene) complexes were synthesized and fully characterized. In the solid state, the complexes possess η2-(C,O) coordination of the ketene in an overall planar configuration. They display similar structure in solution, except in some cases, the η2-(C,C) coordination mode is also detected. A combination of kinetic analysis and DFT calculations reveals the complexes undergo thermal decomposition by isomerization from η2-(C,O) to η2-(C,C) followed by scission of the C═C bond, which is usually rate limiting and results in an intermediate carbonyl carbene complex. Subsequent rearrangement of the carbene ligand is rate limiting for electron poor and sterically large ketenes, and results in a carbonyl alkene complex. The alkene readily dissociates, affording alkenes and (dppf)Ni(CO)2. Computational modeling of the decarbonylation pathway with partial phosphine dissociation reveals the barrier is reduced significantly, explaining the instability of ketene complexes with monodentate phosphines.

中文翻译：

实验和计算化学之间的协同作用揭示了镍 - 乙烯酮配合物的分解机制

合成并充分表征了一系列 (dppf) Ni(乙烯酮) 配合物。在固态下，配合物在整体平面构型中具有烯酮的 η2-(C,O) 配位。它们在溶液中显示出相似的结构，除了在某些情况下，还检测到 η2-(C,C) 配位模式。动力学分析和 DFT 计算的结合表明，复合物通过从 η2-(C,O) 异构化为 η2-(C,C) 进行热分解，然后断裂 C=C 键，这通常是限速并导致中间体羰基卡宾配合物。随后卡宾配体的重排限制了缺电子和空间大的烯酮的速率，并导致羰基烯烃配合物。烯烃很容易解离，得到烯烃和 (dppf)Ni(CO)2。

更新日期：2016-10-14

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南