当前位置: X-MOL 学术J. Comput. Chem. › 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.)
Rational design of pincer-nickel complexes for catalytic cyanomethylation of benzaldehyde: A systematic DFT study
Journal of Computational Chemistry ( IF 3 ) Pub Date : 2021-06-30 , DOI: 10.1002/jcc.26708
Moumita Dutta 1 , Hemant Kumar Srivastava 2 , Akshai Kumar 1, 3
Affiliation  

The current study dwells upon the efforts to computationally probe a phosphine-free pincer-nickel complex that would demonstrate an efficiency better than the reported phosphine-based pincer-nickel complex (iPr2POCNEt2)Ni(CH2CN) for cyanomethylation reaction. For this purpose, the mechanism of cyanomethylation of benzaldehyde was studied quantum mechanically for a series of 11 pincer-nickel complexes. The energetics of various intermediates and transition states involved in the catalytic cycle for each catalyst was compared with the corresponding energetics of the Miller's catalyst (iPr2POCNEt2)Ni(CH2CN) that is reported to accomplish the cyanomethylation at room temperature. While pincer complexes (iPr4NNN)Ni(CH2CN) and (iPr4NCN)Ni(CH2CN) containing strong σ-donating amines were found to fare poorly, pincer-nickel complexes (iPr2NCN)Ni(CH2CN) and (dmPheboxNCN)Ni(CH2CN) based on weaker σ-donating imines had energetics more favorable than the reported efficient catalyst (iPr2POCNEt2)Ni(CH2CN). While strong trans-influencing C as the pincer central atom was found to be pivotal for lowering the cyanomethylation kinetics, presence of a poor trans-influencing N proved to be detrimental on the overall energetics.

中文翻译:

用于催化苯甲醛氰甲基化的钳-镍配合物的合理设计:系统 DFT 研究

目前的研究集中在计算探测无膦钳形镍复合物的努力上,该复合物将证明比报道的基于膦的钳形镍复合物 ( i Pr2 POCN Et2 )Ni(CH 2 CN) 用于氰甲基化反应的效率更好。为此,对一系列 11 种钳形镍配合物进行了苯甲醛氰甲基化的量子力学研究。将每种催化剂催化循环中涉及的各种中间体和过渡态的能量与米勒催化剂 ( i Pr2 POCN Et2 )Ni(CH 2 )的相应能量进行比较CN)据报道在室温下完成氰甲基化。虽然发现含有强σ 供体胺的钳形配合物 ( i Pr4 NNN)Ni(CH 2 CN) 和 ( i Pr4 NCN)Ni(CH 2 CN)表现不佳,但钳形镍配合物 ( i Pr2 NCN)Ni(CH 2 CN) 2 CN) 和 ( dm PheboxNCN)Ni(CH 2 CN) 基于较弱的σ 供体亚胺具有比报道的高效催化剂 ( i Pr2 POCN Et2 )Ni(CH 2 CN)更有利的能量学。虽然强发现影响 C 作为钳形中心原子对于降低氰甲基化动力学至关重要,而不良反式影响 N 的存在被证明对整体能量学有害。
更新日期:2021-07-23
down
wechat
bug