Computational Design of Iron Diphosphine Complexes with Pendant Amines for Hydrogenation of CO2 to Methanol: A Mimic of [NiFe] Hydrogenase

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• 作者：Xiangyang Chen ; Dr. Yuanyuan Jing and Prof. Dr. Xinzheng Yang
• 刊名：Chemistry - A European Journal
• 出版年：2016
• 出版时间：June 20, 2016
• 年：2016
• 卷：22
• 期：26
• 页码：8897-8902
• 全文大小：1902K
• ISSN：1521-3765

文摘

Inspired by the active-site structure of the [NiFe] hydrogenase, we have computationally designed the iron complex [P^tBu₂N^tBu₂)Fe(CN)₂CO] by using an experimentally ready-made diphosphine ligand with pendant amines for the hydrogenation of CO₂ to methanol. Density functional theory calculations indicate that the rate-determining step in the whole catalytic reaction is the direct hydride transfer from the Fe center to the carbon atom in the formic acid with a total free energy barrier of 28.4 kcal mol⁻¹ in aqueous solution. Such a barrier indicates that the designed iron complex is a promising low-cost catalyst for the formation of methanol from CO₂ and H₂ under mild conditions. The key role of the diphosphine ligand with pendent amine groups in the reaction is the assistance of the cleavage of H₂ by forming a Fe−H^δ−⋅⋅⋅H^δ+−N dihydrogen bond in a fashion of frustrated Lewis pairs.