Effects of Ionic Liquids on the Thermodynamics of Hydrogen Activation by Frustrated Lewis Pairs: A Density Functional Theory Study
Effects of Ionic Liquids on the Thermodynamics of Hydrogen Activation by Frustrated Lewis Pairs: A Density Functional Theory Study
复制标题
离子液体对受阻路易斯对氢活化热力学的影响：密度泛函理论研究。
DOI：
10.1002/cphc.202100093
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发表时间：
2021-04-16
期刊：
影响因子：
2.9
通讯作者：
Liu, Lei
中科院分区：
文献类型：
--
作者：
Liu, Xiaoqing;Li, Xue;Liu, Lei
阻挫刘易斯对（FLP）催化氢活化及其应用是近年来催化领域的研究热点之一。以往的研究表明，该反应的热力学是由FLP和溶剂的电子结构决定的。在这里，我们研究了由典型的FLP和离子液体（IL）组成的系统，这是众所周知的，因为它们的种类繁多，并且具有优异的溶剂效应。采用密度泛函理论（DFT）方法研究了分子内和分子间FLP对H-2活化的热力学行为。结果表明，离子液体中的总吉布斯自由能比甲苯中的总吉布斯自由能更负。通过热力学分配，我们发现离子液体更倾向于H-H断裂步骤，而不是质子附着、氢化物附着和两性离子稳定化步骤。此外，结果表明，这些影响是强烈依赖于类型的FLP，其中分子内的FLP比分子间的FLP更受影响。
Nowadays, hydrogen activation by frustrated Lewis pairs (FLPs) and their applications are one of the emerging research topics in the field of catalysis. Previous studies have shown that the thermodynamics of this reaction is determined by electronic structures of FLPs and solvents. Herein, we investigated systems consisting of typical FLPs and ionic liquids (ILs), which are well known by their large number of types and excellent solvent effects. The density functional theory (DFT) calculations were performed to study the thermodynamics for H-2 activation by both inter- and intra-molecular FLPs, as well as the individual components. The results show that the computed overall Gibbs free energies in ILs are more negative than that computed in toluene. Through the thermodynamics partitioning, we find that ILs favor the H-H cleavage elemental step over the elemental steps of proton attachment, hydride attachment and zwitterionic stabilization. Moreover, the results show that these effects are strongly dependent on the type of FLPs, where intra-molecular FLPs are more affected compared to the inter-molecular FLPs.