Density functional theoretical studies on effect of intramolecular hydrogen bonds on reduction of nitrophenols
Density functional theoretical studies on effect of intramolecular hydrogen bonds on reduction of nitrophenols
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分子内氢键对硝基酚还原作用的密度泛函理论研究
DOI：
10.1007/s40242-017-7066-1
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发表时间：
2017
影响因子：
3.1
通讯作者：
Wang Lianjun
中科院分区：
文献类型：
--
作者：
Zhang Hongmei;Liu Yan;Ma Fangping;Qiu Wei;Lei Bo;Shen Jinyou;Sun Xiuyun;Han Weiqing;Li Jiansheng;Wang Lianjun
分子内氢键(IMHBs)可以导致硝基苯酚(NPs)的不同物理化学性质，从而决定其环境行为。本文采用密度泛函理论(DFT)方法研究了IMHB对一系列硝基苯酚分子构型和性质的影响，以揭示IMHB与硝基苯酚还原反应的关系。几何构型优化和分子中原子(AIM)分析的结果表明，邻位取代的硝基苯酚中存在较强的IMHBs，其稳定性可以显著提高。在比较硝基苯酚异构体的ELUMO和绝热电子亲和能(AEA)时，IMHBs的存在有利于NPs的还原降解，这与先前的研究一致。为了深入了解IMHBs对这些分子还原降解行为的影响机理，计算了这些硝基苯酚异构体的凝聚亲电性Fukui指数(f-)、天然电荷和Wiberg键级。计算表明，由于IMHBs的形成，硝基上O原子的亲电活性显著提高，从而增强了O-取代NPs的还原降解能力。
Intramolecular hydrogen bonds(IMHBs) can lead to different physicochemical characteristics of nitrophenols(NPs) that determine their environmental behavior. In the present work, to reveal the relationship between IMHB and nitrophenol reduction, the effects of IMHB on the molecular geometries and properties of a series of nitrophenols were investigated with density functional theory(DFT) calculations. The results of the geometry optimization and atoms-in-molecules(AIM) analysis indicate relatively strong IMHBs inortho-substituted nitrophenols, whose stability could be significantly improved. In comparing theELUMOand adiabatic electron affinities(AEA) of the nitrophenol isomers, the presence of IMHBs benefited the reductive degradation of NPs, consistent with a previous study. To gain an insight into the effect mechanism of IMHBs on the reductive degradation behavior of these molecules, the condensed electrophilicity Fukui index(f–), natural charges and Wiberg bond orders of these nitrophenol isomers were calculated. The calculations indicate that the electrophilic reactivity activity of the O atom on the nitro group could be significantly improved due to the formation of IMHBs, which results in the enhanced reductive degradation ofortho-substituted NPs.