| 咔咯锰(Ⅴ)氧配合物与苯乙烯的氧原子转移反应机理 | |
| Oxygen Atom Transfer Reaction Mechanism between Manganese(Ⅴ)-Oxo Corrole Complexes and Styrene | |
| 摘要: 采用密度泛函理论B3LYP方法研究了咔咯锰（Ⅴ）氧配合物（MnⅤO corrole）与苯乙烯氧原子转移（oxygen atom transfer，OAT）反应途径和吸电子取代基的影响。计算结果发现氧原子进攻苯乙烯中双键的β碳原子形成过渡态，结合内禀反应坐标法（intrinsic reaction coordinate method，IRC）和最小能量交叉点（minimum-energy crossing point，MECP）计算，给出该反应发生直接氧转移的机理。咔咯大环中位连的吸电子五氟苯基可通过改变锰原子的亲电性，加大取代基与氧原子的静电排斥作用，增加MnⅤO corrole的氧化性。反应能垒随五氟苯基数目的增加而降低，且三重态的反应能垒明显低于单重态。体系可从单重态反应物开始，在MECP处易发生自旋翻转并形成三重态，然后以能量更低的三重态过渡态反应路径进行氧转移反应直至生成产物。 | |
| 关键词: 咔咯 锰氧配合物 苯乙烯 取代基效应 氧原子转移反应 最小能量交叉点 | |
| 基金项目: 国家自然科学基金项目（No.21671068）和广东省自然科学基金项目（No.S2012010008763）资助。 | |
| Abstract: The oxygen atom transfer (OAT) reaction pathway of the reaction between styrene and manganese(Ⅴ)-oxo corrole complexes (MnⅤO corrole) was investigated using the density functional theory B3LYP method. The calculation results showed that the oxygen atom attacked the β carbon atom of the olefinic double bond in styrene to form a transition state, and the direct oxygen atom transfer pathway was determined via the intrinsic reaction coordinate method (IRC) and the minimum -energy crossing point (MECP) calculation. The meso -pentafluorophenyl group of MnⅤO corrole can change the electrophilicity of the manganese atom and increase electrostatic repulsion between the substituent and the oxygen atom, leading to the improvement of oxygen transferability of MnⅤO corrole. With the increase of the pentafluorophenyl group number at the MnⅤO corrole, the reaction energy barrier decreases accordingly. Furthermore, the reaction energy barrier of the triplet state is significantly lower than that of the singlet state pathway, indicating that spin exchange is prone to occur and the reaction proceeds via triplet state pathway. In the OAT reaction pathway, the reactants in singlet state reach to MECP position firstly, and then change to the triplet state with spin over easily. After that, the reactants follow the triplet state pathway with a lower transition state to achieve the product. | |
| Keywords: corrole manganese-oxo complex styrene substituent effect oxygen atom transfer reaction minimum-energy crossing point | |
| 投稿时间：2021-05-16 修订日期：2021-10-20 | |
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| 曾琪,徐艳,陈华彬,许旋,徐志广,刘海洋.咔咯锰(Ⅴ)氧配合物与苯乙烯的氧原子转移反应机理[J].无机化学学报,2022,38(1):39-45. | |
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