水溶剂环境下Eda酮式异构体消除超氧负离子自由基O^(-)_(2)·的反应机理

The Reaction Mechanism of Eda Ketone Isomer Eliminating Superoxide Anion Radical O^(-)_(2)·in Aqueous Solvent Environment

该文在M06-2X/SMD/6-311+G(d,p)水平上,研究了在水溶剂环境1 atm压力和310.15 K温度下Eda酮式异构体与超氧负离子自由基O^(-)_(2)·的反应机理.研究发现:Eda酮式异构体与O^(-)_(2)·的反应有抽H、加成以及单电子转移3种方式.反应势能面研究表明:抽H反应的自由能垒为38.0~176.1 kJ·mol^(-1),优势通道是O^(-)_(2)·抽取杂环H,反应能垒为38.0~41.0 kJ·mol^(-1).加成反应的自由能垒为84.2~196.6 kJ·mol^(-1),优势通道是O^(-)_(2)·加成到杂环与甲基相连的C原子上,反应能垒为84.2 kJ·mol^(-1).单电子从Eda酮式异构体向O^(-)_(2)·转移的反应的能垒为409.2 kJ·mol^(-1),该反应不能实现.研究结果表明:在水溶剂环境下Eda酮式异构体可通过提供杂环H以及甲基邻位C与自由基加成2种途径消除O^(-)_(2)·.

At the level of M06-2X/SMD/6-311+G(d,p),the reaction mechanism of Eda ketone isomer with superoxide anion radical O^(-)_(2)·is studied in aqueous solvent environment of 1 atmosphere pressure and 310.15 K temperature.The studies show that Eda ketone isomer reacts with O^(-)_(2)·in three ways that are H extraction,addition and single electron transfer.The study of reaction potential energy surface shows that the free energy barrier of H extraction is between 38.0 and 176.1 kJ·mol^(-1).The dominant channel is extraction of heterocyclic H by O^(-)_(2)·,its reaction energy barrier is between 38.0 and 41.0 kJ·mol^(-1).The free energy barrier of addition reaction is between 84.2 and 196.6 kJ·mol^(-1),the dominant channel is the addition of O^(-)_(2)·to the heterocyclic C atom attached to the methyl group,and the reaction energy barrier is 84.2 kJ·mol^(-1).The energy barrier of single electron transferring from Eda ketone isomer to O^(-)_(2)·is 409.2 kJ·mol^(-1),this reaction cannot be realized.The results show that Eda ketone isomers can eliminate O^(-)_(2)·by providing heterocyclic H and adding methyl ortho-C with free radicals in aqueous solvent.