构象结构对于顺式-1,3-双甲基环己烷二级加氧反应影响的理论研究  

Theoretical Study of the Effect of Conformational Structures on the Secondary Oxidation Reactions of cis-1,3-Dimethylcyclohexane

作　　者：沈宇豪 田泽民 李伟[1] 纪亦轩 颜应文[1] SHEN Yuhao;TIAN Zemin*;LI Wei;JI Yixuan;YAN Yingwen(College of Energy and Power,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China)

机构地区：[1]南京航空航天大学能源与动力学院,南京210016

出　　处：《高等学校化学学报》2025年第3期97-110,共14页Chemical Journal of Chinese Universities

基　　金：江苏省自然科学基金(批准号:BK20200451)资助。

摘　　要：采用DLPNO-CCSD(T)/CBS//B3LYP/6-311++G(d,p)量子化学方法计算了顺式-1,3-双甲基环己烷自由基低温二级加氧反应的反应物、生成物和过渡态的分子结构、振动频率和单点能,构建了详细的反应势能面.基于过渡态理论,获得了主要基元反应的高压极限速率常数.结果表明,支链结构有利于过氧化氢过氧自由基(OOQOOH)的氢转移反应,其中,1,5-氢转移反应最占优势,与其直接裂解生成酮基化合物(KHP)+OH路径形成竞争关系.双过氧化氢自由基P(OOH)_(2)由OOQOOH经氢转移反应生成,主要裂解路径为环醚反应,其能垒因支链有增加趋势.基于RRKM/主方程方法获得的依压力变化的速率常数结果表明,压力对上述反应的速率常数影响较小.In this study,quantum chemistry method of DLPNO-CCSD(T)/CBS//B3LYP/6-311++G(d,p)was applied for low-temperature secondary oxidation reactions of cis-1,3-dimethylcyclohexane,to optimize molecular geometries,compute vibrational frequencies,and refine single point energies of all related reactants,transition states,and products.In this way,the detailed potential energy surfaces for titled reactions were constructed.High pressure limit rate constants of main reaction channels were calculated based on transition state theory.It was shown that side-chain tended to benefit H-transfer channels of hydroperoxy alkylperoxy radicals(OOQOOH),among which 1,5-H transfer reactions proved of great significance,competing with decomposition channel forming keto-hydroperoxides(KHP)and OH radical.Dihydrogen peroxide radicals[P(OOH)_(2)]resulted from H-transfer of OOQOOH radical mainly underwent cyclic ether reactions.The energy barriers of these reactions tended to increase due to side chain.Based on Rice-Ramsperger-Kassel-Marcus/master equation(RRKM/ME)method,the pressure-dependent rate constants were obtained,revealing that the effect of pressure on the rate constants of all above reactions was weak.

关 键 词：顺式-1 3-双甲基环己烷 构象分析 二级加氧 氢转移反应 环醚反应 速率常数 

分 类 号：O643.1[理学—物理化学]