摘要
在B3LYP/6-31+G(d,p)水平上优化了臭氧与丙烯酸丁酯反应体系各驻点物种的几何构型,并在相同水平上通过频率计算和内禀反应坐标(IRC)分析对过渡态结构及连接性进行了验证.采用G3//B3LYP方法对所有驻点进行单点能计算,构建了O3+CH3CH2CH2CH2OC(O)CHCH2反应体系的势能剖面,对Criegee自由基的单分子异构化反应进行了分析.研究结果表明,丙烯酸丁酯的臭氧化反应符合Criegee机理,存在两种反应路径,根据势能面分析,生成产物CH2OO和CH3CH2CH2CH2OC(O)CHO的反应是臭氧化物中间体(IM)裂解的优势路径.其Criegee自由基CH2OO和CH3CH2CH2CH2OC(O)CHOO因不具有α-CHn基团(n=1,2,3)而不可能发生单分子氢迁移异构化反应,只可通过环化异构化反应通道形成具有双氧环状结构的最终产物CH2O2和CH3CH2CH2CH2OC(O)CHO2.
The mechanism for the reaction between ozone and butyl acrylate as well as the isomerization of Criegee biradical were investigated at the G3B3//B3LYP/6-31 ＋G（d, p） level of theory. The geometries, vibrational frequencies of all stationary points involved in the title reaction were calculated at the B3LYP/6-31 ＋ G （d, p） level. Relationships of reactants, intermediates, transition states and products are confirmed by the intrinsic reaction coordinate （IRC） calculations. The calculated results show that the reaction between ozone and butyl acrylate follows Criegee mechanism. Two reaction pathways are found due to presence of the cleavage way of transition states and the pathway of CH2OO＋CH3CH2 CH2 CH20C（O）CHO formation,and it is proved that the most favorable pathway is the decomposition of a primary ozonide. Besides, Criegee biradical CH2OO and CH3CH2 CH2 CH20C（O） CHOO without an a- CH.group （n= 1,2,3） undergoes ring closure to dioxirane structure and the final products are CH2 02 and CH3 CH2 CH2 CH20C（O） CHO2 rather than unimolecular isomerization.
出处
《陕西师范大学学报（自然科学版）》
CAS
CSCD
北大核心
2013年第1期39-46,共8页
Journal of Shaanxi Normal University：Natural Science Edition
基金
国家自然科学基金资助项目(20873079)
关键词
丙烯酸丁酯
臭氧化反应
密度泛函理论
反应机理
n-butyl acrylate
ozonation
density functional theory（DFT）
reaction mechanism
