摘要
采用二阶微扰理论的MP2/6-31G(d,p)方法对气相中烯丙基负离子与N2O的反应机理进行了理论计算研究,并在相同基组下进一步用CCSD(T)方法进行了单点能的校正.计算结果表明,该反应存在三条反应通道,产物分别为cis-CH2CHCNN-+H2O,trans-CH2CHCNN-+H2O和CH2CCH-+N2+H2O,其中生成cis-CH2CHCNN-和trans-CH2CHCNN-的两条通道为相互竞争的主反应通道,计算结果与实验相吻合.同时利用传统的过渡态理论,计算了各反应通道在298K时,速控步骤的反应速率常数k(T).
The gas-phase reaction mechanism of allyl anion with N2O was investigated at the MP216-31G（d,p） level of the MP2 theory. The single-point energies have also been refined at the CCSD （T）/6-31G （d,p） level to get more accurate energies using the MP2/6-31G（d,p） optimized geometries. The computational results indicated that the reaction involved three reaction pathways to produce cis-vinyl-diazomethyl anion, trans-vinyl-diazomethyl anion, and allenyl anion. The major competition channels of the reaction which produced cis-vinyl-diazomethyl anion, and transvinyl-diazomethyl anion all involved two steps of α-H migration. Furthermore, all these rate-determing steps are the second α-H migration and the barriers are 89.79 and 97.93 kJ·mol^-1, respectively. Distinctly, allenyl anion was formed through one α-H and one β-H migration and its rate-determing step was the rotation of the N^10-O^11 and N^9-C^3 bonds around N--N bond. The rate coefficients of the rate-determining step of all the reaction channels have also been calculated using statistic thermodynamics and conventional transition state theory at 298 K.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2007年第2期217-222,共6页
Acta Physico-Chimica Sinica
基金
甘肃省自然科学基金(329051-A25-021)资助项目
关键词
烯丙基负离子
反应机理
二阶微扰理论(MP2)
过渡态理论
Allyl anion
Reaction mechanism
Second-order Moller-Plesset perturbation theory （MP2）
Transition state theory
