锂氟类硅烯与乙烯加成反应的理论研究

A Theoretical Study on the Addition Reaction of Silylenoid H_2SiLiFand Ethylene

用从头计算方法研究了锂氟类硅烯与乙烯的加成反应Ｈ_２ＳｉＬｉＦ＋Ｃ_２Ｈ_４→Ｈ_２ＳｉＣ_２Ｈ４＋ＬｉＦ．该反应的过渡态和类卡宾与乙烯的反应相似。反应前后的能量差经零点能校正后仅为－２．４ｋＪ／ｍｏｌ（ＭＰ２／６－３１Ｇ￣＊／／６－３１Ｇ￣＊）．本文分析了孩反应的热力学和动力学性质，计算了反应热力学函数的变化、平衡常数、Ａ因子以及速率常数。

The addition reaction of silylenoid H_2SiLiF and ethylene,H_2SiLiF+C_2H_4→SiC_2H_6+LiF,has been studied by using ab initio calculations.The transition state is similar to that of carbenoid′s reaction.The difference of energies between reactants and products corrected by zero-point energies is-2.4kJ/mol(MP2/6-31G/*6-31G*).The thermodynamic and kinetic calculation have been done and the change in thermodynamic functions,equilibrium constants,factor A and rate constants of the reaction are given in this paper.