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采用从头算UHF方法在6-31G基组上研究了1，3-环己二烯与丙烯的加成反应所有可能的反应通道.优化得到了反应途径的所有驻点的几何构型.该反应可按分步和协同过程进行.分步过程的通道是能量最为有利的反应途径.对于分步过程形成exo和endo产物各存在两类分步加成机理，即“由丙烯双键端位碳先进攻环己二烯”机理和“由丙烯中心碳原子先进攻环己二烯”机理，共四条反应通道。它们均为途经一双自由基中间体的分步加成过程.反应的第一步为反应的速控步骤，计算的活化位垒在102-114kJ·mol-1之间.在从头算计算基础上，采用过渡态的微正则理论计算了分步过程四条通道的正则速率常数.计算结果表明：无论按照哪种反应机理进行，形成endo产物的通道的反应速率常数均大于形成exo产物的通道的值;无论形成哪类产物，均是“由丙烯双键端位碳先进攻环己二烯”机理的通道的速率常数大于“由丙烯中心碳原子先进攻环己二烯”机理的通道的值.但四条通道的速率常数相差不大，反应为竞争机制.
The ab initio calculation of the UHF method was used to study all the possible reaction pathways for the addition reaction of 1,3-cyclohexadiene with propylene on a 6-31G basis set. The geometry of all stationary sites of the reaction pathway was optimized. Step-by-step and synergistic processes can be carried out.The channels of the step-by-step process are the most energy-efficient reaction ways.There are two types of stepwise addition mechanisms for the formation of exo and endo products in the stepwise process, namely “ Advanced attack cyclohexadiene ”mechanism and“ advanced by the propylene center of carbon atom ring cyclohexadiene ”mechanism, a total of four reaction channels. All of them are stepwise addition processes via a pair of free radical intermediates.The first step of the reaction is the rate-controlling step of the reaction, and the calculated activation barrier is between 102 and 114 kJ · mol -1. On the basis of ab initio calculation , The regular rate constants of the four channels in the stepwise process were calculated using the micro-canonical theory of the transition state.The calculated results show that the reaction rate constants for the channels forming the endo product are greater than the values for the channels forming the exo product, regardless of the reaction mechanism ; No matter what kind of product is formed, the rate constant of the channel which is “the mechanism of first attacking cyclohexadiene by the end of carbon of a propylene double bond” mechanism is larger than the value of the channel of mechanism of first attacking cyclohexadiene by a propylene central carbon atom. However, the rate constant of the four channels is not much difference, the reaction mechanism for competition.