range from −1 kcal/mol for the addition of CCl2 to tetramethylethylene to 11 kcal/mol for the addition of FCOMe to acrylonitrile. A generally satisfactory analysis of major trends in the evolution of carbenic structure and reactivity is afforded by qualitative applications of frontier molecular orbital theory, although the observed entropies of activation appear to fall in a counterintuitive pattern.
我们提出了六种碳烯(CCl 2,CClF,CF 2,ClCOMe,FCOMe和(MeO)2 C)与六种烯烃(四甲基
乙烯,
环己烯,
1-己烯,
丙烯酸甲酯,
丙烯腈和α)反应的实验激活参数-
氯丙烯腈)。添加CCl 2的活化能范围为-1 kcal / mol将FCOMe加到
丙烯腈中时,将其转化为四甲基
乙烯至11kcal / mol。通过定性应用前沿分子轨道理论,可以对羧基结构和反应性演变的主要趋势进行总体上令人满意的分析,尽管观察到的激活熵似乎是违反直觉的。分析计算的
环丙烷化过渡态参数表明(MeO)2 C对α-
氯丙烯腈具有显着的亲核选择性。