取代基对有机反应活性的影响主要是通过电性效应和空间效应来实现的。所谓空间效应是指分子的空间结构给予分子性质的异常影响。在许多情况下,空间效应成为影响反应活性的主要因素,它能解释许多电性效应所不能解释的反应规律和反常现象。下面分七个方面加以讨论。 Substituents on the organic reactivity mainly through the electrical effect and space effect to achieve. The so-called spatial effect refers to the molecular structure of the molecular nature of the abnormal impact. In many cases, the spatial effect becomes a major factor affecting the reactivity and can explain the reaction rules and anomalies that many electrical effects can not explain. The following seven areas to be discussed.