论文部分内容阅读
在甲醇钠的作用下,进行了脂肪腈类与甲醇的加成反应。实验结果表明:加成反应百分率与腈分子中烷基的诱导效应指数形成一正 S 型曲线,而反应的平衡常数及速度常数的对数则分别与烷基的诱导效应指数形成直线关系。根据转化率 S 型曲线上 I_(50)点的位置(10~3I_(50)=10),可以肯定所有烷基腈在这个反应中的转化率都很低,而且反应速度很慢;在卤素、羧基及氰基取代烷基腈中,α-取代物反应迅速且转化率高,但取代基在γ-位置以外,则情况与简单烷腈相近。蒋化率曲线的正 S 走向及速度常数与平衡常数对数的直线的正倾斜度,均表明这个反应是甲醇对腈的亲核子加成反应。
Under the action of sodium methoxide, the addition reaction of aliphatic nitriles and methanol was carried out. The experimental results show that the percentage of addition reaction forms a positive S-curve with the induction effect index of alkyl in the nitrile molecule, and the logarithm of equilibrium constant and velocity constant of reaction are linear with the induction index of alkyl respectively. According to the position of I_ (50) point on the S curve (10 ~ 3I_ (50) = 10), we can be sure that all of the alkylnitriles have very low conversion in this reaction and the reaction rate is very slow. , Carboxyl and cyano-substituted alkylnitriles, the α-substituents react rapidly and have high conversions, but the substituents are in the γ-position and are similar to the simple ones. The positive S-direction and the positive slope of the logarithm of the rate constant to the logarithm of the equilibrium constant indicate that this reaction is a nucleophilic addition reaction of methanol to nitrile.