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在一般非共轭体系中,取代基的诱导效应对于解释取代基衍生物的化学活性及某些物理性质都起着很重要的作用。人们对诱导效应的认识已有长远的历史,根据化合物的某些物理常数、反应平衡常数及反应速度常数等方面的事实,文献上已就取代基诱导效应的定性序列及定量关系作了介绍。其中Ingold的取代基诱导效应的定性序列应用最广泛;Hammett及Taft的取代基常数σ及σ是定量衡量取代基诱导效应最有成效的,但由于取代基常数σ及σ的数量很有限,有时也不一致;我国著名有机化学家蒋明谦等利用元素的电负性及原子共价半径两种基本常数,系统地计算了非共轭体系中取代基的诱导效应指数(Ⅰ),此指数直接地表达了分子结构与化学活性之间的定量关系,但计算也较繁琐。本文试
In a general non-conjugated system, the induction effect of a substituent plays an important role in explaining the chemical activity and some physical properties of a substituent derivative. People have a long history of the induction effect. Based on the fact that certain physical constants, reaction equilibrium constants and reaction rate constants of the compounds, the qualitative sequence and quantitative relationship of the substituent-induced effects have been introduced in the literature. Among them, Ingold has the most extensive application of the qualitative sequences of the substituent induction effect. The substituent constants σ and σ of Hammett and Taft are the most effective measures of the substituent induction quantitatively. However, due to the limited number of substituent constants σ and σ, Nor is it consistent. Jiang Mingqian, a famous organic chemist in China, systematically calculated the induction effect index (Ⅰ) of the substituent in the non-conjugated system by using the electronegativity of the element and the atomic covalent radius. The index expresses directly The quantitative relationship between molecular structure and chemical activity, but the calculation is more complicated. This article test