摘要
长期以来,化学家一直认为化合物在D线下的旋光性与其立体结构无关,并常以乳酸及其相同构型的衍生物的旋光性变化为例证。但是物质的性质是由其结构决定的,因此,所有光学活性化合物包括乳酸及其衍生物在内,它们的旋光性都应由其立体结构(构型和构象)所决定。过去没有找到这种关系的原因是:(1)没有认识到螺旋结构是导致旋光性的根本原因;(2)忽视了不同条件下的构象变化。构型相同的化合物,其优势构象不一定相同。同一化合物在不同溶剂中的构象变化是很大的。借助于构象分析,利用螺旋理论可以证明,乳酸及其衍生物的旋光性与其立体结构的关系是十分密切的。
For a long time, chemists have considered that there is no relationship between the optical activity of compounds under sodium D line (589 nm) and their stereostructure, and often took the optically active change of lactic acid and its derivatives (with the same configuration) as an example. As matter of fact, properties of materials are determined by the structure. Therefore , for all the optically active compounds including the lactic acid and its derivatives, the optical activity must be determined by their stereostructure (configuration and conformation). There are two reasons for not finding out the relationship between stereostructure and optical activity in the past. Firstly, it has not been realized that the helix structure was the essential cause of optical activity; secondly, changes in conformation under different conditions were neglected. It is uncertain that compounds with the same configuration have the same predominant conformation. The conformation of one compound may easily be changed in different solvents. Based on the helix theory and by means of conformational analysis, it can be proved that there is a close relation between optical activity and stereostructure of lactic acid and its derivatives.
出处
《北京石油化工学院学报》
2002年第1期12-15,共4页
Journal of Beijing Institute of Petrochemical Technology
基金
国家自然科学基金 29542006
关键词
乳酸
衍生物
立体结构
构象
旋光性
螺旋理论
lactic acid
stereostructure
conformation
optical activity
helix theory
