2-取代四氢吡咯的结构与旋光方向的关系  

Relationship Between Configuration and Rotatory Direction of 2-Substituted Tetrahydropyrrole

作　　者：尹玉英[1] 刘春蕴[1] 

机构地区：[1]北京石油化工学院,北京102617

出　　处：《北京石油化工学院学报》2005年第3期1-6,共6页Journal of Beijing Institute of Petrochemical Technology

基　　金：国家自然科学基金资助项目;项目号29542006

摘　　要：由于2取代四氢吡咯结构的信封式和扭曲式能差很小,在平衡体系中共存,2位上的取代基处于e键和a键的能差也较小,所以平衡体系是10种信封式和10种扭曲式构象的平衡混合物。每种构象都包括特有的数种螺旋,很难推断其旋光方向。为了将旋光方向与其构型联系在一起,假设平衡体系所有构象中环原子的平均构象位置处于同一平面中。按照平面式中存在的螺旋,利用螺旋理论可以估算2取代四氢吡咯的旋光方向,对于各种不同类型的这类化合物,都能准确地将化合物的构型和旋光方向联系在一起。和其它化合物一样,通过构型可以预测其旋光方向;通过旋光方向可以推断其C(2)的绝对构型。In equilibrium system, the envelope structure of 2-substituted tetrahydropyrrole coexists with the twist structure because of the small energy difference between them. Energy difference between substituent in 2-position existing as e-bond and a-bond is small too, therefore the equilibrium system becomes an equilibrium mixture of ten kinds of envelope and ten kinds of twist configuration. Because many kinds of specific helix are contained in every conformation, it is difficult for us to deduce its rotatory direction. In order to correlate rotatory direction with the configuration, we assume that the position of average conformation is in the same plane for ring atoms of all conformations in the equilibrium system. According to helix in plane formula, the rotatory direction of 2-substituted tetrahydropyrrole can be estimated by using the helix theory. Configuration can be correlated with rotatory direction for different kinds of such compound. Rotatory direction can be predicted from configuration, and absolute configuration of C（2） can be deduced from rotatory direction.

关 键 词：2-取代四氢吡咯 构型 旋光方向 螺旋理论 

分 类 号：O621.3[理学—有机化学]