有机化学中的异头效应  

Anomeric Effect in Organic Chemistry

作　　者：魏荣宝[1] 张大为[1] 梁娅[1] 卢俊瑞[1] 李红姬[1] 

机构地区：[1]天津理工大学化学化工学院,天津300191

出　　处：《有机化学》2008年第10期1664-1675,共12页Chinese Journal of Organic Chemistry

基　　金：国家自然科学基金(No.20472064);天津市自然科学基金(No.04304311)资助项目.

摘　　要：1955年Edward首次发现吡喃糖C(1)位的电负性强的取代基处于a键上,随后被Lemieux和Chü定义为异头效应.它是有机化学中最重要的立体电子效应之一,通常存在于有Lp-X-A-Y结构单元的分子中,其中X是带有孤对电子的电负性强的元素,A是一般元素,Y也是电负性强的元素,Lp是X的孤对电子,其轨道与A—Y键反平行.异头效应对分子的结构和反应活性有重要影响.综述了各类化合物中存在的异头效应、广义异头效应、反异头效应及在有机化学中的应用.The anomalous axial preference of electronegative substituents at the anomeric center C（1） of the pyranose ring was first noted by Edward in 1955 and was clearly defined as the anomeric effect by Lemieux and Chu, which plays a defining role in molecular conformation and reactivity, and is now recognized as one of the most important stereo-electronic effect in organic chemistry. The anomeric effect is recognized in an Lp-X-A-Y moiety as a preference for an antiperiplanar arrangement of the lone pair （Lp） and the A--Y bond, where X is a heteroatom, A is an element with intermediate electronegativity, and Y is a group with higher electronegativity （such as oxygen, nitrogen, fluorine, etc.）. In this paper, the anomeric effect, general- ized anomeric effect, reverse anomeric effect, endo-anomeric effect and exo-anomeric effect are described. The potential application of the anomeric effect is supplied.

关 键 词：异头效应 广义异头效应 反异头效应 氢键 

分 类 号：O621.1[理学—有机化学]