异头效应研究进展  

The Research Progress on the Study of the Anomeric Effect

作　　者：刘涛[1] 

机构地区：[1]济宁学院化学与化工系,山东曲阜273155

出　　处：《济宁学院学报》2011年第3期16-19,共4页Journal of Jining University

基　　金：山东省自然科学基金(ZR2010BQ031);山东省高等学校科技计划项目(J09LB54);济宁学院青年基金(2009QNKJ08)

摘　　要：在MP2/aug-cc-pVTZ水平上用从头算法研究了卡宾化合物XC:CH2F(X=CH3,NH2,OH)单重态的异头效应.计算表明,在所有情况下,顺式构象都比反式构象更稳定.卡宾孤电子对与C2-F反键轨道之间负的超共扼效应(lp(C:)→σ*(C2-F))稳定了C2-F键相对于卡宾孤对的反式构象.在XC:CH2F单重态中,由于异头效应σ*(C2-F)与C1-C2和C2-F键长线性相关的很好.Ab initio calculations up to MP2/aug-cc-pVTZ level have been carried out to study the anomeric effect in carbene compound XC：CH2F（X = CH3,NH2,OH,respectively） of singlet state and triplet state.The calculations indicate that the gauche conformers are more stable in every case than that of the corresponding anti conformers.The negative hyperconjugation between the carbene lone pair and the antibonding C2-F orbital（lp（C：）→σ＊（C2-F）） results in stabilization of the antiperiplanar orientation of the C2-F bond relative to the carbene lone pair.In the singlet state of XC：CH2F,σ＊（C2-F） is well correlated with C1-C2 and C2-F bond length due to anomeric effect.

关 键 词：异头 XC:CH2F MP2 

分 类 号：O541[理学—物理]