C-H…π相互作用与[Co(pema)(amp)Cl]^(2+)体系优势构型异构体  

The Relationship of C-H...π Interaction and the Preference of Isomers in the [Co(pema)(amp)Cl]^(2+) System

作　　者：陶朱[1] 罗绪强[1] 张广义[1] 薛赛凤[1] 祝黔江[1] 

机构地区：[1]贵州大学应用化学研究所,贵州贵阳550025

出　　处：《贵州大学学报（自然科学版）》2003年第1期47-51,共5页Journal of Guizhou University:Natural Sciences

基　　金：贵州省省长基金资助项目。

摘　　要：用量子化学从头计算方法 ,在赝势基组RHF/LANL2DZ的水平上对 [Co(三元胺 ) (二元胺 )Cl]型配合物 - [Co( pema) (amp)Cl]2 +及 [Co( pema) (amp)OH]2 +( pema =N - ( 2 -吡啶基甲基 )乙二胺 ,amp =2 - (氨基甲基 )吡啶 )体系的十个可能的几何异构体 (四个经式异构体和六个面式异构体 )进行了结构优化及基态能量计算 ,对于 [Co( pema) (amp)Cl]2 +体系 ,f2’ ;f3;m3 ;m4四个异构体的基态能量比其他异构体低 ,其中f3为最低。在结构上 ,它们都含有C -H…π结构。而在合成实验中确实仅分离得到异构体f3。对于体系 [Co(pema) (amp)OH]2 +,基态能量较低者仍为f2’ ;f3;m3 ;m4,但此时f3是其中最高者。利用平衡碱水解方法 ,分离提纯得到的四个异构体 ,结构解析证实 ,它们正是理论计算结果中体系能量较低的四个异构体f2’ ,f3,m3和m4。这表明C -H…π相互作用在体系优势构型的形成中起着致关重要的作用。The computational results for the ten possible geometric isomers (four mer-isomers and six facial-isomers) in the \[Co(ptma)(amp)Cl\] 2+ and \[Co(ptma)(amp)OH\] 2+ systems have been obtained by using an ab initio at RHF/LANL2DZ level (pema = N-(2-pyridylmethyl)ethylenediamine;amp = 2-(Aminomethyl)pyridine) Although the total energies of the isomers f2', f3', m3, m4 are lower than other isomers in these two systems, For the \[Co(ptma)(amp)Cl\] 2+ system, the isomer f3 has the lowest of total energy in the four isomers, however, it is the highest one in the \[Co(ptma)(amp)OH\] 2+ system. Using equilibrate base hydrolysis, three new isomers have been obtained from the isomer f3. It is interpreted as consequences of the C-H...π interaction between the ligands in these isomers.

关 键 词：C-H…Π相互作用 [Co(pema)(amp)Cl]^2+体系 优势构型 异构体 量子化学从头计算 钴配合物 

分 类 号：O614.812[理学—无机化学] O641.6[理学—化学]