C_(59)XH(X=N,B)自由基加成区域选择性的理论研究  

Theoretical Studies on the Regioselectivity of Radical Addition to C_(59) XH (X=N, B)

作　　者：梁云霄[1] 尚贞锋[2] 赵学庄[2] 

机构地区：[1]宁波大学化学系,宁波315211 [2]南开大学化学系,天津300071

出　　处：《化学学报》2005年第13期1161-1166,i001,共7页Acta Chimica Sinica

基　　金：国家自然科学基金(No.20073022)资助项目

摘　　要：用半经验的AM1方法,对C59XHCl2n(X=N,B;n=1～2)和C60H2Cl2n(n=1～2)的异构体进行几何构型全优化和振动频率计算,结合密度泛函B3LYP/6-31G*单点能计算确定各异构体的相对稳定性.对比C59XH(X=N,B)和C60H2的H2加成方式,计算结果表明H2或Cl2加在碳笼官能化部分的邻近位置在能量上都是有利的;C59NH和C59BH自由基多加成物区域选择性的差别可归因于N原子和B原子电子性质的不同;立体效应是导致H2和Cl2加成方式不同的主要原因.Semtempirical AM1 and B3LYP/6-31G* density functional theory methods have been used to examine the relative stabilities of various isomers Of C59XHCl2n, C60H2Cl2n and C59XH5, where X = N, B and n=1 similar to 2. The calculation results indicate that the energetically favored isomers of C59XHCl2n, C60H2Cl2n and C59XH5 are those isomers in which the first and/or the second H-2 or Cl-2 reactants are all attached to the carbons in the vicinity of the functionalized part of the cage. The difference in regioselectivities between C59NH and C59BH can be attributed to the difference in electronic nature between N and B atoms. And the difference in steric effect between H and Cl atoms may be the primary factor that results in the different addition patterns of hydrogenation and chlorination of C59NH and C59BH.

关 键 词：C59NH C59BH 自由基加成 区域选择性 相对稳定性 异构体 密度泛函 富勒烯 AML 

分 类 号：O621.25[理学—有机化学]