摘要
对犤Co(3,3-tri)(amp)Cl犦2+四个几何经式异构体在不同条件下的取代及重排反应进行考察的实验结果表明,四个几何经式异构体碱性环境下的水解速率没有显著的差异,cis异构体比trans异构体约快20倍。实验中没有观察到面式异构体。在100℃二甲亚砜中加热的重排反应实验中可观察到异构体进行配体翻转的历程,如异构体m1-Cl转化为m4-Cl,m2-Cl转化为m3-Cl。m3和m4相对较稳定。利用量子化学从头计算法,在赝势基组RHF/LANL2DZ的水平上对该体系各异构体进行了基态能量、几何优化的计算,与已测定的异构体m3犤ZnCl4犦H2O和m4犤ZnCl4犦晶体结构参数比较,键长及键角的相对误差不超过3%。根据各异构体基态能量说明了各异构体的平衡分布;讨论了键角变形性大小与各异构体反应性大小的关系。
The kinetics of base hydrolysis reve als that the cis(N ￡(c)mer-isomers(m1or m?￡(c)are about 20-fold more re-active than the trans￡¨N a3￡(c)forms ￡¨m￡3or m￡′￡(c),there is no significant difference in reactivities between the cis￡¨Na3￡(c)and trans￡¨Nmer￡-isomers￡(r)No facial isomers have been found in the experiments￡(r)Rearrangements for DMSO as solvent at 100℃show ligand folding c ourses between the isomers,such as m1-Cl was observed to rearrange to m￡′￡-Cl or m￡2￡-Cl to m￡3￡-Cl￡(r)Relatively￡?m￡3and m￡′are stable￡(r)A comparison of t he measured structural parameters with an ab initio computational result for m￡3ZnCl ￡′and m￡′ZnCl ￡′￡¨RHF ￡ˉLANL￡2DZ optimised structure￡(c)reveals an maximum error of ?à￡3￡$￡(r)The results s uggest that equilibrium distributi ons of the geometric isomers relates to ground energy of them and reactiviti es of the isomers relates to their total bond angle distortions￡(r)
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2002年第6期563-570,共8页
Chinese Journal of Inorganic Chemistry
基金
贵州省省长基金
贵州大学科技基金资助项目
关键词
钴(Ⅲ)配合物
取代及重排
量化计算
构效关系
Co(Ⅲ)complex
substitution and rearrangement
calculation of quantum chemistry
structure and reactivity
