稀土中性苯配合物的化学键及其配位活化

用INDO方法研究了稀土中性η~6-苯配合物的电子结构及其化学键的配位活化。计算结果表明, NdCl_3和AlCl_3通过Cl桥键联的配位作用降低了钕离子的Lewis酸性和Nd-Cl之间的电荷差及其键的极性, 导致NdCl_3在苯中溶解度的增大, 从而有利于苯分子跟钕离子的配位反应。苯跟钕离子的配位降低了其C—C和C—H键的强度, 使苯环上的烷基化反应易于进行。

Bonding and Coordinating Activation of Neutral η6-Benzene Complex of Rare Earth

The electronic structure and coordinating activation of chemical bonds of η~6-benzene complex of neodymium have been studied by INDO method. The results show that the coordination of NdCl_3 to AlCl_3 through six μ_2-Cl may decrease the Lewis acidity of the Nd ion, the charge difference on Nd and Cl, and polarity of Nd—Cl bonds, which leads to the increasing of the solubility of NdCl_3 in benzene and the stability of the η~6-benzene complex of neodymium. The coordination of benzene molecule to neodymium ion decreases the strength of C—C and C—H bonds in benzene and enhances the alkylation affinity of the benzene ring obviously.