期刊
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
卷 124, 期 28, 页码 8329-8336出版社
AMER CHEMICAL SOC
DOI: 10.1021/ja0203465
关键词
-
The monovalent cations of Na+, K+, Rb+, and Cs+ derived from the highly electropositive alkali metals represent prototypical charged spheres that are mainly subject to relatively simple electrostatic and solvation (hydration) forces. We now find that the largest of these Rb+ and Cs+ are involved in rather strong cation...pi(arene) interactions when they are suitably disposed with the ambifunctional hexasubstituted benzene C6E6. The ether tentacles (E = methoxymethyl) allow these cations to effect eta(1)-bonding to the benzene center in a manner strongly reminiscent of the classical a-arene complexes with positively charged electrophiles where Z(+) = CH3+, Br+, Cl+, Et3Si+, etc. The somewhat smaller potassium cation is involved in a similar M+...pi(arene) interaction that leads to eta(2)-bonding with the aromatic center in the pi-mode previously defined in the well-known series of silver(l)/arene complexes. We can find no evidence for significant Na+...pi(arene) interaction under essentially the same conditions. As such, the sigma-structure of the Rb+ and Cs+ complexes and pi-structure of the K+ complex are completely integrated into the continuum of sigma-pi bondings of various types of electrophilic (cationic) acceptors with arene donors that were initially identified by Mulliken as charge-transfer.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据