Highly Efficient Chirality Transfer from Diamines Encapsulated within a Self-Assembled Calixarene-Salen Host
作者:Luis Martínez-Rodríguez、Nuno A. G. Bandeira、Carles Bo、Arjan W. Kleij
DOI:10.1002/chem.201500333
日期:2015.5.4
A calix[4]arene host equipped with two bis‐[Zn(salphen)] complexes self‐assembles into a capsular complex in the presence of a chiral diamine guest with an unexpected 2:1 ratio between the host and the guest. Effective chirality transfer from the diamine to the calix–salen hybrid host is observed by circular dichroism (CD) spectroscopy, and a high stability constant K2,1 of 1.59×1011 M−2 for the assembled
在手性二胺客体存在的情况下,带有两个双[Zn(salphen)]配合物的杯[4]芳烃主体自组装为荚膜复合体,主体与客体之间的比例意外达到2:1。通过圆二色性(CD)光谱观察到了有效的手性从二胺向杯形-salen杂交宿主的转移,并且确定了组装后的宿主-客体集合的高稳定常数K 2,1为1.59×10 11 M -2。实质合作因子α为6.4。与针对两种可能的非对映异构体所计算的那些相比,使用密度泛函计算来研究宿主-客体系统和实验CD谱的稳定性的起源。M,M异构体是优先形成的异构体。当前的系统为二胺的手性测定提供了希望,这一点已通过研究的底物范围以及二胺的ee与所观察到的Cotton效应的幅度之间的线性关系得到证明。