Lower-rim versus upper-rim functionalization in di-ionizable calix[4]arene-crown-5 isomers. Synthesis and divalent metal ion extraction
作者:Yanfei Yang、Gaurav Arora、Fernando A. Fernandez、Jennifer D. Crawford、Kazimierz Surowiec、Eun Kyung Lee、Richard A. Bartsch
DOI:10.1016/j.tet.2010.12.006
日期:2011.2
Two series of di-ionizable calix[4]arene-crown-5 isomers in the cone conformation are synthesized to probe the effect of the pendant acidic group location on their metalion extraction properties. In one series, the ionizable groups are attached to the lower rim of the calix[4]arene scaffold, which orients them near the crown ether cavity. In the second series, the ionizable groups are connected to