Lithium Ion-Selective Binding Properties of a Conformationally Constrained Tris(spirotetrahydrofuran) Secured to an Inositol Orthoformate Platform

摘要

The C_(3v)-symmetric triaxially locked trispirotetrahydrofuran 2 binds Li~+ ions strongly and Na~+ ions much less effectively. The observed discrimination factor is attributed to greater structural preorganiztion and lower solvation prior to selective complexation, and particularly to the formation of a 2 : 1 sandwich complex involving lithium. ~(13)C NMR studies have defined a reluctance to form a 1 : 1 species when excess Li~+ is present.