Synthesis, X-ray crystal structure, and cation transfer properties of a calix[4]arene tetraketone, a new versatile molecular receptor

Abstract

Treatment of p-t-butylcalix[4]arene with bromoacetone–potassium carbonate yields a crystalline tetraketone which shows exceptionally high phase-transfer activity towards alkali metal cations in aqueous solutions; X-ray and n.m.r. analyses show that the receptor possesses a cone conformation in which the carbonyl groups are pre-organised for ion binding.