Asymmetrically-substituted calix(4)arenes
Abstract
Asymmetric calix(4)arenes (5) consisting of three different phenolic units were obtained by fragment condensation either of a trinuclear compound (1) with a 2,6-bis(bromomethyl)phenol (2) or a dinuclear compound (3) with a bisbromomethylated dimer (4) in a dioxane–TiCl4 system.