Directing the Cation Recognition Ability of Calix[4]arenes toward Asymmetric Phase‐Transfer Catalysis

Abstract

The recognition abilities of chiral calixarene hosts toward alkali cation guests have been exploited for the first time in asymmetric phase‐transfer catalysis. The binding affinities of a series of chiral α‐methylbenzylamine‐derived calix[4]arene‐amides toward Na+ guest have been determined by 1H NMR spectroscopic titration experiments. The good apparent association constant values are consistent with the macrocycles' catalytic efficiency in the asymmetric alkylation reaction of N‐(diphenylmethylene)glycine esters under phase‐transfer conditions.