N,N′,N″,N‴-(2-Aminoethyl)-1,4,8,11-tetraazacyclotetradecane (TAEC) as a polyammonium receptor for anions

Abstract

The protonation behaviour of the polyammonium receptor N,N′,N″,N‴-(2-Aminoethyl)-1,4,8,11-tetraazacyclotetradecane (TAEC) and its interaction with ATP, [Fe(CN)₆]^4–, [Co(CN)₆]^3– and P₂O₇^4– have been studied potentiometrically in 0.15 mol dm^–3 NaClO₄ at 298.15 K as well as by ¹H, ¹³C and ³¹P NMR and electrochemical techniques. Emf data analysis indicates 1 : 1 stoichiometries for all the adducts formed. In the case of ATP and [Fe(CN)₆]^4– the stoichiometries are confirmed by using ³¹P NMR and electrochemical measurements, respectively. The results are compared with those of the related macrocyclic polyamine [24]aneN₈ and discussed in terms of the different ligand topologies.