Lipophilic bis(crown ether) derivatives of 15-crown-5 and 18-crown-6 as neutral carriers of lon-selective electrodes

Abstract

Lipophilic bis(crown ethers) containing 15-crown-5 and 18-crown-6 rings were synthesized so as to obtain excellent neutral carriers for K⁺- and Cs⁺-selective electrodes, respectively. The K⁺-selective electrode based on the dodecylmethylmalonate of bis (15-crown-5), (I)(n= 1, R = Me), exhibited eminent electrode properties, proving of great practical use, while the Cs⁺-selective electrode of the bis(18-crown-6) derivative (I)(n= 2, R = Me) did not give results as good as expected. The electrochemical selectivities of the K⁺ electrode based on the dodecylmalonate of bis(15-crown-5), (I)(n= 1, R = H), and octadecanoyloxymethyl-15-crown-5 (II) are also discussed.