Anion receptors based on 4-nitrophenylhydrazone

Abstract

We have designed and synthesized new chromogenic anion receptors 1 and 2, which utilized 4-nitrophenylhydrazone as anion recognition moiety. UV-vis and H-1 NMR titration showed that receptors 1 and 2 bound anions utilizing two hydrazone N-H hydrogen bond and two C-H hydrogen bond. Despite the weak hydrogen bonding abilities of binding motifs, receptor 1 showed affinities for dihydrogen phosphate and acetate and receptor 2 showed relatively strong affinities for dihydrogen phosphate in polar solvent such as 5% DMSO in CH3CN. (C) 2016 Elsevier Ltd. All rights reserved.