Bishydrazide Derivatives of Isoindoline as Simple Anion Receptors

Isoindoline has been investigated as a scaffold for the construction of anion receptors. A family of bishydrazide derivatives of isoindoline has been synthesized, and the anion-binding properties of these receptors were investigated both in solution and in the solid state. Enhanced affinity toward halides has been observed for isoindoline-based ligands compared to analogous pyrroledicarboxyamides. However, in the case of highly basic anions, the anion binding is accompanied by partial deprotonation of the receptors, which also leads to the color changes of ligands' solutions.