Anion response of dimeric hydrazide derivatives: Dependence on the nature of terminal substituents

The hunt for fluoride: Three dimeric hydrazide derivatives with nitro, phenyl, and methyl terminal substituents, all have colorless solution. When different anions were added, the sensing processes change the color of solution. Different terminal substituents bring various colors, and through conjugative effects they alter the acidity of compounds, as a consequence, change the affinity to different anions, so highly selective fluoride detection achieved.