Synthesis and anion binding properties of 1,8-disulfonamidocarbazole dipyrromethane Schiff-base macrocycle & its amine analogue

2015-11-18T00:00:00Z (GMT) by Feng Zhang Yu-hui Zhou Xiao-ping Bao
<p>A novel 1,8-disulfonamidocarbazole-dipyrromethane Schiff-base macrocycle (<b>1</b>) and its amine analogue (<b>2</b>) were designed and synthesised, and their anion binding properties were studied via UV–vis and <sup>1</sup>H NMR titration spectra. The obtained results showed that a small change in the macrocyclic structure (by reducing imines into the corresponding amines) produced a remarkable impact on its binding affinity and selectivity for anions. For example, macrocycle <b>1</b> displayed a 7.9:1 F<sup>−</sup>/H<sub>2</sub>PO<sub>4</sub><sup>−</sup> selectivity; however, its amine analogue <b>2</b> showed a 78.5:1 F<sup>−</sup>/H<sub>2</sub>PO<sub>4</sub><sup>−</sup> selectivity.</p>