Chromogenic amides of pyridine-2,6-dicarboxylic acid as anion receptors
摘要:
The synthesis of simple, chromogenic pyridine-2,6-dicarboxylic acid amides, derivatives of isomeric nitroanilines and aminonitrophenols, and their ion binding properties are described. The ligands' response to ionic species was examined by naked eye and was studied with the use of UV-vis spectroscopy in DMSO and its mixture with water. The effect of the localisation and the type of the substituents in aromatic rings were discussed. H-1 NMR experiments were carried out to probe the mechanism of anion recognition, i.e. complexation via hydrogen bond formation versus ligand deprotonation. A selective response of N,N'-bis(2-hydroxy-4-nitrophenyl)pyridine-2,6-dicarboxamide (L5) towards dihydrogen phosphate was found in both DMSO and DMSO-water (95: 5) solvent mixture. The structure of N,N'-bis(2-hydroxy-5-nitrophenyl)pyridine-2,6-dicarboxamide (L4) was confirmed by X-ray crystallography.
Chromogenic amides of pyridine-2,6-dicarboxylic acid as anion receptors
作者:Ewa Wagner-Wysiecka、Jarosław Chojnacki
DOI:10.1080/10610278.2012.695789
日期:2012.9.1
The synthesis of simple, chromogenic pyridine-2,6-dicarboxylic acid amides, derivatives of isomeric nitroanilines and aminonitrophenols, and their ion binding properties are described. The ligands' response to ionic species was examined by naked eye and was studied with the use of UV-vis spectroscopy in DMSO and its mixture with water. The effect of the localisation and the type of the substituents in aromatic rings were discussed. H-1 NMR experiments were carried out to probe the mechanism of anion recognition, i.e. complexation via hydrogen bond formation versus ligand deprotonation. A selective response of N,N'-bis(2-hydroxy-4-nitrophenyl)pyridine-2,6-dicarboxamide (L5) towards dihydrogen phosphate was found in both DMSO and DMSO-water (95: 5) solvent mixture. The structure of N,N'-bis(2-hydroxy-5-nitrophenyl)pyridine-2,6-dicarboxamide (L4) was confirmed by X-ray crystallography.
Bioinspired Design of an Uncharged Ambipolar Helical Scaffold To Achieve Efficient Solid‐State Proton Conduction
Stereo-divergent packing of helicalscaffolds based on pyridine-2,6-dicarboxamide is observed in two different solid forms obtained from solvents of different polarity. Efficient solid-state protonconduction is observed in the yellow form, which has a homochiral molecular arrangement with closer intermolecular proximity, and spatial alignment of polar residues.