75173-44-3Relevant academic research and scientific papers
Potentiometric and AM1d studies of the equilibria between silver(I) and diaza-15-crown and diaza-18-crown ethers with nitrogen in different positions in various solvents
Kira, Jaromir,Niedzialkowski, Pawel,Ossowski, Tadeusz
, p. 180 - 190 (2013/11/19)
Complex formation and stability constants between typical and atypical diaza-15-crown and diaza-18-crown ethers with silver(I) were determined in methanol, acetonitrile and propylene carbonate by the potentiometric method. In two of the diaza crown ethers, AA-diaza-15 and AA-diaza-18-crown, two nitrogens in the macrocyclic ring replaced two consecutive oxygens instead of two opposite ones in the two other diaza crown ethers. It was found that complexes of 1:1 and 1:2 metal-to-ligand stoichiometry were formed. The solvent composition and cavity size of crown ethers significantly influences the stability constants of complexes. AA-diaza-15 and AA-diaza-18-crown ethers were examined for comparison with diaza-15-crown and diaza-18-crown ethers. AA-diaza crown ethers formed less stable 1:1 metal-to-ligand complexes with silver(I) than typical diaza crown ethers but their ability to form 1:2 metal-to-ligand complexes was stronger. The energetically most favorable structures of the 1:1 metal-to-ligand complexes were calculated and visualized by the AM1d method at the semiempirical level of theory.
SYNTHESIS OF N-UNSUBSTITUTED DI- AND TRIAZA CROWN ETHERS.
Maeda,Furuyoshi,Nakatsuji,Okahara
, p. 3073 - 3077 (2007/10/02)
Facile syntheses of di- and triaza crown ethers by intramolecular cyclization of oligoethylene glycols containing two or three imino groups or by their intermolecular cyclization with oligoethylene glycol bis(p-toluenesulfonate)s are described.
