Five new hydroxy-bearing dibenzoazacrown ethers were synthesized by a convenient route. Reaction of salicyladehyde with epichlorohydrin gave 1,3-bis(2-formylphenoxy)-2-propanol, which condensed with diamino compounds followed by a one pot reduction of the corresponding bis-imine derivatives without isolation to afford the hydroxy-bearing dibenzoazacrown ethers. All of the ligands were identified by EA, IR and NMR. Some transition metal complexes were prepared and characterized by elemental analysis, IR and molar conductance. The transport of alkali metal cations across a liquid membrane by using these ligands as ion carrier was also studied.
Zhao, B., Wu, Y. J., Tao, J. C., Yuan, H. Z., & Mao, X. A. (1996). Studies on the syntheses of hydroxy-bearing benzo-azacrown ethers and their complexing behaviour. Polyhedron, 15(7), 1197–1202. https://doi.org/10.1016/0277-5387(95)00262-6