41757-95-3Relevant articles and documents
Solvent Extraction of Lanthanoid(III) Picrates with a Bis(crown ether): Enhanced Extractability through Double-sandwich Complexation
Inoue, Yoshihisa,Nakagawa, Kazuharu,Hakushi, Tadao
, p. 2279 - 2281 (1993)
Solvent extractions of aqueous light lanthanoid(III) picrates (La-Gd) with 1,8-dioxooctamethylenebis(4'-benzo-15-crown-5) 4 were conducted at low ionic strength in the absence of dense background salts.Possessing two crown ether units, the bis(crown ether) gave much higher extractabilities for the lanthanoids than did the reference ligand, 4'-acetylbenzo-15-crown-5 3, or related ligands 15-crown-5 1 and benzo-15-crown-5 2, although the profile of the relative cation-selectivity sequence became flat.Unexpectedly, quantitative solvent extraction studies revealed that the cation:ligand stoichiometry of the complex is not 1:1 but 1:2.This indicates that the enhanced extractabilities and the decreased cation selectivity arise not from the conventional intramolecular sandwich complexation but from the unique bimolecular double-sandwich complexation incorporating four crown ether units wrapping around a partially hydrated lanthanoid ion that has to be shielded effectively from the surrounding organic solvent molecules.
Parish et al.
, p. 4577 (1978)
Lipase-mediated resolution of racemic benzo-15-crown-5 ether derivatives
Kijima, Tatsuro,Moriya, Takanori,Kondoh, Eiki,Izumi, Taeko
, p. 2125 - 2127 (2000)
Racemic large secondary alcohol, 4'-hydroxyethyl-benzo-15-crown-5-ether, (±)-1 was kinetically resolved in high optical yield by asymmetric transformation with Candida antarctica lipase and Pseudomonas cepacia lipase. (C) 2000 Elsevier Science Ltd.
Studies on the photochemical behavior of N-salicylidenaniline in chloroform
Zhao, Liyan,Xia, Wujiong,Gou, Baoquan,Lu, Yu,Yang, Chao,Li, Dazhi
, p. 199 - 203 (2012/08/08)
An N-salicylidenaniline (SA), compound 1 with 15-crown-5 moiety, was synthesized. The time-dependent NMR was used to track its photochromic process. The experimental results showed that ultraviolet irradiation would lead compound 1 to decompose into the corresponding salicylaldehyde and amine in chloroform solution, instead of experiencing a photochromic process. By the same method, the reported photochromic results of other SAs were also corrected.
Synthesis, metal ion binding, and photochromic properties of benzo- and naphthopyrans annelated by crown ether moieties
Paramonov, Sergey V.,Lokshin, Vladimir,Smolentsev, Artem B.,Glebov, Evgeni M.,Korolev, Valeri V.,Basok, Stepan S.,Lysenko, Konstantin A.,Delbaere, Stéphanie,Fedorova, Olga A.
experimental part, p. 7873 - 7883 (2012/10/08)
Combining a photochromic chromene with a crown ether moiety results in systems in which photochromism and ionophoric properties could significantly influence each other. In this paper, we report the synthesis of several chromenes annelated by 15(18)-crown