AZO-CROWN ETHERS. THE DYES WITH AZO GROUP DIRECTLY INVOLVED IN THE CROWN ETHER SKELETON
作者:Masanobu Shiga、Makoto Takagi、Keihei Ueno
DOI:10.1246/cl.1980.1021
日期:1980.8.5
Crown-type polyether azo dyes 1∼3 were synthesized, and the ion-pair extraction of sodium and potassium ion was studied. The extraction behavior resembles those of benzo-type crown ethers, but changes on light illumination due to trans–cis isomerization of the dyes. The cis-form lacks the affinity to metal ions.
Newcrownethers which have a benzeneazo group as a building block of a macrocyclic polyether ring. The complexation properties of these new azobenzo-crown ethers with alkali and alkalineearthmetal iodide salts were investigated in acetonitrile solution spectrophotometrically. The complex formation constants were evaluated for alkali metal salts. The azo group is not particularly a favorable component
Luboch; Biedrzycka, Polish Journal of Chemistry, 2003, vol. 77, # 1, p. 47 - 51
作者:Luboch、Biedrzycka
DOI:——
日期:——
Rearrangement of azoxybenzocrowns into chromophoric hydroxyazobenzocrowns and the use of hydroxyazobenzocrowns for the synthesis of ionophoric biscrown compounds
The Wallach rearrangement was used as a method for preparing p-hydroxyazobenzocrown ethers starting from different azoxybenzocrowns as substrates. Synthesis of a series of p-hydroxyazobenzocrowns under modified conditions and characterization of the obtained products are presented. o-Hydroxyazobenzocrowns were identified among the products of the photochemical rearrangement of azoxybenzocrowns. Novel biscrowns were synthesized from p-hydroxyazobenzocrown ethers. The synthesized host molecules, differing in the size of the macrocycles and in the substituents in the aromatic rings, have the same dioxymethylene linkers. They were used as potential sodium or potassium ionophores in classic and miniature (screen-printed) ion-selective electrodes. The properties (tautomerism, acid base equilibrium) of newly prepared o-hydroxyazobenzocrown ethers and their p-substituted analogs were studied using spectroscopic methods and compared. (C) 2013 Elsevier Ltd. All rights reserved.