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Solution Effects on Cesium Complexation with Calixarene - Crown Ethers from Liquid to Supercritical Fluids

Description: Supercritical fluid CO2 is an alternative solvent for extraction of metals. The solubility parameter of supercritical CO2 varies with density resembling that of liquid hexane at moderate pressures in the supercritical region to those of chlorinated solvents at very high pressures. By changing density of supercritical CO2, the solvation environment of a metal chelate system can vary continuously and resembles over a wide range of solvents. Thus, supercritical CO2 provides a unique system for studying solvation effects on metal chelation. This project is designed to investigate the solvation effects on cesium complexation with macrocyclic compounds including crown ethers and calixarene-crown ethers in CO2 from liquid to supercritical region at high pressures. A powerful spectroscopic technique for studying cesium chelation is nuclear magnetic resonance (NMR). Cesium has only one isotope, 133Cs, with a nuclear spin I = 7/2. Popov et al. used NMR to study cesium complexation with crown ethers and cryptand.
Date: June 1, 1999
Creator: Wai, Chien M. & Yonker, Clem
Partner: UNT Libraries Government Documents Department

Synthesis of Compounds for Los Alamos National Laboratory

Description: As part of contract 6709U0015-3C, the compounds listed were synthesized and transferred to LANL for evaluation. Work on these has resulted in several papers, manuscripts and talks bearing LANL and UTD co-authorship. The detailed synthetic procedures are described and the chemical structure of the mentioned compounds are shown in a table. Synthetic procedures: (1) 2-Methoxy-5-(2{prime}-ethyl hexyloxy)-1,4-distyrylbenzene--see synthesis of compound V in the reference [1]. (2) MEHPPV : 1.000 g 1,4-methoxyethylhexyloxy-2,5-dibromomethylbenzene + 0.0042 g (1 mol %) anthracene were dissolved in 35 ml dry THF and 1.0 M solution of t-BuOK in THF was added slowly during 60 min and stirred at room temperature for 20 hours. The red suspension was precipitated in 200 ml cold MeOH, the solid was filtered, washed by MeOH and dried in vacuum. The red-orange solid was extracted by boiling hexane for 24 hours. Insoluble in hexane red polymer was extracted by boiling xylene for 24 hours, soluble in xylene fraction was dissolved in THF and precipitated in MeOH. After filtration and drying in vacuum 0.220 g(36% yield) of red polymer with M{sub W}=357000 and absorption maximum at 496 nm (chloroform) was obtained. (3)1,4-distyrylbenzene - see synthesis of compound 1 in the reference [1]. (4)1,4-Bis-(2{prime},5{prime}-dimethoxystyryl)-2-methoxy-5-(2{prime}-ethylhexyloxy)benzene: This compound was obtained in 51% yield according the general procedure for the Wittig reaction described in the reference [1] from 2- methoxy-5(2{prime}-ethylhexyloxy)-1,4-xylylene-bis(triphenylphosphonium chloride) and 2,5-dimethoxybenzaldehyde, m.p.49-51 C. (5) Films of aromatic copolyamides with fragments of 9,10-bis(p-carboxyphenyl) anthracene and bis(m-aminophenyl)-9,10-anthracene--see synthesis of copolyamides XXI and XXII in the reference [2]. (6,7) Films of the solid solution of 9,10-diphenylanthracene in poly(m- phenyleneisophtalamide) (PMPI) were obtained from the 5.0% solution of mixture 0.231 g PMPI and 0.0319 g 9.10-diphenylanthracene in N-MP at conditions described in the reference [2]. (8) 2,5-Didodecyloxy-1,4-distyrylbenzene--see synthesis of compound IV in the reference [1]. (9) 2,5- Dioctyloxy-1,4-distyrylbenzene--see synthesis of ...
Date: July 20, 1999
Creator: Ferraris, J.P.
Partner: UNT Libraries Government Documents Department