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A chiral stationary phase with an immobilized, optically active diamine was prepared for the separation of enantiomers. The synthesis of the phase was carried out by bonding (–)trans-1,2-cyclohexanediamine to microparticulate silica gel through the coupling agent 3-glycidoxypropylsilane. The resolution of the racemic compounds catechin, 2,2-dihydroxy-1,1binaphthyl and trans-1,2-cyclohexandiol, is reporte

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The thermal properties of some complexes of copper(l I) with pyridine-2-atdoxime (HPAO), where the ligand appears either as the ion (PAO-) or as a neutral molecule, were determined in vacuo and in dynamic nitrogen and oxygen gas atmospheres. The study was carried out by thermoanalytical (TG, DTG. DTA), spectroscopic and spectrometric (UVvisible, IR, diffuse reflectance, mass) techniques.The initial decomposition temperature is influenced by the number of acid hydrogens in the complex; the thermal stability sequence in vacuo is:The thermal decomposition reactions occur in several separate steps, the first of which gives rise to partial ligand decomposition, the reduction of copper(ll) to copper(I), and the conversion of the residual pyridine-2-aldoxime into acid amide.Several papers have been published on the complexes of metal ions with pyridine-2--aldoxime (CsH6N20; HPAO). Some copper(l I) complexes with this ligand have been studied in aqueous solution, or precipitated and characterized using IR, diffuse reflectance, polarographic and potentiometric techniques [1][2][3][4][5][6][7], but no data have been reported on the thermal stabilities and decomposition reactions.Following thermoanalytical studies of the complexes of 3 d metal ions with organic ligands [8][9][10][11], in this paper we report results on the thermal behaviour of the complexes [Cu(C6H5N20)2Hn]CI n (where n = 0, 1 or 2). The study has been carried out by thermogravimetry, differential thermal analysis and mass spectrometry; the proposed decomposition mechanisms are supported by analysis of the stable intermediates obtained by interruption of the heating of the samples at the appropriate temperatures. Experimenta I ApparatusThe thermal measurements were carried out by means of a Perkin-Elmer TGS-2 thermal analyser and DTA 1700. TG runs were made in vacuo and in dynamic nitrogen

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