RESUMO
The present work describes the catalytic activity of Cu-MOF for the one-pot synthesis of tacrine derivatives via a four-component reaction of 2-hydroxynaphthalene-1,4-dione, aldehydes, malononitrile and cycloketones in the presence of AlCl3. The structure of the synthesized compound is confirmed by 1H NMR, 13C NMR, IR, and MASS. The catalyst prepared under pressure is characterized by powder X-ray diffraction and SEM. The noteworthy advantages of this procedure include its broad substrate scope, high yields up to 93%, atom economy, using readily available starting materials and a powerful recyclable nano catalyst. Additionally, there is no need to use column chromatography for purifying products so, it has the potential for large-scale applications in pharmaceutical industries. Another advantage of this method is the ability to recycle the catalyst up to 3 times and reuse it.
RESUMO
This work aims to evaluate for the enantiomeric separations of three agrochemical toxins: haloxyfop-methyl, fenoxaprop-p-ethyl and indoxacarb on crystalline degradation products-chiral stationary phase (CDP-CSP) of high-performance liquid chromatography (HPLC) under normal and polar organic phases. In the normal phase, the mobile phase was n-hexane with alcohols including methanol and isopropanol as polar modifiers. In the polar organic phase mode, the mobile phase was methanol with different percentages of triethylammunium acetate. The influence of flow rate (0.3-0.9 mL/min), analyte concentration and silica gel particle sizes (10, 15 and 30 microm) was investigated. This new chiral stationary phase showed excellent stereoselectivity for the two enantiomers of haloxyfop-methyl and fenoxaprop-p-ethyl and chiral recognition for indoxacarb under normal-phase mode. However, under polar organic phase, only indoxacarb was separated (alpha < 1.5). The chromatographic results were compared with commercial chiral columns.