The catalytic properties of three copper complexes, [Cu()](ClO) (), [Cu()](ClO), () and [Cu()](ClO) () (where = ethylenediamine, amp = 2-aminomethylpyridine and = 2,2'-bipyridine), were explored upon the oxidation of benzyl alcohol (BnOH). Maximized conversions of the substrates to their respective products were obtained using a multivariate analysis approach, a powerful tool that allowed multiple variables to be optimized simultaneously, thus creating a more economical, fast and effective technique. Considering the studies in a fluid solution (homogeneous), all complexes strongly depended on the amount of the oxidizing agent (HO), followed by the catalyst load.
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February 2024
The present work describes the development of a headspace solid-phase microextraction (HS-SPME) followed by gas chromatography - mass spectrometry (GC-MS) method for the qualitative analysis of compounds in seized ecstasy tablets that can be easily implemented in regular laboratories. HS-SPME with a DVB/CAR/PDMS 50/30 µm fiber was used to extract the ecstasy pills' components, including major and minor ones, in a single extraction/chromatographic run. For HS-SPME, the incubation time (0 min to 30 min), the extraction time (10 min to 40 min) and temperature (40 °C to 80 ºC), the buffer volume (3 mL to 8 mL), the buffer pH (6 to 9) and the NaCl concentration (0 mol/L to 6 mol/L) were evaluated using fractional factorial design.
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