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Fractional distillation is part of the essential experimental techniques taught to first-year chemistry students, especially during practical organic chemistry work. The characterization of the distillate generally involves measuring the boiling temperature, the refractive index or the infrared spectrum. In this paper, an unknown mixture composed of two organic solvents is given to the students in order to be separated by fractional distillation and characterized. To perform this task, the benchtop 1 H NMR spectroscopy was introduced to complement other analytical methods and to familiarize students with this technique while implementing their reasoning abilities.

A phenoxycalix[4]pyrrole-epichlorohydrin based extractant was easily synthesized for the first time and used for iodide and bromide extraction from aqueous media.

A flash purification system using prepacked cartridges containing different silica weight and particle sizes was employed to demonstrate the influence of column characteristics on chromatographic resolution. This chromatographic experiment was a helpful introduction to chromatographic courses where the influence of particle sizes was addressed only theoretically and it allows students to experience the concept in an active learning style experiment. After running a predefined set of experiments to understand concepts, students were asked to design their own experiment to achieve the best chromatographic resolution. Moreover, the difference of mass versus concentration detectors was highlighted using Ultraviolet (UV) and Evaporative Light Scattering Detectors (ELSD). Questionnaires were also used to define the students' initial knowledge and to assess on what they learned following this lab.

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The selective detection and quantification of hydrazine, a hazardous pollutant commonly used in industries, was performed by UV-spectroscopy with a repurposed β-dicyanovinyl substituted calix[4]pyrrole as chemosensor. Selectivity was evaluated in acetonitrile towards various nitrogen-containing compounds and a nucleophilic thiol. Moreover, influence of several parameters (time, water content and temperature) on hydrazine detection of the chemosensor was evaluated. This work allows the sensing of hydrazine with a LOD of 1.3 mg/L and a linear response on the 40-1000 μM range. Naked eye detection was also performed.

Calix[4]pyrrole derivatives are usually used to recognize charged species or polar guests through non-covalent interactions, but the chemodosimetric approach remains scarce in the literature. In this study, the selective chemodosimetric detection and quantification of hydrazine, a hazardous pollutant commonly used in industy, was performed using UV-spectroscopy with a repurposed -dicyanovinyl substituted calix[4]pyrrole sensor. The selectivity of the chemodosimeter towards hydrazine was evaluated in acetonitrile with various nucleophiles (nitrogen-containing compounds and a thiol). In addition, the influence of several parameters (time, water content, and temperature) on hydrazine detection by the sensor was evaluated. This study allows for the sensing of hydrazine with a limit of detection (LOD) of 1.3 mg/L and a linear response in the 10-1000 M range. The ability to detect hydrazine with the naked eye has also been demonstrated. This paper reports one of the first chemodosimetric approach employed with calix[4]pyrrole to detect and quantify a neutral molecule, namely hydrazine.