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We describe here a 4 hour experimental session based on reaction monitoring of the degradation of an organic pollutant via a Fenton-like reaction. An aqueous solution of p-nitrophenol is treated with hydrogen peroxide and magnetite, and the progress of the reaction is monitored by UV-vis spectrophotometry and/or gas chromatography using an internal standard. During that session, undergraduate students discovered a new scope of heterogeneous catalysis, namely, a green process for water depollution. Behind the simplicity of setting up the Fenton-like reaction, they were challenged by the requirements of replicability and precision of the quantitative tracking of the reaction. They appreciated being confronted with a realistic environmental problem and seeing what role catalysis and modern chemistry could play to tackle the issue.

We adapted a classical asymmetric Michael addition for a 1 day experimental session (6-8 h) for third- or fourth-year undergraduate students. The experiment contains three steps: synthesis of a chiral Lewis acid, LiAl((S)-BINOL)[subscript 2], then its use as a catalyst in the Michael addition of diethyl malonate on cyclopentenone, followed by purification through column chromatography on silica gel. The desired product can be fully characterized by 1D and 2D NMR experiments and IR spectroscopy. The enantiomeric excess can be determined by polarimetry and [superscript 1]H NMR using the chiral lanthanide shift reagent Eu(hfc)[subscript 3]. This laboratory experiment bridges the gap between theoretical courses about asymmetric reactions and practical implementations of enantioselective reactions.