Cinnamon Oil: An Alternate and Inexpensive Resource for Green Chemistry Experiments in Organic Chemistry Laboratory

We report a series of experiments based upon cinnamon oil that were developed to provide a practical integration of green and sustainable chemistry concepts for the organic chemistry laboratory. Five experiments centering around cinnamaldehyde as a green, plant-based chemical were performed by undergraduate students in a second-year organic chemistry class. Cinnamon oil was obtained through hydro-distillation, and cinnamaldehyde was used to demonstrate the use of a secondary metabolite in chemistry laboratories. Subsequently, a reduction reaction, aldol reaction, and Schiff base formation were carried out. Through these experiments, students are able to practice techniques such as thin-layer chromatography, column chromatography, recrystallization, and measurement of melting points along with UV, FTIR, and H-1 NMR spectroscopy. Microscale practices were employed in each of the reactions, and microscale column chromatography was used for purifications. The final experiment was an antimicrobial activity assessment of cinnamon oil and the cinnamaldehyde derivatives obtained from the previous experiments. Along with an interdisciplinary component, students were exposed to sunscreen chemistry and were led to consider the many uses of each product obtained. These experiments were based upon a single, inexpensive plant metabolite and biobased material to educate students about green chemistry and its practical applications in the undergraduate laboratory.