Intrusive Learning Accompanying Knowledge Transfer During Organic Chemistry Laboratory Experiment: Synthesis, Characterization, and Photoisomerization of α-Cyanostilbenes

Discussion-based outcomes of organic chemistry laboratory experiments form a powerful tool to create a learning environment, facilitate teamwork, and build scientific skills and analytical ability for undergraduate science students. A Knoevenagel-type condensation reaction was selected to demonstrate these results by taking phenylacetonitrile and four different aldehydes as reactants to form α-cyanostilbenes. The reactions were performed under almost neat conditions open to air at room temperature. The short duration (2–20 min) and visual solid product formation also make the experiment attractive. Melting points, TLC, FTIR, UV–vis, and GC–MS were utilized to characterize and check the purity of the products. Photoisomerization studies were performed in sunlight. Substituent effects in the IR stretching frequency, UV–vis spectra, and photoisomerization behavior create a platform for group discussion and knowledge transfer.