Synthesis of Chemiluminescent Esters: A Combinatorial Synthesis Experiment for Organic Chemistry Students

In this laboratory exercise a peroxyoxalate chemiluminescence experiment has been integrated with a combinatorial synthesis experiment. Students prepare a number of esters, in reactions between acyl chlorides and phenols, and test them for chemiluminescence. Each student prepares 1-2 esters if the experiment is parallel combinatorial synthesis, or two mixtures of esters if the experiment is split and mix combinatorial synthesis, and tests them for chemiluminescence. Results from the entire class are combined and, based on their results, the students identify general structural features of an active (chemiluminescent) ester. In addition to rubrene, which gave off the most intense light, a number of inexpensive fluorophores are suitable for this experiment including chlorophyll and anthracene. The laboratory exercise is suitable for introductory organic chemistry students and can be modified for more advanced students