NMR Kinetics of the Diels-Alder Reactions of 9-Substituted Anthracenes: Development of an Organic Chemistry Lab Experience
Date of Award
Restricted Access Thesis
College of Theology, Arts, & Sciences
Math & Science
Andrew T. Johnson
Chemistry education has come a long way for its early beginnings. The study of chemistry is constantly changing and evolving as molecules are constantly moving and evolving (Lagowski, 1998). It is universally accepted that organic chemistry is one of the most difficult classes students will ever take at the undergraduate level. Learning/teaching NMR spectroscopy in particular is no easy task. Solving an unknown spectrum utilizes both conceptual understanding and problem solving skills leaving no direct path to follow (Angawi, 2014, p. 823). Consequently, teaching these sets of skills in the course can create a very positive experience for the students in promoting an active learning environment (Cramer, 2013, p. 57) as well as giving them the opportunity to work on an advanced instrument used in many high-tech labs (Dávila, et al., 2002, p. 997).
In designing a laboratory experiment for undergraduate students, the kinetics of the Diels-Alder reaction using maleic anhydride with anthracene and its derivatives (9-methylanthracene and 9-anthracenecarboxaldehyde) was the main focus. Substituent effects on the reactions rates have been studied based on their electron-withdrawing and electron-donating natures (Sustmann, et al., 1972). This experiment allowed for successful observation of the effect that modifications can have on the kinetics of the reaction. The addition of the methyl group to anthracene was observed to have significantly increased the speed of the reaction compared to the reaction without the methyl group. With the use of proton NMR spectroscopy to study the kinetics of varying Diels-Alder reactions, students will be able to utilize skills taught in the classroom and build on these experiences necessary for a future career in science.