The Salix Project: An Integrated, Natural Products-Based “Trans Curriculum” Chemistry Module

The objective of this pilot project was to emphasize fundamental concepts of chemistry in three different courses using a common, natural product-based approach in such a way as to make the process fun, visual, active, and experiential. By using such a natural product-based vehicle it was felt that this would lead to an increase in comprehension and retention of these fundamental concepts. The three courses involved were: Fundamentals of Organic Chemistry (a survey course), General Chemistry, and Organic Chemistry. Willow was chosen not only because it is the basis of the most successful drug in history (aspirin) but also because it is abundant, culturally relevant, (without being proprietary), and with ample amount of history to augment the classes (context). The Fundamentals of Organic Chemistry class was responsible for collecting, extracting and identifying active constituents in the bark, i. e. salicin, a glucoside of salyl alcohol (extraction chemistry, ester chemistry, thin layer chromatography). The Organic Chemistry class was then responsible for the isolating the salicin (column chromatography). Then the General Chemistry class hydrolyzed salicin to salyl alcohol by both chemical and enzymatic means (reaction rates/activation energies). The salyl alcohol was then oxidized to salicylic acid and purified by Organic Chemistry class (aromatic oxidation and recrystallization). Finally, the salicylic acid was esterified to acetyl salicylic acid (aspirin) by the Fundamentals of Organic Chemistry class with the upper Organic class students as tutors.  At the end of the five-week pilot project all three classes, convened to evaluate the project and suggest improvements.