Teaching stereoselective carbonyl chemistry to a majors/honors section sophomore organic laboratory

CHED 1555

Cheryl M. Mascarenhas, cmascarenhas@ben.edu, Sarah E. St. John, sarah_st.john@ben.edu, Kiel E. Lazarski, Alan A. Rich, and Erick Pasciak. Department of Chemistry, Benedictine University, 5700 College Road, Lisle, IL 60532
The concepts of stereochemistry and stereoselective reactions are challenging for students to grasp and could be better illustrated if the students were presented with the opportunity to perform stereoselective reactions in the lab, separate and analyze product isomer ratios by HPLC or GC. Unfortunately, there are few experiments in the literature that invoke asymmetric catalysis, primarily because it is difficult to tailor these experiments to the sophomore organic curriculum: they are typically time-consuming, require expensive catalysts and inert atmosphere techniques. Our research has focused on the incorporation of enantioselective organic transformations into a sophomore-organic honors/majors lab course. A requirement for these experiments is that they can be performed easily in a two-week lab sequence, with wet solvents under oxygenated-atmospheres. Two such projects that we have developed are organocatalytic asymmetric aldol and Robinson annulations. The experimental design and planning of these projects, including student assessment information, are presented.