Exploring the wittig reaction: A collaborative guided-inquiry experiment for the organic chemistry laboratory

James A. MacKay, Elizabethtown College
Nicholas R. Wetzel, Elizabethtown College


A two-week guided-inquiry Wittig reaction experiment was developed for the undergraduate organic laboratory. In week one, groups are assigned a research topic to investigate the Wittig reaction, such as the effect that substituents on the carbonyl compound may have on E/Z selectivity. A hypothesis, controlled by a provided chemical list, is developed along with a series of experiments to test predictions. For example, more Z isomer might be expected from a steric effect of methyl substituents on o-, m-, and p-tolualdehydes. In the second week, students perform reactions by adapting a general procedure and obtain E/Z selectivities from H NMR. Compiled data are shared online as groups aim to support or refute their hypotheses. As a result of the experiment, students gain insights into the nature of science and the analysis of data as well as a better understanding of the research process. © 2014 The American Chemical Society and Division of Chemical Education, Inc. 1