Dehydration of Linalool with Two Types of Reagents Based on Silica Gel: Experiment for Distinguishing between Products by Aroma

In primary organic chemistry, students learn about the dehydration of ethanol to ethylene with concentrated sulfuric acid. Similar reactions (the dehydration of alcohols) exist in nature. For example, various alkenes with aromas are synthesized from linalool, a monoterpene tertiary alcohol. In this laboratory experiment, we report experiments suitable for high school students in which linalool is dehydrated with two safe dehydrating agents to obtain mixtures of alkenes with different aromas. The students were asked to perceive the differences in aromas of the products. The results showed that most students perceived the aromas as expected. By completing this experiment and without direct instrumental analysis, students learned that reactions by the same raw material can yield products with different composition ratios depending on the type of dehydrating agent. The synthesis of naturally occurring aroma compounds also stimulated an interest in chemistry.