Using Trityl Carbocations to Introduce Mechanistic Thinking to German High School Students

Catharina Schmitt¹ and Michael Schween^1,

¹Faculty of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, Marburg, Germany

Cite this paper

Catharina Schmitt and Michael Schween. Using Trityl Carbocations to Introduce Mechanistic Thinking to German High School Students. World Journal of Chemical Education. 2018; 6(1):18-23. doi: 10.12691/WJCE-6-1-4

Abstract

Mechanistic problem-solving is the scientific core competence of organic chemistry. Hence, many students struggle with developing multivariate mechanistic thinking. They very often rely on memorized rules and propose products without providing a detailed mechanistic pathway. They simply apply problem-solving strategies from general chemistry, which is more product-oriented than organic chemistry. A process-oriented view that is highly demanded in organic chemistry requires the understanding and connection of basic principles and concepts. In order to practice the process-oriented approach and introduce advanced German high school students to mechanistic thinking, we developed a set of three new experiments to generate carbocations in model reactions for the observation of reactive intermediates. Trityl cations proved to be the best ones for an experimental investigation of a reaction’s progress which is accessible with a simple analysis that generates explicit results by changes in color and electric conductivity. The experiments are arranged in a guided inquiry workshop of six steps alternating theoretical (oral group discussions) and experimental phases.

Keywords

high school, First-Year Undergraduate, Laboratory Instruction, organic chemistry, problem-solving, carbocations, conductivity, kinetics, Mechanisms of Reactions, reactive intermediates

Copyright

This work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

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