World Journal of Chemical Education
ISSN (Print): 2375-1665 ISSN (Online): 2375-1657 Website: http://www.sciepub.com/journal/wjce Editor-in-chief: Prof. V. Jagannadham
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World Journal of Chemical Education. 2018, 6(1), 18-23
DOI: 10.12691/wjce-6-1-4
Open AccessSpecial Issue

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

Catharina Schmitt1 and Michael Schween1,

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

Pub. Date: January 27, 2018

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

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