Organic chemistry students' ideas about nucleophiles and electrophiles: the role of charges and mechanisms

Organic chemistry students struggle with reaction mechanisms and the electron-pushing formalism (EPF) used by practicing organic chemists. Faculty have identified an understanding of nucleophiles and electrophiles as one conceptual prerequisite to mastery of the EPF, but little is known about organic chemistry students' knowledge of nucleophiles and electrophiles. This research explored the ideas held by second-semester organic chemistry students about nucleophiles and electrophiles, finding that these students prioritize structure over function, relying primarily on charges to define and identify such species, both in general and in the context of specific chemical reactions. Contrary to faculty who view knowledge of nucleophiles and electrophiles as prerequisite to learning mechanisms and EPF, students demonstrated that they needed to know the mechanism of a reaction before they were able to assess whether the reaction involved nucleophiles and electrophiles or not.

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The Principle of Conservation of Structural Aspect: Facilitating Visual Communication and Learning in Organic Chemistry Instruction

10.26434/chemrxiv.8144075.v1 ◽

2019 ◽

Author(s):

john andraos

Keyword(s):

Organic Chemistry ◽

Chemical Reactions ◽

Reaction Mechanisms ◽

Visual Communication ◽

Structural Aspect ◽

Chemical Bonds ◽

Journal Articles ◽

Chemistry Instruction ◽

Individual Reaction ◽

Training Exercises

<p>An effective pedagogical method is presented for the visual communication of chemical reactions learned in organic chemistry undergraduate courses. The basis for the method is the preservation of the visual aspect of reactant and product structures so that the tracking of cleaved and formed chemical bonds is made self-evident. This consequently leads to improved clarity of presentation and a better understanding and grasp of proposed reaction mechanisms to explain product outcomes. The method is demonstrated for a variety of individual reaction types and synthesis plans. Various visual training exercises are also presented using ChemDraw Ultra 7.0 software and literature table of contents (TOC) graphics appearing in journal articles.</p><br>

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ChemInform Abstract: Specific Chemical Reactions within Self-Assembled Hollow Complexes

ChemInform ◽

10.1002/chin.200946248 ◽

2009 ◽

Vol 40 (46) ◽

Author(s):

Takashi Murase ◽

Makoto Fujita

Keyword(s):

Chemical Reactions ◽

Specific Chemical ◽

Specific Chemical Reactions ◽

Self Assembled

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Organic chemistry students’ challenges with coherence formation between reactions and reaction coordinate diagrams

Chemistry Education Research and Practice ◽

10.1039/c8rp00064f ◽

2018 ◽

Vol 19 (3) ◽

pp. 732-745 ◽

Cited By ~ 15

Author(s):

Maia Popova ◽

Stacey Lowery Bretz

Keyword(s):

Organic Chemistry ◽

Reaction Mechanisms ◽

Reaction Coordinate ◽

Structured Interviews ◽

Chemistry Students ◽

Student Difficulties ◽

Need Support ◽

Elimination Reactions

The purpose of this study was to elucidate and describe students’ thinking when making connections between substitution and elimination reactions and their corresponding reaction coordinate diagrams. Thirty-six students enrolled in organic chemistry II participated in individual, semi-structured interviews. Three major themes were identified that characterize students’ difficulties with integrating the information from the reactions and the reaction coordinate diagrams: incorrect ideas about the meanings of the reaction coordinate diagrams’ features, errors when examining reaction mechanisms, and an inability to assess the relative energies of reaction species. These findings suggest that students need support for coherence formation between reactions and reaction coordinate diagrams. Implications for teaching to address these student difficulties are suggested.

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