World Journal of Chemical Education
ISSN (Print): 2375-1665 ISSN (Online): 2375-1657 Website: Editor-in-chief: Prof. V. Jagannadham
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World Journal of Chemical Education. 2021, 9(4), 175-184
DOI: 10.12691/wjce-9-4-10
Open AccessSpecial Issue

Photobromination (SR) and Corresp. SN1 Reactions – Key Reactions for the Development and the Application of the Concept of Hyperconjugation

Marc Zimmermann1, Dennis Domke1 and Michael Schween1,

1Fachbereich Chemie, Philipps-Universität, Marburg, Germany

Pub. Date: November 28, 2021
(This article belongs to the Special Issue Photoprocesses in Chemical Education)

Cite this paper:
Marc Zimmermann, Dennis Domke and Michael Schween. Photobromination (SR) and Corresp. SN1 Reactions – Key Reactions for the Development and the Application of the Concept of Hyperconjugation. World Journal of Chemical Education. 2021; 9(4):175-184. doi: 10.12691/wjce-9-4-10


This article first describes photochemical bromination reactions of two different reactants proceeding via electron septet intermediates according to the radical substitution reaction mechanism (SR). The case comparison is intended to enable learners – high school or university first-year organic chemistry students – to work out the concept of hyperconjugation, which is very significant for organic chemistry, by intertwining experimental results and theoretical interpretation (of free radical intermediates) closely. Since students often do not succeed in transferring concepts they have already learned from one mechanism to another, the second step will be to transfer and apply the concept of hyperconjugation to carbenium ions as reactive intermediates by means of an analogous experimental case comparison of first-order nucleophilic substitution reactions (SN1).

hyperconjugation concept development concept transfer and application contrasting cases reaction mechanisms

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