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2005
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April
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In the Laboratory
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Diels–Alder Cycloadditions: A MORE Experiment in the Organic Laboratory Including A Diene Identification Exercise Involving NMR Spectroscopy and Molecular Modeling
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Roosevelt Shaw, Ashika Severin, Miguel Balfour, and Columbus Nettles
Department of Chemistry, Morgan State University, Baltimore, MD 21251
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April 2005
Vol. 82 No. 4
p. 625
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| Abstract |
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The MORE (microwave-induced organic reaction enhancement) technique has been used successfully to prepare two Diels–Alder [π2 + π4] cycloaddition adducts, racemic exo, endo-2,3-dibenzoylbicyclo[2.2.1]hept-5-ene and racemic exo, endo-2,3-dibenzoylbicyclo[2.2.2]octa-5-ene, in high purity and good yields. Microwave synthesis of these two dienes serves as an excellent organic laboratory experiment to demonstrate the rate enhancement advantage of using microwave heating over conventional heating in preparing selected Diels–Alder cycloaddition products. When the splitting patterns of vinyl protons in the NMR spectra of these compounds are used in conjunction with molecular modeling, a pedagogically sound exercise of diene identification emerges from this MORE experiment.
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| Supplement |
A handout for the students, including instructions to obtain the potential energy diagrams, and notes for the instructor, including answers to the postlab questions, are available.
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 Contents |
JCE2005p0625W.doc (Microsoft Word)
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| Download |
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| More Information |
Citation |
Shaw, Roosevelt; Severin, Ashika; Balfour, Miguel; Nettles, Columbus. J. Chem. Educ. 2005 82 625.
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Keywords |
Microwave Diels-Alder Cycloadditions*; Molecular Modeling / Dynamics; NMR Spectrometry; Organic Chemistry
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History |
Created:
Last Updated: |
March 4, 2005
March 14, 2005
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| Home > JCE Print > Journal of Chemical Education > Issues >
2005
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April
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625
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