ORGANIC CHEMISTRY
Dr Nam T. S. Phan Faculty of Chemical Engineering HCMC University of Technology Office: room 211, B2 Building Phone: 8647256 ext. 5681 Email: ptsnam@hcmut.edu.vn
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Chapter 6: CONJUGATED ALKADIENES
A non-polar molecule
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Reactions of isolated dienes are just like those of alkenes
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NOMENCLATURE OF ALKADIENES
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PREPARATION OF 1,3-ALKADIENE Dehydrogenations
Eliminations of unsaturated alcohols & alkyl halides
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ELECTROPHILIC ADDITION REACTIONS
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Reaction mechanism:
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DIELS-ALDER REACTIONS
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Reactivity of the dienophile is increased if 1 or more electron-withdrawing groups are present
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Partial positive charge
Stereochemistry
Racemic mixture
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In order to participate in a Diels-Alder reaction, the diene must be in an s-cis conformation
C1 & C4 are too far apart to react with the dienophile
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Polymerizations
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