CHEM 2301 Lecture 38: Diels-alder 11 & 12 (4/23)
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"stereochemical requirement of diels-alder!
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"s-cis diene!
"e- withdrawing groups (C=O on dienophile!
"""" C=N) !
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"cis dienophile —> cis sub. product !
"trans dienophile —> trans sub. product !
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"diene!!!!!!!!cis (meso)"
!!!dienophile (cis s)"
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!!!dienophile (trans) !!!trans + Enantiomer (racemic) "
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!!!!!!!!cis (meso) "
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!!!!!!!!trans (racemic)"
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endo rule!
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"when endo + exo products are possible, endo products favored !
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"""""(H atoms omitted for clarity diene)!
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" " " " " " " " " " " " """""""""""""""""""""""""""phases match (symmetry allowed)"
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" diene! dienophile !!!!dienophile !
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