CHEM 2301 Lecture Notes - Lecture 35: Molecular Orbital Theory, Allyl Group, Halogenation
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"chap 11 conjugation in Alkadiene & allylic systems
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"—> P orbitals can overlap 3 or more adjacent atoms !
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Double bonds associated by just 1 single bond!
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"allylic carbocation """ " " " 1,3-diene!
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"11.1 allyl group " !
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"""""""""resonance stabilize !
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"""""" more stable (major) !
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"stability of carbocation !
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"methyl < 1 < 2 = 1 allylic < 3 = 2 allylic < 3 allylic !
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"another bonding picture: molecular orbital (MO) theory !
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""""""3 p orbitals ] 3 MO (come from p orbitals)!
""""""2 e- in bonds!
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"""""""lowest unoccupied " " """"""highest occupied molecular !
"""""""molecular orbitals, (lumo)" """"""orbital (homo)"!
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"11.2 SN1 & SN2 rxns of allylic halides!
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"SN1 = carbocation intermediate !
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""⬆carbocation stability " " ⬇Ea"" ⬆rxn rate!
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"A!
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"B!
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