Nws feem ntau cuam tshuam nrog kev sib cuam tshuam ntawm cov hluav taws xob hauv lub sigma orbital nrog ze ze uas tsis yog-bonding p lossis antibonding σ∗ lossis π∗ orbitalstxhawm rau muab txuas ntxiv molecular orbitals uas ntxiv dag zog ntxiv. ntawm qhov system.
Yuav ua li cas ntawm cov orbitals hauv qab no koom nrog kev sib txuas lus?
Hyperconjugation suav nrog delocalization ntawm σ thiab π-bond orbitals, i.e, nws undrgoes σ-π conjugation. Hom delocalization cuam tshuam nrog sigma daim ntawv cog lus orbital yog hu ua hyperconjugation.
Puas hyperconjugation koom nrog delocalisation ntawm pi electrons?
Hyperconjugation yog the delocalisation ntawm sigma electron tseem hu ua sigma-pi conjugation. Kev tshwm sim ntawm α-H nrog rau ob daim ntawv cog lus, triple daim ntawv cog lus lossis cov pa roj carbon uas muaj cov nqi zoo (hauv carbonium ion) lossis umpaired electron (hauv dawb radical) yog ib qho mob rau hyperconjugation.
Yuav ua li cas hauv hyperconjugation?
Lub delocalization ntawm σ-electrons lossis ib khub ntawm electrons rau hauv π-orbital lossis p-orbital yog hu ua hyperconjugation. Nws tshwm sim vim overlapping ntawm σ-bonding orbital lossis lub orbital uas muaj ib leeg ib khub nrog nyob ib sab π-orbital lossis p-orbital. Nws tseem hu ua "tsis muaj daim ntawv cog lus" lossis "Baker-Nathan effect".
Thaum twg qhov tsis zoo Hyperconjugation tshwm sim?
Negative hyperconjugation tshwm sim thaum puv π lossis p orbitals cuam tshuam nrognyob ib sab antibonding σ orbitals(sib piv nrog "zoo" hyperconjugation raws li pom hauv ethyl carbocation). Ib qho piv txwv ntawm cov nyhuv no tuaj yeem pom hauv trifluoromethoxy anion thiab hauv cov nyhuv anomeric.
