Qhov Tseem Ceeb Qhov txawv - Staggered vs Eclipsed Conformation
Ob nqe lus, Staggered thiab eclipsed conformation (ob ceg tseem ceeb ntawm Newmann projections) yog siv hauv Organic Chemistry los piav qhia txog kev npaj ntawm atoms hauv qee cov organic molecules. Nyob rau hauv cov nqe lus ntawm stability, staggered conformation yog ruaj khov dua eclipsed tsim. Qhov tsim ntawm staggered kev pom zoo yog qhov zoo dua vim nws lub zog conformational tsawg kawg nkaus. Qhov no yog qhov sib txawv tseem ceeb ntawm staggered thiab eclipsed conformation.
Txoj kev sib haum xeeb yog dab tsi?
Staggered conformation is a chemical conformation of ethane-like molecule (CH3-CH3=abcX–Ydef) uas cov hloov pauv a, b, thiab c yog txuas ntawm qhov siab tshaj plaws ntawm d, e, thiab f. Nyob rau hauv cov ntaub ntawv no, lub torsion lub kaum sab xis yog 60 ° thiab lub conformational zog yog yam tsawg kawg nkaus. Qhov kev xav tau tseem ceeb rau qhov kev lees paub no yog qhib cov saw hlau ib qho tshuaj tiv thaiv kom txuas ob sp 3 hybridisedatoms. Qee cov molecules xws li n -butane tuaj yeem muaj cov qauv tshwj xeeb ntawm cov lus pom zoo: gauche thiab anti.
Dab tsi yog Eclipsed Conformation?
Eclipsed conformation tuaj yeem muaj nyob hauv txhua txoj saw qhib thaum ib daim ntawv cog lus txuas ob sp3hybridized atoms. Hauv qhov no, ob qhov hloov pauv (cia peb hais -X thiab -Y) ntawm cov atoms uas nyob ib sab (hais A thiab B) nyob ze tshaj plaws. Nyob rau hauv lwm yam lus, lub torsion lub kaum sab xis X-A-B-Y yog 0 ° nyob rau hauv lub molecule. Qhov kev lees paub no muaj lub zog siab tshaj plaws vim muaj kev cuam tshuam tsis zoo.
Qhov txawv ntawm Staggered thiab Eclipsed Conformation yog dab tsi?
qauv:
Staggered Confirmation: Staggered kev pom zoo tuaj yeem nkag siab zoo tshaj plaws los ntawm kev siv ethane molecule. Thaum peb saib los ntawm sab, nws qhov kev pom zoo staggered tuaj yeem piav qhia raws li hauv qab no.
Eclipsed Conformation: Ethane molecule tuaj yeem coj los ua ib qho piv txwv yooj yim tshaj plaws kom nkag siab txog kev ua raws li eclipsed. Thaum peb saib los ntawm sab, cov eclipsed conformation ntawm ethane molecule tuaj yeem pom raws li hauv qab no.
Kev ruaj ntseg:
Staggered Confirmation: Staggered kev pom zoo tuaj yeem suav hais tias yog qhov kev sib haum xeeb tshaj plaws vim nws tau txo qis hauv cov molecule. Vim tias cov khoom sib txuas hauv cov molecule muaj ntau qhov sib npaug sib npaug thiab qhov no txo qhov kev tawm tsam ntawm cov pa roj carbon monoxide pem hauv ntej thiab cov pa roj carbon rov qab. Tsis tas li ntawd, lub staggered conformation yog stabilized los ntawm lub hyperconjugation.
Eclipsed Conformation: Lub eclipsed conformation yog tsis tshua muaj dej siab vim hais tias nws muaj peev xwm muaj kev sib cuam tshuam ntau dua ntawm lub hauv ntej thiab nram qab substituents; qhov no ua rau muaj kev nyuaj siab ntxiv. Lub kaum sab xis ntawm sab xub ntiag thiab sab nraub qaum tuaj yeem yog dab tsi.
Muaj Peev Xwm Zog:
Daim duab ntawm lub zog muaj peev xwm hloov pauv raws li kev ua haujlwm ntawm lub kaum sab xis dihedral (dihedral lub kaum sab xis ntawm ob lub hydrogens ntawm cov pa roj carbon sib txawv) qhia lub zog sib txawv ntawm qhov kev lees paub staggered thiab eclipsed kev pom zoo.
Staggered Confirmation:
Cov phiaj xwm saum toj no qhia tau tias qhov kev sib haum xeeb staggered muaj qhov tsawg kawg nkaus lub zog. Qhov no txhais tau tias qhov no yog daim ntawv ruaj khov tshaj plaws thiab nws tuaj yeem yog daim ntawv pom zoo tshaj plaws ntawm lwm qhov kev lees paub.
Eclipsed Conformation:
Raws li cov duab saum toj no, eclipsed kev pom zoo muaj lub zog siab tshaj plaws. Qhov no txhais tau hais tias kev hloov pauv hloov pauv yog lub xeev hloov pauv thiab nws yeej tsis muaj nyob hauv daim ntawv no.
Definition:
Conformations:
Kev sib haum xeeb yog cov haujlwm sib txawv uas cov molecule tuaj yeem ua thaum khaws cov atoms thiab cov ntawv cog lus ntawm cov molecule. Hauv qhov no, qhov kev hloov pauv nkaus xwb yog cov ces kaum uas qee qhov ntawm cov molecule tau khoov lossis twisted.
Torsion angle (dihedral angle):
Nws xa mus rau lub kaum sab xis ntawm dav hlau los ntawm ob pawg ntawm peb atoms, muaj ob lub atoms sib xws. Hauv lwm lo lus, nws yog lub kaum sab xis ntawm ob lub dav hlau sib tshuam.
