HBr thiab peroxide yog dab tsi?
HBr thiab peroxide yog dab tsi?

Video: HBr thiab peroxide yog dab tsi?

Video: HBr thiab peroxide yog dab tsi?
Video: All the hidden features in Skoda Octavia A5 - скрытые функции skoda octavia 2024, Kaum ib hlis
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Qhov no yog hu ua Markovnikov's Rule. Vim lub HBr ntxiv rau ntawm "txoj kev tsis ncaj ncees lawm" nyob rau hauv lub xub ntiag ntawm organic peroxides , qhov no feem ntau hu ua tus peroxide nyhuv los yog anti-Markovnikov ntxiv. Hauv qhov tsis muaj peroxides , hydrogen bromide ntxiv rau propene ntawm anelectrophilic ntxiv mechanism.

Tsis tas li ntawd, piv txwv li, cov nyhuv peroxide yog dab tsi?

Cov nyhuv peroxide : Kev hloov pauv hauv regioselectivity ntawm qhov sib ntxiv ntawm HBr rau alkene lossis alkyne nyob rau hauv muaj peroxide . Yog tsis muaj a peroxide , HBr ntxiv topropene los ntawm ib qho ionic mechanism (nrog rau carbocation intermediate) togive 2-bromopropane.

Ib yam li ntawd, Peroxide ua dab tsi hauv cov tshuaj tiv thaiv organic? Cov tshuaj tiv thaiv tshwm sim ntawm chav tsev kub nyob rau hauv lub xub ntiag ntawm organic peroxides lossis qee cov pa oxygen los ntawm huab cua. Alkenes teb qeeb heev nrog oxygen los tsim cov kab mob organic peroxides - yog li ob qhov ua tau yog sib npaug rau ib leeg.

Ntxiv mus, yuav ua li cas thaum propene kho nrog HBr?

Electrophilic ntxiv tshwm sim nyob rau hauv uas lub doublebond ntawm propene Nws yuav tawm tsam cov electron-deficient H atom. Lub ib leeg ntawm electrons ntawm bromide ion tawm tsam qhov zoo-them qhov chaw carbon atom, tsim C-Brbond.

HBr ua dab tsi rau alkene?

HBr Ntxiv rau ib Alkene . HBr addsto alkenes los tsim alkyl halides. Ib txoj hauv kev zoo los xav txog cov tshuaj tiv thaiv yog tias pi daim ntawv cog lus ntawm tus alkene ua raws li txaus nucleophile thiab reacts nrog electrophilic proton ntawm HBr . Nyob rau hauv unsymmetrical alkenes , qhov ruaj khov dua ntawm ob qhov ua tau carbocations yuav tsim feem ntau.

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