Dab tsi yog tus nqi qhia ntawm e1 cov tshuaj tiv thaiv?
Dab tsi yog tus nqi qhia ntawm e1 cov tshuaj tiv thaiv?

Video: Dab tsi yog tus nqi qhia ntawm e1 cov tshuaj tiv thaiv?

Video: Dab tsi yog tus nqi qhia ntawm e1 cov tshuaj tiv thaiv?
Video: Tshuaj theem vim li cas thiaj tau nqi ?/ Siv kho mob dab tsi?/paris polyphylla use for? 2024, Kaum ib hlis
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E1 qhia a tshem tawm , unimolecular tshuaj tiv thaiv , qhov twg tus nqi = k [R-LG]. Hauv ib E1 cov tshuaj tiv thaiv , cov tus nqi kev txiav txim siab kauj ruam yog qhov poob ntawm pawg tawm mus tsim cov carbocation nruab nrab. Qhov ruaj khov dua qhov carbocation yog, qhov yooj yim dua nws yog tsim, thiab qhov nrawm dua E1 cov tshuaj tiv thaiv yuav yog.

Ib yam li ntawd, koj ua li cas e1 cov tshuaj tiv thaiv?

Ib E1 cov tshuaj tiv thaiv koom nrog deprotonation ntawm hydrogen nyob ze (feem ntau yog ib qho pa roj carbon monoxide, los yog txoj hauj lwm beta) cov carbocation uas ua rau tsim cov khoom alkene. Yuav kom ua tiav qhov no, yuav tsum muaj Lewis puag.

Tsis tas li, qhov sib txawv ntawm e1 thiab e2 cov tshuaj tiv thaiv yog dab tsi? Mechanistically, E2 cov tshuaj tiv thaiv yog concerted (thiab tshwm sim sai dua), whereas E1 cov tshuaj tiv thaiv yog stepwise (thiab tshwm sim qeeb thiab ntawm tus nqi zog dua, feem ntau). Vim E1 os kev coj tus cwj pwm, carbocation rearrangements tuaj yeem tshwm sim hauv nruab nrab, xws li hais tias tus nqi zoo yog hloov chaw ntawm cov pa roj carbon ntau ruaj khov.

Xav txog qhov no, qhov sib npaug ntawm tus nqi e2 yog dab tsi?

E2 qhia ib tshem tawm , bimolecular tshuaj tiv thaiv , qhov twg tus nqi = k [B][R-LG]. Hauv ib E2 cov tshuaj tiv thaiv , cov tshuaj tiv thaiv ua 2sp3 C atoms rau hauv sp2 C atoms. Qhov no txav cov neeg hloov pauv txuas ntxiv kom txo qis kev sib cuam tshuam tsis zoo. Yog li ntau qhov kev hloov pauv ntau dhau los E2 tshem tawm sai dua.

Puas yog e1 cov tshuaj tiv thaiv sib tham?

Yog li ntawd, qhov ruaj khov tshaj qhov carbocation yog, qhov nrawm dua tshuaj tiv thaiv yuav yog. Tus nqi ntawm E2 tshuaj tiv thaiv nyob ntawm ob qho tib si substrate thiab lub hauv paus, txij li tus nqi txiav txim siab theem yog bimolecular ( kev sib tham ). Lub hauv paus muaj zog yog feem ntau yuav tsum tau, ib qho uas yuav tso cai rau kev hloov pauv ntawm pawg polar tawm.

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