Qhov nruab nrab twg yog tsim los ntawm br2 rau alkene?
Qhov nruab nrab twg yog tsim los ntawm br2 rau alkene?

Video: Qhov nruab nrab twg yog tsim los ntawm br2 rau alkene?

Video: Qhov nruab nrab twg yog tsim los ntawm br2 rau alkene?
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Description: Kev kho mob ntawm alkenes nrog bromine ( Br2 ) muab vicinal dibromides (1, 2-dibromides). Lus Cim: Cov bromines ntxiv rau lub ntsej muag ntawm ob daim ntawv cog lus ( anti ntxiv ”). Qee lub sij hawm cov kuab tshuaj tau hais hauv cov tshuaj tiv thaiv no - ib qho hnyav hnyav yog carbon tetrachloride (CCl4).

Yog li ntawd, dab tsi intermediates koom nrog hauv bromination ntawm alkene?

Kev tshwm sim Txheej txheem cej luam : Cov tshuaj tiv thaiv alkene halogenation, tshwj xeeb tshaj yog bromination lossis chlorination, yog ib qho uas dihalide xws li Cl2 lossis Br2 tau ntxiv rau cov molecule tom qab rhuav tshem cov pa roj carbon monoxide ob daim ntawv cog lus. Cov halides ntxiv rau cov carbons nyob sib ze los ntawm lub ntsej muag ntawm cov molecule.

Ib yam li ntawd, uas alkene yuav muab meso daim ntawv nrog br2? 1 Teb. Ernest Z. trans-Hex-3-ene daim ntawv a meso sib thaum nws reacts nrog bromine . Lub bromination ntawm ib alkene Kev koom tes nrog kev tsim ntawm ib qho nruab nrab cyclic bromonium ion, ua raws li kev tiv thaiv ntxiv ntawm ib qho bromide ion ua daim ntawv cov khoom.

Tsis tas li ntawd, yuav ua li cas thaum br2 reacts nrog alkene?

Alkenes teb hauv qhov txias nrog cov kua ntshiab bromine , los yog nrog ib tug daws ntawm bromine nyob rau hauv cov organic hnyav xws li tetrachloromethane. Ob daim ntawv cog lus tawg, thiab a bromine atom ua txuas rau txhua cov pa roj carbon. Cov bromine poob nws cov xim liab-xim av kom muab cov kua tsis muaj xim.

Dab tsi yog thawj qhov nruab nrab hauv bromination ntawm alkene?

Cov tshuaj tiv thaiv mechanism rau ib alkene bromination tuaj yeem piav raws li hauv qab no. Hauv ua ntej kauj ruam ntawm cov tshuaj tiv thaiv, ib tug bromine molecule mus rau electron nplua nuj alkene carbon-carbon ob daim ntawv cog lus.

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