Qhov sib txawv tseem ceeb ntawm kev hloov pauv dawb radical thiab cov dawb radical ntxiv yog qhov hloov pauv dawb radical cuam tshuam nrog kev hloov ntawm pawg ua haujlwm nrog lwm pab pawg ua haujlwm, thaum dawb radical ntxiv koom nrog kev sib ntxiv ntawm pab pawg ua haujlwm tshiab rau lub molecule.
Ib qho dawb radical tuaj yeem yog atom, molecule, lossis ion uas muaj cov khoom siv hluav taws xob tsis sib xws. Muaj ob yam loj ntawm cov tshuaj tiv thaiv radical: dawb radical hloov thiab dawb radical ntxiv cov tshuaj tiv thaiv.
Dab tsi yog Free Radical?
Ib qho dawb radical tuaj yeem yog atom, molecule, lossis ion uas muaj cov khoom siv hluav taws xob tsis sib xws. Feem ntau, cov khoom siv hluav taws xob tsis sib xws tuaj yeem ua rau cov dawb radicals ua rau muaj tshuaj lom neeg; Txawm li cas los xij, tuaj yeem muaj qee qhov kev zam. Vim lawv cov reactivity siab, feem ntau ntawm cov dawb radicals yuav dimerize spontaneously. Yog li ntawd, lawv muaj lub neej luv heev.
Dab tsi yog qhov hloov pauv dawb radical?
Dawb radical hloov pauv yog hom kev hloov pauv uas cuam tshuam nrog cov dawb radicals raws li qhov cuam tshuam nruab nrab. Reactive intermediates yog luv luv, siab zog, thiab siab reactive molecules. Cov molecules tsim thaum lub sij hawm cov tshuaj tiv thaiv uas zoo li hloov mus rau hauv cov molecules ruaj khov dua. Ntxiv mus, kev hloov pauv cov tshuaj tiv thaiv yog ib hom tshuaj tiv thaiv uas ib pab pawg ua haujlwm hauv cov tshuaj lom neeg yuav raug hloov los ntawm lwm pab pawg ua haujlwm.
Daim duab 01: Cov kauj ruam sib txawv hauv cov kev tawm tsam dawb radical
Daim duab saum toj no qhia txog cov kauj ruam ntawm cov tshuaj tiv thaiv dawb radical feem ntau; Kauj Ruam 2 thiab 3 yog lub npe hu ua kev pib tshwm sim qhov twg cov ntaub ntawv dawb radical los ntawm homolysis. Homolysis tuaj yeem ua tiav los ntawm kev siv tshav kub lossis UV teeb thiab siv radical pib, piv txwv li. organic peroxides, azo tebchaw, thiab lwm yam. Cov kauj ruam kawg 6 thiab 7 yog sib sau ua ke hu ua kev txiav; ntawm no, cov radical nyhav recombine nrog lwm hom radical. Txawm li cas los xij, qee zaum radical reacts ntxiv qhov twg kev nthuav tawm tshwm sim. Kev nthuav tawm yog muab los ntawm qib 4 thiab 5 hauv daim duab saum toj no.
Qee yam piv txwv ntawm kev hloov pauv hloov pauv muaj xws li Barton-McCombie deoxygenation, Wohl-Ziegler cov tshuaj tiv thaiv, Dowd-Beckwith cov tshuaj tiv thaiv, thiab lwm yam.
Dab tsi yog Dawb Radical Ntxiv?
Dawb radical ntxiv yog ib hom tshuaj tiv thaiv ntxiv uas cov pab pawg ua haujlwm tau ntxiv rau qhov sib xyaw los ntawm cov dawb radical reactive intermediate. Hom kev sib ntxiv no tuaj yeem tshwm sim ntawm ib hom radical thiab ib hom tsis-radical lossis ntawm ob hom radical. Cov kauj ruam yooj yim ntawm cov dawb radical ntxiv suav nrog kev pib, kev nthuav tawm cov saw hlau, thiab kev txiav cov saw hlau.
Daim duab 02: Radical Ntxiv ntawm HBr ntawm Alkenes
Thaum lub sijhawm pib, tus thawj coj radical yog siv rau kev pib, qhov twg cov hom radical tsim los ntawm qhov tsis yog-radical precursor. Thaum lub sij hawm cov txheej txheem propagation, ib tug dawb radical nyhav reacts nrog ib tug non-radical hom nyob rau hauv thiaj li yuav tsim ib tug tshiab radical hom. Cov kauj ruam kawg yog kev txiav cov saw hlau, qhov twg ob lub radicals cuam tshuam nrog ib leeg, tsim kom muaj hom tsis muaj radical. Ib qho piv txwv ntawm hom tshuaj tiv thaiv no suav nrog Meerwein arylation.
Feem ntau, cov tshuaj tiv thaiv dawb radcal ntxiv yog ua raws li cov tshuaj reagents uas muaj cov ntawv cog lus tsis muaj zog kom lawv tuaj yeem raug homolysis tsim cov hom radical. Thaum muaj cov ntawv cog lus muaj zog, cov txheej txheem tshuaj tiv thaiv yuav txawv ntawm cov tshuaj dawb radical ntxiv ib txwm.
Dab tsi yog qhov txawv ntawm Kev Hloov Dawb Radical thiab Dawb Radical Ntxiv?
Ib qho dawb radical tuaj yeem yog atom, molecule, lossis ion uas muaj qhov tsis sib xws ntawm valence electron. Qhov sib txawv tseem ceeb ntawm kev hloov pauv dawb radical thiab dawb radical ntxiv yog qhov hloov pauv dawb radical cuam tshuam nrog kev hloov ntawm pab pawg ua haujlwm nrog lwm pab pawg ua haujlwm, thaum cov dawb radical ntxiv koom nrog kev sib ntxiv ntawm pab pawg ua haujlwm tshiab rau cov molecule.
Daim duab hauv qab no qhia qhov sib txawv ntawm kev hloov pauv dawb radical thiab dawb radical ntxiv rau hauv daim ntawv tabular rau ib sab sib piv.
Summary – Free Radical Hloov vs Dawb Radical Ntxiv
Ib qho dawb radical tuaj yeem yog atom, molecule lossis ion uas muaj cov khoom siv hluav taws xob tsis sib xws. Qhov sib txawv tseem ceeb ntawm kev hloov pauv dawb radical thiab dawb radical ntxiv yog qhov hloov pauv dawb radical cuam tshuam nrog kev hloov ntawm pab pawg ua haujlwm nrog lwm pab pawg ua haujlwm, thaum cov dawb radical ntxiv koom nrog kev sib ntxiv ntawm pab pawg ua haujlwm tshiab rau cov molecule.
