Qhov sib txawv tseem ceeb ntawm thawj theem nrab thiab theem nrab halogenoalkanes yog txoj haujlwm ntawm cov pa roj carbon atom uas nqa lub halogen atom. Hauv thawj halogenoalkanes, cov pa roj carbon atom, uas nqa lub halogen atom, txuas rau tsuas yog ib pawg alkyl. Tab sis, hauv theem nrab halogenoalkanes, cov pa roj carbon atom txuas rau ob pawg alkyl. Whereas, nyob rau hauv tertiary halogenoalkanes, cov pa roj carbon atom txuas rau peb pawg alkyl.
Halogenoalkanes lossis haloalkanes yog alkanes uas muaj halogens. Halogens yog cov tshuaj lom neeg ntawm pawg 17 ntawm lub sijhawm teem sijhawm. Nws suav nrog fluorine (F), chlorine (Cl), bromine (Br), iodine (I), thiab astatine (At). Muaj peev xwm muaj ib lossis ntau dua halogens hauv tib lub haloalkane. Muaj ntau cov ntawv thov tseem ceeb ntawm halogenoalkanes ua cov nplaim hluav taws, tua hluav taws, cov tub yees, cov khoom siv hluav taws xob, thiab lwm yam. Txawm li cas los xij, ntau lub haloalkanes raug suav tias yog cov tshuaj lom thiab cov pa phem.
Primary Halogenoalkanes yog dab tsi?
Primary halogenoalkanes yog cov organic tebchaw uas muaj cov pa roj carbon atom txuas rau ib pawg alkyl thiab ib lub halogen atom. Yog li ntawd, cov qauv ntawm cov thawj halogenoalkanes yog R-CH2-X; R yog ib pawg alkyl thaum X yog halogen. Peb tuaj yeem txhais lawv li 10 haloalkanes. Ib qho piv txwv yog ib qho halothane, uas muaj ib pawg ethyl li pawg R thiab chlorine atom li X pawg lossis halogen. Txawm li cas los xij, methyl halides yog ib qho kev zam rau cov qauv halogenoalkanes thawj zaug vim tias lawv muaj peb lub hydrogen atoms txuas rau carbon atom uas nqa cov halogen atom. Qhov no txhais tau tias, tsis muaj cov pab pawg alkyl txuas nrog cov tebchaw no. Tab sis lawv raug suav tias yog thawj haloalkanes.
Ntxiv mus, yog tias peb xav txog qhov reactivity ntawm thawj halogenoalkanes, cov pa roj carbon atom, uas txuas rau lub halogen atom, yog ib qho chaw reactive vim hais tias cov halogen yog electronegative ntau dua carbon; Yog li, nws muab ib feem zoo nqi rau cov pa roj carbon atom los ntawm kev nyiam cov nyiaj electrons rau nws tus kheej. Tsis tas li ntawd, cov tebchaw no tuaj yeem tawm tsam los ntawm nucleophilic reagents uas nrhiav cov nqi zoo. Yog li, qhov no ua rau muaj kev hloov pauv nucleophilic. Thiab, qhov tshuaj tiv thaiv no muaj lub zog ua kom muaj zog tiv thaiv siab. Nws yog hom tshuaj tiv thaiv SN2, thiab peb lub npe nws ua cov tshuaj tiv thaiv bimolecular.
Halogenoalkanes Secondary yog dab tsi?
Secondary halogenoalkanes yog cov organic tebchaw uas muaj cov pa roj carbon atom txuas rau ob pawg alkyl thiab halogen atom. Cov qauv ntawm cov halogenoalkanes theem nrab yog R2-C(-H)-X. Ntawm no, ob pawg alkyl (R pawg) tuaj yeem ua tau zoo sib xws lossis ntau pawg. Peb tuaj yeem txhais cov ntsiab lus no ua 2 0haloalkanes. Ntxiv mus, theem nrab halogenoalkanes tau txais SN2 nucleophilic hloov cov tshuaj tiv thaiv. Yog li ntawd, lawv yog cov tshuaj bimolecular.
Daim duab 02: 2-Bromopropane
Lub reactivity ntawm theem nrab haloalkane nyob rau hauv nruab nrab ntawm cov reactivities ntawm thawj thiab tertiary halogenoalkanes vim tias muaj ob pawg alkyl txo tus nqi zoo ntawm cov pa roj carbon atom vim alkyl pawg yog electron rho tawm hom.
Tertiary Halogenoalkanes yog dab tsi?
Tertiary halogenoalkanes yog cov organic tebchaw uas muaj cov pa roj carbon atom txuas rau peb pawg alkyl (tsis muaj hydrogen atoms txuas ncaj qha rau cov pa roj carbon) thiab halogen atom. Cov qauv dav dav rau tertiary haloalkane yog R3-C-X, qhov twg peb pawg R (alkyl pawg) tuaj yeem yog tib pawg lossis ntau pawg. Peb tuaj yeem txhais cov ntsiab lus no ua 30 haloalkanes. Ntxiv mus, cov tebchaw no tau txais SN1 nucleophilic hloov pauv cov tshuaj tiv thaiv. Tab sis, qhov txheej txheem no txawv ntawm cov nucleophilic hloov pauv cov tshuaj tiv thaiv ntawm thawj thiab theem nrab halogenoalkanes.
Cov pa roj carbon atom uas nqa lub halogen atom muaj qhov zoo qis heev vim tias muaj peb pawg electron rho tawm txuas nrog cov pa roj carbon atom. Yog li ntawd, nws tsis tas yuav tsim cov khoom siv hluav taws xob siab, thiab cov nucleophile tuaj yeem tawm tsam cov carbonium ion ncaj qha thaum nws tsim. Yog li, qhov no yog vim li cas peb thiaj hu nws ua ib qho tshuaj tiv thaiv tsis muaj zog.
Qhov txawv ntawm Thawj Tsev Kawm Ntawv Qib Siab thiab Tertiary Halogenoalkanes yog dab tsi?
Halogenoalkanes muaj peb hom nyob ntawm tus qauv; thawj, theem nrab, thiab tertiary halogenoalkanes. Hauv thawj halogenoalkanes, cov pa roj carbon atom uas nqa lub halogen atom txuas rau tsuas yog ib pawg alkyl, thiab nyob rau hauv theem nrab halogenoalkanes, cov pa roj carbon atom txuas rau ob pawg alkyl, thaum nyob rau hauv tertiary halogenoalkanes, cov pa roj carbon atom txuas rau peb pawg alkyl. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm thawj theem nrab thiab theem nrab halogenoalkanes.
Ua raws li infographic qhia txog qhov sib txawv ntawm thawj theem nrab thiab theem nrab halogenoalkanes.
Summary – Lub Tsev Kawm Ntawv Qib Siab Qib Siab vs. Tertiary Halogenoalkanes
Muaj peb hom halogenoalkanes nyob ntawm tus qauv; thawj, theem nrab, thiab tertiary halogenoalkanes. Qhov sib txawv tseem ceeb ntawm thawj theem nrab thiab theem nrab halogenoalkanes yog tias nyob rau hauv thawj halogenoalkanes, cov pa roj carbon atom, uas nqa cov halogen atom, txuas rau tsuas yog ib pawg alkyl. Thiab, hauv theem nrab halogenoalkanes, cov pa roj carbon atom txuas rau ob pawg alkyl. Lub caij no, hauv tertiary halogenoalkanes, cov pa roj carbon atom txuas nrog peb pawg alkyl.
