Electrophilic Hloov Pyridine

Pyridine yog lub nplhaib "π-deficient" heterocyclic, thiab nws cov huab cua electron ceev qis dua benzene, yog li nws cov kev hloov pauv electrophilic kuj tseem qis dua benzene, thiab nws yog piv rau nitrobenzene. Vim lub passivation ntawm nitrogen atoms ntawm lub nplhaib, tej yam kev mob ntawm electrophilic hloov cov tshuaj tiv thaiv yog hnyav thiab tawm los yog tsawg, thiab cov substituents feem ntau nkag mus rau 3 ( ) txoj hauj lwm.
Piv nrog rau benzene, cyclic electrophilic hloov pauv ntawm pyridine ua nyuaj dua, thiab cov neeg hloov pauv feem ntau nkag mus rau 3 () txoj hauj lwm, uas tuaj yeem piav qhia los ntawm cov txheeb ze ruaj khov ntawm qhov nruab nrab.
Kev hloov hluav taws xob ntawm pyridine yog qhov nyuaj dua li ntawm benzene vim tias muaj cov khoom siv hluav taws xob nqus nitrogen atoms thiab cov ions zoo ntawm cov nruab nrab tsis ruaj khov raws li cov khoom sib txuas sib txuas los ntawm benzene. Muab piv rau txoj haujlwm ntawm electrophilic reagent nres, nws tuaj yeem pom tau tias thaum tawm tsam 2 ( ) thiab 4 ( ) txoj haujlwm, cov txheej txheem nruab nrab muaj cov qauv txwv resonance uas tau them zoo rau ntawm electronegative nitrogen atom, uas tsis ruaj tsis khov, thiab lub 3( ) hloov nruab nrab tsis muaj qhov tsis ruaj tsis khov cov qauv no, thiab nws qhov nruab nrab yog qhov ruaj khov dua li qhov nruab nrab tawm tsam 2 thiab 4 txoj haujlwm. Yog li ntawd, cov khoom hloov pauv ntawm 3 txoj haujlwm tau yooj yim tsim.