Note this people. Lone pair will participate in the resonance of cyclic ring if the central atom is perpendicular (Not parallel to a double bond) so it will tuck inside the cyclic ring and participate resonance. The one will not participate are parallel to double bonds so it will stabilize itself and go outside the cyclic ring and therefore, will not participate resonance. THE ONE THAT PARTICIPATES RESONANCE ARE COUNTED IN HUCKEL'S RULE AND THE LONE PAIR OUTSIDE THE CYCLIC WILL NOT BE INCLUDED IN HUCKEL'S RULE
Nitrogen with connected H is sp2 hybridized and form 3 bonds (two with C and one with H) so this nitrogen still posses 2 pz electrons which could add to aromatic ring. Second nitrogen is also sp2 hybridized but form 2 bonds with C, so last bond is a lone pair with 2 electrons, so this nitrogen posses only 1 electron pz, which can be added to aromatic ring. This unbalance derived from fact, because first nitrogen construct sigma bond with H with its own electron. It is just like I it see.
Imidazole : Isnt the nitrogen bonded to a hydrogen in sp2 without resonance, because it has 3 sigma and 1 lone pair. The 3 sigma come from the s +p +p in sp2 and the lone pair is still on the last p orbital remaining. This accounts for all 7 electrons of nitrogen. So you have 3 hybridized electrons to make 3 sigma and 2 unhybridized electrons that create the 2 pi electrons. Resulting in 6 pi-electrons to make it aromatic. Looking back at it the 2 unhybridized electrons are on 1 p orbital and are in opposite spin so does this not make it a sp2 therefore it has to make a sp3 so no 2 electrons are in 1 p orbital am i right or wrong someone explain plz
Sir i have a question why sp2 hybrirdized orbitals only involve in resonance why not that unhybridized orbital. Is electron enough smart to detect which is hybridized and which is not? The elctron is a wave or a particle here. Hehe.
Note this people. Lone pair will participate in the resonance of cyclic ring if the central atom is perpendicular (Not parallel to a double bond) so it will tuck inside the cyclic ring and participate resonance. The one will not participate are parallel to double bonds so it will stabilize itself and go outside the cyclic ring and therefore, will not participate resonance. THE ONE THAT PARTICIPATES RESONANCE ARE COUNTED IN HUCKEL'S RULE AND THE LONE PAIR OUTSIDE THE CYCLIC WILL NOT BE INCLUDED IN HUCKEL'S RULE
Really needed a sulfur example - thank you!
00:03:40 Imidazole
Actually i want to see pyrazole chemical reactions so pls send me link from where i can get it
A great lesson, thanks! "anyone who has allergies has heard of Histamine"
Nitrogen with connected H is sp2 hybridized and form 3 bonds (two with C and one with H) so this nitrogen still posses 2 pz electrons which could add to aromatic ring.
Second nitrogen is also sp2 hybridized but form 2 bonds with C, so last bond is a lone pair with 2 electrons, so this nitrogen posses only 1 electron pz, which can be added to aromatic ring. This unbalance derived from fact, because first nitrogen construct sigma bond with H with its own electron.
It is just like I it see.
Imidazole :
Isnt the nitrogen bonded to a hydrogen in sp2 without resonance, because it has 3 sigma and 1 lone pair. The 3 sigma come from the s +p +p in sp2 and the lone pair is still on the last p orbital remaining. This accounts for all 7 electrons of nitrogen.
So you have 3 hybridized electrons to make 3 sigma and 2 unhybridized electrons that create the 2 pi electrons. Resulting in 6 pi-electrons to make it aromatic.
Looking back at it the 2 unhybridized electrons are on 1 p orbital and are in opposite spin so does this not make it a sp2 therefore it has to make a sp3 so no 2 electrons are in 1 p orbital am i right or wrong someone explain plz
could you make a video explaining why furan and thiophene are aromatic, while pyran and thiopyran are not (only their ionic forms are aromatic) ?
+Szabolcs Varga Both (pyran and thiopyran) consist a sp3 hybridized C-atom, therefore they're not aromatic.
Sir i have a question why sp2 hybrirdized orbitals only involve in resonance why not that unhybridized orbital. Is electron enough smart to detect which is hybridized and which is not? The elctron is a wave or a particle here. Hehe.