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Jasmine
Jasmine
04:39
@ScientistOmega Sorry , was thinking incorrect
By hyper conjugation logic , 2 is more stable as one of double bond is stabilized by 8 alpha H
Scientist Omega
Scientist Omega
05:05
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@YUSUFHASAN in this compound 2 is more stable. Is it due to more ring Strain in 1??
YUSUF HASAN
YUSUF HASAN
05:57
@ScientistOmega one quick way to see is by hyperconjugation like jasmine said. Another way is to draw a chair form of the mooecules,and see that the double bond fixes the trans conformation which is not there in 1
 
9 hours later…
Scientist Omega
Scientist Omega
14:30
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Is there any trick to predict whether a compound is +M<-I or +M >-I in such complicated compounds??
I can do for most of compounds but to predict in some compounds it's really difficult.My teacher told me too just learn these cases as exceptional.
 
1 hour later…
YUSUF HASAN
YUSUF HASAN
15:46
@ScientistOmega How much MO theory do you know?
111
111
16:17
@YUSUFHASAN jee level only!!
@YUSUFHASAN it's me scientist omega
YUSUF HASAN
YUSUF HASAN
@111 Ok, well, the thing is, donation depends on effective overlap mostly. The thing is, electronegativity is a bonded phenomenon, it's not applied to O's own lone pairs. You are imagining that since O is more electronegative than Cl, so +M will decrease..But the fact is, electronegativity of O or Cl is not applied on it's own lone pairs, so here it simply depends on the overlap strength , which is weaker in C-Cl than C-O
"Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons."
That's the technicality to look at here
111
111
why C-O overlap is more than C-Cl??
Cl size is larger than O.Means more polarisation so a stronger bond.
Am i wrong??
YUSUF HASAN
YUSUF HASAN
16:34
@111 Nope,overlap strength is basically measured in terms of compatibility.. in C-O,overlap is of 2pπ-2pπ type,while in C-Cl it's of 20π-3pπ type
111
111
oops**
YUSUF HASAN
YUSUF HASAN
2pπ-2pπ is better because 3p orbital is much more diffused than 2p
Hence overlap integral is less
111
111
Thanku
YUSUF HASAN
YUSUF HASAN
Welcome :)
 
2 hours later…
111
111
18:31
Consider this reso structures of benzoic acid
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As we can see that + charge is at Ortho and Para positions of benzoic acid.
So EWG at Para position must destabilize it.
Hence benzoic acid with ERG at para must make it strongest acid.
BUT it isn't correct.Why?? please explain.
Sir told to consider - charge only on COO- .So EWG will increase stability and acidic strength. But i want to know y i'm wrong??
 
3 hours later…
YUSUF HASAN
YUSUF HASAN
22:16
@111 Your proposed resonance structures have negligible contribution to the resonance hybride of the benzoate anion
This is because,the 3rd structure you have made,has a dianion on the same central atom, a VERY unfavorable intermediate,plus ,your positive charge is on the other end of the molecule,so the charge separation is off the charts here
Hence,what we generally say is that the resonance is within COO- itself,and COO- is essentially an ERG
Hence,if there is an EWG to capture the electrons displaced by COO-,it becomes quite like a "source and sink" flow of electrons,which will be quite stable

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