+R -I of benzene
Um... it's kinda troubling to me that if we say overall effect of benzene is -I then how's benzenoic acid less acidic than formic acid...
Additionally I even saw that we can just find conjugate like in benzoic acid coo- forms and coo- starts to give +I which is balanced in it but the same ain't even balanced in formic acid so shouldn't it be less acidic??
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@Dexter
Note for OP
+solved @user1 @user2... to close the thread when your doubt is solved. Mention the users who helped you solve the doubt. This will be added to their stats.@Dexter
Note for OP
+solved @user1 @user2... to close the thread when your doubt is solved. Mention the users who helped you solve the doubt. This will be added to their stats.But benzene can show +R as well? Think of it in that way na
Resonance effect dominates
Where!?
So it destabilises the negative charge on In benzoic acid
Where as in formic acid there is no such effect that why it thr conjugate base or COO- is more stable
How to consider where +R is seen and where -I is to be seen
Resonance effect dominates then hyper then Inductive In general
If there is Reso as well as inductive
First we’ll check resonance effect
Um... sorry brother but...can u just show me it out through ur notebook as I have learnt -I>-R>+R>+I
I dont hve any notes for this sorry
This order is for what?
Well it's just a strength order...like for which one is more dominant over the other
eh i don’t remember anything like that lol
all i remember is that first we gotta check Resonance effect
+ or - k liye opposite hote h
Anyways let just someone else ans it
as you can see,
in the conjugate base of Formic Acid, the negative charge is on Oxygen 100% of thr time, and has 2 equivalent resonating structures.
in the conjugate base of Benzoic Acid, the negative charge (if you draw all the resonating structures) doesn't exist in Oxygen 100% of the time, so since Oxygen is more electronegative than Carbon, the "quality" of Resonance decreases.
Also, Counter Resonance is observed in the conjugate base of Benzoic Acid, as shown in the picture.
are you sure it's not for some specific case or something? Because the strength of Resonance Effect is always greater than Inductive Effect as Inductive effects depend on distance and only cause partial polarization of the bond, whilst in Resonance, there is actual transfer of the electrons(π electrons)
First of all cross reso means something like this
Lemme just verify for all of u then
Ok ok I even got that section of my notes jisse pta lg gya ki cross bhi hota h😅😅
And um...secondly about this... here's wht I have right now...
that pretty peculiar, benzene shows +R and it dominates over -I so the conjugate base formed in benzenoic acid is less stable making it less acidic than a formic acid
@Enamine can u plz just look upto this
I'll see bich me time Mila to
I told "Counter Resonance" not "Cross Conjugation", slight difference.
Counter Resonance decreases the stability because the two electron flows are in a way against each other.