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do you know about the molecular orbital theory?
yes
you can do it by checking quasiaromaticity
Waht bro waht
distribute the pi bond
and if you attain aromaticity that is 🔥
I don't get it
now?
I’m curious what about a and b
-I order, more N more -I
@ᴘɪᴄᴄʜɪ | 🎧 🎶 i think that bot didnt reply here
uss time issues the
abse ho toh btana
oh okay
:salute:
One could do it with HOMO LUMO but that would be out of scope for jee purposes where you have to simply check via delocalisation and electronic effects
so is quasiaromaticity the right way to determine two of them?
Yes
shall we mark this one as solved?
Ask the dosa eater maybe
Wait I’ll sum it up though
If u split the double bond heterolytically (giving Nitrogen the negative charge since it is more electronegative), rings a and b will be aromatic, c will have 2 aromatic rings (above one being quasi-aromatic hence even more stable than normal aromatic rings) and d will have 1 aromatic and 1 anti-aromatic ring
Hence c is the most basic and d is the least basic
Now for a and b you gotta check the inductive effect of nitrogen (the lone pairs won’t be delocalised so you cannot take mesomeric effect into account). In that case since a has more Nitrogens, there is more withdrawal of electron, and hence is less basic than b
Final order becomes c > b > a > d
Explanation via HOMO LUMO (gives a more concrete idea):
For an acid base reaction there should be less HOMO (of base) and LUMO (of acid) gap (HOMO is highest occupied molecular orbital and LUMO is lowest unoccupied molecular orbital) since the electron goes from pi mo of base to the acid. So basicity is given by the energy of HOMO of the bases. More the HOMO energy more the basicity since lesser the HOMO LUMO gap. Now if you understood this, you need to know when is energy of HOMO lowered in a pi system. In this case, Nitrogen is highly electronegative and exerts -I effect, it decreases the energy of HOMO of the base. Since A and D have more Nitrogens, they are comparatively weaker than B and C. Now choosing between A and D, D has more delocalisation so energy of HOMO is lowered.
Between B and C, delocalisation of C is higher so B is the better base.
Final order: c>b>a>d
@MGK we good?
Yeah all set
Sorry I forgot to inform @iTeachChem
+solved @!Nimay¡
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