Bond angle
Isn't benzene bulkier than those 2 CH3 grps. to cause more bond angle ?
17 Replies
@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.Ok, I'm not one to say this usually, but I do recommend a tiny bit of research before you post a doubt. Google can do wonders.
if benzene is bulkier so y the bond angle is lesser as compared to methoxymethane
i searched but it contradicts the relation b/w the bulkiness and bond angle
The second one is an exception where the methyl groups are bulky which causes repulsion between them making the bond angle greater
But don't know the correct reason to explain first one
what exactly is the exception u r talking about?
maybe resonance related reason
in phenol, 1 lone pair is in conjugation with the ring
in methoxymethane, there's 2 unscattered lone pairs
so i guess lonepair-lonepair repulsion causes the higher angle
i took H2O for explaining my pt. if lone lone pair repulsion is greater so the effective bond angle b/w COC should decrease
Methoxymethane is some ether exception iirc
oh right
hmm
yeah this is weird
shouldn't the LP-LP interaction be greater than BP-BP interaction, reducing the ether angle instead of increasing it
@Opt thoughts?
i think it's smthing to do with their hybridisation. Like in methoxymethane, o is sp3 and lp strongly repel ch bond so more bond angle. In phenol o is partially sp2 due to reso toh ussey mabe lp repulsion reduces and bond angle becomes closer to tetrahedral
Ok, not an amazing explanation on my behalf, and it's sort of unsatisfactory but the only thing I can think of is that in methoxymethane,
the compound exists as a superposition of its hyperconjugated structures right? So, there are net δ- charges on the carbons which are repelling each other, thereby increasing bond angle.
With phenol, resonating structures have no issue like this because on the other side, H doesn't have any electronic effects going on.
a superposition of its hyperconjugated structures means?
we good?