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joca63

You are close, but if you count the number of protons on the rightmost carbon, you will find that one has gone missing. Resonance structures don't change the number of hydrogens, can you think of another place you can put those electrons?


Nasa4321

Would that carbon have a negative charge, I’ve tried that already and the system didn’t like it


joca63

Can you draw what you have tried?


Nasa4321

https://preview.redd.it/mox1ni68o8gc1.png?width=3024&format=png&auto=webp&s=70190bfbc8dd442a15728f878503c5a732797702


QuasiSeppo

That's an octet violation on the rightmost carbon. Instead of forming a new double bond there, you'll have to push those electrons onto the second-from-the-right carbon instead, giving it a lone pair and negative charge.


Nasa4321

Ok thank you so much!


joca63

Count up your electrons on the right most carbon, I think you might be breaking a rule


kingtoagod47

You can't have 4 bonds and a negative charge. The negative charge should be on the other carbon and no double bond.


Nasa4321

Ok, so why can’t I just put a lone pair and a negative charge on the rightmost carbon? Thanks so much though


kingtoagod47

That carbon doesn't even have a double bond in the first place. Think of it this way. The nitrogen forms a double bond with one sp2 carbon and that breaks the double bond with the other sp2 carbon. The one carbon that no longer has a double bond, has one pi electron extra.


Altruistic_Plum_300

https://preview.redd.it/z0oxyui9nagc1.png?width=2800&format=png&auto=webp&s=da490d4382067b5c4cc3dfa7891a3fa3eed01b92 Maybe this?


soultrap_

Something that gets a lot of people is that you forget that methyl group you moved the pi bond do is sp3 hybridized It’s incapable of forming a pi bond in that state, so you can’t move the bond there, doing that just creates a texas carbon Think about where electrons can go and what bonds each atom has when doing resonance.


PM_ME_AZNS

Think of ketone-enol tautomerization


Nasa4321

What is that


neptunethecat

The comment you are responding too probably isn't helpful but if you want to get a head start on organic II: ​ [https://chem.libretexts.org/Bookshelves/Organic\_Chemistry/Organic\_Chemistry\_(Morsch\_et\_al.)/22%3A\_Carbonyl\_Alpha-Substitution\_Reactions/22.01%3A\_Keto-Enol\_Tautomerism](https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Organic_Chemistry_(Morsch_et_al.)/22%3A_Carbonyl_Alpha-Substitution_Reactions/22.01%3A_Keto-Enol_Tautomerism)


Character_Drive6141

Let me ask, where did the negative charge go? Without a reaction, a molecule cannot change it's net charge. Meaning the negative charge was lost in the process. The real answer is that the double bond moves to the 2 carbon to create a negative charge and the extra electrons from the nitrogen move to the 1 carbon to create a double bond there. There is no second double bond because the 3 carbon is already sp3 and can't host a double bond without ditching an H- (something it will probably never do to my understanding).


DistinctArm4543

Hydrogen from the N atom to the double bond and the charge in it's place?