Ranking Acidic Protons in Ochem

[jonathankimmm]

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Hey there I was doing destroyer and a couple questions came up on asking w hich proton was the most acidic in given molecule.

Can anyone explain how to figure this out? I tried looking for like a sheet or a ranking chart online but couldn't find anything concrete

 

[SicEm]

Usually if there's an electron withdrawing group nearby it will make the proton more acidic. It's like it's pulling the acidic proton's bond away from it so its more likely to release. Also, it will be more acidic if the conjugate base can be resonance stabilized. Somebody correct me if I'm wrong but that's my understanding...

 

[dpat93]

the closer it is to an electron withdrawing group, the more acidic it is. This is a general rule of thumb, not a law.


Example: C-O-H vs C-C-H

the first compound has the more acidic hydrogen because it is bound to an oxygen while the other one is bound to a carbon, a weakly withdrawing group.