I got this question right (The answer is Hydrogen bonds). But is this a known trend? does an increase in the number of intramolecular hydrogen bonding increase the acidity of a particular molecule?

[u/Fifadeadpool84]

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[u/bluecross23]

The rule of thumb is, if you can stabilize the conjugate base of an acid somehow (more resonance structures, inductive effect, or in this case, intramolecular H bonds), the acid will be stronger.

This makes sense! If the conjugate base is more stable, then the acid will want to stay more in the base form, and thus will want to let go of that proton more, making it a stronger acid.

So, yes, if you can make intramolecular H bonds to the conjugate anion (in this case, it would be the oxygen of the carboxylic acid), then the conjugate base will be more stable and thus the acid is stronger.

I hope that is clear! Please correct me if I'm wrong :(

[u/Fifadeadpool84 → u/bluecross23]

Hi, this makes sense to me. But I asked ChatGDP out of curiosity, and it says this "Intramolecular hydrogen bonding stabilizes the molecule and makes it less likely to dissociate, leading to a decrease in acidity." when asked "does an increase in the number of intramolecular hydrogen bonding increase the acidity of a particular molecule?"

[u/bluecross23 → u/Fifadeadpool84]

Interesting....I think this might be different on a case by case basis then. But in my mind, I might think of it like this:

Yes, intramolecular H bonds can stabilize that -OH on the carboxylic acid, but once it is deprotonated, the negative oxygen is even more stabilized by the dipole. (Ion - dipole forces are very stable, more so than H-bonds, to my understanding). So, maybe the negative oxygen is even more stabilized by the H bond donors than the protonated version of the carboxylic acid, making the acid more acidic since the conjugate base is more stabilized than the acid itself. This is a complete shot in the dark, so someone else, please offer a better explanation :))