Acidity

[limukbohil]

I don't understand why carboxylic acid is more acidic than diketone with 2 alpha protons adjacent to 2 carbonyls

 

Shouldn't the two ketones have more inductive effect on the alpha protons than one ketone and one hydroxide?

 

Thank you for the help ^^

[John Cuthber]

Do you understand why methanol is a much stronger acid than methane?

[limukbohil]

Yes

Mehtanol is more acidic than methane because of the oxygen (higher electronegativity) right?

 

I know that the hydrogens outside of the two ketones are less likely to disociate than the carboxylic acid hydrogens (i think). But the two alpha hydrogens in between two ketones, aren't they more likely to dissociate?

 

Wait... is hydroxly group more electronegative than a ketone?

Does acidity have to be related to the alpha hydrogens?

 

Now that i look at it... idk T.T

 

-Thanks for the help

[John Cuthber]

The 2 hydrogens on the carbon between the 2 keto groups are relatively acidic, but not as much so as a carboxylic acid.

If you want to make a strong acid you have to make something that loses a proton easily, that will leave it negatively charged (unless it started off positive).

Oxygen is very electronegative and doesn't mind having that negative charge, so protons atached to oxygen are usually quite acidic. On the other hand protons atached to carbon are not so acidic because carbon isn't so electronegative.

 

When you take the proton off a carboxylic acid you are left with the carboxylate ion which can share the negative charge directly across 2 oxygens. That's a better bet than having it on a carbon and palming some of it off on 2 oxygens.