simple question about acidity

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What's more acidic? An ether, or an aldehyde?

e.g. CH3-O-CH3 vs. CH3CHO


Thanks!

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What's more acidic? An ether, or an aldehyde?

e.g. CH3-O-CH3 vs. CH3CHO


Thanks!
The aldehyde is more acidic. And the acidic proton is NOT the aldehyde one (i.e., the one attached directly to the carbonyl). It's the methyl group protons that are acidic.
 
The aldehyde is more acidic. And the acidic proton is NOT the aldehyde one (i.e., the one attached directly to the carbonyl). It's the methyl group protons that are acidic.

:thumbup: It has to do with the electron pull away from the methyl by the carbonyl/aldehyde or something like that. It leaves one of the methyl protons feeling less welcome.
 
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The aldehyde is more acidic. And the acidic proton is NOT the aldehyde one (i.e., the one attached directly to the carbonyl). It's the methyl group protons that are acidic.

Q,

Just a curious question, but the acidity of an ether and aldehyde and other organic groups can also be explained in terms of their electron withdrawing and electron donating capacities right???
 
Ethers are not very acidic at all. Remember that acids are supposed to be good at donating protons.

I've always wondered, is there a general acidity spectrum of organic compounds?

(Most acidic) Carboxlylic acids > Aldehydes > Alcohols > Esters > Ketones > Ethers > Alkanes (Least acidic)

Something like this?? :confused:
 
Q,

Just a curious question, but the acidity of an ether and aldehyde and other organic groups can also be explained in terms of their electron withdrawing and electron donating capacities right???
Yes. A carbonyl is electron withdrawing, while an alkoxy group is donating. So you could explain their relative acidities in terms of whether they stablize or destabilize the conjugate base's negative charge.
 
Ethers are not very acidic at all. Remember that acids are supposed to be good at donating protons.

I've always wondered, is there a general acidity spectrum of organic compounds?

(Most acidic) Carboxlylic acids > Aldehydes > Alcohols > Esters > Ketones > Ethers > Alkanes (Least acidic)

Something like this?? :confused:
Yes, except that alcohols are usually more acidic than aldehydes, and the acidities of carbonyl compounds overlap with one another. Also, don't forget about alkynes; they're fairly acidic as far as hydrocarbons go. So I would make your list like this:

(most acidic) carboxylic acids > alcohols > alpha protons of carbonyls (esters, aldehydes, and ketones) > alkynes > ethers > alkanes (least acidic)
 
Yes, except that alcohols are usually more acidic than aldehydes, and the acidities of carbonyl compounds overlap with one another. Also, don't forget about alkynes; they're fairly acidic as far as hydrocarbons go. So I would make your list like this:

(most acidic) carboxylic acids > alcohols > alpha protons of carbonyls (esters, aldehydes, and ketones) > alkynes > ethers > alkanes (least acidic)

Don't forget to add in phenol!

You know you have to put in the aromatic factor too.

More fun!!
 
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