Are alkoxide ions better bases than hydroxide ions?

This forum made possible through the generous support of SDN members, donors, and sponsors. Thank you.

Padfoot

Full Member
10+ Year Member
Joined
Dec 20, 2010
Messages
93
Reaction score
19
There's a question that says a stronger base is sometimes needed for the second alkylation of an acetoacidic ester, and the passage shows NaOEt as the first base and NaOH as the second. But I thought that an alkoxide ion should be more basic because its carbon atoms donate more electron density toward the oxygen, making it more basic.
 
One could look up the pka of water to be around 15.7 and of ethanol to be around 16.

Since lower pka corresponds to weaker conjugate base, I would've agreed with you and said ethoxide is a slightly stronger base than hydroxide.

I was slightly perplexed by what your passage said so I did a little more reading.

It appears that all alkoxides are stronger bases than hydroxide, with the exception of methoxide - which is slightly weaker.

So I think you are correct and the passage seems off - though in general they are almost equivalent in strength.
 
Top