disagree with tbr ochem aldol condensation question

[echoyjeff222]

according to the book, it states that ketones can under condensation reactions. However, I've learned that the ketone cannot undergo the condensation because it is already more thermodynamically stable compared to the product ... should i just ignore this outside information when studying for the mcat?

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[sillyjoe]

You can definitely have a condensation of ketones. While the vast majority will not deprotonate, some will and you can utilize Le Chatelier Principle to increase the rate of the reaction. See the mechanism below, the first steps being condensation followed by dehydration

 

[echoyjeff222]

But just because some will deprotonate doesn't mean it'll actually react and self-condense. I'm saying that the final product is higher in energy than the reactants, so the equilibrium does not appreciably make any product. here's a resource I found that backs that up...

http://alpha.chem.umb.edu/chemistry/ch252/files/Overheads/Lecture_Chapter_17.pdf

"
– The product of ketone self-condensation is not obta
ined because the
equilibrium is not favorable"

 

[sillyjoe]

But just because some will deprotonate doesn't mean it'll actually react and self-condense. I'm saying that the final product is higher in energy than the reactants, so the equilibrium does not appreciably make any product. here's a resource I found that backs that up...

http://alpha.chem.umb.edu/chemistry/ch252/files/Overheads/Lecture_Chapter_17.pdf

"
– The product of ketone self-condensation is not obta
ined because the
equilibrium is not favorable"

That is for that specific reaction of an aldehyde and a ketone Claisen-Schmidt condensation, which is a subcategory of aldol condensations), not a general rule about whether or not ketone condensation can happen. Do some more research on aldol condensations and you will see that both aldehydes and ketones can participate in it.