1,3 dicarbonyls?

[obgyny]

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So on AAMC's content outline, it lists under important reactions for aldehydes and ketones:
"1,3-dicarbonyl compounds, internal hydrogen bonding"

What should we know about this besides the internal hydrogen bonding? I can't find anything about this in my TPR book.

I've actually noticed that there are several topics in the AAMC's content outline for Orgo that are not mentioned in TPR book, so I'm googling them 😛

Thanks in advance!

 

[boaz]

The first two things that come to mind are:

1) acidity of the hydrogen on the carbon between the carbonyls.

2) the potential for decarboxylation, if one of the carbonyls is actually a carboxylate.

 

[BerkReviewTeach]

So on AAMC's content outline, it lists under important reactions for aldehydes and ketones:
"1,3-dicarbonyl compounds, internal hydrogen bonding"

What should we know about this besides the internal hydrogen bonding? I can't find anything about this in my TPR book.

I've actually noticed that there are several topics in the AAMC's content outline for Orgo that are not mentioned in TPR book, so I'm googling them 😛

Thanks in advance!

Pages 44-45 in Oragnic Book II address this type of reaction. Consider acetacetic ester and malonic ester synthesis pathways, where the alpha proton (alpha to both carbonyls) is deprotonated to make a great nucleophile, which can then react with one of several possible electrophiles to add an R-group. The product can then be further modified by hydrolyzing the ester into a beta-keto acid, and then the keto acid can undergo decarboxylation with heat. Decarboxylation is explained in part by the intramolecular hydrogen bonding. There really isn't much these do beyond the pathways shown on those two pages.

Also, passage 13 on pages 69-70 shows how the reaction can be coupled with two possible second steps and the questions that go with those reactions. That's a very important passage to do and should summarize all you need to know.

 

[obgyny]

Pages 44-45 in Oragnic Book II address this type of reaction. Consider acetacetic ester and malonic ester synthesis pathways, where the alpha proton (alpha to both carbonyls) is deprotonated to make a great nucleophile, which can then react with one of several possible electrophiles to add an R-group. The product can then be further modified by hydrolyzing the ester into a beta-keto acid, and then the keto acid can undergo decarboxylation with heat. Decarboxylation is explained in part by the intramolecular hydrogen bonding. There really isn't much these do beyond the pathways shown on those two pages.

Also, passage 13 on pages 69-70 shows how the reaction can be coupled with two possible second steps and the questions that go with those reactions. That's a very important passage to do and should summarize all you need to know.

Which book are you referring to? TBR (assuming from your username lol)? Because I'm using the Princeton Review books...

 

[BerkReviewTeach]

Which book are you referring to? TBR (assuming from your username lol)? Because I'm using the Princeton Review books...

If I ever try to give any sort of reading advice, please disregard it. I misread not once, but twice, in your original post. I thought you typed TBR, not TPR.

It's still true though that everything you need to worry about is based on the increased acidity of being conjugated to two carbonyls and that the subsequent carbanion is a great nucleophile for attacking alkyl halides and/or another carbonyl compound.

You should also note the potential to hydrolyze if one of the carbonyls is an ester and the potential for the ketoacid to undergo decarboxylation.

 

[obgyny]

If I ever try to give any sort of reading advice, please disregard it. I misread not once, but twice, in your original post. I thought you typed TBR, not TPR.

It's still true though that everything you need to worry about is based on the increased acidity of being conjugated to two carbonyls and that the subsequent carbanion is a great nucleophile for attacking alkyl halides and/or another carbonyl compound.

You should also note the potential to hydrolyze if one of the carbonyls is an ester and the potential for the ketoacid to undergo decarboxylation.

Lol I figured... they really should reconsider changing the names TPR and TBR. Thanks for the advice!! I'm really frustrated with TPR orgo right now... so many topics they didn't mention! The other sections in the TPR books are pretty good, it's just orgo 🙁.