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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: sharbeldam on June 14, 2021, 06:59:58 PM

Title: Synthesis problem
Post by: sharbeldam on June 14, 2021, 06:59:58 PM

I have this dicarbonyl, i tried everything to get to that product, nothing works, i think the obvious first move is aldol, after that I can do oxidation, haloform reaction... and many other options, but nothing works, how can i get two methyls?? any hints at all?

Title: Re: Synthesis problem
Post by: sharbeldam on June 14, 2021, 07:15:47 PM

Edit : another thought, please tell me if im right.
1) aldol
2) haloform
3) oxidation of the alcohol so it can become ketone
4) decarboxylation
5) alpha alkylation (+CH3)
6) reducing my ketone back to alcohol
7)PBr3 --> Mg --> Alcohol becomes MgBr
8) CO2 so i get carboxylic acid
9) I reduce the CA and eliminate the alcohol + H2/pd

Title: Re: Synthesis problem
Post by: rolnor on June 15, 2021, 01:14:21 AM

What about the carbon alpha to the aldehyde attacking the kenone carbonyl first?

Title: Re: Synthesis problem
Post by: sharbeldam on June 15, 2021, 03:07:24 AM

I dont know why but that made me laugh, i did 9 steps for nothing, thanks rolnor !!

Title: Re: Synthesis problem
Post by: Meter on June 15, 2021, 03:45:41 AM

Quote from: sharbeldam on June 15, 2021, 03:07:24 AM

I dont know why but that made me laugh, i did 9 steps for nothing, thanks rolnor !!

Aldehyde alpha carbons are more acidic than ketone alpha carbons. Something to keep in mind for these types of problems.

Title: Re: Synthesis problem
Post by: rolnor on June 15, 2021, 03:58:07 AM

No problem!