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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: egilbreth on March 30, 2020, 04:04:47 PM

Title: Would this synthetic pathway be possible?
Post by: egilbreth on March 30, 2020, 04:04:47 PM
OC(=O)CCC(=O)O :rarrow:(Br2,hv)OC(=O)C(Br)CC(=O)O :rarrow:(NaOH, Δ) OC(=O)C=CC(=O)O :rarrow:(H2SO4,H2O)OC(=O)C(O)CC(=O)O :rarrow:(CrO3, H2SO4) OC(=O)C(=O)CC(=O)O :rarrow:(Δ)OC(=O)C(O)=C + O=C=O

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OC(=O)C(O)=C  :rarrow: (H2,Ni) OC(=O)C(O)C :rarrow:(H2SO4, Δ) OC(=O)C=C:rarrow: (H2,Ni) OC(=O)CC

I think it's possible but I was unsure if there would be problems when trying to brominate the original acid and if adding a ketone to split it like that would even be possible. Any feedback is much appreciated
Title: Re: Would this synthetic pathway be possible?
Post by: rolnor on March 30, 2020, 04:26:53 PM
There are many steps one could comment but the fifth step is questionable, what you have is pyruvic acid but you draw it as an enol-form;
https://en.wikipedia.org/wiki/Pyruvic_acid

One thing that could be very difficult is the work-up, you have very polar compounds and H2SO4 and cromium-salts, have you thought about that? Also I see risc of decarboxylation in some steps.

Title: Re: Would this synthetic pathway be possible?
Post by: egilbreth on March 30, 2020, 04:43:13 PM
With respect to the pyruvic acid would it be possible to preform a wolf-kishner to eliminate the ketone instead of what I did in the bottom section? Or just to clarify would the pyruvic acid automatically decarboxylate because of the β carbonyl group?
Also would PCC work better than the H2SO4 and cromium-salt or does that run into the same issue because of the polar compound and acid
Title: Re: Would this synthetic pathway be possible?
Post by: Babcock_Hall on March 30, 2020, 05:26:53 PM
How do you plan to control the stoichiometry in the first step?
Title: Re: Would this synthetic pathway be possible?
Post by: wildfyr on March 30, 2020, 09:05:48 PM
That's a hell of a way to make acrylic acid hahaha. Avaikabke for about $30 a kg