Chemical Forums
Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: ss1234 on October 24, 2016, 01:56:07 PM
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Does anyone know all of the steps to the synthesis please?
This is what I have so far is it on the right step?
1. Br2/FeBr3
2. methyl 1-cyclohexene carboxylate
3. Pd (Oac)2
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It is a forum rule that you must show your attempt or thoughts before we can help you. Have you learned any reactions that look similar?
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Heck reaction with cyclohexene gives mixture of products with low yield. Probably the same concerns cyclohexene derivatives.
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I would have thought that the electron-withdrawing group causes a preference in the regiochemistry.
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I think it might help if you draw the whole structure of the ester instead of just COOMe and then look at the positions of double bond and the ester.
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The Heck-reaction does not remove the doublebond?
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The Heck-reaction does not remove the doublebond?
Reduction of double bond in the reaction product will not be a problem but add one step more.
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Yes, the doublebond will be tetrasubstituted so it will need som pressure. I can not see the step i the list though?
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Well, it looks like organometallic chemistry is being discussed in class. I agree with the basic methodology. Might another organometallic reagent work?
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A cuprate would do the trick offcourse, that would give the saturated, desired product.
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Does anyone know all of the steps to the synthesis please?
This is what I have so far is it on the right step?
1. Br2/FeBr3
2. methyl 1-cyclohexene carboxylate
3. Pd (Oac)2, Et3N
4. H2/pd
Please confirm
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Ok, I did not se the last step in the first list, the H2/PdC step.
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Ok, I did not se the last step in the first list, the H2/PdC step.
Does it seem complete, do you think there are any mistakes? Thank you so much for your help
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As I told previously, with unsubstituted cyclohexene, many compounds are formed, vinylation and unconjugated products prevail. These main products do not contain your needed carbon skeleton.
I think that much better will be
1. Anti-Markovnikov HBr addition to cyclohexene
followed by
2. Friedel-Crafts alkylation of benzene.
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But there is a estergroup present, does not that give a better result with Heck?
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Ok, I did not see the last step in the first list, the H2/PdC step.
Does it seem complete, do you think there are any mistakes? Thank you so much for your help
That would seem to do it.
Re: Ester and Heck
I'm presuming a Heck must have been part of the poster's arsenal of reactions. It certainly looks like a question in a chapter on organometallic chemistry. I thought it might have used a cuprate and asked whether that might have been an option.
It is always a challenge for posters to try to give an answer to a question in a book or class in which we have not read nor attended. I know when I taught, I used the problems to practice mechanisms that were taught (and on exams to test as many concepts or mechanisms as practical so students would be rewarded for learning them). I'm presuming this post is following that principle.
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But there is a estergroup present, does not that give a better result with Heck?
Right, you catched me.
Heck is too nonselective for cyclohezanes. May be Heck-Matsuda?
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Ok, I did not see the last step in the first list, the H2/PdC step.
Does it seem complete, do you think there are any mistakes? Thank you so much for your help
That would seem to do it.
Re: Ester and Heck
I'm presuming a Heck must have been part of the poster's arsenal of reactions. It certainly looks like a question in a chapter on organometallic chemistry. I thought it might have used a cuprate and asked whether that might have been an option.
It is always a challenge for posters to try to give an answer to a question in a book or class in which we have not read nor attended. I know when I taught, I used the problems to practice mechanisms that were taught (and on exams to test as many concepts or mechanisms as practical so students would be rewarded for learning them). I'm presuming this post is following that principle.
There should be nothing wrong with asking for help. I am not a genius. Thank you for your response on this forum.
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I would have thought that the electron-withdrawing group causes a preference in the regiochemistry.
I am under the impression that the ester will help to direct the correct regiochemistry in the Heck. However, other commenters have made me wonder whether or not the sterics are favorable.