MrMario
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Someone experience with Cycloalkenes to cyclocarbonyls
I read that cyclohexene/cyclopentene can be converted with N2O to produce cyclohexanon and cyclopentanon and would like to know more about this
procedure. If anyone has experience, please let me know.
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CharlieA
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Where is your reference, please?
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MrMario
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http://link.springer.com/article/10.1023%2FA%3A1016564818065...
U need to click on "Look inside" to see the preview of the paper.
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UC235
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The reaction conditions for this are 250C, 100atm in an autoclave.
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CharlieA
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Thanks for the link. I don't think that the 250*C is a problem, but 100 atm? How do you propose to develop (and contain) that much pressure? You are a
much braver man than I, Mario. If you try this, please let us know how it turns out-Ciao, Charlie
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DraconicAcid
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100 atm of N2O? That's a laugh and a half.
I'm sure it would be much easier to add water across the double bond with dilute sulphuric acid, and then oxidize the alcohol with bleach.
[Edited on 22-2-2016 by DraconicAcid]
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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clearly_not_atara
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If you just feel like running a vapor-phase reaction, singlet oxygen (which is dangerous) gives 3-hydroperoxycyclopentene. This can be converted into
cyclopentenone in a variety of ways, or directly to more interesting compounds.
Otherwise I believe the traditional answer involves mercury acetate and potassium dichromate.
[Edited on 23-2-2016 by clearly_not_atara]
[Edited on 23-2-2016 by clearly_not_atara]
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UC235
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Quote: Originally posted by clearly_not_atara ![](images/xpblue/lastpost.gif) | If you just feel like running a vapor-phase reaction, singlet oxygen (which is dangerous) gives 3-hydroperoxycyclopentene. This can be converted into
cyclopentenone in a variety of ways, or directly to more interesting compounds. |
Actually, this can be done in the liquid phase (perhaps diluted in methanol) in oxygen atmosphere using methylene blue or rose bengal as a sensitizer
and a fairly powerful light source. Reduction to the allylic alcohol is trivial involving aq. Na2SO3 or zinc and acetic acid
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DJF90
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Quote: Originally posted by UC235 ![](images/xpblue/lastpost.gif) |
Actually, this can be done in the liquid phase (perhaps diluted in methanol) in oxygen atmosphere using methylene blue or rose bengal as a sensitizer
and a fairly powerful light source.
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See here for further elaboration: http://curlyarrow.blogspot.co.uk/2007/04/fun-with-singlet-ox...
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MrMario
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Sooo, i guess it's not something what could be done as a hobby chemist.. Don't think I have the equipment to reach ~100 bar.
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Dr.Bob
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Reaching 100 bar is not a problem at all. Containing it in one place is, however. I bet Bert can elaborate on the first step.
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CuReUS
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Its a russian paper,what do you expect ? ![:D](./images/smilies/biggrin.gif)
Mario,if you want to do something exotic to get the ketone from the alkene,You could try the Wacker oxidation ,which gives very high yields (97 % for
cyclohexene)
http://www.sciencemadness.org/talk/viewthread.php?tid=10007#...
but It will to cost you ![;)](./images/smilies/wink.gif)
[Edited on 24-2-2016 by CuReUS]
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