Claus
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A question about a reaction involving translocation of carbonyl group of a ketone
The reaction is shown in the attached figure.
I got confused at the very first step...
(What is the function of C5H11ONO2?)
I guess the first step removes a hydogen at the alpha position and the second step is a reduction of a carbonyl group into a hydroxyl group.
Maybe the third step is related to a reaction of an epoxide.
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kmno4
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... and the rest is rather clear
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Claus
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Thank you for answering!
May I ask what happens next?
In the first step a β-nitro ketone forms
In the second step a β-nitro alcohol forms.(?)
In the third step a β-amino alcohol forms.(?)
Or could the third step be a Clemmensen reduction?
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forgottenpassword
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I don't agree that the first step will give a nitroalkane. There are examples of the following:
http://www.orgsyn.org/demo.aspx?prep=v90p0025
http://www.orgsyn.org/demo.aspx?prep=CV6P0840
The other steps, however, I am unsure of.
[Edited on 5-3-2014 by forgottenpassword]
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Nicodem
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Claus, this is no "translocation of carbonyl group of a ketone". The carbonyl group does not translocate. The first one is reduced and the final one
is created. There is no rearrangement involved. Next time please do not ask such questions without citing the reference. Please read the forum
guidelines for further information.
Those are alpha-nitrosation of ketones, not alpha-nitration like in the discussed example.
The alpha-nitroketones can be reduced to the corresponding nitroolefins (see DOI: 10.1016/S0040-4039(00)86767-2) which can then be reduced further to
the corresponding ketones:
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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forgottenpassword
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With the reagents specified I can only find examples of alpha nitroso compounds being produced. What reaction conditions are needed for alpha
nitration of ketones with the same reagents?
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Nicodem
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Quote: Originally posted by forgottenpassword  | | With the reagents specified I can only find examples of alpha nitroso compounds being produced. What reaction conditions are needed for alpha
nitration of ketones with the same reagents? |
For the nitrosations you need alkyl nitrites (usually in acidic media), while alkyl nitrates, like in this case, give nitroketones.
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forgottenpassword
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Oh yes, my mistake. I misread it as amyl nitrite.
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kmno4
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| Quote: Originally posted by Nicodem | | .... this is no "translocation of carbonyl group of a ketone". The carbonyl group does not translocate. The first one is reduced and the final one is
created. There is no rearrangement involved. (...) |
Yes, and no. Carbonyl groups do not jump from one place to another, but 'dissapearing' of one carbolyl group is very strictly connected with cration
of another one.
There is an article titeled "Transposition of Ketones via 2-Nitro Ketones" (DOI: 10.1021/jo01269a007)
It gives full synthetic path from cholestan-3-one to cholestan-2-one exactly (almost) for conditions given in the post by Claus.
Maybe word "transposition" is more suitable than "translocation", but personally I see no difference (these words also function in my native language)
Слава Україні !
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Nicodem
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| Quote: Originally posted by kmno4 | There is an article titeled "Transposition of Ketones via 2-Nitro Ketones" (DOI: 10.1021/jo01269a007)
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It is an interesting synthetic strategy. I was not aware it was that well studied.
| Quote: | | Maybe word "transposition" is more suitable than "translocation", but personally I see no difference (these words also function in my native language)
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I guess you are right about it. Both appear acceptable names for synthetic strategies, but not for reactions (it would imply some sort of a
rearrangement).
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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