DJF90
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Schmidt rearrangement/reaction
One of my many vacational tasks this christmas is to learn about rearrangement reactions. One of the reactions I can find very little information for
is the Schmidt rearrangement. All I have found is that this is a reaction between a ketone and hydrazoic acid, presumably generated in situ, although
this is not of importance.
One thing I cannot find (and definately need) is a mechanism for this reaction. Can anybody help me out here? Thanks in advance.
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stateofhack
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http://www.organic-chemistry.org/namedreactions/schmidt-reac...
http://www.cem.msu.edu/~reusch/VirtualText/rearrang.htm (scroll down)
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DJF90
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I obviously didn't look as hard as I thought. Thanks very much.
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DJF90
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Right I'm now having another problem with this rearrangements work. Rather than start a new thread I'll post the question here. I'm supposed to
predict the major product of several reactions but the last one I can't do.
Ph-CH2COCHN2 --Ag2O/MeOH--> ?
After drawing out the structure for the organic molecule, I appear to have some kind of diazo compound. I'm sure the diazo group would love to leave
as nitrogen at some point in the reaction. The substrate looks as if it could participate in a Favorskii rearrangement, but instead of the leaving
group being a halide, its nitrogen instead. However as there is a C=N bond rather than a C-X bond, I am finding it hard to break the double bond in a
mechanism.
Also, can somebody enlighten me as to the purpose of the Ag2O? It wouldnt form methoxide ions with the methanol would it? Ag2O + 2MeOH => 2Ag+ +
2MeO- + H2O? I am not sure of its purpose here.
I am grateful to anyone who attempts to answer these rather puzzling questions, and I also hope my tutor doesnt browse this board 
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gsd
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THE SCHMIDT REACTION
by HANS WOLFF
Organic Reactions Vol 3
Chapter 8, pp 307-336
This volume scanned by S. C. Wack is available in forum library.
One of the major plus points of OR chapters is their emphasis on reaction mechanisms and of course very extensive literature servay accompanied by
summary in tabular form.
Hope you will get your starting point there.
Gluck and Very Happy Prosperous and Joyous New Year to All 
gsd
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DJF90
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Thanks for bringing my attention to this collection of books. The reaction I posted above is not a Schmidt reaction (AFAIK) and I am still struggling
with it. Am I right in thinking that the starting material is a diazo compound (like diazomethane)? I've tried writing a mechanism for it for over an
hour now and I just cant see anything that would work. I spose it doesnt help that I dont know what the reagent pair do.
EDIT: I have found that the reaction is an Arnst-Eistert, forming a carbene, followed by Wolff rearrangement, yielding a ketene. This will react with
the MeOH to form the methyl ester. However the function of the Ag2O has eluded me. Can anyone shed some light on this?
[Edited on 2-1-2009 by DJF90]
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