Melange_aqueux
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Solvent free MnO4 oxidation
Hi everybody,
this is my first post so I'll try to be coherent. English isn't my first language please be comprehensive for the strange words... okay
Few days ago I saw an interesting document who is explaining how to perform oxidative pathway with a solvent free rnx using permanganate coupling with
Al2O3 and a hydrated copper salts ( CuSO4 * 5 H2O ).
Because this rnx is a "Green Chemistry" one, and look like easy to perform I would like to go deeper it this field of knowledge.
My primary objective is to acheive a solvent free oxidation of a cyclic ether ( to be precise Tetrahydropyrane ) to the corresponding ester (
gamma-valerolactone ). But I still have some obscur questions and I appreciate if someone can help me with them.
Q1 : I would like to know if anybody here have ever performed that kind of synthesis.
Q2: Obiviously the oxidant is MnO4 and I would like to know what is the use of Al2O3 in this rxn. The mix of these two compounds is not supposed to
make a heavy exothermic process if energy is give to them. I would like to know what are the risk of overoxidation ( are they probable?) and what
about the formation of peroxyde? Is the Copper salts used as catalysis?
Q3 : I try to find "general synthesis protocole" for that kind of synthesis ( Solvent free MnO4 oxidation ) and I found nothing in my organic chem
books. Can I find it somewhere else ( books?, website?). Thank you again all !!!
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not_important
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By MnO4 I assume you mean permanganate MnO4(1-).
These sorts of reactions are fairly new, all but the newest textbooks are likely not to mention them. Your best bet for detailed information is the
article you read, or the journal paper it referred to, any related paper that the article referenced, and possibly more recent papers that referred to
this paper.
Pay close attention to the exact type of alumina used as there is a range of properties depending on how the alumina has been treated.
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PHILOU Zrealone
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Maybe an oxydation with O2 on a solid MnOx, CuSO4.H2O,Al2O3 catalyst...in a liquid or gaseous phase...this would obviously be solvant free; actually
the reactant might be the solvent! All the pertinent infos must be in your document. Without it or clear references, little people here will be able
to help.
Peroxydes and Manganese (permanganates) + Copper are not really what I woul call good friends. Peroxydes should be of no concern.
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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Rosco Bodine
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Copper Bismuth Manganite oxidation catalyst
This one might interest you
US4062772
Attachment: US4062772 Bismuth Copper Manganite Spinel.pdf (203kB)
This file has been downloaded 447 times
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Nicodem
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Melange_aqueux, do you mind being more specific? Are you asking about oxidations with MnO2 or KMnO4 (or other permanganates)? There is no such thing
as MnO4 since the highest chemical oxidation state of Mn is VII (only a manganese peroxide can fit such an empirical formula, but I don't think you
got that in mind).
Also, you can not obtain gamma-valerolactone by the oxidation of tetrahydropyran. Utmost you get delta-valerolactone, quite a different compound.
With your Q3, are you asking about references? If so, then show that you did some effort by yourself by going to the library. Then list the references
you got and we shall fill in the missing ones. Otherwise, you just appear lazy, which is not really nice.
…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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Melange_aqueux
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Thank you guys! I will dig on it and come back soon.
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chemrox
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JOC & JCS
JCS, Journal of the Chemical Society, publishes Green Chemistry articles on a regular basis. JOC, an ACS pub, prints "Notes" on Green Chem regularly.
In the type of situation you're describing, the alumina is a substrate for supporting the reagent and/or catalyst. Often done in microwave ovens...
anyway, as Nicodem suggests, please be more specific with the information you have and do please do some basic research. If you can't get the
articles you find I'm sure help can be found here getting them.
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
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Rosco Bodine
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catalyst carrier from precipitated gels
You may also find this interesting
US1935178
Attachment: US1935178 Metal oxide sols.pdf (295kB)
This file has been downloaded 521 times
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