BauArf56 - 25-7-2021 at 07:01
I recently made some nice chromium oxide peroxide (CrO5) by mixing homemade sodium chromate solution (made from nichrome wire, bisulfate and bleach)
and acidic hydrogen peroxide. I expected nothing that nothing would have happened, but it did work and in a few minute it decomposed back into green
trivalent chromium.
Now i readed that it is a powerful oxidizer in organic chem, but not used due to instability. But i'd like to try either (by stabilizing it with ethyl
acetate), so i want to do some basic experiment with it. For example what would happen if i mix it with acetone? Does it oxidize to some aldehyde? and
what with ethanol? does it give acetic acid?
And outside organic chemistry, would it set on fire alcohols or glycerine?
CrO5 is a very interesting compound, but i wasn't able to find much infos.
extra question: is sodium bisulfate strong enough to make chromium trioxide from a chromate?
[Edited on 25-7-2021 by BauArf56]
[Edited on 25-7-2021 by BauArf56]
Bedlasky - 25-7-2021 at 11:20
CrO5 isn't stable. You can prepare adduct with pyridine:
https://woelen.homescience.net/science/chem/exps/cr_peroxo_p...
This is only way how to stabilize and isolate CrO5 I know. I don't think that anyone use CrO5 in organic chemistry. It is too much unstable.
If you want selectively oxidize primary alcohols to aldehydes, look for pyridinium dichromate or pyridinium chlorochromate. Another ways are dimethyl
sulfoxide based methods or Dess–Martin periodinane/2-iodoxybenozic acid.
And answer for your extra question: Sodium bisulfite reduce chromate to soluble Cr(III) sulfate complex. Sodium bisulfite make solution acidic, so
reduction is possible. But sodium sulfite cannot reduce chromate. You need acidic environment for this.
[Edited on 25-7-2021 by Bedlasky]
JJay - 3-8-2021 at 15:58
It's been far too long since I was on here....
Pyridine can be used to stabilize chromium VI oxide peroxide, but I believe that bipyridine works better. This paper discusses several uses for
chromium VI oxide peroxide and gives procedures for synthesizing some complexes: https://www.sciencedirect.com/science/article/abs/pii/S00404...
This article details a synthesis of bipyridine: http://orgsyn.org/demo.aspx?prep=cv5p0102
arkoma - 4-8-2021 at 02:36
^^^yes it has been too long. Welcome home.