Oxıdation of alkene with KMnO4 solution or Na2Cr2O7 produce alcohol or ketones or carboxylic acids İ wonder why oxidation of styrene by
Na2Cr2O7 or KMnO4 dont lead to Phenethyl alcohol or phenylacetic acid?
Also oxidation of alkene (carbon with two hydrogen) lead to CO2 and Carboxylic acid or alcohol
Oxidation of styrene with KMnO4 or Na2Cr2O7 lead to Benzoic acid and CO2 or another thing?
Also we know oxidation of ethyl benzene with Na2Cr2O7 lead to Phenylacetic acid but why not for styrene? carbon in alkene group in styren should be
more active than carbon in alkane group in ethyl benzene
[Edited on 19-9-2010 by hector2000]behemoth - 19-9-2010 at 03:40
Oxidation of styrene with KMnO4 or Na2Cr2O7 lead to Benzoic acid and CO2 or another thing?
[Edited on 19-9-2010 by hector2000]
That is correct. KMnO4 will cleave alkenes on the double bond giving ketones or aldehydes, the latter being further oxidized to the corresponding
carboxylic acids by excess KMnO4. There are procedures where styrenes are cleaved by aqueous KMnO4 to corresponding benzaldehydes, yields are not very
high though.spong - 19-9-2010 at 03:58
I think it would give you styrene oxide which could then give you acetophenone or perhaps benzaldehyde because of the double bond.behemoth - 19-9-2010 at 04:12
For styrene --> styrene oxide you will need oxidants containing a peroxo-group like oxone(R), peracids, peroxides or hypochlorite (bleach),
hypobromite.
The styrene oxide can then be opened in acidic aqueous solution to phenylethane(1,2)diol. Rearrangement to phenylacetic aldehyde is also possible.
I wonder if styrene would be cleaved to benzaldehyde according to patent US 808095 (see that thread) nicely, eg. without further oxidation to benzoic acid.
[Edited on 19-9-2010 by behemoth]zed - 19-9-2010 at 17:23
Styrene is readily oxidized, and rearranged into phenylacetic acid via the Willgerodt Reaction. There is even a microwave version of the reaction.
Since this method works, the reaction conditions are easy to produce, and the reagents are cheaply and readily acquired......Other oxidations aren't
usually attempted.
[Edited on 20-9-2010 by zed]behemoth - 20-9-2010 at 07:08
Styrene is readily oxidized, and rearranged into phenylacetic acid via the Willgerodt Reaction. There is even a microwave version of the reaction.
Since this method works, the reaction conditions are easy to produce, and the reagents are cheaply and readily acquired......Other oxidations aren't
usually attempted.
[Edited on 20-9-2010 by zed]
There is a thread regarding the Willgerodt reaction of styrene: http://www.sciencemadness.org/talk/viewthread.php?tid=6513
apparently the reaction conditions are not easy to produce (remember that chinese patent CN1110677) for the Willgerodt reaction itself. And reagents
like morpholine for the Kindler variation are not cheaply and readily acquired.
[Edited on 20-9-2010 by behemoth]zed - 20-9-2010 at 14:32
That's a reasonably good link, and there are others.
Overall, I suppose it depends on what your definition of easy is.
Heating readily available Styrene, Isopropyl Alcohol, Sulfur, and Ammonium Hydroxide.........Under a few atmospheres of pressure, seems easy to me.
Now, making phenylacetic acid, and using it to synthesize illicit materials, may be an immoral pursuit......But, like many harmful, yet profitable
enterprises, it isn't difficult.
[Edited on 20-9-2010 by zed]
[Edited on 20-9-2010 by zed]behemoth - 21-9-2010 at 07:54
...Heating readily available Styrene, Isopropyl Alcohol, Sulfur, and Ammonium Hydroxide.........Under a few atmospheres of pressure, seems easy to
me...
Well, did you actually read the corresponding threat? No one could reproduce that chinese patent and I doubt that you would.zed - 21-9-2010 at 17:05
Perhaps no-one in that particular thread was successful. Experimenters elsewhere have reported success.
At any rate, since for the general overall well being of humanity, it is probably best that this reaction does not work, I retract my former
statements.
The Willgerodt Reaction doesn't work very well, and the reagents are impossible to acquire.
[Edited on 22-9-2010 by zed]hector2000 - 22-9-2010 at 07:42
I wonder hydration of alkyne by Mercury salt and sulphuric acid as atalyst ,should lead to aldehyde or ketone but in phenylacetylene i think we will
have acetophenone not phenylacetaldehyde.why?!
[Edited on 22-9-2010 by hector2000]zed - 22-9-2010 at 15:37
In the case of the Styrene 1,2-diol, the reaction generally proceeds by the elimination of one of the -OH groups followed by rearrangement.
The Benzylic carbon, at position 1, forms (by far) the most stable ionic intermediate.
Therefore, the -OH at position 1, is the easiest to remove by dehydration.
Once the ball starts rolling down hill, a molecule of water is removed, a hydrogen atom shifts, and bingo! You end up with phenylacetaldehyde.
This is basis of the well known oxidation of propenyl benzenes, via peroxide-formic acid, to the epoxide, followed by hydrolysis to the diol, and then
dehydration/rearrangement to the benzyl-methyl-ketone ( phenyl-2-propanone).
[Edited on 22-9-2010 by zed]
[Edited on 22-9-2010 by zed]Refinery - 9-5-2020 at 13:35
Has anyone got any further references on this reaction?
It implies that styrene could be oxidized with iodine, mercury oxide and water? All of the compounds dissolve in water in minute quantities, should it
be enough to actually procceed the reaction?
Quote:
Styrene oxide can be prepared by the action of iodine, water, and mercuric oxide on styrene.1 The procedure described has been published
Hibbert and Burt, J. Am. Chem. Soc. 47, 2240 (1925).
S.C. Wack - 9-5-2020 at 14:49
Ether is involved, your reference has nothing to do with this, and the correct reference is Tiffeneau, Compt. rend. 140, 1595 (1905), who soon made
phenyl-2-propanol from it with MeMgI.Johnny Windchimes - 9-5-2020 at 15:28
Ether is involved, your reference has nothing to do with this, and the correct reference is Tiffeneau, Compt. rend. 140, 1595 (1905), who soon made
phenyl-2-propanol from it with MeMgI.
Hey hey hey, as long as we are randomly oxidizing styrene non-sequiter to the OP's intent....
Styrene + O3 = Benzaldehyde
Serious cautionary note: H2O2 is made in this reaction as a byproduct. H2O2 + Acetone (being their solvent used here), can generate
EXPLOSIVE peroxides - neutralize them before even thinking about distilling, and use testing strips to be safe~!
Better yet, read the paper written by professionals and heed their advice~!
I'm firing up my eBay Chinese Ozone generator as we speak~!
*Edit - credit for turning me onto this procedure goes to a science madness member by the name of Melgar, as he originally mused about in the big
benzaldehyde sticky thread.
