Pages:
1
2 |
Sandmeyer
National Hazard
Posts: 784
Registered: 9-1-2005
Location: Internet
Member Is Offline
Mood: abbastanza bene
|
|
There is a way to reduce the C=C bond conjugated to an electron-withdrawing group, (like in nitrostyrenes) using p-dihydroxypyridines which be made
from readily available aliphatic precursors.
Diethyl 2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate
A mixture of ethyl acetoacetate (20 mmol), hexamethylenetetramine (8 mmol) and ammonium acetate (10mmol) is irradiated for 100s (45W, Synthewave
S402). After cooling, the solid is filtered, washed with ethanol and dried under vacuum; m.p. 188-190°C
Typical procedure for the reduction of olefins by DHP
Silica gel (4g), nitrostyrene (0.6g, 4 mmol) and DHP 1a (1.5g, 6 mmol) are diluted in methylene chloride (20 mL). The solvent is quickly evaporated
in vacuo. The resulting solid is irradiated for 4 min (150W, Synthewave S402) under a nitrogen atmosphere, cooled and filtered. The filtrate is
stirred for 20 min with 6N HCl (20 mL). The organic layer is dried on MgSO4 and concentrated in vacuum to afford 2-phenylnitroethane (yield 78%)
http://www.mdpi.org/molecules/papers/70700528.pdf
|
|
Rosco Bodine
Banned
Posts: 6370
Registered: 29-9-2004
Member Is Offline
Mood: analytical
|
|
iron filings and hydrochloric acid
If you have some means of good stirring ,
such as a rapid reversing agitator which works something like a washing machine agitator , but goes about four full revolutions each direction , you
can run
a very efficient conversion of phenylnitropropylene to phenylacetone at about 95% yield of .999 fine product in
one step .
The PNP is added to dilute aqueous ferric chloride and iron filings and the mixture is heated and stirred until the PNP melts and begins to emulsify ,
then concentrated HCl is gradually added ,
at such a rate as the heat of reaction
allows . A water trap with a sample takeoff or return to reaction 3 way stopcock is interposed between the reaction flask and a tall reflux
condenser
placed above the water trap . Until the addition of the HCl is complete and the reduction finishes , all of the reflux is returned to the reaction .
As the reduction of the PNP proceeds , first the oxime is formed as an intermediate , but in the acidic reaction
mixture the oxime is further converted to the ketone , which will steam distill from
the mixture and accumulate in the water
trap with phase separation , from the water . In order to make the phase separation occur cleanly instead of having
a milky emulsion of phenylacetone and water accumulating in the trap , some addition of benzene to the reaction flask
will give a twofold benefit , in that the separation of the desired product with benzene occurs cleanly , and due to the lowered density becomes the
upper layer
in the water trap , so that the valve can be adjusted to return the separated lower
layer of water at about the same rate as it
accumulates , so that the water layer in the trap remains low as the phenylacetone layer steadily increases and is drawn off periodically . The
pure
phenylacetone is easily separated from its
solution in benzene simply by heating gently to drive off the far more volatile benzene . IIRC , a small amount of hydroquinone should be added to
the
phenylacetone as an anti-oxidant preservative and polymerization inhibitor ,
prior to any isolation , vacuum distillation ,
or storage of the material , as it is subject to the same instabilities as is typical of other similar ketonic-aldehydic substances like for example
benzaldeyde .
[Edited on 15-6-2005 by Rosco Bodine]
|
|
Rosco Bodine
Banned
Posts: 6370
Registered: 29-9-2004
Member Is Offline
Mood: analytical
|
|
alcoholic hydrazine and 5% palladium on charcoal
Hydrazine reduction of phenylnitropropene...
imagine that...what a curious coincidence
This appears interesting and I don't recall seeing this having been mentioned. US2768209 describes P2NP reduction using hydrazine in alcohol ....See
the patent title elaborated briefly in the next to last paragraph of Example 8 .....
Of course what I probably meant to say is regardless of the patent title there is likely nothing of interest here except this shows a good possible
analogous method for reduction of m-dintrobenzene to m-nitroaniline See Example 5. Pay no attention to the patent title, move along, these are not
the droids you are looking for
Attachment: US2768209 Hydrazine reduction of phenylnitropropene.pdf (180kB) This file has been downloaded 1916 times
|
|
Tsjerk
International Hazard
Posts: 3032
Registered: 20-4-2005
Location: Netherlands
Member Is Offline
Mood: Mood
|
|
In the last paragraph of example 8 the author is talking about reduction to yield 2-amino 1-phenyl propene-1 and claiming that this is amphetamine.
But the amphetamine is the propane.
Would this reduction yield the fully reduced product or the propene?
|
|
ScienceSquirrel
International Hazard
Posts: 1863
Registered: 18-6-2008
Location: Brittany
Member Is Offline
Mood: Dogs are pets but cats are little furry humans with four feet and self determination!
|
|
Quote: Originally posted by Tsjerk | In the last paragraph of example 8 the author is talking about reduction to yield 2-amino 1-phenyl propene-1 and claiming that this is amphetamine.
But the amphetamine is the propane.
Would this reduction yield the fully reduced product or the propene? |
It is a typo, the product is the propane.
|
|
Rosco Bodine
Banned
Posts: 6370
Registered: 29-9-2004
Member Is Offline
Mood: analytical
|
|
It appears likely that the reduction is likely complete and the propylene is converted to propane ......however there is a journal article by the
inventor which is likely to have additional detail. File attached below, thanks to solo.
Hmmm....not one mention of amphetamine appears in the journal article, and yet six months later a patent application is made taking five years more to
issue, a patent making one and only one claimed compound added to the list of those published in the journal article......very interesting huh.
Catalytic Reduction with Hydrazine
Lester P. Kuhn
J. Am. Chem. Soc.
1951, 73 (4), pp 1510–1512
DOI: 10.1021/ja01148a029
Attachment: Catalytic Reduction with Hydrazine.pdf (387kB) This file has been downloaded 1608 times
There are similar methods using hydrazine and either powdered zinc or powdered magnesium which are mentioned. It would seem that the hydrazinium
monoformate reagent could be formed in alcohol by alternate schemes using hydrazine sulfate as a starting material with added steps. So it appears
there are 3 schemes by which hydrazine may be useful for the reduction of phenylnitropropylene to the "methylphenylethylamine" or
"phenylisopropylamine" or amphetamine.
http://www.erowid.org/archive/rhodium/chemistry/nitro2amine....
http://www.erowid.org/archive/rhodium/chemistry/nitro2amine....
Maybe we should ask "Dr. Know, M.D." since he is a medical doctor and knows about this complicated Jedi mind trick kind of stuff
http://2.bp.blogspot.com/-Uu7-3KizJE8/T34iAcUc7SI/AAAAAAAAID...
[Edited on 15-5-2012 by Rosco Bodine]
[<a href="u2u.php?action=send&username=bfesser">bfesser</a>: this is not a politics thread; replaced
image with link]
[Edited on 7/7/13 by bfesser]
|
|
Rosco Bodine
Banned
Posts: 6370
Registered: 29-9-2004
Member Is Offline
Mood: analytical
|
|
Hydrazine Sulfate reduction of Nitrourea to Semicarbazide
Here is another obscure reaction showing the reduction of a nitro compound by Hydrazine.
GB790066 Semicarbazones via Hydrazine and Nitrourea
I did a search to see if GB790066 had ever been brought up by anyone before as a matter of interest
http://www.sciencemadness.org/talk/viewthread.php?tid=544#pi...
http://www.sciencemadness.org/talk/viewthread.php?tid=544&am...
But the patent GB790066 says that the (apparent) "reduction" of produces N2O as a byproduct and nitrous oxide would not be expected from an ordinary
reduction where H2O would seem to be the anticipated byproduct. Strange and interesting. A similar unexpected modified "reduction" may also occur
when hydrazine is used for "reduction" of other nitro compounds.
The reduction of nitrourea by hydrazine to semicarbazide is not a conventional reduction, but involves formation of an unstable intermediate hydrazine
salt of nitrourea, which decomposes with evolution of nitrous oxide ....similarly perhaps as does ammonium nitrate decompose under certain conditions
to evolve nitrous oxide. So after 10 years the subject of GB790066 is being revisited. This thread seemed as good a place as any from which to
reflect.
Attachment: GB790066 Semicarbazide from Nitrourea and Hydrazine Sulfate.pdf (361kB) This file has been downloaded 746 times
[Edited on 29-3-2013 by Rosco Bodine]
|
|
chemrox
International Hazard
Posts: 2961
Registered: 18-1-2007
Location: UTM
Member Is Offline
Mood: LaGrangian
|
|
Quote: Originally posted by enima |
I'm personally don't like metal + hcl reductions they are very unreliable and yields are piss poor. |
The workup from MD-nitrostyrene after using HCl and Fe was messy and involved a lot of liquid. I think it's time to brave the LAH "barrels." Or the
HgCl2/Al foil.
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
|
|
chemrox
International Hazard
Posts: 2961
Registered: 18-1-2007
Location: UTM
Member Is Offline
Mood: LaGrangian
|
|
Quote: Originally posted by Rosco Bodine |
Maybe we should ask "Dr. Know, M.D." since he is a medical doctor and knows about this complicated Jedi mind trick kind of stuff
[Edited on 15-5-2012 by Rosco Bodine] |
Let's just ask him for money. That he does know.
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
|
|
Rosco Bodine
Banned
Posts: 6370
Registered: 29-9-2004
Member Is Offline
Mood: analytical
|
|
Gresham's Law Enforcement .....
it's a tough job but somebody has got to do it.
A penny saved a long time ago is worth more than the penny made now.
Who ya gonna call when Gresham's Law has done its deed on the zinc?
Aluminum?
Wooden nickels are the coin of the future. Hey that's real "progress" huh.
|
|
S.C. Wack
bibliomaster
Posts: 2419
Registered: 7-5-2004
Location: Cornworld, Central USA
Member Is Offline
Mood: Enhanced
|
|
Preferred coinage: Canadian Pd Maple Leafs and the various sizes of US Mint Pt.
Note US3458576 for uses of Pd without hydrazine.
Hydrazine hydrate is interesting with Ni reductions as well.
|
|
Mildronate
Hazard to Others
Posts: 428
Registered: 12-9-2009
Member Is Offline
Mood: Ruido sintetico
|
|
Its very easy to reduce it with aluminium amalgam or with urushibara nickel. If you whant ketone then you can reduce it with fe/hcl.
[Edited on 30-3-2013 by Mildronate]
|
|
Rosco Bodine
Banned
Posts: 6370
Registered: 29-9-2004
Member Is Offline
Mood: analytical
|
|
Quote: Originally posted by S.C. Wack | Preferred coinage: Canadian Pd Maple Leafs and the various sizes of US Mint Pt.
Note US3458576 for uses of Pd without hydrazine.
Hydrazine hydrate is interesting with Ni reductions as well. |
Yeah it seems we have a "reductive hydrazination" or reductive amination aspect about some of these complex reductions through an
intermediate....distinctly different from a straightforward reduction by hydrogen for comparison.
LOL Another like me, a believer in the "divine right" to keep and bear gold,
silver, platinum, and any arms which may be needed to assure its continued possession in spite of "tax collectors" evil ambitions to divert it to
their own enrichment under false pretense such theft serves what the thief would estimate is the genuinely "greater good" by that thief simply taking
and spending what is rightfully anothers. Beware of the thief in the night and even moreso beware of the thief who so boldly, brazenly comes by day.
Revenuers are just no damn good, and they have been around since liars and thieves were invented
|
|
palico
Hazard to Self
Posts: 63
Registered: 1-10-2013
Member Is Offline
Mood: No Mood
|
|
I had a dream also. I reduced phenyl-2-nitropropene simply with metallic sodium in ethanol.
Can this dream become reality ?
Anyone has ever tried this workup ?
What's wrong with this simple method ?
|
|
Pages:
1
2 |