05-18-01 00:10
No 195216
In a old hive post...
("Nitroaldol Reaction in Aqueous Media: An Important Improvement of the Henry Reaction"
Experimental information (general):
To a mixture of nitroalkane (nitromethane, ethane, propane, etc.) (50mmol)
and aldehyde (50mmol), in NaOH .025M (150ml), was added CTACl (cetyltrimethylammonium chloride) (5mmol) at room temperature. The mixture was stirred at room temperature for the appropriate time (2h for benzaldehyde)and then saturated with aqueous NaCl and extracted with Et2O (4 tms 30ml). The organic phase was dried (MgSO4) and concentrated, and the crude nitroalcohol was purified if necessary.
That is one mother-fucking short reaction time, don't you think? But again, with
regard to the nitroalcohol to nitroalkene transformation, I'm stumped. )
Could CTAC, Cetyltrimethylammoniumchloride aka Cetrimide or
Cetrimonium Chloride be used instead of
- Ethylenediammonium diacetate
- n-butylamine
- cyclohexylamine
in a reaction between benzaldehyde & nitroethane ?
any pointers appreciated !!!
(Hive Addict)
05-18-01 02:36
No 195240
Did they list the actual reference?????????????????
Puleeeesssseeee
Do Your Part To Win The War
(Stranger)
05-18-01 03:02
No 195246
Hive post: No 108593
JOC, 1997, 62, 425-427
the same hive post had this follow up,
----------------------------------------
(Rhodium
Administrator posted 12-17-98 02:47 AM
This rxn would be very useful when one wants to make cathinone and ephedrine analogs though.
The acetyl esters of phenylnitropropanols are converted to phenylnitropropenes when treated with alcoholic KOH (see the refs in my pseudonitrosite FAQ for details), but I don't know about the nitroalcohols themselves. Try it out in the lab yourself, it won't take much of your time. )
----------------------------------------
Has anyone tryed this? if it works then great cause its very OTC in hair and beauty products!
(Hive Addict)
05-18-01 12:26
No 195340
Here is a little of the info from that article
Nitroaldol Reaction in Aqueous Media: An Important Improvement of the Henry Reaction
J. Org. Chem., 62 (2), 425-427
benzaldehyde + nitromethane --> 1-Phenyl-2-nitroethan-1-ol
70% yield in 2 hours
benzaldehyde + nitropropane --> 1-Phenyl-2-nitrobutan-1-ol
71% yield in 2 hours
p-nitrobenzaldehyde + nitroethane --> 1-(p-Nitrophenyl)-2-nitropropan-1-ol
72% yield in 4 hours
General Procedure for the Nitroaldol (Henry) Reaction.
To a mixture of nitroalkane (50 mmol) and aldehyde (50 mmol), in NaOH 0.025 M (150 mL), was added CTACl (cetyltrimethylammonium chloride) (5 mmol) at room temperature. The mixture was stirred at room temperature for the appropriate time and then saturated with NaCl and extracted with Et2O (4 × 30 mL). The organic phase was dried (MgSO4) and concentrated, and the crude nitro alcohol, if necessary, was purified by flash chromatography (EtOAc/cyclohexane, 2:8).
Do Your Part To Win The War
(Stranger)
05-19-01 09:29
No 195595
Could one of the chem gods inlighten a newbee !!
If i understand (or not) correctly, then using CTACl
produces the 1-Phenyl-2-nitrobutan-1-ol which then needs
the further process of alcoholic KOH to form the phenylnitropropene which can then be reduced to honey.
Why does Ethylenediammonium diacetate, n-butylamine and
cyclohexylamine form the nitropropene, but the catylist
Cetyltrimethylammoniumchloride forms the phenylnitropropanol?
They all have the amine group, is the chloride the prob?
As is evident swim is not chem literate, so education is
appeciated. foxy2?
cheers ears
(Hive Addict)
05-19-01 10:13
No 195600
I don't know what the mechanisms are, all I can give you is what the reference states. If you want a prop-2-amine from an aldehyde then the other procedure followed by reduction of the nitropropene would probably bee easier imo.
What is this??
"the further process of alcoholic KOH to form the phenylnitropropene which can then be reduced to honey."
Do you have a reference for the KOH conversion??
I think this reaction would be most useful for the production of PPA(phenylpropanol amine) which can then bee used in various synthesis. I think that Al/Hg would reduce the nitro to an amine giving you PPA.
Do Your Part To Win The War
(Stranger)
05-20-01 02:54
No 195716
Hi Foxy2,
I proberly need to explain myself a little brighter, I have no knowledge (nor could i find in search engine) on how to make n-butylamine or cyclohexylamine and to make Ethylenediammonium diacetate you need to find
Ethylenediammonium at a photo shop and make the acetate
from it, Swim has found Ethylenediammonium as a dry powder but mixed with a siquest-a-carbonate thingy, well it all looks like quite a bit of work to get a cataylist for this reaction:
(To 55 g (0.5mol) Benzaldehyde in a 500ml Flask were added 40 g (0.5mol)Nitroethane and 10ml Cyclohexylamine. All was refluxed for 6h on a waterbath. The result were 2 layers. One orange layer at the bottom with phenyl-2-nitropropene and a clear layer at the top with cyclohexylamine and
maybe a little bit (~1ml) of H20. 50ml of H2O were added and then sucked off with a pipette until the phenyl-2-nitro-propene crystallized (it crystallized when it came in touch with air in presence of 15ml H2O).
I added 200ml 95% denaturated ethanol to the orange crystals. The color of the now needle-like crystals changed from orange to white-yellow.
The crystals were filtered. Yield 65 g, 78% of theory.)
Could you suggest any other cataylist for this reaction????
or how would one set about to make n-butylamine or
cyclohexylamine??? r there OTC sources??
As mentioned swim has searched before asking, maybe the answer is right under my nostril or is not that close at all.
Your guidence and patience appreciated Foxy2!
(Hive Addict)
05-20-01 10:20
No 195741
"Swim has found Ethylenediammonium as a dry powder but mixed with a siquest-a-carbonate thingy"
IOC, would you kindly PM me with the name of whatever you were talking about in that quote.
I don't quite understand what a siquest a carbonate thingy is, sorry?
Do Your Part To Win The War
(Stranger)
05-21-01 03:16
No 195850
OK Foxy, I got off my fat arse and went to the libary and did some more searching i found that:
The dry powder thingy was infact
ethylenediaminetetraacetic sodium salt (cas 64-02-8)
& sodium sesquicarbonate (cas 533-96-0)
basically not what one is lookin for huh!
cause EDTA is not EDA, which from lookin around EDA is what
everyone wants for the birch reaction.
But I did find this on re-reading old posts......
04-21-00 No 108534
Preparation of 3,4-methylenedioxyphenyl-2-nitropropene (from piperonal)
In Pihkal, Alexander Shulgin mentions that the preparation of
MDP-nitropropene can be carried out in cold methanol with aqueous sodium
hydroxide as the base. In fact, this method is even more reliable, and
gives higher yields than the other method advocated by the dear doctor in
his book.
15g of piperonal was dissolved in 40ml of methanol under stirring in a
250ml Erlenmeyer flask. When all of the piperonal had dissolved, 7.1g
nitroethane was added to the solution. The flask was put in a ice/salt-bath
with magnetic stirring, and when the temperature of the solution had
dropped to 0°C, an ice-cold solution of 4g of NaOH in 20ml dH2O was added
at such a rate that temperature never rose above 10°C. A white precipitate
formed at the bottom of the flask during this addition, which was broken up
with a glass rod. The stirring was continued for another hour, while the
temperature of the solution was never allowed to rise above 5°C, and at the
end of this time, 100 ml of ice-cold dH2O was added to the solution, which
caused even more precipitation of white solid. The whole slurry was poured
into 100 ml of ice-cold 2M HCl solution in a 500ml Erlenmeyer flask, which
was gently swirled, and there was a slight bubbling and fizzing, with the
color of the solution shifting from white to blue to green to yellow in
under a minute. Quite spectacular! When the fizzing had subsided, the
solution was once again placed in in an ice-bath with magnetic stirring.
When the temperature had dropped to about 5°C, the solution was clear with
yellow granules of crude product at the bottom. The granules were filtered
with suction, and recrystallized from IPA. After air-drying, the
canary-yellow crystals amounted to a yield of 65-70% of theory.
So if I read the post correctly Naoh is used as base instead of any of the amines?????
I do not have TS2 but every other bee that does already new this I guess.
Back to the drawing board for making nitroethane without all that DCM.........still waiting for your follow up post Obit!!
cheers Foxy2
(Chief Bee)
05-22-01 17:46
No 196126
Yes, In this case, the NaOH acts as a base instead of any amine.
The reason the nitroalcohol is formed in the PTC reaction above is perhaps due to the large excess of water in the rxn mixture, preventing the dehydration to the nitroalkene.
http://rhodium.lycaeum.org